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BOSTON PUBLIC LIBRARY 



3 9999 06317 631 5 

57 




UNITED STATES DEPARTMENT OF THE INTERIOR 

FISH AND WILDLIFE SERVICE 



ATTWATER'S PRAIRIE CHICKEN 
ITS LIFE HISTORY AND 

MANAGEMENT ^^..^^ 



NORTH AMERICAN FAUNA 57 




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1 2000 I 



UNITED STATES DEPARTMENT OF THE INTERIOR 

'Harold L. Ickes, Secretary 

FISH AND WILDLIFE SERVICE 
Ira N. Gabrielson, Director 



North American Fauna 57 



ATTWATER'S PRAIRIE CHICKEN 

ITS LIFE HISTORY AND 

MANAGEMENT 



BY 

VALGENE W. LEHMANN 




UNITED STATES 

GOVERNMENT PRINTING OFFICE 

WASHINGTON : 1941 



For sale by the Superintendent of Documents, Washington, D. C. - - - - Price 40 cents 



ABSTRACT 

ATTWATER'S PRAIRIE CHICKEN, a characteristic bird of the Texas 
coastal prairie, is closely related to the now extinct heath-hen of 
northeastern North America. Once abundant in an area extending from the 
coastal tall-grass prairies of southwestern Louisiana and Texas west and south 
to near Port Isabel, it has decreased in numbers as man has exploited its 
habitat, until now it is threatened with the same fate as that of the heath-hen. 

Important factors limiting the numbers of the bird include excessive or 
persistent rainfall during the nesting season, heavy grazing, excessive pasture 
burning, agricultural operations, and overshooting. Management will 
usually involve protection from excessive killing, improvement of food and 
cover, and control of predators and of the kill by hunters. Responsibility 
for this rests with the landowner. 

Optimum prairie chicken range apparently consists of well-drained grass- 
land, with some weeds or shrixbs, the cover varying in density from light to 
heavy; and with surface water available in summer; diversification within 
the grassland type is essential. In the absence of ample refuges for the 
species, probably all other favorable factors together will fail to save 
Attwater's prairie chicken from extinction. 

This number continues the series of the North American Fauna issued by 
the Bureau of Biological Survey, of the United States Department of Agri- 
culture, prior to its transfer and consolidation with the Bureau of Fisheries 
on June 30, 1940, to form the Fish and Wildlife Service, in the Department 
of the Interior. 



CONTENTS 

Page 

Introduction 1 

Former distribution of prairie chickens in Texas 2 

Differences between Attwater's and the other prairie chickens 4 

Attwater's prairie chicken 4 

Lesser prairie chicken 5 

Former abundance of Attwater's prairie chickens 6 

Present distribution and numbers 7 

Habits 10 

Courtship and mating 10 

Nesting 14 

Growth and development of young 16 

Brood size 18 

Juvenile mortality 19 

Family disintegration 19 

Annual increase 20 

Flocking 20 

Seasonal movements 21 

Spring 21 

Summer 22 

Fall and winter 24 

Food 25 

Habitat requirements 30 

Kind of environment best suited 30 

Character and density of vegetation 30 

Topography 30 

Water 31 

Seasons of scarcity 31 

Limiting factors 31 

Natural factors 32 

Rainfall during the nesting season 32 

Floods 35 

Drought 35 

Hurricanes 35 

Hail 35 

Local storms 36 

Disease 36 

Spread of woody vegetation 36 

Predation 37 

Nests 37 

Young 38 

Adults 39 

Review of natural factors 40 

Artificial factors 40 

Agriculture 40 

Pasture burning 41 

in 



IV CONTENTS 

Limiting factors — Continued. 

Artificial factors — Continued. Page 

Overgrazing 42 

Oil development 43 

Drainage 43 

Pasture mowing 43 

Mechanical accidents 44 

H anting 44 

Management 45 

Protection 45 

Habitat improvement 46 

Evaluating conditions 47 

Census methods 47 

Spring counts on the courtship grounds 47 

Rope count 49 

Car-dog count 52 

Using the census 52 

Spring 53 

Summer 54 

Winter 55 

General recommendations for habitat control 56 

Predator control 57 

Harvesting the surplus 57 

Restocking 58 

Summary 59 

Literature cited 62 

Index 65 



ILLUSTRATIONS 



Plate Facing page 

1. Attwater's prairie chickens (Tympanuchus cupido attwateri) on boom- 

ing ground Frontispiece 

2. Dense cordgrass areas in Aransas County, Tex 4 

3. Male Attwater's prairie chicken, showing vocal sacs 10 

4. Nest and eggs of Attwater's prairie chicken; Colorado County, Tex__ 14 

5. Concealment of nests by Attwater's prairie chicken; Colorado County, 

Tex 15 

6. Chicks of Attwater's prairie chicken; Colorado County, Tex 16 

7. Wild indigo (Baptisia) in a closely grazed pasture; Austin County, 

Tex 22 

8. Diversified cover — excellent prairie chicken range; Colorado County, 

Tex 30 

9. Medium-heavy to heavy cover — excellent food-cover conditions in a 

moderately grazed pasture; Colorado County, Tex 31 

10. Shells of eggs at prairie chicken nest destroyed by house cat; Colorado 

County, Tex 38 

11. Native bluestem prairie — well populated by prairie chickens; Colorado 

County, Tex 39 

12. Excellent unburn ed cover at right of road; inferior burned cover at 

left; Colorado County, Tex 42 

13. Rope counting of prairie chickens on Matagorda Island, Tex 48 

14. Fenced plot planted to hegari; Wharton County, Tex 56 

FiGDHB Page 

1. Distribution of Attwater's prairie chickens in Texas 3 

2. Movements of a combined brood, Colorado County, Tex 23 

3. Rainfall conditions in May in the range of Attwater's prairie chicken in 

Texas Facing page 34 

4. Diagram of the rope count 50 

V 



ATTWATER'S PRAIRIE CHICKEN 

By Valgene W. Lehmann 
Collaiorator, Division of Wildlife Research, Fish and Wildlife Service^ 



INTRODUCTION 

Attwater's prairie chicken {Tympanuchus cupido atticateri Ben- 
dire) (see frontispiece), might well be called the heath-hen of the 
South. It is so closely related to the now extinct heath-hen {T. c. 
cupido) of northeastern North America as to be classified in the 
same species. Like the heath-hen, Attwater's prairie chicken once 
inhabited a large area, its former range including the coastal tall- 
grass (Andropogon) prairies of southwestern Louisiana and in Texas 
west and south to Cameron County, near Port Isabel. In certain 
areas the birds were abundant. Old-timers report that the deep 
booming courtship calls of the males once reverberated from the 
prairies with such force and monotony as actually to pain sensitive 
eardrums. The bird, however, is no longer abundant. It has de- 
creased in numbers as man has exploited its habitat until now it is 
threatened with the fate of the heath-hen — extinction. 

In his "Biological Survey of Texas" Vernon Bailey (1905: 19)' 
places Attwater's prairie chicken at the head of the list of breeding 
birds of the Texas coastal prairie. In addition to being a character- 
istic bird of the region, this prairie chicken is probably the most 
popular species wherever found. Most people who know it have a 
genuine appreciation of its color and charm. Rare indeed is the 
person who finds no esthetic stimulus in the sight of a strutting 
male on the booming ground, or a brood of downy chicks on the edge 
of a short-grass flat. Both ranchmen and farmers highly appreciate 
the prairie chicken's appetite for grasshoppers, salt-marsh cater- 
pillars {Estigmene acraea)^ and the moths of the cotton leaf worm 
{Alabama argillacea). Under proper conditions prairie chicken 
hunting provides a high type of sport, and the flesh of the birds, 
especially that of the young, is highly esteemed as food. 



1 Cooperative contribution from the Texas Cooperative Wildlife Research Unit, estab- 
lished by the Agricultural and Mechanical College of Texas ; the Texas Game, Pish, and 
Oyster Commission ; the American Wildlife Institute ; and the Fish and Wildlife Service. 

* Publications referred to parenthetically by date (alone or followed by colon and specific 
page) are listed in the Literature Cited, p. 62. 

Explanation of Fkontispiecb 

Attwater's prairie chickens (Tympanuchus cupido 
attwateri) on booming ground 



2 NORTH AMERICAN FAUNA 5 7, FISH AND WILDLIFE SERVICE 

The real appeal of the prairie chicken, however, lies in its con- 
nection with the colorful and eventful early days in Texas. The 
prairie hen summons memories ; it prompts old-timers to recall when 
the range was free of wire fences and oil derricks, and rich grasses 
grew waist high. Thoughtful people deplore the passing of Att- 
wat^r's prairie chicken, one of the last landmarks of the prairie as 
it used to be. Highly appropriate was the selection of this bird as 
a species of major interest by the Texas Cooperative Wildlife Ke- 
search unit.' 

FORMER DISTRIBUTION OF PRAIRIE CHICKENS IN TEXAS 

H. C. Oberholser, in a letter to the present writer, states that in 
his opinion prairie chickens once occurred at some time of year on 
most prairie areas in Texas. In the main it appears that the differ- 
ent kinds of prairie chickens in the State occupied separate ranges, 
and that mixing and intergradation were confined largely to marginal 
areas. 

The principal former range of the greater prairie chicken in Texas, 
as indicated by the records of F. M. Bailey (1927: 130), Gross (Bent 
1932: 262), Strecker (1927: 321), and old residents with whom the 
writer has conferred, was northeastern Texas southwest to the vicin- 
ity of Waco. Likewise, records show that the lesser prairie chicken 
was indigenous to northwestern Texas and the high plains region 
in winter to about Bandera and westward through the "hill country" 
to the arid plains west of the Pecos River (Bendire 1892: 355, and 
others). Attwater's prairie chicken, it appears, was largely confined 
to the better-drained prairies of western Louisiana and Southeastern 
Texas (fig. 1, p. 3). 

According to Oberholser (1938: 190-191) the eastern limit of the 
range of Attwater's prairie chicken was in the vicinity of Abbeville, 

* So many persons have assisted in the prairie chicken studies that it is impossible to 
list them all. General supervision of the work was by Walter P. Taylor, leader of the 
Texas Cooperative Wildlife Research Unit, College Station, Tex. Valuable editorial 
suggestions were received from W. B. Davis, professor of wild game. School of Agriculture, 
Agricultural and Mechanical College of Texas; and from William J. Tucker, executive 
secretary, Texas Game, Fish, and Oyster Commission. The bulk of examinations of crops, 
gizzards, and scats was done by Clarence Cottam, Clarence F. Smith, and their associates 
in the Section of Food Habits, Division of Wildlife Research, Fish and Wildlife Service. 

In his field work in 1938 the writer was assisted by H. R. Siegler, field biologist of the 
Research Unit. Many Colorado County landowners cooperated ; among these, M. C. 
Shindler, Emil Gleuck, Ed Koy, Adolf Renz, and I. V. Duncan deserve special mention. 
E. P. Haddon, photographer of the Texas Commission, took some of the photographs here 
reproduced. The assistance of the State game wardens was indispensable. Deserving 
of special mention are T. S. Boothe, Beaumont ; J. C. Gardner, Hull ; R. Z. Cowart, Rosen- 
berg; Ed McCloskey, Victoria; C. D. Tidwell, Bay City; G. P. Ferguson, Sinton ; and 
T. T. Waddell, Eagle Lake. Waddell's contributions to the study were outstanding; he 
gave most generously of his time, records, and extensive experience. To him, and to all 
others, the writer is deeply grateful. 



ATTWATER'S PRAIRIE CHICKEN 



Opelousas, and Bayou Teche in Louisiana. There are no authentic 
records of the occurrence of any species of prairie chicken in Texas 
south of northern Aransas County, except for one bird reported 
from near Brownsville by Merrill (1879: 159-160). Prairie chickens 
did not occur near San Antonio, Tex., in 1890, for Babbitt, in Bendire 
(1894: 130) wrote as follows: "The prairie hen is not found in the 




LEGEND 

Probable Former Ranqe 
Prcaenf Pange 



Figure 1.— Present distribution of Attwater's prairie chicken in Texas and 
probable former range in the coastal section. 

immediate vicinity of San Antonio, Tex., but exists in great numbers 
south and southeast from here, all at an average distance of 100 
miles. * * *" Simmons (1925: 82) submits the records of O. 
Brinkman and C. D. Oldright as evidence that Attwater's prairie 
chicken occurred as a breeding bird in the vicinity of Austin. Travis 



4 NORTH AMERICAN FAUNA 57, FISH AND WILDLIFE SERVICE 

County, and in Williamson County as late as 1878, but the accuracy 
of the data is questionable. Apparently the limit was the northern 
edge of the coastal prairie. 

Roughly, the territory occupied by Attwater's prairie chicken was 
south of a line extending northeast from Refugio through Fannin, 
Thomaston, Provident City, Rock Island, Industry, Welcome, Bell- 
ville, Prairie View, Tom Ball, Humble, Liberty, Devers, Cheek, and 
Orange. All this area of approximately 8,500,000 acres in coastal 
Texas, however, was not occupied. Deciduous woodlands near rivers, 
as along the San Antonio, Guadalupe, Colorado, Brazos, and 
Trinity, were used only to a limited extent and only along the mar- 
gins. Prairie chickens did not occupy the pine forests in Harris 
County and to the east or the thick mesquite-acacia brush that oc- 
curred in considerable stands in Calhoun and other western counties 
as much as 100 years ago. Brackish and salt-water marshes in Or- 
ange, Jefferson, and Chambers, and less widely in other counties 
to the west, and extensive cordgrass {Spartina spartinae) flats (pi. 2) 
in Aransas County and elsewhere in low country bordering the Gulf, 
probably always were little used by chickens except to a limited 
extent in winter. There were, however, about 6,000,000 acres of 
bluestem prairie that probably supported many prairie chickens in 
favorable years. 

DIFFERENCES BETWEEN ATTWATER'S AND THE OTHER PRAIRIE 

CHICKENS 

During the nineteenth century three kinds of prairie chickens oc- 
curred in Texas: the greater prairie chicken {Tympanuchus cupido 
americanus Reichenbach), Attwater's prairie chicken {T. c. attioateri 
Bendire), and the lesser prairie chicken {T. pallidicinctus Ridg- 
way). Differences between the greater and Attwater's prairie chick- 
ens are slight; the lesser prairie chicken is somewhat better 
characterized. 

ATTWATER'S PRAIRIE CHICKEN 

Bendire (1894: 130) described Attwater's prairie chicken as — 

Smaller than T. americanus [greater prairie chicken], darker in color, more 
tawny above, usually with more pronounced chestnut on the neck ; smaller 
and more tawny light colored spots on the wing coverts, and much more 
scantily feathered tarsus, the latter never feathered down to the base of 
toes, even in front; a broad posterior strip of bare skin being always exposed, 
even in winter, while in sximmer much of the greater part of the tarsus is 
naked. 

In weight Attwater's prairie chicken, however, is not perceptibly 
lighter than the greater prairie chicken. The average of 10 males 
(33.11 ounces, as shown in table 1, p. 5) exceeded by 2.11 ounces 
the average weight of the greater prairie chicken (31 ounces), as 



North American Fauna 57. Fish and Wildlife Service 



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ATTWATER'S PRAIRIE CHICKEN 



given by Gross (1930a: 40). The average weight of six females 
(25.7 ounces) was only 0.6 ounce less than that of the female greater 
prairie chicken (26.3 ounces), according to the same authority (loc. 
cit.). The weight of Attwater's prairie chickens, especially that of 
males, varies perceptibly from season to season ; three males obtained 
at the beginning of the courtship season were appreciably heavier 
(about 7.5 ounces) than those collected at other times. Darkness of 
color, tawniness above, and the amount of chestnut on the neck are 
other characters that vary greatly both seasonally and individually. 
Winter specimens are generally lighter in color than those collected 
in spring; they have comparatively little chestnut on necks and 
backs. The feathering on the tarsus also varies with the season ; the 
legs of specimens collected in winter are well feathered to the base 
of the toes. The style of barring on the back and rump, according 
to F. M. Bailey (1927: 130), is the same for both subspecies, that is, 
the bars are single, broad, and solid black. Altogether, physical 
differences between Attwater's and the greater prairie chicken are 
minor and insufficient to allow accurate field identification. In a 
series of skins, however, the smaller measurements of wing, tail, bill, 
and total length and the differences in general ruddiness and buffiness 
of the underparts are characteristic and serve to separate Attwater's 
prairie chicken as a subspecies. 

Tabui: 1. — Weights of 16 Attwater's prairie chickens 



County 


Date collected 


Weight I 


County 


Date collected 


Weight 1 


Grams 


Ounces 


Grams 


Ounces 


MALES 

Colorado 

Do - 


Apr. 17, 1939 2 
Sept. 1,1937 3 
Sept. 4,1937' 
Oct. 23,1937 
Nov. 3,1937 

Jan. 6, 1938 
Jan. 27,1938 
Feb. 14,1938 


1, 135. 20 
682. 00 
590. 07 
760.20 
874. 00 

723. 69 
715.24 
726.80 


40.03 
24.05 
20.81 
26.81 
30.82 

25.18 
25.22 
25.63 


MALES 

Refugio 

Do 

Colorado 


Feb. 15,1938 

do 

Mar. 18, 1938 
Apr. 10, 1938 < 
July 26,1938 

Feb. 15,1938 
Aug. 20,1938 
Aug. 23,1938 


1, 103. 70 
1, 125. 20 
1,120.45 
1, 077. 26 
921. 34 

785. 60 
722. 89 
708. 72 


38.92 
39 68 


Do.- 


39 51 


Do 


38.00 


Do 


Colorado 

FEMALES 

Refugio 

Colorado 

Do 


32 50 


FEMALES 

Colorado 

Do - 


27.70 
25.50 


Austin- 


25.00 









1 Average weights: Males, 938.94 gm. (33.11 oz.); females, 730.49 gm. (25. 70 oz.). 

' Taken from hawk. 

' Immature bird. 

* Taken from poacher. 

LESSER PRAIRIE CHICKEN 

The lesser prairie chicken is somewhat smaller than either of its 
relatives. Verne E. Davison, in a letter, reports that 20 mature males 
from Oklahoma weighed 23.50 to 31.50 ounces and averaged 27.56 
ounces. Five hens weighed 23.75 to 27.50 ounces and averaged 
25.55 ounces. In other words, these male lesser prairie chickens were, 
on the average, 3.44 ounces lighter than the male greater prairie 
chickens (31 ounces) weighed by Gross (1930a: 40); these female 



6 NORTH AMERICAN FAUNA 57, FISH AND WILDLIFE SERVICE 

lesser prairie chickens weighed 0.55 ounces less than the female 
greater prairie chickens that Gross obtained. According to Bailey 
(1927: 131), the general coloration of the lesser prairie chicken is 
paler than that of either the greater or Attwater's, and the color 
and arrangement of the bars on back and neck also differ. Wliereas 
the bars are single, broad, and solid black in both the greater and 
Attwater's forms, they are treble, a broad brown bar enclosed by 
two narrow black ones, in the lesser species. 

FORMER ABUNDANCE OF ATTWATER'S PRAIRIE CHICKEN 

Accurate information as to the former abundance of Attwater's 
prairie chicken is difficult to obtain, although the data at hand 
record their numbers in certain areas. Many old cattlemen of the 
coastal prairie have told the writer that in early days the prairie 
chickens were relied upon to furnish fresh meat for the cattle camps. 
The task of killing 40 or 50 prairie chickens was menial, the cook of 
the outfit usually attending to it. 

In the Eagle Lake area, Colorado County, not more than 35 years 
ago, prairie chickens were shot as clay pigeons are today. On ap- 
pointed occasions parties of 10 to 20 or more men encamped in the 
sandhill country along the Bernard River and hunted the birds for 
periods varying from a few days to a week or more. At the end 
of each day the chickens killed, or their heads, were tallied. At the 
end of the encampment period the party having killed the smallest 
number paid the expenses of the outing. Waddell and others state 
that 10 or more piles of prairie chickens, each containing upwards 
of 100 birds, usually were left at the camp sites to rot or to be eaten 
by vultures. These encampments began about July 4 and continued 
through fall and winter. 

During the summer of 1893 or 1894, in Matagorda County, near 
Bay City, V. L. LeTulle reports that 71 Attwater's prairie chickens 
were shot in 2 hours; and that in 1895, at the site of the present town 
of Van Vleck, he and 3 friends killed 72 birds in an afternoon, and 
except for poor marksmanship would have bagged many more. 
Near Wharton, in Wharton County, in the fall of 1894 or 1895, 
LeTulle found 340 piled where hunters had camped. 

Mendell Burrell of the Ray Pipkin ranch (Big Hill country, 
Jefferson County) told the writer that as late as 1920 his domestic 
chickens were fed under the ranch house in winter to prevent prairie 
chickens from consuming the grain. In the same area it is said that 
flocks of from 150 to 200 Attwater's prairie chickens often alighted 
in the introduced chinaberry trees {Melia azedarach vmbraeulifera) 
around the ranch houses and fed extensively on the berries. In 
verification of this statement W. S. Boothe, State game warden at 



ATTWATER'S PRAIRIE CHICKEN 7 

Beaumont, Tex., presented the writer with a photograph, taken in 
1910 on the White Ranch at Devers, showing a dozen prairie chickens 
in a chinaberry tree beside a house. 

C. H. Brosig, who hunted Attwater's prairie chickens in the Eagle 
Lake area for more than 40 years, reported that the birds once 
were so numerous in the sandhill country bordering the Bernard 
River that a new covey frequently was flushed while singles from 
one previously discovered were being pursued. Paul Mundelius noted 
a similar high density in concentrations of prairie chicken^ in the 
Sealy-San Felipe section in the eastern part of Austin County in 
1873-75. These conditions are seldom found on areas where the pop- 
ulation is less than one bird to an acre, and they show the former 
abundance of Attwater's prairie chickens in favorable areas. Not 
all the coastal bluestem {Andropogon) prairie, about 6,000,000 acres, 
wag equally favorable for prairie chickens even under pristine con- 
ditions; well-drained, well-populated country (one bird to an acre), 
as along the Bernard River, did not aggregate more than 900,000 
acres, or about 15 percent of the inhabited range. A little more than 
half, 3,300,000 acres, or 55 percent, of the prairie country was only 
fairly well drained ; these areas, protected for periods up to 17 years, 
now have a maximum population of about one bird to each 10 acres. 
Approximately 1,800,000 acres, or 30 percent, was poorly drained; 
prohibition of hunting for periods up to 15 years has not produced 
a population in excess of one bird to each 50 acres on certain of 
these large ranches. Probably, therefore, the former abundance of 
Attwater'g prairie chicken in Texas approached, but seldom if ever 
attained or exceeded, 1,000,000 individuals, even in peak years. 

