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SURVEY

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TRENDS IN PHEASANT ABUNDANCE
IN ILLINOIS: 1958 te 1968

RONALD F. LABISKY

Biological Notes No. 65
ILLINOIS NATURAL HISTORY SURVEY
URBANA, ILLINOIS MAY, 1969

STATE OF ILLINOIS
DEPARTMENT OF REGISTRATION AND EDUCATION
NATURAL HISTORY SURVEY DIVISION

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Trends in Pheasant Abundance in Illinois: 1958 to 1968

The pheasant (Phasianus colchicus), first introduced
into Illinois about 75 years ago (Robertson 1958:3),
has established thriving populations in northern and
east-central Illinois. It has never established perma-
nent populations in the west-central and southern
counties of the state. Although the pheasant has ex-
hibited shifting patterns of population density within
its occupied range in the state, it has persistently
maintained its center of abundance in the cash-grain
region of east-central Illinois since the mid-1930’s ( Fig.
1; Greeley et al. 1962:13-16; Labisky & Anderson
1965:128). The rapid increase in the acreage of row
crops (corn and soybeans) in the east-central sector
of the state during the 1960's (Joselyn et al. 1968:
217-218) has resulted in a marked reduction of pheas-
ant nesting cover, particularly tame hay and small
grains. These land-use changes have adversely affected
pheasant abundance in this region (Labisky 1968:353-
389).

The purpose of this paper is to document the patterns
of distribution and abundance of pheasants in Illinois
for 1968 and to compare these findings with similar
statistics from 1958 and 1963. Some data from the 1958
and 1963 censuses have been presented, in part, in
previous publications (Greeley et al. 1962; Labisky &
Anderson 1965).

ACKNOWLEDGMENTS

The author extends his sincere appreciation to the
hundreds of postmasters and rural mail carriers in
Illinois who voluntarily participated in the 1968 and
previous pheasant censuses and whose cooperation was
outstanding.

Clifford Edwards, President (Enfield, Ill.), and
Vernon Maier, Secretary (Clifton, Ill.), Illinois Rural
Letter Carriers Association, offered advice in organiz-
ing the 1968 census. Officials of the U.S. Post Office
Department, M. L. Stover (Washington, D.C.) and
Donald L. Swanson and Norbert P. O'Donnell (Chica-
go), expedited the project in numerous ways.

William L. Preno, Illinois Department of Conserva-
tion, Springfield, and my Illinois Natural History Sur-
vey colleagues, William L. Anderson and Glen C.
Sanderson, read the manuscript. Richard M. Sheets,
Survey Illustrator, prepared the maps and designed
the cover. Robert M. Zewadski, Survey Associate
Editor, edited the manuscript. Dawn A. Labisky as-
sisted in assembling the materials for distribution to
the postmasters and rural mail carriers.

METHODS

Statistics on the distribution and abundance of
pheasants reported in this paper were voluntarily col-

This paper is published by authority of the State of Illinois, IRS
Ch. 127, Par. 58.12. Dr. Ronald F. Labisky is an Associate Wildlife
pf eee Section of Wildlife Research, Illinois Natural History Survey,

rbana,

Ronald F. Labisky

lected by rural mail carriers during 5-day census
periods in April of 1958, 1963, and 1968. These censuses
were restricted to the 74 northernmost counties of the
state; Greeley et al. (1962:14), after conducting a
statewide census in 1957, conservatively classified the
remaining 28 of Illinois’ 102 counties as nonpheasant
range. The censuses were conducted in April because
Greeley et al. (1962:5) concluded: “The conditions for
observing pheasants [in Illinois] are probably more
nearly constant from year to year in April than in any
other month.” The specific 5-day census periods
(Monday through Friday) were April 21-25 in 1958
and April 22-26 in 1963 and 1968. The daily census
period was between § AM and noon (CST) in all years.

