CREEL CENSUS ON THE UPPER MISSISSIPPI RIVER SPECIAL SCIENTIFIC REPORT- FISHERIES No. 202 UNITED STATES DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE SERVICE EXPLANATORY NOTE The series embodies results of investigations, usually ol restricted scope, intended to aid or direct management or utilization practices and as guides for administrative or legislative action, it is issued in limited quantities for official use of Federal, State or cooperating agencies and in processed form for economy and to avoid delay in publication Representatives from the States of Illinois, Iowa, Minnesota, Missouri and Wisconsin and from the United States Fish and Wildlife Service, meeting in December, 1943, formed the Upper Mississippi River Conservation Committee for the purpose of carrying on scientific investigations of the fishery and wildlife resources of the Mississippi River from Caruthersville, Missouri, to Hastings, Minnesota. Field operations were started in 1944. United States Department of the Interior, Fred A . Seaton, Secretary Fish and Wildlife Service CREEL CENSUS ON THE UPPER MISSISSIPPI RIVER By John Greenbank Olathe, Colorado Contribution of the Upper Mississippi River Conservation Committee Special Scientific Report- -Fisheries No. 202 Washington, D. C. March 1957 ABSTRACT Two summer and two winter seasons of creel census on the section of the Upper Mississippi River, between Red Wing, Minnesota, and Dubuque, Iowa, in 1944-46, showed the catch to be about 0.5 fish per hour, with a wide variety of fish represented, crappies, bluegill walleye, and sauger being predominant. The fishery is important especially to the local fishermen. The fishing success was about the same in the winter as in the summer. Wide fluctuations occurred from one locality to another, and from week to week. Fishing success varied from year to year; it was better in 1948-49 than in 1944-46. The catch per hour was influenced by several factors, such as bait, time of day, day of the week, sex of the fisherman, and probably water temperature (in the summer) and depth of snow cover (in the winter). For most practical purposes, and in the interests of economy of data- gathering, the sample size could be reduced; it is suggested that a census conducted on every fifth day would give results reliable enough for practical management purposes. CONTENTS Page Introduction 1 History 1 The project 2 Acknowledgment 2 Description of Upper Mississippi River 3 General topography 3 Navigation pools 4 Characteristics of the fishery 4 Fishing methods 4 Kinds of fish 4 Quantitative aspects 5 Trends 5 Methods 6 Field operations 5 Report form s 5 Tabulating procedures 5 General figures 7 Number of returns 7 Fishermen, trips, and hours 7 Residence and distance travelled 7 Catch composition 10 Species composition of catch jq Composition by seasons, pools, and localities 10 Fishing success 22 Definitions and terms 22 Success by seasons 22 Success by localities 22 Variation throughout the season 27 Comparison of two years 3 1 Influence of certain factors 35 Fishing pressure 35 Bait 35 Time of day 37 Sex of fishermen 37 Water temperature ; 37 Changes in water levels 39 Weather, moon phases, etc 41 Depth of snow 41 Relationships and correlations 42 Two successive years 42 Sampling at intervals 45 Possibilities for reducing the size of the sample 51 Summary 57 Literature cited gg FIGURES Figure 1 . Day-to-day fishing success, summer of 1945 (total, all pools). Curve smoothed. Figure 2 . Week-to-week fishing success, summer of 1945, Pool 4 -L and Pool 10, and total (all pools) . Figures. Lower curve Day-to-day fishing success, winter of 1944-45 (total all pools). Curve smoothed. Upper curve - depth of snow on ground at La Crosse weather station. Figure 4. Week-to-week fishing success, winters of 1944-45 and 1945-46 (total all pools) . Figures. Week-to-week fishing success, Gremore Lake, winters of 1944-45 and 1945-46. Figure 6. Week-to-week fishing success. Pool 8, summers of 1944 and 1945. CREEK CENSUS ON THE UPPER MISSISSIPPI RIVER Introduction History. The Upper Mississippi River Conserva- tion Committee was organized in 1943, for the purpose of making a study of the fish and fishery of the Upper Mississippi River, where it forms a common boundary between the states of Minne- sota, Wisconsin, Iowa, Illinois, and Missouri. Extensive and intensive investigations were con- ducted from 1944 to 1949 and on a reduced scale since 1950, under the direction of a Technical Committee for Fish. The creel census operations herein reported were carried out under the auspices of this technical committee, and the supervision of the writer . A creel census was conducted on the Up- per Mississippi River in the area between Red Wing, Minnesota, and Dubuque, Iowa, during the summer of 1944, the winter of 1944-45, the sum- mer of 1945, and the winter of 1945-46. Fishery investigators familiar with the literature on the subject of creel census are a- ware of both the advantages and shortcomings of this method of estimating a sport fish harvest. The technique can be said to be almost standard- ized. It is one of the few reliable methods of assaying a sport fish harvest, and in some in- stances it seems to be the only feasible approach. Even so, it is at best a cumbersome procedure, and an expensive one . In the present instance, the technical committee deemed the operation a justifiable one. The need was great for concrete knowledge of the game fish yield of the Upper Mississippi River. It was known that this water furnished fishing sport to thousands of people, even in competition with the renowned fishing in lakes and trout streams in the area. But only a general notion was