PRESENT DISTRIBUTION AND NUMBERS 

Data on the present status of Attwater's prairie chicken (table 2, 
p. 8) were obtained as follows: 

At least 90 percent of all farms and ranches known or thought 
to have been occupied by the birds in 1937 were visited by the writer 
in company with local State game wardens. Unless the warden was 
thoroughly familiar with conditions on the various areas, conference^ 
were held with landowners, managers, cowboys, guides, hunters, or 
other persons who were in position to know the status of prairie 
chickens on particular tracts. After the conferences a general recon- 
naissance of the areas wa^ made by automobile or on horseback, and 
notes were taken on the topography, vegetation, surface water, and 
soil to ascertain the general suitability of the land for prairie chickens, 
as was done in similar studies previously made in the Eagle Lake area. 

Then in the light of all available information the range of Att- 
water's prairie chicken was mapped in each county, and representa- 



8 NORTH AMERICAN FAUNA 57, FISH AND WILDLIFE SERVICE 

tive sample areas were selected for intensive study. The birds were 
then "rope counted" * on the sample tracts. Finally, the total popu- 
lation of the area was estimated from the data obtained by counting 
the sample plots. 



Tarle 2. — Population status of 


^he Attivater's prairie chicken in Texas 


(1937) 




Size of 
tract 


Census area 


Territory occupied 
per bird 


Popula- 
tion of 
■whole 
tract 


County 


Size 


Popula- 
tion (rope 
count) 


Census 
area 


Whole 
tract 




Acres 


Acres 
1,080 
530 


Number 

56 

106 


Acres 
19.2 
5.0 


Acres 


Numhtr 


















Total or average (1) ' 


42,000 

6,554 
5,000 


1,610 


162 




9.9 


4,242 












3 25 


Goliad ^ 










34 














Total or average (2) - 


11,554 




























f 


230 
873 
218 


4 
14 



57.5 
62.3 

















1 
















Total or average (3) 


65, 535 


1,321 


18 





__ 73. 4 


892 




4,000 

4.915 
IS, 022 
49, 152 


























4,200 
14,250 


32 
315 


131.2 
45.2 




















76, 089 


18,450 


347 




53.1 


1,433 


























736 





















Total or average (5).. 


12, 288 


736 









550 




f --- 


542 
364 
219 

1.57 
716 

482 


4 


1 
3 




135.5 












Harris -- 


\- 


219.0 
52.3 








1 






Waller 




























Total or average (6) -.- 


103, 878 


2,480 


8 




310.0 


335 








f 


585 
248 
269 
334 


29 
2 
1 
2 


20.1 
124.0 
269.0 
167.0 








1 






Brazoria 










1 




























Total or average (7) 


54. 067 


1,436 


34 




42.2 


1,281 












4,000 
700 
400 


24 

1 



166.6 
700.0 
































Total or average (8) 


91, 724 


5,100 


25 




204.0 


449 








Grand total or average 


457, 135 


31, 133 


594 




52.4 


8,711 









I Counties in which prairie chickens occur but in which counts were not made because of scarcity of birds 
or similarity of the areas to adjoining counties. 
' Numbers in parentheses in total lines refer to areas correspondingly numbered in the map, fig. 1, p. 3. 
' Estimates supplied by game wardens. 



* For an account of the method used in rope counting see p. 49. 



ATTWATER'S PRAIRIE CHICKEN 9 

The known range of Attwater's prairie chicken in Texas, as of 
September 1937, aggregated only 457,135 acres, as compared with 
approximately 6,000,000 acres in former times. The range has there- 
fore been reduced more than 93 percent during the past 100 years or so. 
The birds are still to be found in the counties of Aransas, Kefugio, 
Goliad, Victoria, Calhoim, Dewitt, Jefferson, Waller, Galveston, 
Chambers, Liberty, Lavaca, Wharton, Colorado, Matagorda, Austin, 
Fort Bend, Harris, Brazoria, and possibly Jackson and Orange, 
although they have not been reported by reliable observers in the 
last two for several years. They have definitely been extirpated 
from Willacy and Montgomery Counties, and their distribution has 
become restricted throughout the State, especially in the counties 
of Goliad, DeWitt, Lavaca, Calhoun, Matagorda, Galveston, Fort 
Bend, Liberty, Jackson, and Orange, if they occur there at all. 
Prairie chickens had not been seen in Goliad County for at least 
10 years prior to 1937, at which time four birds were reported on 
the W. J. O'Conner ranch. 

No more than half the grassland range in any county except 
Refugio is occupied by prairie chickens. In the counties of Mata- 
gorda, Lavaca, Wharton, Calhoun, Liberty, Jackson, and Fort Bend 
even less than 10 percent of apparently satisfactory pasture is inhab- 
ited. Roughly, the available range for prairie chickens is only about 
30 percent occupied and, with the exception of about 20,000 acres 
in southeastern Refugio County, all the occupied area has a sparse 
population. 

The total number of prairie chickens in coastal Texas in the 
summer of 1937 was only about 8,700. The estimated 1937 popula- 
tion was probably less than 1 percent of the number believed to 
have occupied the coastal prairie in peak years before it was devel- 
oped by white men. Approximately 4,200 chickens (or almost 50 
percent of the known population of the State) inhabit two ranches 
in Refugio and Aransas Counties. The estimated population of 
4,500 birds for the remainder of Texas is small indeed ! 

The consensus is that, during the past 10 years, the number of 
prairie chickens has decreased in all coastal counties except Refugio 
and Brazoria. In Refugio County there has been a rapid increase 
in recent years, probably largely because of excellent protection on the 
Salt Creek and Martin O'Conner ranches. Since 1935 the birds have 
spread from these onto the O'Brien, Powers, Welder, and Heard 
ranches near Greta, Refugio County, and probably also into Goliad 
County. Because of protection during a 5-year close season in 
Brazoria County (1932-36), R. Z. Cowart, State game warden there 
believes that in 1937 the number of birds had reached and possibly 
slightly exceeded the 1927 population level. 



10 NORTH AMERICAN FAUNA 5 7, FISH AND WILDLIFE SERVICE 

The prairie chicken population of the counties of Orange, Liberty, 
Fort Bend, Matagorda, Jackson, Lavaca, Calhoun, and Goliad, where 
populations of less than 100 birds per county obtain, may already be 
reduced to the point where recovery will be extremely difficult or 
even impossible. So long as any birds remain, however, every effort 
should be made to build up their numbers. 

HABITS 

COURTSHIP AND MATING 

Prairie chickens do not pair for breeding, but are promiscuous. 
Males occupy selected courtship stations on booming grounds (see 
frontispiece) , which are visited by the females. Copulation may take 
place elsewhere, however, in case of chance meetings. To attract the 
females, the cocks put on elaborate exhibitions, and their courtship 
antics are unbelievably weird. Of special interest is the manner 
in which the booming call is rendered. 

This call of the male resembles somewhat the sound whur-ru-rrr^ 
with strong accent on the second syllable. Although it generally 
lasts about 5 seconds, the call varies in length and tone. In mid- 
season the calls are characteristically deep and full-throated; later 
they become shorter and higher pitched, possibly because the males 
are then less vigorous. The sound of the booming carries for a 
mile or more on quiet days. It has a ventriloquial effect and often 
seems farther away or closer than it actually is. During the court- 
ship season males boom regularly in early morning (sunrise until 
about 8 a. m.) and in late afternoon (5:30 p. m. until sunset), but 
calls have been heard at all hours of the day and night. Booming 
at night is sporadic, however, even during the peak of the courtship 
season in March, being most common when the moon is bright and 
when there is little wind. 

The appearance of the male, while booming, is striking. As a 
preliminary to uttering the call he stretches his neck forward par- 
allel to the ground. The erected pinnae, or neck tufts, point for- 
ward; the spread tail is held vertically or even inclined slightly 
over the back. The wings are extended downward and held firmly 
against the body and legs, the primaries almost touching the ground. 
The whole body appears strained and rigid. A short run forward is 
followed by vigorous stamping with the feet, which lasts only a few 
moments, but which under favorable conditions is distinctly audible 
for 50 feet or more. Inflation of the air sacs, which are actually 
but one sac with two lateral portions (pi. 3) is synchronized with 
the stamping. The first syllable of the booming is given before 
stamping ends, the male quickly jerking his head downward as he 
begins the call and keeping it there until the air sac is deflated. 



North American Fauna 57. Fish and Wildlife Service 



Plate 3 







Male Attwater's prairie chicken, showing vocal sacs. (Photo from Texas Game, 
Fish, and Oyster Commission.) 



ATTWATER'S PRAIRIE CHICKEN 11 

The call of Attwater's prairie chicken apparently is given in the 
same manner as was that of the extinct heath-hen, its near relative. 
Gross (Bent 1932: 272) describes the booming mechanism of the 
heath-hen as follows : 

The sacs do not produce the notes, as was thought by some of the earlier 
ornithologists, but have much to do with modifying the sounds produced by 
the syrinx (the vocal mechanism at the juncture of the bronchial tubes). The 
sounds are produced by the air forced from the lungs, which vibrate specialized 
membranes of the syrinx under control of a complex set of muscles. The 
sound waves then issue through the trachea and glottis to the pharynx. In 
the production of such notes as the ordinary cackle the mandibles are opened 
and the air accompanied by the sound waves issues out of the mouth. In the 
tooting [booming] performance the mandibles are tightly closed, the throat 
patch is elevated, and the tongue is forced against the roof of the mouth 
(palate) by the mylohyoides muscles, which close off the exit through the 
internal nares. The tongue is bent in such a way that it causes the glottis at 
the base of the tongue to open directly in front of the esophagus. The air 
now coming from the respiratory system is forced to fill the modified anterior 
end of the esophagus, or gullet, which becomes distended like a balloon. While 
the air sac is filling, the sound waves produced by the syrinx beat against 
these tense drumlike membranes, which serve as resonators for the sounds 
and give them their great carrying power. 

The booming call does not complete the vocabulary of male prairie 
chickens at courtship time. The rendition of additional calls, all 
distinctly henlike, is described as closely as possible on p. 12. On 
windy days cackling sounds, like Nos. 1, 2, and 3 in the list, carry 
farther than booming. The call note piooih (No. 14) dominates 
when hens visit the courtship grounds. Observers may identify 
grounds where females are present by this piuoik call. 

Males do not confine their courtship activities to vocalizing, and 
fights are common. Opponents usually approach each other, utter- 
ing peculiar whining notes, with necks outstretched, ear tufts erected, 
tails spread, wings drooped, and air sacs deflated. Then, as if pos- 
sessed of the same thought, they suddenly hop off the ground, wings 
beating rapidly, and clash in midair. These bouts are usually dis- 
continued after three or four flurries, and the victors seem satisfied 
after pursuing their opponents for short distances. Many feathers 
are frequently lost, but fights seldom if ever end fatally. Males 
sometimes engage fancied opponents, as clumps of weeds or tufts 
of tall grass, and at other times they joust and bluff for periods up 
to 30 minutes or more without striking a blow. With necks out- 
stretched, heads held a few inches apart, and wings dangling loosely, 
they resemble domestic roosters fighting. At intervals males flutter 
into the air to heights of 3 to 5 feet, alighting nearly on the spot 
whence they arose. Their surplus energy apparently must be expended 

303807°— 41 2 



12 NORTH AMERICAN FAUNA 5 7, FISH AND WILDLIFE SERVICE 

in one way or another, although activity sometimes lags for brief 
periods. 

CAIX OF MALE PRAIEEE CHICEIONS ON COXJBTSHIP GROUNDS 

1. Ca-ca'-carca-ca-ca-ca-ca-caa-caa—. All except last two notes given rapidly, 

2. Ca-ca'-caa, ca-ca'-caa Rapid. 

3. Ca-ca-ca-ca'-ca Rapid, accent on second to last syllable. 

4. Ca-ca-ca-ca-keece All except last syllable given rapidly. 

5. Kmeee, ca-ca-ca-oa-ca-ca First syllable dravpn out, remainder given 

rapidly. 

6. Kwerr-kwerr-pwah First two syllables drawn out. 

7. Kwier-kwier-ku-ier-kicier All syllables drawn out. 

8. Pwark or pwarrk Medium rapid. Often preceeds cackling 

or booming, carries as far as or farther 
than booming notes under certain 
weather conditions. 

9. Caaa-caaa-caaa-caaaa Slow and drawn out. Sounds almost ex- 

actly like protests of a domestic setting 
hen that is disturbed. 

10. Pwiek, pwark Medium rapid. 

11. Pwiek, pwiek, pwiek All notes drawn out with emphasis on 

the iek. 

12. Pwiek, ca-ca-ca-ca-ca-ca<i Pause after first note, cackle given rapidly. 

13. Pwk-pwk-pwk-pwk-pwk-pwk Har.sh notes executed rapidly, but in a 

subdued tone. 

14. Pwoik, pwoik, pwoik, pwoik Executed rapidly and with much vigor. 

These notes predominate all other calls 
when a female approaches a courtship 
ground. 

15. Kliee, kliee, kliee; ca-ca-ca-ca— Kliee's drawn out ; ca's given rapidly. This 

is a prominent call in early spring. 

16. Kwoo, kiooo; kwah, kwah Rapid. Another prominent early season 

call. 

The performers do considerable feeding when they first arrive on 
the courtship ground, and certain of them feed sporadically throughout 
their stay. At other times individuals, sometimes an entire group, sit 
or stand in their places and look about. Rest periods terminate 
abruptly, however, when a male recognizes a real or fancied challenge, 
or when a hen appears. 

While the male is bold and noisy during the mating season, the female 
is demure and shy. Hens visit the courtship grounds irregularly except 
early in March. Even in well-populated territory a week sometimes 
elapses before the persistent male performers are rewarded by female 
company. When on or near a drumming ground, hens usually appear 
little interested in the spirited antics of the obviously excited males. 
Sometimes, however, they walk among the contestants and mate with 
one or several of them. Hens usually remain at the courtship areas 
briefly; usually they stay only a few minutes before leaving to feed 
elsewhere or fly to the vicinity of their nests. 



ATTWATER'S PRAIRIE CHICKEN 13 

In Colorado County signs of the approaching breeding season were 
noted early in January (1937) and late in December (1938) when cer- 
tain males, probably the most vigorous, pecked at and otherwise bullied 
their fellows as the flocks left the roost or fed early each morning. A 
few weeks later, early in February (1937), and late in January (1938), 
males assembled early in the morning on short-grass areas that later 
served as courtship grounds, and fought and maneuvered for choice 
positions. For a week or more, calls consisted largely of miscellaneous 
squawks and cackles, and fights, though frequent, were of short dura- 
tion. Males occasionally attempted to drum or boom, but their notes 
lacked midseason depth and vigor. Females, still in winter flocks, 
seemed indifferent to the proceedings. It was not until February 12, in 
1937, and January 26, in 1938, that booming was commonly heard, and 
each year, after 2 to 3 weeks, flocks of females generally broke up and 
the courtship season was well under way. During both 1937 and 1938 
courtship activity was at its peak in March, continuing through April 
and ending on May 20, in 1937, and on May 21, in 1938, when the last 
booming calls were heard. 

Key areas during the courtship season are the booming grounds where 
males assemble each morning from daybreak until about 8 a. m. and 
each afternoon from 5:30 p. m. until dark and give their courtship 
display. 

The preferred booming ground is a short-grass flat, an acre or so in 
extent, surrounded by an area of medium to heavy grassy cover suitable 
for nesting. Of several hundred sites observed during 3 years (1936- 
38) only one was on ground elevated enough to be termed a small knoll. 
The others were even with or slightly below the adjacent land surface. 
Stoddard (Bent 1932: 245), discussing the greater prairie chicken in 
Wisconsin, says that "the 'cooing' ground [courtship ground] at the 
sandy west end of Sauk Prairie has been used each spring for over 30 
years, the birds always using the same knoll whether in rye, stubble, 
or grown to grass." Courtship grounds of Attwater's prairie chicken 
do not show the same degree of permanence. Cultivation seemingly re- 
sults in immediate eviction, whether the crop is rice, corn, cotton, or 
something else. Likewise, the birds do not use fallow fields except where 
cultivated land is the only other environmental type available, or where 
the fallow land has aged to the extent that its surface and vegetation 
are nearly identical with that of nearby grassland. Even those court- 
ship grounds that are in pastures may or may not be occupied each year 
for a series of years. Of 10 such grounds, on which records were ob- 
tained from 1936 through 1938, only 5, or 50 percent, were occupied each 
year. Their populations were fairly stable (see table 3, p. 14). Of 
the others, 2 were occupied in 1936 and 1937 ; 2 were unused except in 
1936 ; and 1 was occupied in 1936, in part of 1937, and throughout the 
entire season in 1938. There was little variation in the prairie chicken 



14 NORTH AMERICAN FAUNA 5 7, FISH AND WILDLIFE SERVICE 

population of the pastures in which these courtship grounds were situ- 
ated, but in every instance the vegetation on or near the study areas 
varied in density through grazing or burning. Cover changes on and 
near courtship areas influenced their attractiveness to the birds, possibly 
to the point of determining whether they would be occupied and by 
how many individuals. 

Table 3. — Occurrences in S years of male prairie chickens on 5 courtship founds 

in Color-ado County 





Observations 


Birds observed 


Name of pasture 


Extremes 


Averages 




1936 


1937 


1938 


1936 


1937 


1938 


1936 


1937 


1938 


Thomas . - 


2 
2 
2 
2 
2 


11 
8 
14 
13 
20 


6 
6 
6 
11 
12 


7- 9 
9-11 


6- 9 
3-10 


4-11 
5- 8 
3- 8 
5-13 
6-14 


8.0 
10.0 
5.5 
7.0 
7.0 


7.0 
6.0 
8.0 
9.0 
6.0 


8.0 


Do 


7.0 


Do 


5-6 3-9 


7.0 




6- 8 


5-11 


10.0 




7- 7 


0- 8 


10.0 






Total or average 


10 


66 


42 








7.5 


7.2 


8.4 











NESTING 



While the males are still engaged in their courtship performances, 
the females quietly select and improve the nest sites and attend to 
laying, incubating, and hatching the eggs and rearing the young. 
Nests (pi. 4) are made on the ground. Of 19 examined in 1937 
and 1938, 17 were in long-grass pastures, 1 in a hay meadow, and 
1 in a fallow field. All were in dead grass of the previous year's 
growth. Fifteen (about 76 percent) were on or near well-drained 
mounds or ridges, and 4 were in poorly drained situations. In a 
choice of nest sites, cover appeared of more importance than topog- 
raphy and the structure of the soil. Twelve (63 percent) of the 
study nests were situated within 10 yards of well-marked trails, 
possibly because prairie chickens dislike walking through heavy 
matted vegetation when approaching or leaving their nests. Cattle 
make many trails, thereby improving nesting areas. 

Study nests were found always within a radius of half a mile 
to a mile from occupied booming grounds. Sometimes the sites were 
rather distant from acceptable feeding territory, although flights of 
up to a mile seemed to inconvenience the birds very little. 

Nests were merely shallow depressions, about 7 inches in diameter, 
lined with bits of dead grass, twigs, and a few feathers, presumably 
from the females. All were more or less roofed over because of the 
lapping or bending over of surrounding vegetation. Entrances faced 
in various directions with no preference shown. There was consid- 
erable variation in degree of concealment (pi. 5), at least according 
to human standards; 5 nests being excellentl}^, 10 well, and 4 poorly, 
concealed. Kapid new plant growth in April and May aided ma- 



North American Fauna 57, Fish and Wildlife Service 







,^ o 



o O 









■o3 a 
bi o 



^ o 
o3 ;r 



5 



North American Fauna 57. Fish and Wildlife Service 



Plate 5 








^r 



:r ^-/i*^. 




C3 ii 

;^ o S 
5 ^ 00^ 



^O 



ATTWATER'S PRAIRIE CHICKEN 15 

terially in hiding nests ; consequently, some nests that were relatively 
exposed when found were well hidden later. Wild indigo {Baptisia 
sp.), vetch {Vicia litdoviciana) , phlox ( Phlox drummondii) ^ peren- 
nial ragweed {Ambrosia psilostax^hya) ^ dogfennel {Eupatorium sp.), 
and panic grass {Panicum sp.) were green plants that aided con- 
cealment materially by mid-May. In Colorado County, favorite 
nesting materials were dry bluestem grass {Andropogon scoparius), 
and paspalum {Paspalum dilatatuTn). 

The earliest date for a nest containing eggs was reported by Wad- 
dell near Egypt, Wharton County, February 25, 1925; the latest 
record is that of a nest in Colorado County in which the clutch 
was completed May 29, 1938. In both 1937 and 1938, however, the 
peak of the laying season in Colorado County was late March and 
early April. Hens always laid in the morning, usually from 7:30 
to 9, flying to the vicinity of their nests when ready. After cautiously 
looking about or feeding a bit longer, hens walked to the nests and 
remained there for from about 20 minutes to an hour. The laying 
completed, they regularly walked about 20 feet from the nest, scanned 
the landscape, and flew away. Since incomplete clutches were un- 
guarded except during about an hour each day, they were especially 
vulnerable to natural enemies. 

Hens under observation normally laid an Qgg a day until the 
clutch of 8 to 15 was complete, but sometimes they failed to lay for 
periods of 1 to 3 days. Clutches usually contained 12 eggs, and lay- 
ing was generally completed in about 2 weeks. The period of egg 
laying was sometimes extended, however, when nests were destroyed. 
Three hens, each the only resident on a small unburned plot, re- 
nested during 1937, one of them three times. 