Approximately 5 days preceding each of the cen-
suses, a packet of materials relating to the census was
mailed to the postmaster of each post office having
one or more rural routes in the 74 counties to be
censused. The packet contained a letter of instruction
to the postmaster and a letter of instruction plus a
postal-card questionnaire for each rural mail carrier,
The postmaster was requested to distribute the latter
to each of his rural carriers. Each carrier was asked to
report the counties and political townships in which his
route was located, the length of his route in miles, and
the number of pheasants (cocks and hens) observed
along the route on each of the 5 consecutive days
specified in the instructions.

The number of miles driven and the number
of pheasants seen during the 5-day census pe-
riod were used to calculate the number of pheasants
observed per 100 miles of driving in each township
and county. When the route of a mail carrier extended
into two or more townships, the number of miles
driven and number of pheasants observed were divided
equally among the number of townships that he re-
ported on his questionnaire. The variables that influ-
ence the counts of pheasants by rural mail carriers have
been discussed by Greeley et al. (1962:4-5).

The information reported by mail carriers during
each census was the result of the initial request only;
follow-up mailings to prompt the return of question-
naires were unnecessary (Table 1). To exemplify,
in 1968, 97 percent of all returned questionnaires had
been received by May l—only 5 days after the last day
of the census period. After each census all postmasters
and mail carriers participating in the census were sent
a summary of the census findings and a letter thanking
them for their cooperation.

FINDINGS

The relative abundance of pheasants in the 74 north-
ernmost counties of Illinois increased from 7.6 to 9.9
pheasants observed per 100 miles of driving (30 per-
cent) between April, 1958, and April, 1963, and then

declined to 5.5 birds per 100 miles (44 percent) by

4

Table 1.—Comparative statistics obtained from rural mail
carrier censuses of pheasants in the 74 northernmost counties
(including 1,257 townships) of Illinois during designated 5-day
census periods in April of 1958, 1963, and 1968.

Category April, 1958 April, 1963 April, 1968
Questionnaires

mailed 1,368 1,320 1,256

Number retumed __1,053(77)® —-:1,202(91) 1,143(91)

Number usable

(of total ) t 1,150( 87) 1,105(88)
Number of

townships

reported

(of 1,257) 1,221(97) 1,222( 97) 1,214(97)
Total miles driven 250,129 318,605 333,070§
Miles driven

per township

reported 205 261 268
Cocks observed 10,047 t 17,204 t 10,706
Hens observed 9,044} 14,466 7,545

Total pheasants

observed 19,0914 31,6704 18,251
Sex ratio:

hens per cock 0.9 0.8 0.7
Cocks per 100 miles 4.0 5.4 3.2
Hens per 100 miles 3.6 45 2.3

Total pheasants

per 100 miles 7.64 9.9 5.5

© Percentages are given in parentheses.

} Data are not available.

t These figures are slightly different from those appearing in Labisky
and Anderson (1965:129, Table 1); the figures in the earlier publica-
tion were in error.

§ 8,233 miles of driving were, for the lack of township designations,
assigned only to counties.

April, 1968 (Table 1). Statistics for hens only, em-
ployed to avoid sex-ratio differences among years, re-
vealed similar trends in abundance. The number of
hens observed per 100 miles increased from 3.6 in 1958
to 4.5 in 1963 (25 percent) and then declined to 2.3 hens
per 100 miles in 1968 (49 percent). Thus, pheasants
increased in abundance by about one-fourth between
1958 and 1963 and declined in numbers by almost one-
half in the succeeding 5 years, 1964-1968. Pheasants
were only about three-fourths as abundant in 1968 as
in 1958.

Although the overall trend in pheasant abundance
in Illinois during the past decade was downward, not
all portions of the occupied range suffered declines in
abundance. In fact, the pheasant range can be sepa-
rated into three major sectors with respect to changes
in abundance that have occurred within the past 10
years. The east-central portion of the state showed
substantial gains (about 50 percent) in abundance be-
tween 1958 and 1963; however, the marked decline
(about 60 percent) in abundance between 1963 and
1968 more than cancelled the earlier gains, resulting in
a net loss of pheasants in Illinois’ prime range (Table
2; Fig. 2-4). All counties of northern Illinois, except
Carroll, were characterized by substantial losses in
pheasant abundance between 1958 and 1968; the losses
incurred between 1958 and 1963 were particularly se-
vere. In contrast, the southern and southwestern por-
tions of the range occupied by pheasants in Illinois were
characterized by very substantial gains in abundance
between 1958 and 1968.