available of the size of the fishery. Accordingly, a creel census was decided upon, set up, and carried out as hereinafter described. The design was flexible, since the organization of the Mississippi River Survey necessitated the making of field activity plans for a season at a time. Nevertheless, since four successive fishing seasons (two winter seasons and two summer seasons) were involved, the re- sults obtained lend themselves handily to integration, and permit making certain compari- sons of the four seasons. The desirability of a continuation or repetition of the creel census work, in the years after 1946, was readily apparent; but the urgency of other projects of general fishery investigation necessitated the suspension of extensive creel census work.i' Therefore, it is only in a rough manner that comparisons of fishing harvest throughout a period of several years can be made . Casual observation indicated that the average fish- ing success was greater in the years 1948 to 1950 than it was in the period 1944 to 1946, when the creel census here reported was performed. The number of fishermen utilizing the river increased markedly, no doubt partly on account of the better fishing. Therefore, the total game fish harvest increased in a sort of geometric proportion. It is difficult to estimate long-range trends. In making any comparisons of fishing suc- cess factors between the Upper Mississippi River and other fishing areas, it must be remembered that the figures here presented for the Mississippi River may or may not represent averages over a long period of time . Apparently they do not, but instead they show fishing at low ebb. Generally it is futile to compare one fishing area with an- other in terms of average fishing success, even though these figures may have been faithfully recorded. Modifying factors are many. The kinds of fish entering the respective catches, the sizes and fighting qualities of the fish, the in- dividual preferences of the fishermen, and the day-to-day and season -to -season changes in fish- ing success, all make it difficult to say categorically that one water is a better place to fish than another. For this reason a complete 1/ In the years since 1950, a considerable amount of creel census work has been done, mostly in local areas, on the Upper Mississippi River, by the Upper Mississippi River Commit- tee or its member state agencies. Some of this work has been reported in the annual proceedings of the Committee; part of it is yet to be reported. review of the published literature on creel cen- sus, particularly in regard to quantitative re- sults, is not undertaken here. The Project. In the summer of 1944, creel census operations on the Upper Mississippi River were confined to the area adjacent to La Crosse, Wisconsin. This included most of pool 8 and a good share of pool 7 (the navigation pools on the Upper Mississippi River are described below) . The project was carried out in part with the voluntary cooperation of the Badger State Sportsmen's Club of La Cross, and sever- al sporting goods stores and boat liveries . However, Ihe bulk of the data was actually ob- tained by a creel census clerk working for the Upper Mississippi River Conservation Commit- tee . The field work extended from May 15 to September 30, with some intermittent work in the month of October . Almost the complete sum - mer and fall fishing season was covered. The winter census of 1944-45 was much more extensive. Five to 6 men were employed, and the river between Bay City, Wisconsin and Prairie du Chien was covered. The duration of this census was from mid-December to the end of February, which period included nearly all of the winter fishing. The census of the summer 1945 was still more extensive. Eight to 10 field men were em- ployed, and the territory stretched from above Red Wing, Minnesota to Dubuque, Iowa, a river distance of some 225 miles. The period of op- erations was from early May to the end of October. Although these 3 successive operations involved different total mileages of territory, they were similar in the degree of coverage . Each operator had a large territory assigned to him, and could not reach each part of it or con- tact each fisherman on any given day, particular- ly since the bulk of the fishermen left the river at about the same time toward the close of the day . Therefore, a system of rotation was used whereby the operator worked one fishing spot on one day and another on the next . Although the intent was to maintain this rotation on a random basis, some of the men developed rather set habits of visiting a certain place on a certain day of the week . This procedure likely had the effect of reducing the randomness of the sample, which effect will be discussed further in follow- ing sections. According to the field men, coverage ranged from 30 to 60 percent of the total fishing effort; in general, this figure was confirmed by the airplane fisherman counts. The data ob- tained represented a good cross section of the total fishing, and by their bulk, comprised a sample from which reasonable accurate averages can be derived. The census of the winter 1945-46 was re- duced in scope to a spot-check procedure. Three field men were employed, stationed at 3 key spots. Lake Pepin, La Cross, and Prairie du Chien . To a much greater degree than in the summer, the winter fishing is concentrated in particular small areas. Thus it was possible for the creel census operation in the winter of 1945-46 to get good day-to-day coverage of any given fishing spot, although the coverage of the entire river was less complete. Acknowledgment . The help of a great many in- dividuals and agencies is gratefully