New nests, however, were placed 5 to 20 yards from old ones, and 
were less effectively concealed. Destructive agents had even greater 
opportunities to take the later nests, as they did in four out of five 
cases. Since booming ended by mid-May, the period for mating 
was short. Late broods were invariably smaller than early ones, 
probably because late clutches were small, their hatchability low, or 
their mortality heavy. A successful season depends largely on the 
fate of early nests, so that a primary objective of management should 
be to safeguard these attempts. 

Twenty-nine eggs of Attwater's prairie chicken measured by Bent 
(1932: 264) averaged 42.3 by 31.5 millimeters in size, showing ex- 
tremes of 44.9 by 32, 42.4 by 33.5, 38.8 by 28.9, and 39.8 by 28.6 
millimeters. Newly laid eggs were dull cream or bluish buff in 
color, some of them minutely specked with red. During incubation 
the color of the eggs became dull and the shells shiny. Incubation 
began at from 1 day before until 4 days after the last egg was laid. 



16 NORTH AMERICAN FAUNA 5 7, FISH AND WILDLIFE SERVICE 

Except for two feeding and resting periods daily, extending from 
about 7 to 8 a. m. and from 5 :30 to 6 :30 p. m., hens incubated con- 
stantly. When incubation was advanced, morning feeding was fre- 
quently dispensed with. Two clutches pipped approximately 23 and 
24 days after setting began, in each instance requiring about 48 hours 
longer to hatch. Of 71 eggs in 7 nests, only 3 (about 4 percent) 
were infertile, 66 hatching successfully. Seemingly, fertility and 
hatchability are high under favorable conditions. 

The hatching period was evidently a time of danger. Chicks 
peeped incessantly and scrambled in and out of the nest. Nests 
emitted strong odors, apparent even to man. Females at hatching 
time appeared nervous and shifted their positions frequently. Unless 
disturbed, however, they did not leave until the last egg had hatched, 
after which they deserted the nests. In 1937 a nest in which all 
young were hatched by 11 : 50 a. m. on May 15 was vacated by 3 p. m. 
that day, and a brood that was hatching at 8 : 30 a. m. on June 2 was 
gone 24 hours later. One hen left before 2 pipped eggs were hatched 
and before the natal down on some of the young was dry, probably 
because fire ants [Solenopsis) had entered the nest. 

GROWTH AND DEVELOPMENT OF YOUNG 

When leading chicks from the nest, old bird^ traveled through 
the lightest cover or followed trails, probably because heavy matted 
vegetation impeded progress and increased the chance of chicks get- 
ting lost. Cow trails were favorite travel ways. Chicks ranged in 
front, behind, and on both sides of the hen over an area 1 to 6 yards 
in radius. Interruptions for sporadic feeding and for frequent 
brooding, which was probably more necessary for assembling than 
for warming the young, made progress slow. Hens with chicks less 
than 10 days old (pi. 6) seemed mainly concerned with watchfulness 
and brooding. Occasionally they caught available insects or nipped 
off a few green leaves or bud^, but they did little continuous feeding. 
When danger threatened, they gave a warning call, best described 
as a low kwerr^ hwerr^ krcerr, and slowly gkulked through the grass 
with head lowered and wings dangling loosely, almost touching the 
sod. Young birds "froze" with their bodies closely pressed to the 
ground. Decoy efforts of adult females were never so energetic as 
those of bobwhites under similar circumstances. When hens were 
flushed, the chicks in hiding (pi. 6) became impatient after 3 to 5 
minutes, and peeped and ran about in spite of the fact that the object 
of suspicion remained. After the immature birds of 2 to 3 weeks 
of age could fly fairly well, females accompanying them did not 
decoy, but always flushed freely, the young doing likewise. 

Chicks that were less than a week old were brooded quite often, 
probably in all for about 50 percent of the daylight period. Ten birds 



North American Fauna 57. Fish and Wildlife Service 



Plate 6 




Above, Chicks about 10 days old; Colorado County, Tex., approximately 6 miles 
north of Eagle Lake, May 3, 1938. Beloiv, Chicks hiding; Colorado County, 
Tex., approximately 6)4 miles north of Eagle Lake, May 3, 1938. (Photos 
from Texas Game, Fish, and Oyster Commission; E. P. Haddon.) 



ATTWATER'S PRAIRIE CHICKEN 17 

about 2 days old were brooded 42 minutes out of the II/2 hours during 
which they were watched on May 4, 1937. Their position during 
brooding was interesting. Hens squatted low with legs at an angle 
of a.bout 30 degrees with the ground. Wings were drooped and 
feathers of the underparts were ruffled. Some chicks scrambled up 
and under the wings. When the brooding hens were frightened and 
suddenly stood erect, usually only two or three chicks were visible; 
the others, however, tumbled from beneath her wings a few moments 
later. As the chicks grew older, the time spent brooding diminished; 
those 2 weeks old apparently were brooded little except early in the 
morning, during inclement weather, and at night. 

JsTewly hatched chicks are about the gize of day-old bantams, and 
their coloration is nearly identical with that of young bronze turkeys. 
The basic, buffy yellow is streaked with gray on head and upper- 
parts. Growth and development are rapid. Wing feathers appear 
almost at once; week-old chicks have primaries approximately five- 
eighths of an inch long. Chicks fly when 2 weeks old. Except for 
differences in the length of the tail and legs, they are about the size 
of English sparroWiS. When 3 weeks of age, youngsters are almost 
as large as starlings and can make sustained flights of 40 yards or 
more. At 4 or 5 weeks, young birds approximate the size of mature 
bobwhites, and often fly a hundred j^ards before alighting. When 
6 or 7 weeks old, the young are about half grown and at 8 or 9 weeks 
they are three-fourths the size of adultjs. Youngsters 10 to 12 weeks 
old can scarcely be differentiated from the old birds in the field. 
Weight evidently does not increase as rapidly as size, however, for 
two birds approximately 3 months old were more than a pound lighter 
than mature individuals. 

As young prairie chickens grow in size, all cannot, of course, main- 
tain a brooding position under the sheltering body of the mother. 
Usually by the time they are about 3 weeks old some are forced out- 
side; there they sleep with bodies pressed closely to that of the hen. 
When 4 to 5 weeks of age, two or three chicks sometimes crowd under 
their mother, but the remainder roost from a few inches to about 2 feet 
away. At 6 to 7 weeks, young birds adopt the roosting formation of 
adults. Flocks of Attwater's prairie chickens sleep about a foot or so 
apart, the individuals facing in different directions. Roosting spots 
vary in size from 1 to 3 square yards or more, depending on the number 
of birds in the group. The number of scats left at a roosting site 
is not an absolutely accurate index to the number of birds in a flock, 
because slight shifting of individuals during the night brings about the 
deposition of more than one pile by a bird. 

Chicks about 2 weeks old take vigorous dust baths, a habit that is 
indulged in regularly throughout life when dry, powdery material is 



18 NORTH AMERICAN FAUNA 57, FISH AND WILDLIFE SERVICE 

available. Prairie chickens generally dust during the midday rest 
period that extends from about 10 a. m. to 4 p. m. Old pocket gopher 
mounds and cattle wallows are favorite places. Some birds use the 
same dust bath more than once. 

BROOD SIZE 

The size of the brood generally decreases with the age of the young. 
Of 48 broods on which accurate counts were kept (table 4, below) 6 
from 1 to 3 days old contained 64 young, averaging 10.6 birds each. 
Three broods estimated to be 5 to 10 days old contained only 14 chicks 
averaging 4.6 each. Four broods 15 to 27 days old had 22 young, or 
an average of 5.5. Fifteen families over 4 and under 6 weeks of age 
aggregated 80 young and averaged 5.3. Twenty groups over 6 weeks 
totaled 80 young and averaged 4 each. The average size (5.3 young) 
of 15 families, estimated to be over 4 but under 6 weeks of age, was 
exactly half the average size (10.6) of 6 new broods. The average 
size (5.3) of 15 families over 4 but under 6 weeks old was but slightly 
larger than the average size (4.0) of 20 families older than 6 weeks. 
Therefore, it appears that juvenile mortality is heaviest during the 
first 4 weeks and comparatively light thereafter. 



Table 4. — Size of 'broods and number of chicks counted during May, 

July 


June, and 


County 


Date 


Family 

groups 

observed 


Chicks 

per 
group 


Chicks per 
average 
group 




May 4 
May 15 
May 18 
May 23 
May 28 
May 29 
May 31 


1 
1 
1 
3 
3 
1 
2 


10 

12 

12 

2,4,2 

7, 9, 11 

8 

4,8 


10.00 


Do — 


12.00 


Do 


12.00 


Do 


2.66 


Do 


9.00 


Do 


8.00 


Do - - - 


6.00 






Total or average for May 


12 


89 


7.41 




June 2 
June 3 
June 8 
June 10 
June 24 






4 
1 
2 
2 
3 


6, 9, 4, 2 

10 

3,3 

4,8 

5,4,3 


6.33 


Do 


10.00 


Do 


3.00 


Do 


6.00 




4.00 






Total or aVTS^ge foJ" .Tutia 


12 


61 


5.08 




July 1 
July 8 
July 14 
July 17 
July 19 
July 26 






3 
2 
1 

4 
6 
2 


5,5,6 
3,3 

7 

10, 8, 1, 3 

10, 2, 2, 4, 5, 2 

10,5 


5.33 




3.00 




7.00 




6.00 


Do 


4.16 


Colorado - -- 


8.00 








18 


92 


5. U 




Aug. 12 
Sept. 2 
Sept. 3 
Sept. 4 






1 
3 

1 
1 


3 

5,3,3 

3 

4 


3.00 




3.66 


Do 


3.00 


Do 


4.00 








5 


18 


3.60 










48 


263 


5.48 









ATTWATER'S PRAIRIE CHICKEN 19 

JUVENILE MORTALITY 

Although much remains to be learned about juvenile mortality, 
its causes were fairly well established in some instances. Chicks are 
sometimes trapped and drowned in rice fields at the time of flooding 
(usually about May 10). In 1925, near Egypt, Wharton County, 
Waddell and others picked up hatfuls of chicks and carried them 
beyond the levees. In 1937 a farmer near Eagle Lake similarly res- 
cued a brood. The number of chicks annually saved from this 
hazard, however, is probably insignificant in contrast to those lost. 
Prairie fires kill young and, as stated on page 42, burning is still 
common in certain areas at nesting and brooding time. Unfavorable 
weather, especially rains (pp. 32 to 35) and natural enemies (p. 39), 
account for the death of some young birds, but no small percentage 
of these may be chicks that are lost. 

Chicks stray from the brood more often than one might suspect. 
During April, May, and June, 1937, no fewer than 13 strays were 
seen, all under 4 weeks old. Usually they occurred as singles, but 
sometimes in pairs and trios. How the youngsters became lost, of 
course, was usually unknown, but several reasons were apparent. 
The characteristic loose feeding formation of broods possibly con- 
tributed to straying; also, broods usually scattered widely and flew 
far when disturbed; and, possibly most significant of all, adults did 
not appear to have a highly developed rallying call that doubtless 
would be of assistance in reassembling youngsters. 

Lost chicks evidently join other gi'oups occasionally, as hens ac- 
companied by young of varied sizes were several times noted in 1937. 
Once two chicks, about 2 and 3 weeks old, respectively, were seen 
with two molting males. Higher population levels might increase 
the frequency of adoptions. 

FAMILY DISINTEGRATION 

Many young Attwater's prairie chickens 6 to 8 weeks old leave the 
family groups and take up life on their own, but, as is true with 
domestic chickens, all young do not leave the hen at the same time; 
disintegration of the family group is gradual. Some young remain 
with the hen well into the fall. Unattached young, 6 weeks of age 
or older, as distinguished from lost chicks less than a month old, 
became noticeable late in June and they were frequently seen after 
July. Family disintegration after 6 weeks or thereabouts is normal. 
Young prairie chickens at that age seem as capable of foraging and 
resisting adverse weather as are the adults. 



20 NORTH AMERICAN FAUNA 57, FISH AND WILDLIFE SERVICE 

ANNUAL INCREASE 

The actual survival of young prairie chickens (table 5, below) prob- 
ably is always well below the potential yield (12 or so young from 
each hen) even when favorable weather conditions obtain during 
the critical breeding season. 



Table 5 


. — Young and adult birds observed 


in census after June SO, 1931 




Date 


Area 


Adults 


Young 




County 


Males 


Females 


Sex un- 
known 


Total 


Families 


Strays 


Total 


Brazoria 

Victoria 


July 1 
July 14 
July 17 
July 19 
July 26 
July 27 
Aug. 12 
Sept. 1 


Acres 
585 
921 

1,080 
530 

1,450 
851 

1,282 

2,000 


Number 
2 
1 
1 
3 

2 
1 
1 


Number 
4 
1 
4 
8 
2 

1 
5 


Number 
2 
6 
23 
53 
4 
2 
2 
8 


Number 
8 
8 
28 
64 
6 
4 
4 
14 


Number 

5.5,6 

7 

10, 8, 1, 3 

10, 2, 2, 4, 5, 1 

11,5 

3 

3 

5,3,3 


Number 

1,1,1,1,1 

1,2 

2,1,1,1,1 

1, 1, 2, 1, 1, 1 

2.3 

1 

1 

1, 2, 1. 3 


Number 
21 
10 


Refugio 


28 


Do 


32 


Colorado. 

Brazoria 

Harris 


21 

4 
4 


Colorado 


18 


Total 


8,699 


11 


25 


100 


136 


103 


35 


138 









In a rope count on or after July 1, 1937, 138 young as compared 
with 136 adults (about 1:1) were enumerated on an area of more 
than 8,699 acres. At this time most of the counted birds were 4 
weeks old or more and were beyond the age when mortality is thought 
to be most severe. The increase on the counted areas, then, was only 
about 100 percent in spite of the fact that food, cover, and weather 
conditions were favorable. A 100 percent increase of prairie 
chickens in any one year is very good, and the arguments for long 
open seasons and large bag limits, based on the potential annual 
increase (12 chicks for each hen, or about 600 percent a year), evi- 
dently are fallacious. 

FLOCKING 

Late in summer and early in fall, the prairie chickens displayed no 
marked tendency to combine into stable groups. In August and 
September of 1936 and 1937 well over half the birds observed in 
Colorado County were recorded as singles, pairs, and trios, although 
small groups of 4 to 6 were not uncommon. Occasional larger flocks 
were recorded, but these appeared to be temporary. In Colorado 
County, at about noon on September 1, 1937, a flock of 15 to 25 birds 
was noticed in a cotton field. On the following 3 days at the same 
hour 11, 15, and 9 birds, respectively, were present in that field; 
but they had come in between 9 : 30 and 11 : 30 as singles, pairs, and 
in small groups not exceeding 5 birds each. Between 4 p. m. and 
dark they left the field as they had come. Again in Colorado 
County, at 6 p. m. on September 3, 1937, another group of 16 birds 
found in a pasture came together as follows ; At 5 : 40 p. m. a group 



AtTWATER'S PRAIRIE CHICKEN 21 

of 8 flushed approximately 1 mile from the spot where the large 
flock was later noted, and as they flew over the prairie, a pair, a 
single, a trio, and another pair joined the original group. All set- 
tled and fed together for a time, but the bevy disintegrated by dusk. 
Like instances suggest that early fall flocks of a dozen or so birds 
are unstable groups brought together largely by chance. 

In fall, after the weather turned cool, groups of prairie chickens 
became the rule rather than the exception. Early November bevies 
generally contained 4 to 12 birds each, but large flocks became in- 
creasingly common from about December 1 to the onset of the breed- 
ing season. Late in winter (January) Guy Ferguson, State game 
warden, Sinton, Tex., observed flocks in Refugio and Aransas Coun- 
ties that contained more than a hundred birds. Wardens Waddell 
in Colorado, Austin, and Wharton Counties, and McClosky in Vic- 
toria County, reported winter aggregations of about the same size. 
In 1936, J. O. Linney, foreman, Salt Creek (Hallahan) ranch, Re- 
fugio and Aransas Counties, noticed late winter concentrations esti- 
mated to contain 250 to 300 individuals. The writer has not observed 
such large winter flocks, possibly because he has not made observa- 
tions in areas where the birds were suflficiently numerous. January 
assemblages of 25 to 35 birds were not uncommon, however, in Colo- 
rado County. Despite the fact that large flocks became more fre- 
quent from November until the breeding season, small groups of 8 
or fewer birds or singles were always to be found. All packs ob- 
served in Colorado County late in November, December and January 
contained birds of only one sex. Late in January, residents of the 
coastal country eagerly listen for the first booming calls, which, 
besides promoting rapid disintegration of winter flocks, signal the 
departure of winter and the coming of spring. 

seasonal movements 
Spring 

Comprehensive data on prairie chicken movements are lacking, but 
the records obtained in 1937 are of interest. Two broods that were 
observed two or more times daily from the time they were hatched 
until they were 7 and 12 days old, respectively, were, at last observa- 
tion, less than half a mile from the nest sites. Another brood, esti- 
mated to be 8 days old when first discovered on June 2, was within 150 
yards of the same spot at various hours during the next 6 days. A 
fourth brood, about 3 days old on April 29, remained within 400 yards 
of a certain windmill from April 29 through May 31. A 640-acre 
pasture that contained four broods, all under 2 weeks of age when 
rope counted on June 2, likewise harbored four broods 10 days later. 



22 NORTH AMERICAN FAUNA 57, FISH AND WILDLIFE SERVICE 

If this is indicative, the prairie chickens under observation spent 
their first several weeks of life in close proximity to the places where 
hatched. The daily cruising radius of a brood apparently was small, 
seemingly less than 300 yards in the case of birds under 4 weeks old 
in a favorable environment. Some 30 broods observed between May 
1 and June 1 were found in light cover on or near hardpan flats and 
recent burns, indicating a distinct preference for those types of habitat. 

Summer 

An extensive movement involving both young and adult prairie 
chickens in Colorado County began about June 1, 1937, when many 
of the young were 3 to 5 weeks old, and lasted until about June 
30. The sudden scarcity of the birds in places where they had been 
common only a few days before was striking. A 1,000-acre pasture 
that contained 37 individuals (16 old and 21 young) on June 2, held 
only 16 in all on June 10. As the prairie chickens decreased in some 
pastures, they increased in others. A 460-acre pasture that was un- 
occupied on May 1 contained 14 birds on June 8 and 23 on July 26. 
This movement from the spring range was by stages. One brood 
that was watched closely made trips of approximately 1 mile, three- 
fourths mile, and 1^ miles in 6 days from June 2 through June 8. 
After the first major movement, this family remained for 3 days in an 
area less than 500 yards in diameter ; their droppings in piles formed a 
triangle with sides of 5, 15, and 17 yards, respectively. The move- 
ment of a combined brood of 3 hens and 16 to 25 young are recorded 
in figure 2, p. 23. 
Leopold (1933: 291) reports that- 
All observers unanimously and independently report a strong tendency for the 
grown young of most species of grouse to seek the vicinity of drinking water 
in late summer and fall, but whether they do this out of choice or necessity 
is not known. 

The early summer movement of young and adult Attwater's 
prairie chickens also was to the vicinity of surface water, but it 
was to water near which there also was shade. Pastures having an 
abundance of surface water but little or no shade-producing cover 
had few if any birds after mid-June. Likewise, places in which 
dense stands of weeds, shrubs, or tall grass were abundant, but sur- 
face WEiter scarce, were sparsely populated. More than 95 percent of 
the more than 500 Attwater's prairie chickens observed from June 
24 through September 4, 1937, were in heavy cover within a mile, 
generally within less than half a mile of surface water. 

The beginning of the summer movement is synchronous with the 
drying up of the wild indigo {Baptisia^ pi. 7), a plant that fur- 
nishes the principal shade on burns and heavily grazed areas from 
April through May. Prairie chickens require abundant shade in sum- 



North American Fauna 57. Fish and Wildlife Service 



PLATE 7 





B5068S: B49718A 



Above, Wild indigo (Baptisia) in a closely grazed pasture; Austin County, Tex., 
approximately 8 miles southeast of Sealy, April 10, 1938. Below, Shocked 
grain and waste in rice fields sometimes attract prairie chickens; Colorado 
County, Tex., 3 miles northeast of Eagle Lake, September 5, 1936. (Photos 
by V. W. Lehmann.) 



ATTWATER'S PRAIRIE CHICKEN 



23 



mer, for birds that were herded from such cover at midday panted 
vigorously, drooped their wings, and showed other signs of discomfort. 
They evidently rarely drink from surface water. In 1937, birds 
near water were closely observed, but only one was seen to drink 
during the entire summer. That was in Colorado County on June 
1, 1937, when a chick about 3 weeks old drank a few times from a 
puddle formed by water from a leaking windmill. The soft mud 
bordering ponds in inhabited prairie chicken range in Brazoria, 
Colorado, and Austin Counties was examined thoroughly at various 
times, but tracks of this species were never found. Grasshoppers 




FiGxmE 2. — Movements of a combined brood, May 1 to July 26, 1937, Colorado 
Comity. Birds seen in areas as follows : 1, May 1 to 28 ; 2, June 10 to July 
10; 3, July 15 to 26. 

and other favorite foods were frequently more abundant in summer 
in heavy cover near water, but the food factor was not thought to 
be of great importance at the time. The summer movements of 
prairie chickens to heavy cover near water are not satisfactorily ex- 
plainable on the basis of cover, water, and food, but these habitat 
conditions must be provided where stable populations are desired. 
After they found a satisfactory summer range, the prairie chickens 
moved little until fall, unless their summer territory was depleted 
or that nearby was more suitable. The population of a 460-acre 
pasture in Colorado County remained at nearly the same level (25 



24 NORTH AMERICAN FAUNA 5 7, FISH AND WILDLIFE SERVICE 

to 36 birds) from July 26 through September 3, 1937. The birds 
that rested in this area at noon each day, however, foraged and 
roosted largely in adjoining pastures, but their range was never more 
than 114 miles and usually under half a mile. 