Table 2.—Relative abundance of pheasants as reported by rural mail carriers in the 74 northernmost counties of Illinois in
April 1958, 1963, and 1968. The remaining 28 counties, located in southern Illinois, are not occupied by pheasants.

Percentage Change

County Total Pheasants Pheasants Per 100 Miles
County Rank Reported Per 100 Miles a8 198 158
to to to

1958 1963 1968 1958 1963 1968 1958 1963 1968 1963 1968 1968
Livingston 1 1 1 3,634 8,181 3,006 56.4 99.1 33.3 +76 —66 —4l
Logan 16 N7/ 2 305 345 1,543 8.3 9.7 SLL +17 +221 +275
Ford 2 2 3 1,569 2,696 1,144 50.7 75.8 29.2 +50 —61 —42
Woodford Wf U 4 718 852 787 15.6 21.8 21.4 +40 —2 +37
Moultrie 37 15 5 27 301 Bede I Sry oe +707 +460 +1,193
Piatt 12 6 6 305 986 402 11.8 34.6 17.7 +193 —49 +50
McLean 4 4 7 2,071 3,868 1,324 27.7 43.1 17.0 +56 —61 —39
Champaign 5 5 8 1,641 3,018 1,371 25.7 35.6 16.8 +39 —53 —35
Iroquois °3) 3 9 1,991 3,674 1,373 28.9 43.4 ibsz¢ +50 —64 —46
De Witt 19 Vil 10 190 547 405 6.5 16.1 12.2 +148 —24 +88
Putnam 13 9 11 81 131 105 10.8 19.1 10.6 +77 —44 —2
Kankakee 8 8 12 706 973 538 15.3 19.7 10.1 +29 —49 —34
Vermilion 6 16 13 966 728 632 17.3 ili tsil 9.8 —36 —12 —43
Grundy 10 10 14 323 429 283 12.5 gi 9.3 +42 —47 —26
La Salle 11 14 15 873 1,233 820 12.4 13.8 9.1 +11 —34 —27
Douglas 15 13 16 204 487 244 8.7 14.3 8.6 +64 —40 —l
Macon 42 19 17 27 326 421 0.7 6.6 8.5 +843 +29 +41,114
Marshall 9 12 18 328 395 176 14.6 15.0 8.2 +3 —45 —44

De Kalb 14 2 19 367 261 396 10.4 5.2 8.0 —50 +54 —2
Tazewell 21 18 20 284 343 356 6.1 8.5 6.5 +39 —24 +7
Mason 30 20 21 66 148 184 2.7 5.4 6.4 +100 +19 +137
Edgar 24 24 22, 190 214 258 5.0 4.2 5.3 —16 +26 +6
Kendall 17 22, 23 135 131 148 7A 48 5.0 —35 t4 —32
Christian 52 32 24 9 67 204 0.2 1.2 3.5 +500 +191 +41,650
McHenry 18 25 25 280 200 183 7.0 3.9 3.4 —44 —13 —5l
Coles 31 29 26 60 86 128 2.0 2.3 Se) +15 +39 +60
Lee 20 26 hi 243 147 131 6.2 3.1 2.8 —50 —10 —55
Will 26 27 28 208 179 181 4.6 3.0 iy f —35 —10 —Al

The drastic decline in pheasant abundance in east-
central Illinois, which has harbored perhaps as many
as two-thirds of the state’s pheasant population during
the past 30 years, is of critical interest. In both 1958
and 1963, the east-central counties of Livingston, Ford,
Iroquois, McLean, and Champaign were, in that order,
the five top-ranked counties with respect to relative
abundance of pheasants (Table 2). The relative abun-
dance of pheasants observed in these counties, collec-
tively, was 37.9 and 59.4 birds per 100 miles in 1958
and 1963, respectively. In 1968, these same five coun-
ties had a collective relative density of 22.4 pheasants
per 100 miles, a decline of 62 percent from 1963. Fur-