Rains in 1937 sufficiently heavy to collect in low spots caused tem- 
porary spreading of prairie chickens from previously occupied areas. 
As the temporary water disappeared, however, the birds again con- 
centrated. 

Faix and Winter 

Populations that had been rather stable in certain pastures in Colo- 
rado County during the summer months of 1937 began shifting early 
in fall. About 25 birds that were summer residents of the M. Shin- 
dler cotton field from July through August were absent after Sep- 
tember 4. Two thousand acres of regularly censused pasture where 
prairie chickens were common in summer contained only 9 birds when 
rope counted on October 22. While the birds decreased generally 
in the large pastures, they increased around small farms near Sealy, 
Austin County ; Lissie, Wharton County ; and Bernardo and Chester- 
ville, Colorado County — ^territory 5 to 10 miles removed from the 
pastures in which birds had been most common during the preceding 
spring and summer. 

Distances traveled daily were evidently great in some instances. A 
bird killed by a farmer at 8 a. m. on September 1, 1936, was known 
to have traveled at least 3 miles since dawn, because its crop was 
filled with rice and the nearest rice field was that distant. Two in- 
dividuals, observed for 2 hours on the afternoon of October 22, 1937, 
traveled approximately 1% miles southeast of the point where first 
seen. When finally flushed, they flew an additional 2 miles or so in 
the same direction. A flock of four birds observed from 4 p. m. to 
6:15 p. m. on January 4, 1938, traveled more than 1% miles. The 
movement was in a circular direction, however, for at nightfall, the 
birds were less than half a mile from the point where they were first 
observed. Cool weather, fall rains, and a seasonal abundance of 
food and cover, especially in the vicinity of farming commrmities, 
probably were important in promoting the general fall scattering 
and the long daily trips the prairie chickens made in territory that 
was sparsely populated at other seasons. The birds reconcentrated 
in large pastures, however, as fall passed into winter. 

The population of the Everett pasture (640 acres), Colorado 
County, increased from November 3, 1937, through January 28, 1938 ; 
five censuses during that period showing 46, 58, 56 to 58, 73, and 84 
birds, respectively. Excellent food and cover conditions prevailed, 
for the area was lightly grazed. This increase in the number of 
birds apparently resulted from influxes from adjoining areas. After 



ATTWATER'S PRAIRIE CHICKEN 25 

November 15, few fluctuations in numbers between different pastures 
were reported by fence riders and others. Pastures that contained 
the greatest numbers in November and December 1937 also harbored 
the largest breeding populations the following spring. 

The data at hand show that late in fall, probably by about Novem- 
ber 15, the prairie chickens move to pastures where food and cover 
conditions are adequate. Having found such an area, they remain 
until spring. Probably the best way to attract a good breeding 
population, therefore, is to provide suitable food and cover conditions 
during the preceding winter. 

FOOD 

Data on the food of Attwater's prairie chicken were derived mainly 
from analyses of 21 stomachs (crops, or gizzards, or both) and more 
than 200 droppings (scats). Additional information was obtained 
by watching feeding birds at close range through field glasses. Of 
the 21 stomachs, 18 were of adult prairie chickens, 2 of chicks ap- 
proximately 10 days old, and 1 of a juvenile about 7 weeks old. 
Specimens were obtained as follows: 6 in winter (January and 
February), 6 in spring (April and May), 5 in summer (June through 
August), and 5 in fall (September through November). J. H. Gaut 
collected 3 stomachs near East Bernard, Wharton County, in May 
1905. Over the period beginning September 1936 and ending Au- 
gust 1938, 2 stomachs were obtained in Austin County, 4 in Eefugio 
County, and 12 in Colorado County. As the crops and gizzards 
of all birds found killed by automobiles, predators, poachers, and 
from other causes were saved, it was necessary to collect only 11 
specimens to balance the series according to seasons. 

Except during the breeding season, adult prairie chickens regu- 
larly feed twice daily, early in the morning (dawn to about 8 a. m.), 
and late in the afternoon (4 p. m. to dark) . Occasional bits of food 
are picked up throughout the day, but the gullets of specimens col- 
lected about noon are usually empty or nearly so. The food capacity 
of prairie chickens is large. Gullets frequently contain about 20 
cubic centimeters, and the gizzard about 30 cubic centimeters, of 
material. Since the birds ordinarily feed slowly and deliberately, 
apparently selecting their food with great care, it is not surprising 
that their diet in favorable areas is varied. Stomachs have been 
examined that contained 29 kinds of food and more than 1,300 items ; 
stomachs rarely contain less than 13 kinds of food of 500 items. 
Mature birds evidently feed mostly on vegetation at all seasons, 
for the stomachs of 18 adults (table 6, p. 26) contained 88.28 percent 
of plant material and 11.72 percent of insects. Animal matter prob- 
ably ranks higher than plants in the diet of young birds, however, 



26 NORTH AMERICAN FAUNA 57, FISH AND WILDLIFE SERVICE 

for the stomachs of 2 chicks and a juvenile (table 7, below) contained 
88.5 percent of insects. The ratio of plant to animal food varies 
according to season (table 8, below), insects, for instance, apparently 
being eaten in greatest quantity in summer. 

Table 6. — Composition of the stomach ^ contents of 18 adult prairie chickens 



Item 


Stomachs 

in which 

found 


Quantity 
present 


Item 


Stomachs 

in which 

found 


Quantity 
present 




Number 

18 

12 

16 

5 

6 


Percent 

88. S8 

27. n 

55.67 

1.30 

4.20 


Animal matter - 


Number 
18 

17 
8 
1 
1 

11 


Percent 

11.711 


Leaves and stems 

Seeds and pods 

Buds and flowers 

Miscellaneous * 


Insects: 

Adults 


10.83 


Eggs and larvae. - 

Round worms 

Prairie chicken feathers... 
Grit 


0.89 
W 
(') 
(») 







' Crops or gizzards, or both. 

» Woody pod septa, root stocks, and the like. 

s Trace. 

Table 7. — Composition of the stomach contents of three younff prairie chickens 



Item 


Stomachs 

in which 

found 


Quantity 
present 


Item 


Stomachs 

in which 

found 


Quantity 
present 


Vegetable matter 


Number 
2 
2 
1 


Percent 
11.5 
1.5 
10.0 


Animal matter 


Nuviber 
3 

3 
2 


Percent 

88.6 


Seeds or pods ... 


Insects: 

Adults 


86.0 




Eggs or larvae 


2.5 



Table 8. — Percentage of plant and animal food according to season 



Item 


Spring 


Summer 


FaU 


Winter 


Whole year 


Plants - 


94.25 
5.75 


71.0 
29.0 


85.8 
14.2 


95.0 
6.0 


86.51 




13.49 








Total . . 


100. 00 


100.0 


100.0 


100.0 


100.00 







The data at hand indicate that Attwater's prairie chickens are 
preponderantly granivorous, for seeds and seed pods made up slightly 
more than 50 percent of all the material in the stomachs of 18 adults. 
Much succulent vegetation is eaten, however, including leaves, buds, 
flowers, and root stocks. The birds also consume insect eggs, larvae, 
and adults, as shown in tables 6 and 7. 

Parts of some 50 kinds of plants and more than 65 species of 
insects were identified in the food from stomachs or scats, or by 
observations in the field. The names of these plants and insects 
together with the seasons when they are known to be eaten, are 
listed in tables 9 and 10, pp. 27 and 28. 



ATTWATER'S PRAIRIE CHICKEN 
Table 9. — Plant foods (56) of Attioatefs praiiHe chicken 



27 



Plant 



Marsileaceao: Pepperwort (MarsUea)... 

Poaceae: 

Paspalum (Paspatum citiatifotium type) _ . 

Bull grass {Paspaium boscianum ?) 

Paspalum {Paspaium plicatulum) 

Panic grass (Panicum scribnerianum) 

Panic grass (Panicum spp.) 

Crabgrass (Digitaria) 

Sandbur (Cenchrus) 

Hegari (Sorghum vulgare) 

Rice (Oryza sativa) 

Corn (Zea mags) 

Cyperaceae: 

Beakrush (Rynchospora) 

Sedge (Carex) 

Commeliuaceae: Dayflower (Commelina cris- 
pa). 

Alliaceae: Wild onion (Nothoscordum bivalve) . _ _ 

Liliaceae: (Undetermined) 

Leucojaceae: Stargrass (Hypoxis) 

Convallariaceae: Solomons seal (Polygonatum 
commutatum) . 

Ixiaceae: Blue-eyed-grass (Sisyrinchium va- 
rians). 

Polygonaceae: Dock (Rumex near crispus type), 

Ranunculaceae: Buttercup (Ranunculus near 
hispidus). 

Rosaceae: Dewberry (Rubus).. 

Malaceae: Chokeberry (Pyrus) 

Mimosaceae: 

Sensitive briar (Neptunia lutea).- 

Mimosa (Mimosa) 

Acacia (Acacia) 

Cassiaceae: Partridge-pea (Chamaecrista fas- 
ciculata) . 

Fabaceae: 

Wild pea (undet.) 

Wild pea (Lathyrus pusillus) 

Peanuts (Arachis hypogaea) 

Oxalidacoae: Woodsorrel (Oxalis)-. 

Euphorbiaceae: 

Doveweed (Crofon capitatus). 

Doveweed (C. glandulosus) 

Doveweed (C. monanthogynui) 

Spurge (Euphorbia) 

Spurge (Crotonopsis linearis) 

Spurge (Chamaesyce) 

Vitaceae: Grape (Vitis) 

Malvaceae: Mallow (Malva). 

Epilobiaceae: Oaura (Oaura) 

Ammiaceae (Cynosciadium) 

Convolvulaceae: 

Bindweed (Convolvulus) _ 

Evolvulus - - -- 

Polemoniaceae: Phlox (Phlox drummondi) 

Boraginaceae: Gromwell (Lithospermum) 

Verbenaceae: 

Fog fruit (Phyla nodiflora) 

Verbena (Verbena) 

Aeanthaceae: Ruellia (Ruellia ciliosa var. 
humilis). 

Rubiaceae: 

Buttonweed (Diodia teres) 

Buttonweed (Diodia virginiana) 

Bedstraw (Galium) 

Ambrosiaceae: 

Marsh-elder (Iva ciliata) 

Perennial ragweed (Ambrosia psilostachy a). 

Carduaceae: 

Thistle (Carduus) 

Tickweed (Coreopsis) 

Cichoriaceae: (Serinea oppositifolia) 



Parts eaten 



Leaves. 



Leaves, seeds. 

Seeds. 

..._do 

do. 

do 



.do. 
.do. 
.do. 
.do. 
.do. 



do 

Seeds, leaves.. 
Leaves, seeds. 



Leaves, flowers. 

Seeds 

Leaves, seeds... 
Seeds 



Seeds, pods. 



Seeds , 

Leaves, seeds, pods. 



Seeds, fruits 

Flowers, fruits. 



Leaves, flowers, seeds. 

Leaves, seeds 

Seeds 

Seeds, flowers 



Flowers 

Leaves... 

Fruits... 

Leaves, seeds. 



Seeds 

do 

Seeds, leaves. 

Seeds 

do 



do 

Seeds, fruits. 
Seeds, pods.. 

Pods.. 

Leaves. 



Seeds 

Seeds, pods 

Seeds, pods, flowers. 
Seeds 



Leaves, flowers, fruit... 
Leaves.- 

Leaves, stems, seeds 
buds, pods, flowers. 



Seeds 

do_ 

Leaves, seeds. 



do. 

Seeds. . 



do 

Flowers 

Seeds, pods. 



Seasons when 
eaten i 



Wi 

Sp, su, au, wi 

Au 

Sp, su, au 

Sp. 

Sp 

Au 

Wi 

Su, au 

Au, wi 

Sp... 

Su, au, wi 

Au 

Au.... 

Wi_ 

Su, wi.. 

Sp- 

Su... 

Sp, su 

Wi... 

Wi,sp-. 

Sp-.. 

Sp 

Au, wi, sp 

Su, au, wi 

Wi 

Su, au.. 

Sp-. 

Wi.. 

Au 

Wi, sp, su 

Au, wi 

Au, wi 

Au 

Au, wi, sp 

Au 

Au 

Su 

Sp 

Sp 

Wi 

Sp 

Sp 

Sp, su 

Su 

Sp, wi, au 

Wi... 

Au, wi.. 

Su, au, wi 

Su 

Sp, su, au 

Wi.. 

Au, vri 

Sp. 

Sp 

Sp, su 



Source of 
data' 



St. 

St, sc. 

St. 

St. 

St. 

St. 

St. 

St. 

Si. 

Si, St. 

St. 

St. 
St. 
St. 

St. 
St. 

St, si. 
St. 

St. 

St. 
St. 

St. 
St, si. 

St, si. 
St, sc. 
St. 
St, si. 



St. 
St. 
Si. 
St, sc, si. 

St, sc, si. 

St. 

St, si. 

St, sc. 

St. 

St. 

St. 

St. 

St. 

St. 

St. 

St. 
St, sc. 

St. 

St, si, 

St. 

St, sc, si. 



St, se. 
St. 
St, sc. 

St, si. 
St, sc. 

St. 
Si. 
St, sc. 



1 Abbreviations of seasons: Sp, spring; Su, summer; Au, autumn; and Wi, winter. 

2 Abbreviations of sources: St, stomach examination; Sc, scat examination; and Si, sight record. 

303807' 



28 NORTH AMERICAN FAUNA 5 7, FISH AND WILDLIFE SERVICE 
Tasle 10. — Some insect foods (68) of Attwater's prairie chicken 



Name 



Araneida: 

Spider (Lycosidae)__- 

Spider (undetermined) 

Orthoptera; 

Grasshopper (Cyrtaeanthacrinae) 

Pigmy locust (Aerydinae) 

Grasshopper (Syrbula) 

Grasshopper (Oedipodinae) --. 

Western grasshopper (Melanoplus ciner- 

eus). 
Green grasshopper (Chortophaga viridi- 
fasciata) . 

Grasshopper (Oedipodinae) 

Grasshopper (Schistocerca americana) 

Grasshopper (SaUatoria) 

Meadow grasshopper (Conocephalus) 

Long-horned grasshopper (Tettigoniidae) . 

Hemiptera: 

Shield bug (Pentatomidae) 

Bug (undetermined Hemiptera) 

Stinkbug (Euschisfus) 

Homoptera: 

Leafhopper (Cicadellidae)--. — 

Lantern fly (Fulgoridae). — . 

Soft scale (Leucanium) 

Coleoptera: 

Weevil {Graphorhinus vadosus), -.. 

Weevil {Lixus) 

Weevil (Thecesternus humeralis)-. 

Billbug (Sphenophorus minimus) 

Billbug {Sphenophorus bartramiae) 

Billbug {Sphenophorus germari) 

Billbug {Sphenophorus) 

Weevil {Boris) 

Weevil {Hyperodes) 

Rice-water weevil {Lissorhoptrus simplex). 

Weevil {Pachyphanes) 

Weevil {Anthonomus fulvus) 

Snout beetle (Curculionidae) 

. Weevil {Apion) 

Scarred snout beetle ( Tanymecus lacaena) _ 
Scarred snout beetle {Eudiagogus pulcher) 
Scarred snout beetle {Compsus auricepha- 



Leaf beetle {Phaedon viridis)... 

Leaf beetle {Cryptocephalus venustui) 

Leaf beetle ( Cryptocephalus) 

Leaf beetle {Zygogramma disrupta) 

Leaf beetle (Oedionychis petaurista) 

Leaf beetle {Metacroma ustum) 

Leaf beetle {Disonycha) 

Leaf beetle (Chrysomelidae) 

Leaf beetle {Calligrapha similis) 

Leaf beetle {Graphops pubescens) 

12-spotted cucumber beetle {Diabrotica 
duodecimpunciaia) . 

May beetle {PhyUophaga) 

May beetle (Scarabaeidae) 

Leaf chafer {Anomala ludoviciana) 

Dung beetle {Aphodius sp.) 

Ground beetle (Triplecfrus) 

Ground beetle {Eumolops) 

Ground beetle (Carabidae) 

Ground beetle (Chlaenius) 

Darkling beetle (Tenebrionldae) 

Lepidoptera: 

Moths, butterflies, and skippers (3 spe- 
cies) . 
Salt-marsh caterpillar {Estigmene acraea).. 

Diptera: 

Gall gnat (Cecidomyiidae) 

Robber fly {Asilus) - 

Hymenoptera: 

Gall fly (Gynipidae) 

Chalcid fly (Ghalcidae)... 

Paper wasp (Polistes) .- 

Ant {Odontomachus haemotodes) 

Ant {Pheidole sp) 

Fire ant {Solenopsis sp.) .- 



Form eaten 



Adult.. 
do- 



do 

Adult, larva. 
do 



_do- 
-do. 



-do- 



do 

do 

do 



do 

Adult, larva, egg. 



Adult Sp. 

Adult, eggs Sp- 

Adult Su. 



.do- 
.do.. 
.do- 



.do. 
-do- 
.do. 



-do- 
.do- 
.do. 
.do. 
.do. 
.do- 



_do_ 
.do. 
-do. 



-do. 
.do. 
.do. 
.do. 
.do. 



.do. 
.do. 
.do. 



.do. 
.do. 
.do. 



.do- 
.do- 
.do. 
-do. 
.do. 



.do.... 

.do 

.do.--. 

-do 

-do 

-do 

-do 

-do--.. 
-do 



Adult, larva, 
---do 



Larva. 
Adult. 



Adult, eggs 

Adult.-.. 

Adult, pupa eases. 

Adult 

....do 

....do... 



Seasons when 
eaten i 



Au 

Su, au- 



Sp, su 

Sp, su, au- 
Au 

Au 

Su, au 



Su. 



Su 

Su 

Su 

Sp, su, au. 
Su, au 



Wi, sp. 
Su, wi- 

Wi 

Sp----. 
Sp, au- 
Sp, au- 
Su, wi- 
Sp, su.. 
Sp.-... 

Sp 

Sp-.-.. 
Sp....- 
Sp, su.. 

Wi 

Wi 

Au 

Sp..... 



Wi 

Su, au 

Su 

Su, au 

Au 

Au 

Sp, su, wi. 
Sp, su, au. 

Wi 

Wi 

Wi 



Sp..- 
Su, au. 
Au 



Au, wi 

Wi 

Sp, su, au. 

Su 

Au 



Su, au. 
Su, au. 



Sp. 
Au. 



Sp..... 

Su 

Su, wi. 

Wi 

Su 

Su 



> See footnote 1, table 9. 
' See footnote 2, table 9. 



Au, wi, sp St. 

Sp, su, wi. St. 

Au St, sc. 



ATTWATER'S PRAIRIE CHICKEN 29 

Native plants are the most important source of food for the 
prairie chicken. Rated according to frequency of occurrence in 
stomachs and scats, gross bulk, and periods of availability, ruellia 
{Ruellia) appears to be by far the most important single food. It 
occurred in 13 of the 18 stomachs and made up almost 27 percent 
of all the material eaten. Stargrass {Hypoxis) , bedstraw {Galium)^ 
doveweed ( 6^rc>z^cn) , perennial ragweed {Ambrosia psilo'Stachya) also 
were eaten freely through long seasons. Practically all the impor- 
tant food plants utilized by the prairie chicken grow naturally in 
pastures that are moderately grazed. Corn was the only cultivated 
grain found, and the small quantity present was probably waste. 
It is known, however, that prairie chickens are fond of certain crops, 
especially peanuts, hegari, and ripened rice. The birds frequently 
congregate in peanut patches, particularly after the harvest, and 
scratch for the waste pods. They also use conveniently situated 
hegari fields extensively in summer, but the good shade in such 
areas is probably as attractive as the grain. Prairie chickens also 
range into rice fields after the crop is cut and shocked, and they 
sometimes feed on the grain in the shock as well as on that so freely 
wasted on the ground (pi. 7). The rice taken from shocks usually 
is not objectionable, although L. D. Roberts, Eagle Lake, Tex., 
reports that he saw approximately 1,500 of the birds feeding in a 
single field of about 500 acres in the Egypt section, Wharton County, 
in September 1920. By scratching, the prairie chickens loosen the 
shocks, thus allowing moisture to seep in, and this causes some com- 
plaint. A large increase of prairie chickens might conceivably bring 
on control problems in certain areas. The difficulties would prob- 
ably not be serious, however, because the birds could easily be 
frightened by shotgun fire or by other disturbances, and they quickly 
desert areas of potential danger. 

Among insect foods of Attwater's prairie chicken, 11 grasshoppers 
(6 identified to genus or species) are especially prominent; 32 
beetles (identified to genus or species, including 16 weevils) also 
are important. The vast majority (50 of 65) of the insects eaten 
by prairie chickens are kinds neutral (25) or harmful (25) to 
agriculture. Field observations, and reports of cooperators, show 
that prairie chickens eat in large quantities the moths of the cotton 
leaf worm {Alabcmm argillacea), one of the worst insect pests in 
the coastal area. Under ordinary conditions, the food habits of 
Attwater's prairie chicken, considering both insect and plant con- 
sumption, are such as to make it one of the most valuable birds of 
farm and range. 



30 NORTH AMERICAN FAUNA 5 7, FISH AND WILDLIFE SERVICE 

HABITAT REQUIREMENTS 
KIND OF HABITAT BEST SUITED 

The coastal prairie grassland is the real home of Attwater's 
prairie chicken, particularly in areas characterized by diversity of 
vegetation (pi. 8). Woodland, brushland, and cultivated land each 
furnish some food and cover at certain times and under certain 
conditions, but use of these types is optional with the prairie chicken, 
not vital. These secondary habitats are frequented mostly when food 
and cover are at the annual peak, as in September and October, 
but are little used at times of seasonal scarcity, as in December, 
January, February, and early in March. Wooded, cultivated, and 
brushy areas, individually or in combination, contribute little or 
nothing as courtship grounds and nesting cover. Properly managed 
grassland (pi. 9), however, satisfies every known requirement of 
Attwater's prairie chicken, and management, therefore, should be 
directed toward improvement of these areas. 

CHARACTER AND DENSITY OF VEGETATION 

Optimum food and cover conditions seemingly are approached 
when the prairie vegetation is varied in species, interspersion, and 
density. The plant life of well-populated areas includes a variety 
of grasses, sedges, rushes, and legumes, and tall weeds or their cover 
equivalent in the form of scattered clumps of myrtle or live-oak 
brush. The combination and density of the plants in the most 
favored places invariably is such as to provide cover in all degrees 
and well distributed. 

Light cover serves (1) exclusively for the courtship performance, 
(2) for feeding at all seasons, and (3) for a resort when dew is 
heavy or after rains. Light to medium heavy cover is used (1) for 
roosting, especially on gentle slopes, (2) by chicks under 5 weeks old, 
and (3) for feeding by adults throughout the year. Cover of a 
medium heavy to heavy character (pi. 9) is utilized (1) extensively 
for nesting, (2) as a loafing cover except during the hot summer 
months, and (3) as feeding grounds and escape cover in emergencies. 
Heavy cover (pi. 9) is essential (1) for shade in summer, (2) for 
protection against unfavorable weather and predators at other sea- 
sons, and (3) as a source of food, especially in fall. 

TOPOGRAPHY 

Kichness and variety in the vegetation are promoted by even slight 
variations in topography and soil (pi. 8). Consequently, the best 
natural range for Attwater's prairie chicken comprises country in 
which knolls, ridges, or hog wallows, are frequent. Further, knolls 



North American Fauna 57. Fish and Wildlife Service 



Plate 





ik.w$^ ^^ 



,yi, 






B49728; B50016 



Above, Diversified cover — excellent prairie chicken range; Colorado County, 
Tex., approximatelj' 7 miles northeast of Eagle Lake, September 4, 1936. 
Below, Diversity of topography and vegetation; Austin County, Tex., approxi- 
mately 6 miles northeast of Bellville, June 13, 1936. (Photos by V. W. Leh- 
mann.) 



North American Fauna 57. Fish and Wildlife Service 



Plate 9 





Above, Medium-heavy to heavy cover — excellent food-cover conditious in a 
moderately grazed pasture; Colorado County, Tex., approximately 8 miles 
north of Eagle Lake, December 21, 1936. Below, Heavy cover, mostly myrtle 
brush, near stream- — excellent summer range; Austin County, Tex., approxi- 
mately 4 miles east of Bellville, July 14, 1936. (Photos by V. W. Lehmann.) 



ATTWATER'S PRAIRIE CHICKEN 31 

and ridges are least likely to be inundated in times of flood and they 
afford the birds better opportunity of eluding their natural enemies 
and man. 

WATER 

The balanced prairie chicken habitat should offer a generous supply 
of surface water throughout the year. Although Attwater's prairie 
chickens may not be dependent on free water for survival during 
normal years (see p. 23), it has been established that their favorite 
summer range is rather well watered. During unusually dry years 
such as occurred in Refugio County in 1917, surface water may be 
an absolute necessity. Also, through its effects on vegetation and 
insect life, water is necessary for the maintenance of optimum cover 
and food conditions. The water supply of prairie chicken areas 
apparently is about optimum when permanent sources are available 
throughout the range at intervals not greater than a mile. 

Briefly, then, habitat conditions for Attwater's prairie chickens 
seemingly approach the ideal in grassland area when (1) the vegeta- 
tion is diversified and native grasses, sedges, legumes, and small and 
large weeds, or their equivalent in the form of brush or dwarfed trees, 
are present in such stands as to provide all densities of cover; (2) 
knolls, ridges, and hog wallows are frequent and the soils vary from 
loose sand to tight clay or silt; and (3) permanent sources of surface 
water are available not more than a mile apart. 

SEASONS OF SCARCITY 

In evaluating the suitability of an area for Attwater's prairie chick- 
ens it is to be kept in mind that its productivity or carrying capacity 
is not determined by conditions during the best season in a good year. 
Rather, as Taylor (1934) states, conditions that prevail during the 
most critical season of the year and in the most extreme year in a 
series of years determine carrying capacity. In the coastal country of 
Texas the season of scarity, or the period when food and cover are at 
a minimum, normally is from December through early March. The 
most critical years are those of heavy rainfall in May. 

LIMITING FACTORS 

Factors that have contributed to the decrease of prairie chickens 
in Texas may he classed roughly as (1) natural, including unfavor- 
able weather, predators, and disease; and (2) artificial, including 
cultivation, heavy grazing, burning, and overshooting. It might 
be more accurate to class limiting factors as those brought about by 
man, directly or indirectly. Although it is not generally appre- 
ciated, the decrease of prairie chickens in coastal Texas corresponds 



32 NORTH AMERICAN FAUNA 5 7, FISH AND WILDLIFE SERVICE 

with the spread of civilization. Prior to the coming of white men, 
the number of birds probably was well maintained, but there was 
a decrease as the country was developed. Attwater's prairie chicken 
will become extinct unless man ceases to exploit the soil, water, and 
other natural resources of its range. 

NATURAL FACTORS 

Rainfall Duiung the Nesting Season 

Prairie chickens in Texas evidently suffer greatly at times from 
extremes of weather. Heavy precipitation during the nesting and 
brooding season (March through June) appears to be an especially 
serious hazard, as indicated by the studies of Waddell and others in 
Colorado, Austin, and Wharton Counties. From 1925 through 1937 
Waddell estimated the size of the annual crop of young prairie 
chickens on the basis of the number of birds, both young and old 
(1) observed on almost daily trips through their range, (2) seen by 
reliable resident observers, (3) bagged by hunters, and (4) counted an- 
nually on the courtship grounds in spring. From his studies he con- 
cluded that crops of young prairie chickens were (1) good in spring 
months when rainfall was below average, (2) fair to good when 
rainfall was average or only slightly above average, and (3) poor, 
very few young being reared, when the nesting season was abnormally 
wet. 

Waddell's impressions as to the correlation between the amount of 
precipitation in spring and the size of the amiual crop of chickens 
were tested rather thoroughly in 1936 and again in 1937. In August 
1936, after a reconnaissance made with car and dog (see p. 52) over 
approximately 25,000 acres of territory in Colorado and Austin 
Counties, it was estimated that the annual increase was less than 10 
percent. Rainfall there was below average in March, April, and 
June 1936, but it exceeded 10 inches, or approximately twice the aver- 
age, in May, as shown by the records of the Weather Bureau at 
Columbus, situated centrally in that area. In 1937, when records 
of this station showed that rainfall was 2 inches or more below 
average in April, May, and June, rope counts made of 3,450 acres 
both before and after the breeding season revealed a 95-percent in- 
crease, supporting Waddell's estimate that the increase was good 
in a dry season. 

In table 11, p. 33, Waddell's estimates of the favorableness of the 
years from 1925 through 1937 for prairie chicken reproduction are 
presented together with precipitation records of the Columbus 
Weather Bureau Station for March, April, May, and June in those 
years. 



ATTWATER'S PRAIRIE CHICKEN 



33 



Table) 11. — Reproductive yield of AtHvater's prairie chicken in relation to spring 
rainfall in inches * in the Colorado County area ^ 





Estimated 
yield 


March 


April 


May 


June 


Year 


Precip- 
itation 


Depart- 
ure 
from 

normal 


Precip- 
itation 


Depart- 
ure 
from 

normal 


Precip- 
itation 


Depart- 
ure 
from 

normal 


Precip- 
itation 


Depart- 
ure 
from 

normal 


1925 

1926 


Good 

Fair... 


0.33 
11.54 
3.49 
1.42 
4.54 
2.34 
3.84 
3.63 
2.36 
3.91 
3.72 
1.23 
6.01 


-2.50 

-8.71 

.66 

-1.41 

1.71 

-.49 

1.01 

.80 

-.47 

1.08 

.89 

-1.60 

3.15 


0.99 
7.86 
4.00 
3.76 
2.58 

.48 
1.43 
2.19 
1.43 
4.28 
4.58 
3.48 

.52 


-2.74 
4.13 

.27 

.03 

-1.15 

-3.25 

-2.30 

-1.54 

-2.30 

.55 

.85 

-.25 

-3.21 


2.87 
4.10 

1.24 
2.00 

16.12 
3.11 
1.98 
.66 
3.67 
1.90 
9.21 

10.65 
.47 


-1.51 

-.28 

-3.14 

-2.38 

11.74 

1.27 

-2.40 

-3.72 

-.71 

-2.48 

4.83 

6.27 

-3.91 


1.06 
3.37 

6.43 

8.52 

.99 

.89 

.90 

3.68 

1.40 

.22 

2.48 

.79 

1.37 


-2.12 
.19 


1927 

1928 

1929 


Good... 

do 

Poor 

Fair 

Good 

do 

Fair 


3.25 

5.34 

-2.19 


1930 

1931 


-2.29 
-2.28 


1932 

1933 


.50 
-1.78 


1934 


Good 

Poor. 

do 

Good 


-2.96 


1935 

1936 

1937 - . 


-.70 
-2.39 
-1.81 







I Records of U. S. Weather Bureau Station, Columbus, Colorado County. 

' Colorado County, north central Wharton County, southwestern Austin County. 

Waddell found good crops of young birds in the Eagle Lake area 
in 1925, 1927, 1928, 1931, 1932, 1934, and 1937, years when rainfall 
in May was 1.5 inches or more below average. Fair crops of young 
prairie chickens were thought to have been reared in 1926, 1930, 
and 1933, when rainfall in May was approximately average (0.28 
below in 1926) to only slightly above (1.27 above in 1930). Poor 
crops were matured in 1929, 1935, and 1936, when May precipitation 
was appreciably above (approximately twice) the average for that 
month. Unusually heavy or light precipitation in March, April, or 
June evidently had little influence on the broods of young, for good 
crops were recorded in 1927, when rainfall was decidedly above 
average in June, and a poor crop is known to have occurred in 1936, 
when rainfall was below average in all months of the nesting season 
except May. The records at hand suggest, therefore, that the rain- 
fall in May is a fairly satisfactory index of the suitability of the 
year for the reproduction of Attwater's prairie chicken under natural 
conditions. Good crops usually result when the rainfall in May is 
1.5 inches or so below average; fair crops are probable when it is 
approximately average or only slightly above ; and poor crops appear 
almost a certainty when the rainfall for that month is decidedly 
above average. 

Rainfall in May is of greater significance than that in any other 
month, as the 1937 and 1938 nesting studies showed that most of the 
chicks hatch in May. Those hatched in April do not yet have a 
serviceable covering of feathers by May and, consequently, are almost 
as vulnerable to the rains as are birds hatched in that month. Nests 
flooded in March and April may be rebuilt, for the booming season 
is still in full swing, but nests flooded after May 1 are seldom re- 



34 NORTH AMERICAN FAUNA 57, FISH AND WILDLIFE SERVICE 

established because the mating season is then nearly over. May, then, 
is the climax, or peak month, of the breeding season, and rainfall 
then is of greater significance than at any other period. 

The nature of rains in May may be a factor modifying the use of 
precipitation records for that month as indices of the number of 
chicks produced, as short, heavy downpours may be more serious than 
slow steady rains. This, however, is not known to be true. Fre- 
quently recurring light rains may be as serious as heavy ones be- 
cause persistent damp conditions result in heavy juvenile mortality 
from chilling. Stoddard (1931: 39, 202) shows that wet spring 
months are favorable for hatching but not for rearing bobwhites. 
Percolation and drainage are slow in the heavy coastal prairie soil, 
and surface moisture accumulates from persistent light rains as surely 
as from brief heavy ones ; the amount rather than the severity of the 
rain seems to rule. 

While it is realized that annual precipitation, drainage, cover, and 
other environmental conditions in Colorado County are not identical 
with those obtaining throughout the coastal prairie chicken country, 
a marked similarity does, nevertheless, exist. Rainfall is moderately 
heavy, 39 inches annually, at Columbus, Colorado County, and it is 
also generous throughout the bird's range. Average annual precipi- 
tation varies from 49.35 inches at Beaumont, Jefferson County, to 
33.69 inches at Austwell, Refugio County, at about the eastern and 
western limits, respectively, of the subspecies. Rainfall during May 
at Columbus (average, 4.38 inches) is heavier than in any other 
month. May is the wettest month in Jackson, Goliad, Lavaca, and 
Harris Counties as well. Heavy or persistent rains transform tre- 
mendous areas in Colorado County into veritable lakes ranging from 
a few inches to several feet in depth; rains produce similar results 
throughout the coastal region. It appears justifiable, therefore, to 
assume that rainfall in May is the key to prairie chicken reproduc- 
tion throughout coastal Texas (fig. 3). 

Of every 5 years in a given locality, apparently 2 are favorable 
for nesting, 2 fair to poor, and 1 bad, as determined by rainfall in 
May. Conditions are never uniform in the chicken country a^ a 
whole because there is variation between counties and even between 
parts of the same county. Records of the Weather Bureau for May 
1935 show, for example, that rainfall at Galveston, Galveston County, 
was favorable (2.71 inches below average) ; at Houston, Harris 
County, fair (only 0.20 inch below) ; and that at Columbus, Colorado 
County, poor, being approximately twice average (4.83 inches above). 
During 1926 in Brazoria County conditions were good at Alvin, fair 
at Angleton and Freeport, and poor at Brazoria. In 1932 conditions 
were good at Angleton, fair at Freeport, and poor at Alvin. Though 
man cannot regulate rainfall to promote prairie chicken welfare 



North American Fauna 57, FUh and Wildlife Service 




LEGEND 

Rainfall 1.50 inches or more below average f^— ) (Good) 

Rainfall 1.49 below average to 1 .99 above average fTTT] (Fair) 

Rainfall 2 inches or more above average, but less than twice average MlIlX (Poor) 

Rainfall twice average or more ^^B (Bad) 

Compilations based on records of average annual May rainfall at each individual station as 

supplied by the Climatological Division. U. S. Weather Bureau. 
Records missing or unsatisfactory ^ | O ) 



Rainfall conditions in May in the range of Attwater's prairie chicken in Texas, in the 66 years 1871 to 1936. 
indicating the probable frequency of good and other reproductive years for the birds 



ATTWATER'S PRAIRIE CHICKEN 35 

at nesting and brooding time, in many caseg he can regulate pasture 
burning and grazing to provide adequate nesting cover in the best- 
drained parts of the land. Also, he can consult weather records 
before setting open seasons and bag limits, which should not be 
uniformly applied but adjusted to local conditions to preserve the 
birds. 

Floods 

Flood conditions are often produced by heavy rains in the over- 
grazed and overf armed sections in the upper part of the State. 
Heavily burdened streams carrying flood crests from the upper coun- 
try sometimes spill over their low banks and spread their silt-laden 
waters over thousands of acres of prairie chicken range. This oc- 
curred in the Rock Island-Garwood section (Colorado County) in 
June 1936, when the prairie chicken population of that section was 
extirpated. Floods evidently are a constant menace to birds near 
major streams. 

Dbought 

Extreme drought seriously affects prairie chickens, especially dur- 
ing the hot summer months. G. P. Ferguson, State game warden, 
and fence riders on the M. O'Conner ranch, Refugio County, found 
many dead birds in the especially dry summer of 1917 and saw others 
too weak to fly. Drought reduces food supplies for both present and 
future use. Large cracks that form in black soil in dry weather pos- 
sibly trap some young birds, according to the observations of Gross 
(Bent 1932: 253). Birds weakened by excessive heat, and possibly 
also by a shortage of food, are especially vulnerable to disease, pred- 
ators, adverse weather, and other hazards. 

HUBBICANES 

Tropical hurricanes sometimes produce flood conditions in prairie 
chicken country 20 miles or more from the Gulf. In 1917 a storm 
backed salt water over the greater part of the Pipkin ranch in the 
Big Hill area in Jefferson County and drowned livestock by the 
hundreds. That it evidently destroyed many prairie chickens as 
well was indicated by their exceeding scarcity for 15 years afterwards. 

Hatt. 

Heavy hail storms destroy many Attwater's prairie chickens, es- 
pecially in areas where heavy protective cover is lacking. After a 
storm in May 1934, J. O. Linney, Guy Ferguson, and fence riders on 
the Salt Creek ranch, Refugio County, saw about 150 dead or crippled 
chickens. 



36 NORTH AMERICAN FAUNA 5 7, FISH AND WILDLIFE SERVICE 

Local Stobms 

Local storms, especially those that commonly occur in fall, kill 
turkeys and other domestic fowls and prairie chickens and other game 
birds, as reported by Marcus Shindler, Ed Koy, and other resident 
land-owners in the northeastern part of Colorado County. 

Disease 

Gross (1930a: 39), and Stoddard, Curtis, Lews, Terrel, and others 
(Leopold 1931: 182-183), recorded incidents strongly suggesting that 
disease and parasites probably were important controlling factors on 
the abundance of the greater prairie chicken of the Northern States. 
Records at hand do not show that, in the past, disease has been a factor 
of importance limiting the numbers of Attwater's prairie chicken in 
Texas. The observations, mentioned above, made by G. P. Ferguson 
on the M. O'Conner ranch furnished the only known evidence even 
faintly suggesting an outbreak of disease. In that instance, however, 
it is probable that mortality, if really due to disease or parasites, was 
an indirect result of prolonged drought. No evidence of disease or 
heavy parasitism was found in autopsies made on 13 prairie chickens, 
and no evidence of any unhealthful condition was observed among 
hundreds of birds in the field. Prairie chickens are doubtless sus- 
ceptible, however, to ailments of domestic poultry. An outbreak of 
blackhead disease, probably contracted from domestic turkeys, is con- 
sidered by Gross (Bent 1932: 268) as a major factor in the extermina- 
tion of the heath-hen. Turkeys and other poultry, therefore, probably 
are unhealthful influences on a prairie chicken range. 

Speead of V^oody Vegetation 

The encroachment of mesquite, live oak, various acacias, and other 
kinds of brush onto open prairie land has been an extremely impor- 
tant factor in reducing the range and doubtless the numbers of Att- 
water's prairie chickens in Refugio and other counties to the south 
and west. Within the memory of living men extensive prairies have 
been transformed into brush jungles. Specific factors that have in- 
fluenced the rapid vegetational changes in the southwestern brush 
country are imperfectly understood. Factors probably of importance 
in enabling woody plants to replace the native grassland flora have 
been overgrazing, especially during drought j^ears; the mechanical 
planting of tree seeds by cattle and horses, because livestock eat large 
quantities of mesquite and other beans, the seeds of which pass through 
the digestive tract and are distributed or planted by the droppings; 
the elimination of burning, previously mentioned by Bray (1901: 
288-290) and Tharp (1926: 71) ; and the lowering of the water table. 
Be that as it may, hundreds of thousands of acres of what was once 



ATTWATERS PRAIRIE CHICKEN 



37 



tall-grass prairie are now brushlaiid, and prairie chickens are gone 
from these areas. 

Pkedation 



Natural enemies consume some of the eggs, young, and adults of 
Attwater's prairie chicken. The extent of predation on nests and the 
identity of other factors responsible for nest loss in the Eagle Lake 
area are eiven in tables 12 and 13. 



Table 12. — Fate of nests, Eagle Lake, Colorado, 1937 



Nest 
No. 


Pasture 


Date 
found 


Date 
destroyed 

or 
hatched 


Probable cause of destruction 


1 


Everett 


Apr. 7 

Apr. 8 
Apr. 12 
__..do.... 
Apr. 13 
Apr. 21 
____do..__ 
_...do.-_. 
Apr. 27 
Apr. 29 
May 1 

May 11 
June 1 


Apr. 22 

Apr. 4 3 
Apr. 7 
Apr. 13 
May 17 
Apr. 15 
Apr. 21 
Apr. 18 
May 4 
May 15 
May 2 

Apr. 6 
June 2 

or 
June 3 




21 

3 1 


do 

Wintermann_ 


by a farmer. 
Red wolf— female bird killed on nest. 


4.. 

5 


do 

Sklar-M arcella 

Wiutermann 


Skunk. 

Hatched successfully. 


61 


Skunk. 


7 1 

81 

9 


do 

do 

Duncan 


Do. 
Deserted, cause unknown. 
Hatched successfully. 


10 


Everett . 


Do. 


11 


Willis 


Man — nest deserted after farmer plowed territory 

nearby and revisited nest frequently. 
Opossum. 


12 2 

13 


Sklar-Marcella 

... do 









1 Nest destroyed when found. 

' Estimated in case of nests destroyed when found. 

> Indicated by circumstantial evidence at the nest. 

Table 13. — Fate of nests. Eagle Lake, Colorado County, Tex. (1938) 



Nest No. 


Pasture 


Date 
found 


Date de- 
stroyed 

or 
hatched 

May 3 
Apr. 23 
Apr. 29 
May 3 
May 11 
June 21 


Probable cause of 
destruction i 


14 


Sen 


Apr. 13 
Apr. 18 
.. do .. 


Heavy rain. 


15 


Thomas . . 


House cat. 


16 


do 


Hatched successfully. 


17 


... do 


Apr. 29 
Apr. 20 
June 3 


Heavy rain. 


18 


Everett 


Opossum. 


19 


. do 


Hatched successfully. 









I Indicated by circumstantial evidence at nest. 

Of 19 prairie chicken nests studied in 1937 and 1938, 6 (31.5 
percent) were successful, and 13 (68.4 percent) were lost. In 1937 
8 of 13 nests studied were destroyed before the clutches were com- 
plete, showing that the laying period may be the one of heaviest 
nest loss. This might be expected, as the eggs are covered only about 
an hour or so each day during that time. This loss is somewhat 
compensated, however, by renesting (see p. 15). Opossums and 
skunks destroyed 6 nests — more than any other agency. Of the 6, 



38 NORTH AMERICAN FAUNA 5 7, FISH AND WILDLIFE SERVICE 

however, 4 were in a pasture where unregulated fire had restricted 
good nesting cover to 2 small unburned areas about 3 and 10 acres 
in size. Fur animals as well as nesting chickens were unnaturally 
concentrated in these unburned plots; dens containing young were 
100 yards or less from each of the nests destroyed. Excessive pas- 
ture burning appeared to be the primary cause of the heavy nest 
loss ; predation by fur animals being merely an effect, the agency of 
destruction that was inevitable after the burning. 