5

thermore, by 1968 McLean, Champaign, and Iroquois
counties had slipped from their traditional positions
among the five top-ranked counties to occupy positions
7, 8, and 9, respectively. Notably, the only segment of
range in Illinois to register a measure of abundance
exceeding 100 pheasants per 100 miles of driving in
1958, 1963, and 1968 was that located at the junction
of Champaign, Vermilion, Douglas, and Edgar counties
(Fig. 24).

Northern Illinois, characterized by secondary centers
of pheasant abundance in the 1940's (Fig. 1), has, in
the intervening years, suffered a greater proportionate
loss in pheasant numbers than any other sector of the

Table 2.—( Continued )

Percentage Change

County Total Pheasants Pheasants Per 100 Miles
County Rank Reported Per 100 Miles [656 Te 168
by to to to
1958 1963 1968 1958 1963 1968 1958 1963 1968 1963 1968 1968

Menard 43 34 29 8 18 49 0.6 1.0 DS +67 +4130 +283
Boone 23 35 30 112 21 35 5 1.0 2:3; —80 +4130 —55
Ogle 35 Al 31 76 26 119 1.5 0.5 2.0 —67 +300 —33
Carroll 33 33 32, 40 39 65 19 iil 2.0 —42 +82 +5
Kane 28 28 33 116 98 67 3.6 2 Se —25 —37 —52
Sangamon AT 38 34 17 43 101 0.3 0.6 1n5: +100 +4150 +400
Cook 29 30 35 92 61 54 2.8 1.6 1.4 —43 —12 —50
Cass 53 36 36 4 18 32 0.2 0.8 1.2 +300 +50 +500
Du Page 25 23 37 93 117 35 49 4.3 12, —12 —72 —76
Lake 32 31 38 60 66 54 2.0 1.2 ila —40 —8 —45
Bureau 38 42 39 66 29 70 1.3 0.5 1.0 —62 +100 —23
Winnebago 36 37 40 46 22 39 es) 0.6 1.0 —60 +67 —33
Stephenson 22 44 Al 201 18 38 5.4 0.3 0.9 —94 +200 —83
Whiteside 48 47 42 15 13 39 0.3 0.3 0.8 0 +4167 +167
Shelby 54 39 43 11 35 40 0.2 0.5 0.7 +150 +40 +250
Morgan 57 48 44 2 5 14 0.1 0.2 0.4 +100 +100 +300
Mercer 55 43 45 2 15 14 0.1 0.5 0.4 +400 —20 +300
Henry 34 46 46 88 19 16 1.8 0.3 0.3 —83 0 —83
Montgomery 60 54 47 3 4 16 0.1 0.1 0.3 0 +200 +200
Jo Daviess 39 45 48 37 15 11 12 0.3 0.2 —75 —33 —83
Stark 27 40 49 63 9 7 4.2 0.5 0.2 —88 —60 —95
Macoupin® 59 50 0 1 8 0.0 0.0+ 0.1 —} et +
Cumberland 50 58 51 6 2 3 0.3 0.1 0.1 —67 0 —67
Fulton 64 52 1 0 5 0.0+ 0.0 0.1 — + aa
Rock Island 59 52 53 3 2 3 0.1 0.1 0.1 0 0 0
Peoria 46 49 54 16 6 3 0.4 0.1 0.1 —75 0 —75
Knox 62 57 55 2 3 2 0.0+ 0.1 0.1 + 0 +
Effingham 41 56 56 24 2 2 0.8 0.1 0.0+ — _ -—
Henderson 45 57 10 0 1 0.5 0.0 0.0-4 0 _
Hancock 58 0 0 2 0.0 0.0 0.0-+ 0 ee +.
Jasper 40 50 59 33 4 2 1.0 0.1 0.0+ _ — _
Warren 49 55 60 9 3 2 0.3 0.1 0.0-+4 — — —
Crawford 61 0 0 1 0.0 0.0 0.0+ 0 +- te
Adams 62 0 0 1 0.0 0.0 0.0-+- 0 + +
McDonough 44 63 19 0 1 0.6 0.0 0.0+- — + —
Bond 64 0 0 1 0.0 0.0 0.0+- 0 + +
Clark 56 51 65 3 5 1 0.1 O01 0.0+ 0 — —
Fayette 61 66 4 0 1 0.1 0.0 0.0+- _ + =
Clay 51 5 0 0 0.3 0.0 0.0 _ 0 —
Greene 58 53 2 3 0 0.1 0.1 0.0 0 _ —
Jersey 60 0 1 0 0.0 0.0+- 0.0 + — 0
Madison} 61 0 1 0 0.0 0.0+ 0.0 + _ 0
Pike 63 1 0 0 0.0+ 0.0 0.0 _ 0 —
Brown 0 0 0 0.0 0.0 0.0 0 0 0
Schuyler 0 0 0 0.0 0.0 0.0 0 0 0
Scott 0 0 0 0.0 0.0 0.0 0 0 0