Field evidence showed that a red wolf killed a female prairie 
chicken and destroyed her nest; a feral house cat devoured the 
eggs from another nest (pi. 10). It is surprising that dogs did 
not figure as predators on the nests and that house cats did not 
take an even greater number. Wandering dogs, usually in groups of 
three to five, were not imcommon on Colorado County prairies; L. 
A. Burchfield, a trapper who worked for the former Bureau of 
Biological Survey in Colorado County in 1937, and Waddell found 
that dogs did much of the damage for which the few red wolves, 
now largely extirpated in the area, were blamed. Heavy predation 
on a flock of domestic turkeys, supposedly by wolves, stopped imme- 
diately when a hound, which frequently hunted on its own initiative, 
was killed after having been caught in a trap set for the alleged 
wolves. Feral house cats on Colorado County prairies probably 
outnumber skunks, opossums, minks, or any other fur animals. Cot- 
ton rats and other rodents were common near several nests but took 
no eggs. Neither did racers, chicken snakes, king snakes, or other 
reptiles frequently noted after May 1 in both 1937 and 1938. 

Three nests were abandoned, desertion of two of these, possibly 
all three, being caused by man. Nesting* prairie chickens seem 
especially sensitive to interference, and they should not be dis- 
turbed by persons making repeated visits. Of six nests under obser- 
vation in 1938, floods destroyed two, and accumulated water from 
heavy rains came within ly^ feet of a third (nest 16). The following 
excerpt from the writer's field notes of May 3, 1938, emphasizes the 
importance of floods : 

The prairie has been transformed into a miniature ocean clotted by tiny 
islands that previously had been the tops of knolls and ridges. On these 
islands sit wet and bedraggled prairie chickens and other birds that seem as 
confused and astounded as I by the sudden change in their environment. About 
a 5-inch depth of vrater covers the sites of nests 14 and 17, and former 
nest 15. Nest 16 has escaped by a hair's breadth, but the lining is very soggy. 
Problems due to hawks, skunks, and other predators seem so petty v^^hen exces- 
sive rain destroys virtually everything at a single stroke. 

YOUNG 

Although predators doubtless exert great pressure on the popula- 
tion of young prairie chickens in some areas, especially because the 



North American Fauna 57, Fish and Wildlife Service 



Plate 10 











ICV 



■■"4ili 





Above, Shells of eggs at prairie chiclcen nest destroyed by house cat; Colorado 
County, Tex., approximately 5 miles north of Eagle Lake, April 23, 1938. 
(Photo by Texas Game, Fish, and Oyster Commission; E. P. Haddon.) Below, 
Freshly killed prairie chicken recovered from a ferruginous rough-legged hawk; 
Colorado County, Tex., approximately 6 miles north of Eagle Lake, April 7, 
1937. (Photo by V. W. Lehmann.) 



North American Fauna 57, Fish and Wildlife Service 



PLATE 1 1 





B49777A; E60058 

Above, Xative bluestem prairie— well populated b.y prairie chickens: Colorado 
County, Tex., 6 miles northeast of Eagle Lake, December 21, 1936. Below, 
Prairie after plowing for rice — deserted by prairie chickens; Colorado County, 
Tex., ajjproximately 5 miles north of Eagle Lake, March 7, 1938. (Photos 
by V. W. Lehmann.) 



ATTWATER'S PRAIRIE CHICKEN 39 

loose formation of the brood (see p. 19) and straying apparently 
induce mortality from this cause, definite information was difficult 
to obtain. 

A female Krider's hawk caught a third-grown prairie chicken on 
May 24, 1937. From then on until June 9, when the male was col- 
lected, this hawk, assisted by her mate, hunted a section containing 
six broods. Most migrant raptors (roughlegs, redtails, and marsh 
and duck hawks) had left Colorado County prior to May 1, 1937, and 
April 15, 1938, before many young had hatched, and the resident 
species (red-shouldered. Cooper's, Sennett's white-tailed, and Krider's 
hawks) confined their activities largely to wooded areas. Because 
cover is dense in summer, and hawks are then uncommon, probably 
few young prairie chickens are taken in normal years. 

House cats with freshly killed young prairie chickens were noted 
twice in 1937 and were seen stalking broods on three other occasions. 
Because of their numbers and predilections, house cats are thought 
to be exceedingly destructive. 

ADULTS 

Prairie chickens on the courtship grounds seemed more intent 
on mating than on self-preservation ; consequently, losses from preda- 
tion were probably heaviest at mating time. In Colorado County, 
during most of the 1937 and 1938 courtship seasons the abundant 
hawks harassed the prairie chickens persistently, sometimes with 
success. On April 8, 1937, 3 duck hawks, 7 marsh hawks, 2 rough- 
legs, 3 Krider's hawks, and 2 bald eagles kept the chicken population 
(about 45 birds) of the Everett pasture (640 acres) constantly mov- 
ing. A freshly killed male prairie chicken (pi. 10) was taken from 
a ferruginous roughleg in that area on April 17. Marsh hawks, 
which Stoddard and others have found to be sometimes more bene- 
ficial than harmful to quail and other game, were especially an- 
noying to courting birds, no other factor interfering with their 
activities to so great an extent. Wlien a marsh hawk darted at 
one occupant of the booming ground, others generally cowered. The 
hawks pursued their intended victims for short distances, but soon 
returned and flushed others, or after dispersing the grouse, fre- 
quently alighted on the courtship grounds to await their return and 
resume the flushing tactics. On April 8, 1937, 4 marsh hawks con- 
centrated on a single courtship ground and harassed the 6 male 
occupants from 5 to 7 :30 p. m. Although no birds were killed, one 
lost many feathers when two hawks dived at it simultaneously. 

By flushing prairie chickens, marsh hawks render them vulnerable 
to more efficient winged enemies, as duck hawks, goshawks, and the 
like. Waddell has seen duck hawks catch adult chickens on at 
least two occasions. 



40 NORTH AMERICAN FAUNA 5 7, FISH AND WILDLIFE SERVICE 

Mammals also take some of the birds on courtship areas. The 
stomach of a male house cat collected April 12, 1937, near a booming 
ground in the Everett pasture, Colorado County, contained the head, 
feet, and part of the breast of a freshly killed male prairie chicken. 
The remainder was found about 50 feet away. 

A red wolf was suspected of killing a female prairie chicken on 
the nest, and either red wolves or dogs took three others in Colorado 
County in April 1937. 

Only six instances of adult mortality were discovered that year, 
although intensive search for remains was made on foot and in cars 
over approximately 2,500 acres. In 1938, when none of the pastures 
were burned, no dead birds were found. 

Review of Natueai. Factors 

Natural factors limit the abundance of prairie chickens by destroying 
eggs, young, and adults and by reducing favorable territory. During 
the breeding season floods, storms, hail, drought, and excessive or per- 
sistent rains are known to be locally serious, the rains in May being most 
damaging. Drought has been associated with the only reported out- 
break of disease that occurred in the Refugio area in 1917. The en- 
croachment of brush on prairie land has transformed thousands of acres 
of what was once good prairie chicken range (pi. 11) into an unfavorable 
habitat. Although some predators harass the birds throughout the 
year, their effects are probably most serious at mating and nesting 
time. Natural mortality from climate and predators is severe in 
inferior or isolated cover. 

The serious effects of natural factors are in every case either brought 
about or intensified by man's generally unwise treatment of natural 
factors. All except feral house cats and predatory dogs were operat- 
ing against the prairie chickens, apparently without disastrous results, 
before the environment was radically modified by man. Since the 
unfavorable influences of natural agencies are due chiefly to man, it 
is encouraging to know that it is within his power and often decidedly 
advantageous to him so to modify his actions as to improve existing 
conditions and promote the welfare of the prairie chickens as well as 
his own. 

ARTIFICIAL FACTORS 

Agrictjlttiee 

Much of the best prairie chicken range has been recently appro- 
priated for agricultural uses. More than 2,000,000 acres (table 14) 
were cultivated in 1936. In addition, thousands of acres of sod are 
plowed annually, with the extension of agriculture, especially rice 
farming. The acreage yearly planted to rice in coastal Texas in- 



ATTWATER'S PRAIRIE CHICKEN 



41 



creased from approximately 174,500 acres in 1922 to more than 196,500 
acres in 1937.^ This latter acreage represents only a small part of the 
area actually depleted: rice farming has ruined more than 84,000 
acres for the birds in Colorado County (pi. 11) alone, and probably 
in excess of a million acres in the State as a whole. Rice is hard on 
the land and most areas devoted to it can be profitably cultivated 
during only about 1 year in 4, after which they must be left fallow for 
about 3 years to "sweeten." Weedy rice fields ostensibly provide satis- 
factory grouse range ; actually, however, they lack suitable courtship 
grounds and safe nesting cover, and, furthermore, the levees collect 
water that floods nests. Prairie chickens in fallow rice land ap- 
parently are doomed even though they are hunted lightly or not at 
all. According to Waddell, there were 10,000 of the birds on 30,000 
acres of the Egypt section, Wharton Comity, in 1924. Rice farming 
began there in 1925, and by 1937 all the 30,000 acres were either in 
cultivation or fallow. Hunting pressure was reduced annually after 
1925, and few, if any, birds were killed after 1935. In 1938, however, 
less than 150 prairie chickens remained. Prairie chicken decrease was 
also positively correlated with the expansion of rice farming in eastern 
Chambers and central Matagorda Counties. As additional acres of 
prairie are plowed, further decreases are certain to follow. 



Table 14. — Harvested and other crop land (1936) in counties partially or en- 
tirely within the probable former range of Attwater's prairie chicken in 
Texas ^ 



County 


Harvested 
crop land 


Other 
crop land 


Total 
crop land 


County 


Harvested 
crop land 


other 
crop land 


Total 
crop land 


Aransas 


Acres 

2,484 
105, 396 

92, 247 
98,045 
34, 425 

130, 684 
16, 772 

93, 562 
153, 307 
176, 495 

19, 848 
64, 374 
100, 263 
82, 609 
44,205 


Acres 
1,772 
11,313 
20, 685 
17, 787 
12, 580 
32, 483 
5,727 
11,038 
30, 843 
41, 793 
3,396 
12, 711 
25, 031 
15, 114 
12, 386 


Acres 

4, 256 
116, 709 
112, 932 
115, 832 
47, 005 
163, 167 
22, 499 
104, 600 
184, 150 
218, 288 
23,244 
77, 085 
125, 294 
97,723 
56, 591 


Kenedy . 


Acres 

204 

28, 639 

158, 604 

47,704 

59, 714 
228, 609 

8,245 
40, 147 
165, 691 
100, 300 
47, 986 
187, 555 

60, 981 


Acres 


Acres 
204 






7,211 
10, 652 
12, 836 

21, 952 
62, 090 

1,334 
16, 183 
35, 769 
17,828 
10, 040 

22, 909 
10, 001 


35 850 


Bee 


Lavaca 


169 256 


Brazoria 


Liberty 


60 540 




Matagorda. - 

Nueces 


81 666 


Cameron - - 


290, 699 
9 579 


Chambers 


Orange 




Refugio 


56, 330 
201 460 


DeWitt - - 


San Patricio 

Victoria 


Fort Bend 


118, ] 28 


Galveston 




58, 026 


Goliad - 


Wharton 

Willacy 


210, 464 
70, 982 






Total 






2,349,095 


483,464 


2, 832, 559 





1 Data from Texas Almanac and State Industrial Guide, pp. 231-236, The Dallas News, 1936. 

Pasture Burning 

Unregulated prairie fires intentionally set or of accidental origin 
have been, and still are, common in coastal Texas in every month of 



•^ Figures supplied by David Wintermann, Relow Land Company, Eagle Lake, Tex., from 
data compiled by the Rice Milling Association. 



42 NORTH AMERICAN FAUNA 57, FISH AND WILDLIFE SERVICE 

the year. In Colorado and Austin Counties, for example, approxi- 
mately 80 percent of the best prairie chicken country was burned over 
in 1936. A fire of accidental inception ran over about 3,000 acres of 
the 6,700 acre J. C. Anderson Estate ranch, Harris County, in May 
1937. The cover on about 3,000 acres of the best prairie chicken 
country in Matagorda County was intentionally burned in July 1937. 
Pasture burning is an annual event on the Pipkin ranch, Jefferson 
County, fires being started during first new moon after February 15. 
Areas that the first fires do not cover cleanly are subsequently treated, 
and burning generally continues well through the nesting season. 
Most ranchmen, however, complete pasture burning by March. 

The pastures are burned to remove old grass and encourage tender 
new growth more palatable to livestock. Fires usually are set when 
the grass is dry and the wind brisk, in order to finish the job quickly. 
The resulting fast, hot fires entirely denude areas except in low spots 
and deplete pastures of food, escape cover, and nesting sites. Prairie 
chickens and their natural enemies are crowded into unburned areas 
(pi. 12) and predation is undoubtedly intensified. During the breed- 
ing season fires destroy nests and probably many young birds as well ; 
no fewer than nine nests with charred eggs were found by Waddell in 
a 640-acre pasture burned in May 1936. Plant life recovers slowly 
in the absence of abundant rain; consequently, fires accentuate the 
results of drought. Altogether, fire is one of the most important 
factors limiting prairie chicken numbers in pastures. When burning 
is carried on as outlined under Management (pp. 53 to 54), however, 
the evils are greatly reduced or entirely eliminated, and benefits 
accrue to forage and soil as well. 

OVEKQRAZINO 

With the possible exception of Orange and Jefferson Counties, over- 
grazing is severe in most of coastal Texas from late in fall through 
early spring. In addition to reducing cover and food for prairie 
chickens (pi. 12), overgrazing probably also increases the vulnera- 
bility of the birds both to natural enemies and to man. In Colorado 
County from 1936 through 1938, for example, it was noted that marsh 
hawks and other raptors harried chickens more persistently in lightly 
vegetated pastures than in areas where heavy grassy cover was pres- 
ent. Waddell observed that hunters regularly kill a higher percent- 
age of known populations in areas where cover is light than where it 
is heavy. In Colorado County it has been found that the winter 
prairie chicken population of a pasture can be forecast with consider- 
able accuracy by observing the extent to which the area is grazed. 
Large winter populations are rare in pastures where cover is short. 



North American Fauna 57. Fish and Wildlife Service 



PLATE 12 






B49778: B60059 



Above, Excellent unburned cover at right of road; inferior burned cover at left; 
Colorado County, Tex., approximately 7 miles north of Eagle Lake, December 
22, 1936. Below, Scanty cover where there has been overgrazing; the shrub is 
Cherokee rose (Rosa laevigata); Colorado County, Tex., 6 miles north of Eagle 
Lake, March 7, 1938. (Photos by V. W. Lehmann.) 



ATTWATER'S PRAIRIE CHICKEN 43 

Aside from resulting unfavorably to prairie chickens, overgrazing 
in the gulf coastal country has been and is resulting in (1) the spread 
of undesirable brush and weeds, (2) the increase of needlegrass and 
other largely unpalatable grasses, and (3) serious erosion. An abun- 
dance of prairie chickens cannot be maintained on overgrazed tracts ; 
it is equally impossible to maintain forage and soil on such areas. 

Orti Deveix)pment 

Oil development, which began with the discovery of the Spindle 
Top field in Jefferson County in 1901, has extended to every county 
in the coastal section. All the Attwater's prairie chicken area is 
classed as potential oil land, and almost every acre has been surveyed 
not once, but several times by oil crews. Veritable forests of oil der- 
ricks now stand in areas that once provided some of the finest prairie 
chicken range. In these areas, as in Fort Bend County, prairie 
chickens are almost, if not completely gone. 

Drainage 

Drainage canals, as in Brazoria and certain other coastal counties, 
have in some instances improved the territoiy within a mile or so of 
their margins by providing a permanent water supply where it was 
otherwise lacking during the summer months. On the other hand, 
drainage canals have doubtless decreased the general wildlife pro- 
ductivity of the counties in which they are situated by speeding up 
the run-off and thus lowering the water table. Until recently many 
prairie ponds retained water throughout the year, produced crappie, 
bream, and other edible fish, held safe nesting cover for black 
mallards and other water birds, grew an abundant supply of food for 
wintering waterfowl, and served as concentration points for prairie 
chickens during the heat of summer. Now they go dry during the 
slightest drought and produce virtually nothing. 

Pastube Mowing 

Regular mowing of grassy areas, mainly for hay or increased 
forage production, has promoted a nearly pure stand of grass in some 
of the areas treated and has reduced shade and food, and the general 
attractiveness of the areas for prairie chickens and certain other 
valuable wildlife. In Colorado County, areas that have been mowed 
regularly for long periods are virtually game deserts ; prairie chickens 
use them little even at nesting time. Pasture mowing in coastal 
Texas appears to be extending rapidly, and further reduction in 
wildlife resources may be expected from this cause unless definite 

303807°— 41 4 



44 NORTH AMERICAN FAUNA 57, FISH AND WILDLIFE SERVICE 

modifications are effected. Fortunately, the detrimental effects of 
pasture mowing to upland game birds may be mitigated, at least to 
some extent, by following management recommendations listed on 
page 56. 

Mechanical Accidents 

Prairie chickens sometimes fly into telephone wires, fences, and 
houses, or are struck by automobiles. In six instances in 1937 birds 
were noted as accidentally killed in the Eagle Lake section — as many 
as were recorded for predation. Mortality from accidents may be 
far more serious than is generally appreciated. 

Hunting 

Last, but not least, hunters certainly have contributed to prairie 
chicken decrease. Hunting has never been well regulated, and laws 
governing the taking of the birds have always been inadequate. Ac- 
cording to the Texas Game, Fish, and Oyster Commission (Ann. 
Kept., 1929: 86-91) prairie chickens had no legal protection until 
1883, when a 5-month closed season was declared during the breeding 
period. In 1885, 148 counties claimed partial or total exemption to this 
and other regulations, and it was not until 1903 that the legislature 
passed a bill designating the months of November, December, and Jan- 
uary as the open season and setting a daily bag limit of 25. The legis- 
lation of 1903 was indeed a forward step, but there was no conserva- 
tion body to enforce the measure, local officers being depended on 
to carry out its provisions. The Game, Fish, and Oyster Commis- 
sion was not created mitil 1910, and for many years it was without 
adequate funds and personnel. As late as 1919 there were only 
6 salaried wardens in Texas endeavoring to carry out, as best they 
might, almost wholly inadequate regulations. The law restricting 
the open season on prairie chickens to 4 days, September 1 to Sep- 
tember 4, inclusive, and the bag limit to 10 a day or 10 a season, 
was not passed until 1929. In 1937 there were only 9 full-time 
wardens in all the Attwater's prairie chicken country, and they were 
charged with patrolling more than 8 million acres ! 

Development of the coastal territory, as farming, grazing, and 
the exploiting of oil, crowded prairie chickens into ever smaller 
areas, where they were more easily found and killed. The Hug- 
the-Coast Highway (State Highway No. 35) and various other roads 
increased patrol problems; the intercoastal canal in Galveston, Cham- 
bers, and Jefferson Counties made formerly remote areas easily 
accessible to poachers. The number of hunters increased as trans- 
portation facilities and weapons were improved. The open season in 
September, normally a dry period (see pp. 57 to 58), did much to 



ATTWATER'S PRAIRIE CHICKEN 46 

popularize hunting from automobiles. With these and other advan- 
tages, hmiters evidently harvested too closely. In the Bernard River 
country (western Austin County and northeastern Colorado County), 
for example, it is known that in 1936 hunters killed 66 chickens, or 
22 percent of the estimated total population (300). This was accom- 
plished despite the fact that the gunners were closely supervised and 
did not hunt in the most densely populated pastures. It is probable 
that excessive kills have occurred in other areas for many years; 
the 1937 census showed that Attwater's prairie chickens were nearly 
or completely extirpated except on or adjoining lands where they had 
been hunted little, if at all, for at least 10 years. In Harris, Galves- 
ton, Waller, and possibly in parts of other counties, hunting has 
probably been the agency most largely responsible for prairie chicken 
decline. 

MANAGEMENT 

Leopold (1931 : 3) has defined game management as the art of 
making land produce annual crops of wild game for recreational use. 
In coastal Texas, the management of prairie chickens must consist 
largely of the preservation of suitable grassland areas. Increased 
protection, habitat improvement, adequate predator control, and 
proper regulation of the harvest, however, will greatly encourage 
recovery. 

PROTECTION 

An act (H. B. 30) passed by the State legislature, effective Sep- 
tember 24, 1937, forbade the killing of prairie chickens in Texas for 
a period of 5 years. This measure removes much of the pressure 
previously exerted on the birds during the regular open hunting sea- 
son, for true sportsmen will observe the decree. Landowners, game 
wardens, and other interested individuals, however, will remember 
that close seasons may tend to stimulate rather than retard the opera- 
tions of game bootleggers. According to the consensus of State 
game wardens in the coastal territory, violators are especially active 
(1) during the birds' spring courtship season when the conspicuous 
males, their instincts of self preservation dulled by the the mating 
urge, are easy targets for .22-caliber rifles; (2) late in July and 
August, when the tame young birds are of "frying" size; and (3) 
during the duck season, when whirring flocks of Attwater's prairie 
chickens evidently tempt gunners who have insuificient self control. 
Coastal game wardens report that, in years past, probably as many 
prairie chickens were illegally killed during the duck season as were 
taken legally during the then open season in September. The restora- 
tion of the species demands close protection for the remaining birds 
at all times. 