° No rank was assigned to counties from which pheasants were absent in year of census. ; ;

+ Percentage change presented only as ++ (gain), — (loss), or 0 (no change) for those counties from which pheasants were reported absent

(including 0.0 + ) in any of the three census periods.
1 Richland County was censused in place of Madison County in 1958.

6

state’s pheasant range (Fig. 2-4). Although the pheas-
ant population in northern Illinois had already declined
by 1958, it diminished even more during the past
decade. The abundance of pheasants in all counties
of northern Illinois, except Carroll, diminished substan-
tially between 1958 and 1968; losses in abundance dur-
ing these 10 years exceeded 50 percent in Jo Daviess,
Stephenson, Boone, McHenry, Kane, Cook, Du Page,
Lee, Henry, and Stark counties (Table 2). Pheasant
populations in northern Illinois would have plummeted
even lower had not such counties as Carroll, Stephen-
son, Winnebago, Boone, De Kalb, and Ogle actually
registered gains in abundance between 1963 and 1968.

The most spectacular change in pheasant abundance
that has occurred in Illinois within the past decade has
been the increase in pheasant numbers in a block of
nine counties—Logan, Moultrie, De Witt, Macon,
Mason, Christian, Menard, Sangamon, and Cass—sit-
uated south and southwest from east-central Illinois.
Increases in abundance among these nine counties, all
of which had densities of more than one pheasant per
100 miles of driving in 1968, ranged from twofold to
sixteenfold during the 10 years, 1958-1968 (Table 2;
Fig. 2-4). Notably, two of these counties—Logan and
Moultrie—advanced from their respective county rank-
ings of 16 and 37 in 1958 to rankings of 2 and
5 in 1968; these advances in ranking were due not
only to gains in abundance recorded in the two
counties but also to declines in abundance in many of

oe 4

i il

ite

- feo Le i i
fi ile
ide

APRIL, 1958

PHEASANTS PER
100 MILES

MB 100! PLUS

50.1—100.0

10.1 — 50.0

1.1 —10.0

0.1 - 1.0

LESS THAN OI

Fig. 2.—Distribution and abundance of pheasants in Illinois
as mapped from township statistics obtained by a rural mail
carrier census, April, 1958 (after Labisky and Anderson 1965).
Counties below the heavy line were not censused.

Ba
(0)
naa
=]

the previously top-ranked counties. Several counties
that adjoin the nine-county sector, namely Piatt, Taze-
well, Edgar, and Coles, also posted substantial, though
proportionately smaller, gains in pheasant abundance
during the past decade.

No decisive spread of pheasants into unoccupied
range along the southern and western boundaries of
the contiguous pheasant range has occurred within the
past decade (Fig. 24). Yet pheasant abundance in
many segments of this so-called “marginal” range, par-
ticularly in the south, has increased in recent years. The
several small populations of pheasants beyond the con-
tiguous range could be precursory, self-maintaining
flocks, but are probably the artifacts of local releases
of artificially propagated birds.