46 NORTH AMERICAN fAUNA 5 7, FISH AND WILDLIFE SERVICE 

Altliough. game wardens in the prairie chicken country are sin- 
cere and energetic, the territory is too vast for adequate protection 
under the facilities available. Sportsmen may render valuable aid 
by helping conservation officers apprehend irresponsible hunters, but 
landowners or their resident agents must handle the job if prairie 
chickens are to receive anything like adequate protection. Land- 
owners, individually or in groups, would do well to incorporate their 
holdings to form game-management areas, as advocated by the Ex- 
tension Service, Texas Agricultural and Mechanical College and the 
Texas, Game, Fish, and Oyster Commission. Under that plan, in- 
creased protection is provided through appropriate posting and 
provision by the landowners of qualified, resident, free-service State 
game wardens. Also technical service is given in solving predator 
problems, improving wildlife food and cover, properly regulating 
harvests, and otherwise maintaining wildlife crops. Nonresident 
owners should check up on the manner in which their foremen 
or lessees protect wildlife during their absence. It is regrettably 
true that some supposedly protected ranches are in reality hunting 
clubs for irresponsible agents and their friends when the landowners 
are away. Long-time lessees who wish to manage prairie chickens or 
other game should insist that their contract include control over the 
wildlife resources of the property as well as over grazing or other 
values. These lessees may thus avoid embarrassment from unwel- 
come hunter guests directed to the area by the absentee owners. 

Landowners who contemplate leasing their holdings for oil develop- 
ment might well follow the precedent set by a ranch owner in Refugio 
County. Each of his contracts carries the provision that the lease 
shall terminate immediately after any representative of the contract- 
ing company is caught on the property with a gun of any kind. 
Such a clause properly shifts the burden of supervising irresponsible 
oil workers from the landowner to the oil company. 

Increased protection of the few remaining Attwater's prairie 
chickens is necessary for success in management. Protection alone, 
however, is largely ineffective in areas where proper food and cover 
conditions are lacking. 

HABITAT IMPROVEMENT 

At present there are few areas in Texas where excellent conditions 
for prairie chickens prevail, and populations fluctuate markedly 
(table 15). Increase or decrease in study areas was thought fre- 
quently to coincide with fluctuations in the supplies of food, cover, 
or surface water. In many areas marked seasonal movements may 
be averted and larger and more stable populations maintained by 
removing deficiencies in habitat. 



ATTWATER'S PRAIRIE CHICKEN 



47 



Table 15. 



-Fluctuations in numhers of prairie chickens, Thomas and Koy pas- 
tures, Colorado County, 1937 





Size 


Prairie chickens found 


Pasture 


Feb. 
221 


Apr. 
13 


May 
2 


June 
2, 8, 10 


July 
26 


Sept. 
1 


Oct. 

22 


Nov. 

1 


Thomas 


Acres 
817 
460 


Num- 
ber 
31 



Num- 
ber 
30 



Num- 
ber 
28 



Num- 
ber 
37 16 
14 


Num- 
ber 

23 


Num- 
ber 
17 
32 


Num- 
ber 




Num- 
ber 
1 


Koy 










> Count of birds at or near the courtship grounds; no allowance made for any birds that may have been 
missed. All other counts were by the rope method. (See p. 49.) 

Evaluating Conditions 

In some instances it is relatively easy to point out one or more ways 
in which areas are inferior. Safe nesting cover is deficient in burned 
pastures that are devoid of old vegetation except in low damp places. 
Shade is insufficient on lands kept free of tall weeds or shrubs by 
mowing or grazing. Winter food, or cover, or both are usually lack- 
ing in areas having few native food-cover plants, as ragweed, 
goatweed (Croton), marsh-elder, or ruellia. Sometimes, however, 
habitat deficiencies are obscure and general observations of an infre- 
quent nature do not identify them. Accurate inventories are of 
assistance in determining (1) whether habitat improvement is needed, 
(2) what should be done, (3) results of work done, and (4) the sur- 
plus available for hunting. Management programs should be formu- 
lated on the basis of data obtained during inventories conducted 
thrice annually, in spring, summer, and winter. Inventory methods, 
recording and interpreting data, and management practices are dis- 
cussed in the following paragraphs. 

Census Methods 
spring count on the courtship gb0und8 

The first census method that has been tried and found useful is 
the spring count of birds on the courtship grounds. Necessary are 
an automobile, preferably of light build and high clearance, a driver 
who is well acquainted with the area, and someone to act as observer, 
note keeper, and gate opener. 

A count is made on each courtship ground in the area, recording 
the number and sex of birds assembled there and the number and 
sex of birds seen between these grounds. The number of hens is 
recorded as a supplementary check. The number of males, increased 
80 to 110 percent to allow for females that will be missed is accepted 
as the total population of the census area. For best results, the 



48 NORTH AMERICAN FAUNA 5 7, FISH AND WILDLIFE SERVICE 

spring count is made in March from daybreak to about 7 : 30 a. m. 
A population estimate based on the maximum count obtained by 
reworking the same area tliree successive mornings, or often enough 
to offset variations due to unfavorable weather, is likely to be suffi- 
ciently accurate. Where recounts are impracticable, the single enu- 
meration should be made on a clear, quiet morning after a brisk 
norther. 

Courtship grounds may be located by sight or sound of the birds 
assembled there, but it is preferable to "drive out" the census area in 
belts 150 yards or less wide. Drumming grounds should not be ap- 
proached more closely than is necessary, because flushing the birds 
leads to inaccurate counts. As birds frequently squat, or freeze, at 
the approach of a car, it is desirable to wait at each occupied booming 
ground and refrain from counting until after vigorous courtship ac- 
tivity has been resumed. It is good policy to encircle a counted area 
completely before proceeding to a new site, for the fresh car tracks 
often assist in avoiding duplication. 

The accuracy of spring counts on the courtship grounds was tested 
in the following ways: (1) A section (640 acres) was covered on 10 
successive mornings; (2) a 1,000-acre pasture was searched with the 
aid of 15 bird dogs; (3) a 1,000-acre pasture was recounted by 5 men 
using 2 cars, 3 horses, and 2 dogs; (4) a section worked 3 successive 
days was rope counted. Spring counts have been made over ap- 
proximately 150,000 acres in Colorado, Wharton, and Austin Counties. 
These studies show that the enumeration of birds on the courtship 
grounds is the most rapid and economical of all known census tech- 
niques. More than 2,000 acres a morning have often been covered in 
areas having populations of about 1 bird per 45 acres. There are no 
indications that the method affects courtship activities adversely or 
that it greatly endangers early nesting. Also, the spring count of 
males is useful in yielding data on prairie chicken abundance in com- 
parable areas worked at nearly the same time and under nearly the 
same conditions. 

The spring count of birds on the courtship grounds, however, is 
not without its defects. Its accuracy is influenced by weather and 
other conditions at a time convenient for counting. Opportunity is 
limited to a few hours a day (from about 6 to 7 : 30 a. m.) over a short 
period (in March). The spring count does not reveal the number of 
females present, consequently, it does not produce reliable quantita- 
tive data on sex ratio and total population. Some observers experi- 
ence difficulty in distinguishing males from females, especially in the 
poor light of early morning. To them the analysis of sex differences, 
presented on p. 49, may be helpful. 



North American Fauna 57, Fish and Wildlife Service 



PLATE 13 




r»-' '*»-"i»% * 









B49329; B48929 



Above, Rope counting of prairie chickens on Matagorda Island, Tex., October 30, 
1937. Below, Rope counting in myrtle brush; Liberty County, Tex., approxi- 
mately 8 miles southeast of Devers, June 27, 1937. (Photos by W. P. Taylor.) 



ATTWATER'S PRAIRIE CHICKEN 



49 



FIELD BASIS FOR DIFFERENTIATION OF THE SEXES IN SPRING 



Males 
General color Light gray 

Color of breast Not perceptibly different 

from that of back. 

Barring on back and Heavy, black, well defined- . 
breast. 

Color of head Orange - colored comblike 

structure present above 
each eye. 

Feathers of crest Seldom erect 

Neck Appears thick and heavy, 

with large, brightly col- 
ored (orange) air sac 
apparent on each side of 
neck under prominent 
(2.25 to 2.90 inches) neck 
tufts. 

Size Large, heavy (about 2}^ lb.). 

Action on courtship Bold, struts, fights, and 
grounds. booms in open cover. 

Flocking Usually in groups of 8 to 12 

when booming, feeding, 
or resting at midday. 

Flushing Laborious take-off; cackles 

when rising from ground. 



Females 

Brownish gray. 

Much lighter than that 
of back; appears al- 
most white in flight. 

Light, brownish black, 
poorly defined. 

Orange -colored combs 
absent. 

Frequently erect. 

Appears thin and long; 
air sac and neck tufts 
rudimentary {%a inch 
long). 



Small, light (about 1^ 

lb.). 
Shy, does not strut, fight, 

or boom. 
Usually alone. 



Easy take-off; usually 
does not cackle. 



THE ROPE COUNT 



A second method of counting, one that has been tested with most 
encouraging results in the coastal prairie chicken country, is the rope 
count (pi. 13). Essential equipment includes two automobiles, 
preferably of light build and high clearance, an inch rope or a 
quarter-inch flexible steel cable 60 to 120 yards in length, and two 
strong swivels. An extra supply of water for radiators is needed 
in hot weather as cars heat up under the heavy going. In addition 
to drivers for the two cars, a third person should be taken along, if 
possible, to act as note keeper and general handy man. 

When the census area is reached, one swivel is attached to the 
right end of the rear bumper of the car in which the note keeper 
is to ride, and the second swivel is attached to the left end of the 
rear bumper of the other machine. Each end of the rope or cable 
is then securely tied to a swivel. Care must be exercised to see that 
the rope or cable, in turning, will tighten its twist and not loosen or 
unravel. One machine takes position parallel to a fence or other 
definite landmark while the other goes far enough way to stretch the 
rope so that only a slight bend remains. After both cars are in 
position, they drive over parallel courses at a uniform speed of 5 



50 NORTH AMERICAN FAUNA 57, FISH AND WILDLIFE SERVICE 

to 15 miles an hour, which may be increased in light cover but 
which should be reduced in heavy vegetation to keep the rope, for 
the greater part of its length, about 5 inches above ground. Birds 
are tabulated as they are flushed. Those flying into uncovered ter- 
ritory are deducted when that area is dragged. Wlien the end of 
a strip is reached, the car in which the note keeper rides turns and 



ICAftl 



Belt 5. End Here - 



*-1 



L 



Belt4. 



Belt 3. 



Bsin. 



t 



Ei 1 1 



Rope^i ^art Ksr< -» ^'" '• 



FiGUEE 4. — ^Diagram of the rope count. Arrows show course of each car. 

retraces its course while the other car makes a wide swing to the 
outside margin of another belt (fig. 4). This is repeated until every 
part of the census area has been covered. 

The principle of rope counting is not new. Askins (1931: 8) re- 
ports that market hunters and others in Kansas "* * * hitched 
a wire between two wagons and with these driving across the prairie 
300 yards apart, the gunners walked behind the wire taking the 
grouse as they arose until the wagon was filled." Butchers of wild- 



ATTWATER'S PRAIRIE CHICKEN 51 

life (they have no claim to the title of sportsmen) have used modi- 
fications of this system in coastal Texas for years. 

The rope census method has been checked and rechecked for ac- 
curacy against the spring counts of birds on the drumming grounds, 
car counts, and counts with bird dogs. The rope count, by far the 
most efficient of all, has been tried over approximately 45,000 acres 
of grouse range, including every major prairie type in which Att- 
water's prairie chickens occur in Texas. Heavy myrtle brush, as 
in Jefferson, Liberty, and other counties east of the Brazos River, 
light to heavy Paspalum-Andropogon grassland as in Brazoria and 
Colorado Counties, live oak shinnery in the northern part of Vic- 
toria County, rough weedy hog wallow blackland of Refugio County, 
and even the extremely rough salt-grass area of the same section, 
have all been negotiated successfully. These tests have demonstrated 
clearly the practicability of the rope count under all coastal prairie 
conditions. Another advantage is speed; a party can easily cover 
2,000 acres a day ; Waddell and the writer having counted the birds 
on an area of this size in one morning. 

Ropes last for a considerable period, one that has been dragged 
over 20,000 acres still being used. This method of counting is not 
closely limited to a short season, or to a particular part of the day, 
as is the spring count on the courtship grounds. The accuracy of 
the rope count is not dependent on special weather conditions or on 
other variables over which man has no control, its major advantage 
lying in the fact that, when properly used, it gives an accurate 
quantitative count in the census area. For that reason, it is most 
useful in prairie chicken management. 

The rope count is dangerous for the layman to use during the 
nesting season and when young birds are small (during the latter 
part of March through June), for unless extreme care is taken, nests 
may be broken up and young birds injured, scattered, or even killed 
by a fast-moving, 1-inch rope. A i^-inch rope, 50 yards long, how- 
ever, has been used with success in locating nests and broods without 
detriment to the birds. Coffee-bean plants, yaupon bushes, trees, 
and old fence posts are obstacles to rope counting, but they can be 
avoided without great loss of time, and, with care, few breaks in 
the rope or cable result. Of course, cultivated fields cannot be 
traversed without injury to standing crops, and counting is difficult 
and sometimes impossible in fallow rice fields where levees are high. 
Inexperienced persons sometimes have trouble in keeping the proper 
amount of slack in the rope and in following the car tracks which 
are depended upon to mark the inside margin of every new belt. 
These minor difficulties, however, are rapidly overcome by practice. 



52 NORTH AMERICAN FAUNA 5 7, FISH AND WILDLIFE SERVICE 

CAR-DOG COUNT 

A car-dog count is made by driving out an area in belts 40 to 
150 yards wide and releasing dogs to work the area where birds are 
known or strongly suspected to be. Necessary equipment consists of 
one car and one well-trained dog, but two cars, with a man and two 
dogs in each, speed up the work more than 100 percent. 

Since 1936 this method has been employed in working over 25,000 
acres. It is economical and is highly enjoyable to dog lovers, but 
it is slow. The work of different dogs and that of the same dog at 
different times and under different conditions varies greatly. Dup- 
lications in counts or recounts are virtually unavoidable on well- 
populated range, and misses are frequent. As reliable data are diffi- 
cult to obtain by this method, it should be used only when other census 
techniques are impossible. 

Using the Census 

Censuses produce the most dependable information when applied 
over an entire management area. Where this is impracticable and 
sampling is resorted to, care must be taken to insure that the selected 
area is typical with respect to vegetation, topography, water, and the 
like, and is sufficiently large. In a pasture consisting of 60 percent 
flat grassland with little or no brush and 40 percent sandhills covered 
with live oak shinnery it would be incorrect to sample only the sand- 
hill territory and apply the findings to the flat grassland as well. 
Sampling should be divided proportionately between distinct environ- 
mental types. Sample areas should be at least a section, or 640 acres, 
in size, and they should preferably cover 2,000 acres. Thoroughness 
should never be sacrificed for extent of coverage, however, as accurate 
censuses made thrice annually on a well-chosen section over a period 
of several years will yield infinitely more usable data than will hap- 
hazard counts sporadically undertaken over more territory than can 
be conveniently handled. 

During the spring census, investigators should list (1) males, (2) 
females, (3) occupied courtship grounds and the number of males at 
each, (4) unoccupied courtship grounds, and (5) jack rabbits, in areas 
where they are a common resident species, as in the country west of the 
Brazos Kiver. Census sheets should show also (1) name of the pasture, 
(2) name of owner, (3) size of sample area, (4) exact location, (5) 
date of census, (6) counting method used, (7) weather, and (8) names 
of the investigators. Additional notes taken should describe (1) the 
type of country censused, whether flat grassland with few weeds, 
rolling country with scattered myrtle bushes, and so on ; (2) grazing 
pressure, whether light, medium, or heavy; and (3) recent burns on 
high or low ground, showing the percentage of area burned, whether 



ATTWATER'S PRAIRIE CHICKEN 53 

burn is general or spotty, and the location of unburned cover. Care- 
ful compilation of data greatly facilities accurate interpretation. 

If prairie chickens are numerous in the sample area, 1 to every 
10 acres or less, cover conditions should not be changed. Instead, 
steps should be taken to insure that grazing and burning practices 
will duplicate the conditions in future years. If the birds are scarce, 
less than 1 to every 10 acres, and if they have not been overshot, habitat 
deficiencies should be sought and corrected. 

SPRING 

Probable habitat deficiencies limiting prairie chicken numbers in 
spring are scanty, poorly distributed, or overdense nesting cover 
and a shortage of suitable courtship grounds. Common causes 
of deficient cover are general burning and overgrazing that result in 
scarcity or complete absence over more than 60 percent of the area 
of old vegetation, left from previous years at an average height of 
at least 5 inches, and poorly distributed cover confined to a particular 
part of a pasture or to low, poorly drained situations. Undergrazing 
is the usual cause of overdense cover, the thick matted vegetation that 
chickens regularly avoid. Where jack rabbits (Taylor, Vorhies, and 
Lister, 1936) are a common resident species, they are usually either 
very nmnerous, 1 to every 10 acres or less, or entirely absent where 
cover is too scanty or too poorly distributed to be suitable for nesting 
prairie chickens. Jack rabbits are frequently scarce, 1 to every 80 
acres or more, however, in cover that is overdense. A markedly un- 
balanced sex ratio, with more than twice as many male prairie 
chickens as hens, also has been noted in pastures where nesting cover 
was deficient. 

In areas in which the cover is scarce because of general burning, 
conditions are improved by leaving 40 percent or more of the grassy 
cover unburned each year. Unburned cover should be well distributed 
over the pasture, the greater part being on the highest, best-drained 
ground, in patches of 5 to 40 acres. Favorable conditions are en- 
couraged if burning is carried on when there is little or no wind and 
the vegetation is slightly damp. A quiet day following a light shower, 
or a still night after the dew has begun to fall, is preferable. A test 
fire should be set in a protected corner of the pasture. If it burns 
slowly, consuming only the most combustible material, and dies down 
in 6 to 15 minutes, a series of fires then may be set throughout the 
pasture. The number should be strictly regulated by the acreage to 
be burned and the manpower available to curb the fires in case of such 
unforeseen difficulties as a fresh breeze that may put fires out of con- 
trol. The best insurance against trouble from that cause is a plowed 
fire lane, 5 to 10 feet wide, completely encircling the pasture and 



54 NORTH AMERICAN FAUNA 5 7, FISH AND WILDLIFE SERVICE 

dividing it into blocks of approximately 100 acres each. All pasture 
burning should be completed by December or early in January, well 
in advance of the nesting season. 

Moderation in grazing is important. Cattle should not be left to 
graze on a tract until unpalatable bunch grasses, as smut grass, salt 
grass, big bluestem, and tlie like, are all that remain. Ideal condi- 
tions are approached when the number of animal units is strictly regu- 
lated according to the quantity and quality of the available forage. 
This practice avoids a condition of cover that is scanty in dry years 
and overdense in wet years, and, besides being favorable to prairie 
chickens, it conserves the soil and the range. 

A shortage of courtship grounds, short-grass areas from one-half to 
10 acres in extent surrounded by light to medium-heavy grassy cover, is 
frequently indicated by an unbalanced sex ratio with more than twice 
as many females as males or by a preponderant male population of 8 
to 15 or more birds on each booming ground. Common causes of in- 
adequate courtship facilities are (1) a lack of hardpan flats; (2) 
general burning, which denudes vegetation over a wide area and causes 
prairie chickens to leave ; and (3) undergrazing, resulting in tall cover 
even on hardpan areas. These deficiencies, however, are remedied by 
spot burning and moderate grazing. 

SUMMER 

Probable deficiencies that limit the number of birds in summer are 
an insufficient supply of water in dry years and inadequate shade. A 
count made from July 1 through August 10, preferably over the same 
area covered in spring, reveals the number of young produced, and 
thus serves as a check on the success or failure of the breeding season. 

The data recorded for the summer count should be the same as for 
the spring count and, also, investigators should note (1) the number 
of young, (2) the number, character, and location of water supplies, 
and (3) distribution of birds with respect to water and weedy cover. 

A larger population of adult prairie chickens than was found in 
spring shows either that the spring census was inaccurate, or that 
other birds have moved in. In the latter event no habitat manipula- 
tion should be attempted unless the resident population plus the in- 
flux averages less than 1 bird for every 10 acres, and a larger popula- 
tion is desired. If the adult population has decreased since spring, 
however, and it is established that poaching has not occurred, the 
census data should be examined for information suggesting causes 
of the decline. 

Indications of deficient water are the absence of watering places a 
mile or less apart, and the concentration of birds and jack rabbits in 
parts of the area where water is available. Indications of deficient 



ATTWATER'S PRAIRIE CHICKEN 55 

shade are the scarcity of prairie chickens and jack rabbits where sur- 
face water obtains. Ordinary causes of insufficient water are drainage 
and unusually dry seasons. Water supplies can be improved by clean- 
ing and deepening natural ponds or constructing new ones, and allow- 
ing windmill pumps to spill over and maintain puddles nearby. 

Common causes of inferior shade are heavy grazing and mowing. 
Shade deficiencies usually can be corrected naturally by moderate 
grazing and leaving unmowed plots 1 to 10 acres in extent in flats 
near ponds. Other methods of obtaining and maintaining tall shading 
cover are by (1) fencing tracts from % to 10 acres in size within 100 
yards of water holes and leaving the fenced areas ungrazed ; (2) plant- 
ing tamarisk, chinaberry, black locust, elm, sycamore, cottonwood, or 
other adapted trees near water supplies; (3) constructing two or more 
brush racks 5 by 6 by 2 feet high on knolls on high ground near 
ponds ; and (4) strip plowing near ponds as outlined on page 56. 

An increase of 100 percent in the number of prairie chickens in any 
year is excellent. An increase of 50 percent or less may indicate 
either a poor breeding season or abnormally high predation. Rainfall 
records for May show whether breeding conditions are poor; in the 
event heavy rainfall is not the causative agent, predators' may be 
responsible. In the latter instance, the number of predatory dogs 
and house cats should be reduced by shooting or trapping. If a thor- 
ough job is done and yet the increase is small, the aid of State or 
Federal wildlife technicians should be solicited. 

WINTEB 

In winter, a grouse habitat may be deficient in food, cover, or both. 
This may best be determined by study of information obtained during 
a December or early January reconnaissance of territory that was 
covered in summer. Except for the data on the number of young 
birds and on the water supply, information recorded in winter should 
be the same as that in summer, and it should show whether birds are 
generally distributed or heavily concentrated in small areas. The rope 
count is the preferred method of winter census, dog counts being made 
only when rope counting is impracticable. 