DISCUSSION

Examination of records documenting the distribution
and abundance of pheasants since their introduction
into Illinois (Greeley et al. 1962), leaves little doubt
that the state’s all-time high in pheasant abundance
was attained in 1962 or 1963. This conclusion is sub-
stantiated by the fact that the calculated autumn kill of
cocks by hunters in Illinois was greater in these years—
989,000 in 1962, and 1,066,000 in 1963—than in any pre-
ceding or following year through 1968 ( William L. Pre-
no, Illinois Department of Conservation, unpublished ).
The low in pheasant numbers in Illinois during the past

ST
Bue =
tia (I

APRIL, 1963

PHEASANTS PER
_1OOMILES
100.1 PLUS
50.I — 100.0
10.1 -50.0

1 —10.0

0.1 — 1.0

LESS THAN O.I

Fig. 3.—Distribution and abundance of pheasants in Illinois
as mapped from township statistics obtained by a rural mail
carrier census, April, 1963 (after Labisky and Anderson 1965).
Counties below the heavy line were not censused.

UEUURE

il

decade occurred in 1966; the 1968 breeding * population In the 5 years following the pheasant high of 1963,
was estimated to be about 10 percent above that of the abundance of pheasants in Illinois declined by
1966 (William L. Preno, unpublished). about 50 percent. Much of this decline in abundance,

ge

|

4p |

Sek,
\ eae , c. +

ACOUPI

=)
foe P=

APRIL, 1968 -

PHEASANTS PER
100 MILES

ae 100.1 PLUS

Re 50.1 — 100.0

(MM) 10.1-S0.0

4 1.1-10.0

(i 01-10

[__] LESS THAN O1!

HAMILTON | WHITE

Fig. 4.—Distribution and abundance of pheasants in Illinois as mnERe sd from to Sat statistics obtained
by a rural mail carrier census, April, 1968. Counties b« 15 ow the heavy line were no ee snsus

8

particularly in the prime pheasant range in east-central
Illinois, resulted from the rapid decrease in acreages
of tame hays and other suitable nesting habitats. The
increase in acreages planted to the major cash-grain
crops, corn and soybeans, has brought about this de-
crease in nesting habitats (Labisky 1968:353-389;
Joselyn et al. 1968:217-218). The drought of 1964 de-
pressed pheasant production and also contributed to
the decline in abundance.

It is most unlikely that substantial gains in pheasant
abundance will occur in east-central Illinois in future
years unless there is a reversal of agricultural trends,
which seems most improbable. In fact, it is doubtful
that pheasants will be able to maintain existing popu-
lation levels for long under today’s farming practices.
To illustrate, the obvious fragmentation of Illinois’ good
pheasant range in 1968, as evidenced by the intersper-
sion of areas of lower pheasant abundance with those
of higher abundance (Fig. 4), suggests that further
declines in abundance will be forthcoming. Livingston
County, the top-ranked pheasant county in the state,
shows signs of being cleaved from northwest to south-
east by a trough of lower pheasant abundance. Other
top-ranked counties, notably Champaign, Iroquois, and
McLean, exhibited noticeable range fragmentation be-
tween 1963 and 1968 (Fig. 3 and 4).

In 1968 the only sector of pheasant range in the state
showing encouraging increases in pheasant numbers
was in that block of counties (Logan, Moultrie, De
Witt, Macon, Mason, Christian, Menard, Sangamon,
and Cass) constituting the southwestern portion of IIli-
nois’ occupied pheasant range. Gains in pheasant num-
bers in this area, much of which was classified as medi-
ocre to poor with respect to abundance as recently
as the early 1960's, were unusually great (Table 2; Fig.
2-4). In fact, within this sector of pheasant range a
secondary center of abundance has appeared in north-
ern Logan County. Not only did this southwest sector
of range contain more pheasants in 1968 than it ever
had, but it also contained the highest density of pheas-
ants ever recorded along such a broad front so far
south in Illinois. Similarly, a surge in pheasant abun-
dance, beginning in the late 1950's, occurred in an area
of traditionally poor pheasant range in southwestern
Iowa (Klonglan 1962); this buildup in pheasant num-
bers has already persisted for a decade.

A decisive southward shift in pheasant abundance
has occurred in Illinois from 1948 to 1968. Northern
Illinois, which contained strong secondary centers of
pheasant abundance in the late 1940's, had, by 1968,
exhibited greater proportionate declines in pheasant
numbers than any other major region of the state. As
pheasant abundance declined in northern Illinois, it
increased in the prime range of east-central Illinois—
reaching an all-time high about 1963. Yet in 1968, east-
central Illinois, despite sustaining a 60-percent decline
in the pheasant population from that of 1963, still con-
tained the state’s center of pheasant abundance as it
had in the preceding 30 years. However, during the
1960's a comparatively spectacular gain in abundance
occurred in a large and contiguous segment of range

(4-90587—5M—5-69 )

located south-southwestward from east-central Illinois
and north of the southern boundary of the contiguous
pheasant range in Illinois. If pheasant abundance con-
tinues to dissipate in east-central Illinois as a result of
current agricultural practices, the southwestern portion
of range may replace east-central Illinois as the state’s
center of pheasant abundance. Even though popula-
tion abundance has increased along the southernmost
boundary of the pheasant’s range in Illinois in recent
years, there has been no real southward extension of
the bird’s range in the state.

SUMMARY

The relative abundance of pheasants per 100 miles
of driving in the 74 northernmost counties of Illinois,
as reported by rural mail carriers during April censuses,
was 7.6 in 1958, 9.9 in 1963, and 5.5 in 1968. Thus,
pheasants increased in abundance by about 30 percent
between 1958 and 1963 and then declined by about
44 percent between 1963 and 1968. The all-time high
in pheasant abundance in Illinois was probably reached
in 1962 or 1963.

Although the number of pheasants in Illinois has de-
clined during the past decade, not all portions of the
state’s pheasant range have suffered similarly. Pheasant
abundance in east-central Illinois, the state’s prime
pheasant range since the 1930's, increased about 50
percent between 1958 and 1963 and then declined by
about 60 percent between 1963 and 1968. Pheasants
in northern Illinois were less than half as abundant in
1968 as in 1958. In contrast, a severalfold increase in
pheasant abundance occurred between 1958 and 1968
in a large, contiguous unit of range immediately south-
southwestward from east-central Illinois.

Notably, Illinois has experienced a significant, pro-
gressive southward shift in pheasant abundance within
the past 20 years. Yet, despite the recent surge in pheas-
ant abundance in the southern portion of the range
occupied by pheasants, there has been no permanent
southward extension of the birds’ range in the state.

LITERATURE CITED

GREELEY, FREDERICK, RoNALD F. Lasisky, and Stuart H.
Mann. 1962. Distribution and abundance of pheasants
in Illinois. Illinois Natural History Survey Biological
Notes 47. 16 p.

Josetyn, G. BLam, JOHN E. WaRNocK, and STANLEY L. Etter.
1968. Manipulation of roadside cover for nesting
pheasants—a preliminary report. Journal of Wildlife
Management 32(2):217—233.

KLONGLAN, EuGENE DAWAyYNE. 1962. Ecology of pheasant
production in southwestern Iowa. Ph.D. Thesis. Iowa
State University of Science and Technology, Ames. 343 p.

Lapisky, RonaLp F. 1968. Ecology of pheasant populations
in Illinois. Ph.D. Thesis. University of Wisconsin,
Madison. 511 p.

Labisky, RONALD F., and WitittaM L. ANDERSON. 1965.
Changes in distribution and abundance of pheasants in
Illinois: 1958 versus 1963. Illinois State Academy of
Science Transactions 58(2):127—135.

Robertson, WILuiAM B., JR. 1958. Investigations of ring-
necked pheasants in Illinois. Illinois Department of
Conservation Technical Bulletin 1. 137 p.

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