Assuming that poaching is not a factor, a winter population larger 
than that of the summer, shows habitat conditions on a census area 
already more favorable than those in pastures nearby and suggests that 
management be directed at maintenance, rather than at alteration of 
environment. A winter population smaller than that of the summer 
suggests food or cover deficiencies. Other indicators of such inad- 
equacies, generally occurring together in heavily grazed areas, are a 
prevalence of largely unpalatable plants, as goat weed, marsh-elder, 
dogfennel, perennial ragweed, smutgrass {SporobokiS poiretii), and 



56 NORTH AMERICAN FAUNA 5 7, FISH AND WILDLIFE SERVICE 

cordgrass; a concentration of prairie chickens in small parts of the 
area; and an abundance of jack rabbits (averaging 1 to every 10 acres 
or less) , or their complete absence. Indications that food only is lack- 
ing are a uniform growth of heavily matted grass, a sparse growth 
of weeds, and a scarcity of jack rabbits (averaging 1 to every 80 acres 
or more). Moderate grazing encourages favorable food and cover 
conditions. 

To make up for local shortcomings, prairie chicken managers may 
establish (1) stockproof -fenced areas of i/^ to 10 acres in as large num- 
bers as practicable; (2) plowed strips 20 to 50 feet wide dividing 
sparsely inhabited parts of pastures into blocks of 50 to 200 acres; and 
(3) unmowed patches of cover of 2 to 10 acres or more, situated not 
more than 300 yards apart. Fenced areas should not be grazed, and, 
if possible, half of each fenced area should be planted annually to 
Schrock, German millet, dwarf milo, hegari (pi, 14) , or red-top cane. 
Brush racks built in the corners of fenced areas attract quails as well 
as prairie chickens. In average years strip plowing may be done 
with satisfactory results from December through April, but February 
is considered most favorable. The best effects on experimental areas 
in Wliarton County and at College Station have been obtained on 
strips that were plowed shortly before or after a rain and harrowed 
immediately after the preliminary breaking. Unmowed patches of 
cover should be left on knolls or ridges, in flats around ponds, or in 
other places where sizable stands of weeds occur. 

General Recommenditions for Habitat Control 

Landowners who do not undertake intensive management of prairie 
chickens based on counts made three times a year may adopt any 
or all of the following general recommendations with the assurance 
that some improvement will result: 

Pastures should be grazed moderately by livestock. 

Pasture burning should be completed before February 1 ; in excess of 40 
percent of the pasture should be left unburned, with the remaining 
cover v/ell distributed in patches of 5 to 40 acres on the best drained 
areas. 

Mowing should not be done before July 1 ; unmowed patches of 2 to 5 
acres or more, not more than 300 yards apart should be left on flats, 
knolls, or in other places where there is a good stand of weeds. 

In summer windmill pumps should be allowed to form puddles. 

Predatory house cats and dogs should be rigidly controlled. 

The present 5-year close season (effective September 1937) should be 
enforced. If and when the season is reopened, not more than 35 percent 
of the known population should be shot when rainfall in May is normal 
or less. In years when rainfall in May is approximately twice normal, 
no birds should be kUled. 



North American Fauna 57. Fish and Wildlife Service 



Plate 14 




ATTWATER'S PRAIRIE CHICKEN 57 

PREDATOR CONTROL 

Exhaustive studies by McAtee (1931, 1932, 1935, 1936), McAtee and 
Stoddard (1930), Fisher (1893)), May (1935), and others have dem- 
onstrated rather conclusively that the food of most flesh-eating birds 
and manmials is determined mainly by the availability of prey. 
Errington (1935) adds that predation is largely confined to in- 
secure or surplus populations; in areas where there is adequate 
food and cover, hawks, owls, skunks, opossums, and the like feed 
principally on the more common rats, mice, snakes, frogs, and insects, 
rather than on the less numerous, swift, and elusive game birds. 
Flesh eaters often are neutral, and may be actually beneficial, in 
relation to sport and agriculture. Specific data presented on the 
relationships of Attwater's prairie chicken and its natural enemies 
(pp. 37 to 40) are by no means so comprehensive as desired. The 
information at hand, however, apparentl}'^ justifies the following 
general recommendations concerning predator control on prairie 
chicken range : 

Feral house cats and predatory dogs may well be controlled. 

Hawks, owls, and fur animals should not be killed Indiscriminately, their 
control being limited to known offenders. Inhumane pole traps should 
not be used. (All raptorial birds except Cooper's, sharp-shinned, and duck 
hawks, goshawks, and great horned owls are protected in Texas.) 

Fur animals should be taken only during open seasons when furs are prime, 
and the harvest should be regulated to promote sustained yields. 

HARVESTING THE SURPLUS 

Former laws governing the shooting of Attwater's prairie chickens 
left much to be desired. Regulations in effect from 1925 through 
1937, providing an open season from September 1 through September 
4 and a bag limit of 10 birds a day or 10 a season, actually stimulated 
butchery and injured sport. Hunting was allowed when birds were 
easily found, many being concentrated near patches of heavy cover 
near surface water. Unwary young of the year were easily shot be- 
cause they flushed near the gunner, flew straight and slowly for short 
distances, and ran but little after alighting. Adults performed sim- 
ilarly, probably because the weather was warm, the cover dense, and 
because they were in molt. September heat prohibited efficient work 
by bird dogs, so crippling losses were doubtless high. As it was 
also uncomfortably warm for men to walk, hunting by cars, and 
shooting from them, in violation of State law, became the rule in 
Colorado and Austin Counties and probably elsewhere in coastal 
Texas. 

In the future, the power of making regulations might well be 
delegated, under proper safeguards, to the State Game, Fish, and 
Oyster Commission, which has the benefit of information and counsel 



58 NORTH AMERICAN FAUNA 57, FISH AND WILDLIFE SERVICE 

from its own trained game protectors and from experienced sports- 
men, as well as from wildlife specialists connected with the State and 
Federal Governments. This power ghould allow for prompt modi- 
fication of regulations in response to emergencies of climate, or other 
conditions affecting the welfare of the birds. The proper open sea- 
son on Attwater's prairie chickens, assuming that the numbers of 
the birds can be built up to withstand the drain of shooting, cannot 
always be determined in advance, and regulations should be formu- 
lated in accordance with local conditions as they develop. The State 
legislature, meeting only at 2-year intervals, must rely on the State 
Game Commission for appropriate regulation of the take of game; 
and only under that arrangement can the people properly hold the 
Commission fully responsible for game protection. 

If hunting is again allowed, seasons should not in any case open 
prior to November 15. Weather late in November is usually suffi- 
ciently cool for the comfort of men and dogs, and, normally, the 
prairies are too wet to allow hunting from cars. The prairie chickens, 
already congregating in winter packs, are widely distributed and 
strong flying; consequently, they are hard to find and even more 
difficult to hit. Probably because the young of the year are strong 
and more worldly wise, and because the weather is cool and the 
ground cover reduced, late fall birds regularly flush widely, twist 
crazily, fly swiftly and far, usually for a mile or more, and run after 
alighting. In other words the Attwater's prairie chicken in Novem- 
ber is a game bird of the highest order; hunting it thoroughly tests 
the most skillful hunter and the best bird dog. That is as it should 
be in true sport. 

RESTOCKING 

At present the possibility that prairie chickens may be restored 
by artificial planting is remote, as wild birds are not available 
for trapping and moving, and artificial propagation has shown little 
promise. Furthermore, there is no assurance that priarie chickens, 
if available, would survive if moved. In Texas and Oklahoma, at- 
tempts to transplant lesser prairie chickens have been unsuccessful. 
Bent (1932: 263) records the failure of numerous attempts to trans- 
plant the greater prairie chicken in northern States. A number of 
these birds introduced in the vicinity of the Sault Sainte Marie and 
McMillan in northern Michigan persisted for a few years, but F. F. 
Tubbs, Michigan Department of Conservation, writes that they have 
disappeared. It is true that no intensive efforts have been made to 
transplant Attwater's prairie chickens in southern Texas, but there 
is no reason to believe that they would survive the process better 
than have their relatives. 



ATTWATER'S PRAIRIE CHICKEN 59 

Natural restocking, however, takeg place rapidly and efficiently 
when prairie chickens are properly protected and allowed to increase. 
Since 1935 practically all suitable territory in Refugio County has 
been restocked by natural spread from the Salt Creek Ranch and 
the properties of Martin O'Conner. When the birds are permitted to 
increase elsewhere, similar results may be expected. 

SUMMARY 

Attwater's prairie chicken, a characteristic bird of the coastal 
prairie, is one of three kinds that once occurred in Texas. A few 
lesser prairie chickens, smaller and paler in color than Attwater's 
subspecies, still persist in parts of the Texas Panhandle. The greater 
prairie chicken, however, has been entirely extirpated from its former 
habitat in the central and northern parts of the State. 

An intensive census made in the summer of 1937 revealed that 
only about 8,000 to 9,000 Attwater's prairie chickens then remained 
in Texas, approximately half of them being in Refugio County. 
The birds now inhabit only about 450,000 acres, compared with the 
more than 6,000,000 formerly occupied. The numbers of the coastal 
prairie chicken have declined 99 percent, and its range has decreasd 
more than 93 percent during the past century. 

The mating season begins late in January or early in February, 
when the males asgemble on short-grass areas early in the morning 
and late in the afternoon and boom and otherwise display the mating 
urge. Females are attracted to the courtship areas by this activity, 
and mating usually takes place there. Prairie chickens are pro- 
miscuous. The booming is at a climax in March and ends late in May. 

Nests containing eggs have been found from February 25 through 
June 17. The peak of the laying period, however, is late in March 
and in April. Females build their nests in dry vegetation of the 
previous year preferred nesting sites being in good cover in well-drained 
areas and within 5 yards of an opening. 

The normal rate of laying is 1 egg a day until the average clutch 
of 12 is completed, but intervals of 1, 2, and even 3 days are not 
infrequent. Subsequent attempts to nest may be made if earlier 
nestings are terminated while booming is still in progress. Second 
and third nests apparently are made in close proximity to those previ- 
ously destroyed, which probably jeopardizes their chances for suc- 
cessful termination. The incubation period is 23 to 24 days and 
hatching occupies about 2 days more. The peak of the hatching sea- 
son is in May. Fertility of the eggs evidently is high. Nest losses 
in 1937, however, were 70 percent of 13 nests studied, and those in 
1938 amounted to 67 percent of 6 nests. 

30.^07° — il 5 



60 NORTH AMERICAN FAUNA 5 7, FISH AND WILDLIFE SERVICE 

vin 1937, of broods on which accurate counts were obtained, 48 
averaged 5.48 birds each. Mortality of young prairie chickens is 
highest (about 50 percent) in the first 4 weeks after hatching and 
comparatively low (about 12 percent) thereafter, a large share of the 
early mortality being in lost chicks. Other known causes of juvenile 
mortality include heavy or persistent rains during the brooding, 
drowning in rice fields, and depredations by natural enemies. Fam- 
ily disintegration, although gradual, begins when the chicks are 6 
to 8 weeks old. It is completed after cold northers late in October 
and in November induce fall flocking, or segregation of the birds 
into flocks according to sex. 

Unstable and temporary groups of 5 to 15 birds are common from 
September through early October, but singles, pairs, and trios pre- 
dominate at that season. As fall passes into winter, flocks become 
larger, and in December and January groups containing 35 to 300 
individuals have been observed. Singles, pairs, and trios, however, 
may be found throughout the year. 

Young prairie chickens evidently spend their first 3 weeks within 
half a mile of the spot where hatched. Late in May and in June, 
both young and adults move to territory where cover providing good 
shade is found within half a mile of surface water, there to remain 
usually until September. When fall rains and cool weather come 
and the fall weeds mature, the birds scatter widely, often becoming 
common where scarce or entirely absent at other seasons. Concen- 
tration into areas where there is moderate-to-heavy cover and ade- 
quate food is evident by November, and populations in favorable 
areas fluctuate little from then through spring. 

The food of adult prairie chickens is about 85 percent vegetable 
matter and 15 percent animal. With young birds the ratio of vege- 
table to animal is approximately reversed. Favorite sources of plant 
food are ruellia, perennial ragweed, blackberry, doveweed, and sensi- 
tive briar. Leading animal foods are grasshoppers and beetles. 
Greens (leaves, flowers, buds) are lowest in the diet in November 
and December; seeds are taken in the smallest proportions in Jan- 
uary, February, and March. Insects are least frequently captured 
in November, December, and January. 

Important factors limiting prairie chicken abundance include ex- 
cessive or persistent rainfall during the nesting season, heavy graz- 
ing, excessive pasture burning, agricultural operations, and over- 
shooting. Other destructive factors, not generally serious but some- 
times locally disastrous, include oil development, drainage, floods, 
drought, hurricanes, hail, the spread of woody vegetation into prairie 
land, predation, pasture mowing, and possibly disease. 



ATTWATERS PRAIRIE CHICKEN 61 

Available records from 1925 through 1937 show a positive correla- 
tion on unmanaged land between the production of young prairie 
chickens and rainfall in May. Good crops of young chickens arie 
brought off in years when the rainfall in May is II/2 inches or more 
below normal. Fair broods are produced when precipitation in May 
is nearly, or only slightly above, normal, while poor crops are probable 
when rainfall in May is about twice normal. If the findings in 
Colorado County apply to other parts of the coastal country, 2 years 
in 5, on the average, are favorable to prairie chicken reproduction^ 
2 are fair, and 1 is poor. Conditions affecting reproduction are never 
the same for the entire range, for a county, or even for different parts 
of the same county, because of the scattered character of local rains. 
Attwater's prairie chicken is a highly fluctuating subspecies, its 
scarcity or abundance depending to a large extent on the precipita- 
tion in May. 

The annual kill of these birds cannot be intelligently regulated by 
such general open seasons and general bag limits as have applied 
in Texas in the past, but should be set, when permissible at all, by 
regulation by the State Conservation Department on the basis of the 
latest detailed information obtainable. 

Optimum prairie chicken range apparently consists of well-drained 
grassland supporting some weeds or shrubs as well as grasses, the 
cover varying in density from light to heavy; and with supplies of 
surface water available in summer. In short, diversification within 
the grassland type is essential. 

Management usually will involve protection against excessive kill- 
ing, improvement of food and cover, moderate control of predators, 
and wise regulation of the harvest. Responsibility for management 
must be assumed by the landowner. Food and cover deficiencies 
can best be recognized and their improvement and maintenance as-^ 
sured by careful counts of the birds on part, or all, of the managed 
area at three critical periods in March, July, and December. 

To obtain and maintain favorable food and cover, the following 
general practices are recommended: (1) Moderate grazing of pas- 
tures; (2) completing all necessary pasture burning before February 
1 and leaving unburned not less than 40 percent of the best drained 
ground ; (3) mowing pastures after July 1 and preserving the native 
cover on knolls, around ponds, and in flats; (4) allowing wind- 
mill tanks to spill over in summer to increase the supply of surface 
water; (5) controlling the numbers of feral house cats and predatory 
dogs; and (6) allowing the shooting of not more than 35 percent 
of the known prairie chicken population in any year when rainfall 
in May is normal or below and prohibiting killing when rainfall in 
May is approximately twice normal or above. Hunting seasons 
should not open before November 15. 



62 NORTH AMERICAN FAUNA 57, FISH AND WILDLIFE SERVICE 

Under normal conditions hawks, owls, and fur animals do not 
appear to be serious predators on Attwater's prairie chickens, and 
should not be killed indiscriminately. 

Persons should not request the Government to furnish prairie 
chickens for restocking, because there is no surplus for the purpose 
and no evidence that the birds can be successfully transplanted. 

In the absence of ample reservations for the species all other 
favorable factors together cannot be counted on to save the bird 
from extinction. Before too late a large tract or tracts of suitable 
range should be established as a prairie chicken refuge by the Federal 
or State Government. 

LITERATURE CITED 

AsKiNs, Charles C. 

1931. Game bird shooting. 312 pp., illus. New York. 
Bailhtt, Plobence Mebriam. 

1927. Handbook of birds of the western United States. Ed. 10, rev., 590 pp. 
illus. Boston and New York. 
Bailet, Vernon. 

1905. Biological survey of Texas. U. S. Biol. Survey North Amer. Fauna 
25, 222 pp., iUus. 
Bbndire, Charles Emil. 

1892. Life histories of North American birds with special reference to 

their breeding habits and eggs, with twelve lithographic plates. 
U. S. Nat. Mus. Special Bull. 1, 446 pp. 
1894. Tympanvchus americanus attwateri Bendire. Attwater's or southern 
prairie hen. Auk 11 : 130-132. 
Bent, Arthur Cleveland. 

1982. Life histories of North American gallinaceous birds. U. S. Nat. Mus. 
Bull. 162, 490 pp., illus. 
Brat, William L. 

1901. The ecological relations of the vegetation of western Texas. Bot. 
Gaz. 32:99-123, 195-217, 262-291, illus. 
Erkinoton, Paxil Lesthe. 

1935. Overpopulation and predation: A research field of singular promise. 
Condor 37: 230-232. 
Fisher, Albert Kenrick. 

1893. The hawks and owls of the United States in their relation to agri- 

culture. . U. S. Dept. Agr. Biol. Survey (Orn. and Mamin.) Bull. 
3, 210 pp., illus. 
Gkoss, Alfred Otto. 

1930a. The Wisconsin prairie chicken investigation. Amer. Game 19 : 39-40, 

50. 
1930b. Progress report of the Wisconsin prairie chicken investigation. Wis- 
consin Conserv. Comn. 112 pp., illus. Madison, Wis. 
Leopold, Aldo. 

1931. Report on a game survey of the North Central States. 299 pp., illus. 

Madison, Wis. 
1933. Game management. 481 pp., illus. New York and London. 
May, John Bichabd. 

1935. The hawks of North America. 140 pp., illus. Nat. Audubon Soc, 
New York. 



ATTWATER'S PRAIRIE CHICKEN 63 

McAtee, Waido Lee. 

1931. A little essay on vermin. Bird-Lore 33 : 381-384. 

1932. Confusions of an economic ornithologist. Bird-Lore 34 : 315-321. 

1935. Food habits of common hawks. U. S. Dept. Agri. Circ. 370, 36 pp., 

illus. 

1936. The Malthusian principle in nature. Sci, Monthly 42 : 444-456. 
and Stoddabd, Heobebt Lee. 

1930. American raptores and the study of their economic status. C5ondor 

32: 15-19. 
Mebkill, James Gushing. 

1879. Notes on the ornithology of southern Texas, being a list of birds 
observed in the vicinity of Fort Brown, Texas, from February, 1876, 
to June, 1878. U. S. Nat. Mus. Proc. 1 : 118-173, 1878. 
Obebholseb, Habey Church. 

1938, The bird life of Louisiana. 834 pp., illus. New Orleans. 
Simmons, George Finlay. 

1925. Birds of the Austin region. 387 pp., illus. Univ. Texas, Austin. 
Streckeb, John Kern. 

1927. Notes on the ornithology of McLennan County, Texas. Baylor Univ. 
Mus. Spec. Bull. 1, 65 pp. 
Stoddard, Herbert Lee. 

1931. The bobwhite quail: its habits, preservation, and increase. 559 pp., 

illus. New York. 
Taylor, Walter Penn. 

1934. Significance of extreme or intermittent conditions in distribution of 

species and management of natural resources, with a restatement 
of Liebig's law of minimum. Ecology 15: 374-379. 
Vorhies, Charles Taylor; and Lister, Paul B. 

1935. The relation of jack rabbits to grazing in southern Arizona. Jour. 

Forestry 33 : 490-498, illus. 
Texas Game, Fish, and Oyster Commission. 

1929. Grouse or prairie chicken. Ann. Rpt. 1929 : 86-91, illus. Austin, Tex. 
Tharp, Benjamin Carroll. 

1926. Structure of Texas vegetation east of the 98th meridian. Univ. Texas 

Bull. 2606, 100 pp., illus. Austin, Tex. 



f'r^ 



INDEX 



Abundance, 6, 7. 
Agricultural factors, 40. 
americanus, Tympanuchus, 4. 
attwateri, Tympanuchus cupido, 1. 

Brood size, 18. 

Call, 12. 

Cat, house, 38, 39, 40. 
Census methods, 47. 
Coloration, 4, 5, 6. 
Courtship, 10. 
cupido, Tympanuchus, 1. 

Development of young, 16. 
Disease, 36. 

Disintegration, family, 19. 
Distribution, 2, (map) 3, 7. 
Drainage, effect of, 43. 

Eagle, bald, 39. 

Flocking, 20. 
Floods, 35. 
Food, 25. 

Goshawk, 39. 

Grouse, 39. 

Growth of young, 16. 

Habitat, 30. 

control, recommendations, 56. 

improvement, 46. 

requirements, 30. 
Hawk, duck, 39. 

ferruginous roughlegged, 39. 

Krider's, 39. 

marsh, 39. 

rough-legged, 39. 
Heath-hen, 1. 
Hunting, effects, 44. 

Increase, 20. 



Limiting factors, 31. 

Management, 45. 
Mating, 10. 
Mortality, juvenile, 19. 

Nesting, 14. 

Nests, predation on, 37. 

Overgrazing, effect of, 42. 

pallidicinctus, Tympanuchus, 4. 
Pasture burning, effect of, 41. 

mowing, 43. 
Population status, 8. 
Prairie chicken, Attwater's, 1. 

greater, 4. 

lesser, 4, 5. 
Predation, 37. 
Predator control, 57. 
Protection, 45. 

Quail, 39. 

Rainfall, 32. 
Restocking, 58. 

Seasonal movements, 21. 
Sparrow, English, 17. 
Starling, 17. 
Storms, 35, 36. 
Surplus, 57. 

Turkey, bronze, 17. 

Tympanuchus cupido americanus, 4. 

cupido attwateri, 1, 4. 

cupido cupido, 1. 

pallidicinctus, 4. 

Weight, 5. 
Wolf, red, 38. 
Woody vegetation, 36. 

Young, development of, 16. 
predation on, 38. 



65 



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