acknowledged. The Upper Mississippi River Conserva- tion Committee, consisting of representatives of the states of Minnesota, Wisconsin, Iowa, Illinois and Missouri, and the U.S. Fish and Wildlife Service, sponsored the work and provided for its being carried out. The Conservation Departments of Minnesota, Iowa, and Wisconsin provided the necessary personnel and money. The Badger State Sportsmen's Club of La Crosse formally participated in the summer census in 1944. Many of the club's officers and members, including particularly Alfred W . Rice and Walter Weigent, assisted in collecting filled field forms . Several boat liveries and resort operators filled out and submitted field blanks. Among these were the Copeland Park Boat Livery, Henry Rybold, and Haderer's Landing, all of La Crosse. Reports also were collected and submitted by some of the sporting goods stores, including especially Doerre's Hardware and the S. & H. Sport Shop of La Crosse. Many individ- ual fishermen filled out blanks voluntarily. In the summer census of 1945 and the 2 winter censuses, help was obtained from many boat liveries and resorts. Some of these were: Wines' Resort at Harpers Ferry;. Camp Lacupolis; Bass Camp; MerricK State Park; Kenny's Boat Livery at Guttenberg; Clements' Barge at Genoa; and many others. Valuable publicity was given to the proiect by the various newspapers in the river towns . The men employed as creel census field men deserve special mention. From first to last, these men did a thorough and conscientious job of conducting the census . They worked through irregular hours, without respect of holidays, and in all extremes of weather. En- gaged in one or more of the 4 separate projects were: Vilas D. Balk, Harold E. Beck, I. H. Boomer, Leonard Byer, Harold Elser, Laurence Hiner, Ralph Hunt, E B. Kolcinski, Edwin C. Larson, Paul McLaughlin, Walter Myhrom, Robert Sharp, William Sadewasser, and Lloyd Wyman . Much aid in working out tabulation pro- cedures was given by the personnel of Interna- tional Business Machines Corporation, particularly by W. G. Ekman of Minneapolis, and P.J. Spinnler of Milwaukee . Katherine Roeder and Bettie Satek assist- ed with the computing and tabulating of data; the drafting was done by Orvie Wetzel, Jr . ; and stenographic work by Drusilla Linnell . Description of the Upper Mississippi River General topography. The term "Upper Missis- sippi River", as used by the Upper Mississippi River Conservation Committee, refers to that part of the Mississippi River where it forms a common boundary between the states of Minne- sota, Wisconsin, Iowa, Illinois, and Missouri; i.e., the stretch of the river between the mouth of the St . Croix River and the mouth of the Ohio River. This is a distance of 810 river miles. The portion of the Upper Mississippi River which is dealt with in this report is the stretch between the Red Wing Dam and Dubuque, Iowa, a river distance of some 225 miles . Throughout most of this area, the river valley is bordered by abrupt rocky bluffs. The stream is strongly attenuated and there are numerous sloughs and side channels. There are many so-called lakes which are backwaters usually broadly connected with the river. The entire river valley varies from 2 to 10 miles in width, the total width of the water surface (main channel plus subsidiary channels) runs from 1 to 4 miles. The gradient is small, the total drop in the 225 miles being only 83 feet. The mean dis- charge at Red Wing is about 2500 c.f.s., and at Dubuque about 4500 c.f.s., there being several good-sized tributaries between. The river dis- charge, and correspondingly the water level, varies considerably througjiout the year. The usual high -water period is in the spring and early summer, with the water level ordinarily being low and stable throughout the late summer, fall, and winter. Because of the small amount of fall in the land, changes in the water level strongly alter the physical characteristics of the sloughs and backwaters . Any given fishing site, therefore, is far from a uniform piece of water the year around. The fishing activity is well localized at certain sites and many other stretches of water are scarcely utilized for fishing, either because they do not seem to the fishermen to be suitable or because they are difficult of access and are relatively unexplored. Also, simple gregarious- ness tends to concentrate ice fishermen. The various topographical types offer a corresponding variety of fishing conditions. These vary from the almost stagnant and usually shallow water of the backwater lakes, to the much deeper and swifter water in the main channel. Water temperatures run about the same course as those in the waters of the general region, except that, throughout the 225 miles of river, the water temperatures at any given time are remarkably uniform . Turbidity of the water varies from the reasonably clear water of fall and winter to ex- tremely muddy water during flood stage . Soft bottom with much silt and sand deposition is the rule, even in the larger flowing channels. A quantitatively good bottom fauna exists, however, and forms an important link in the fish food chain . Navigation pools. There are 26 dams between St. Paul and St. Louis, each of which is capable of shutting off temporarily almost the entire flow of the river. Each of these dams is by -passed by a lock for the use of river traffic . These dams, built in the period 1934-1940, create im- poundments, the purpose of which is to provide depth of water for boat passage. The impound- ments have a profound effect upon such factors as water levels, current, silt deposition, etc., and therefore upon the fish population and the fishing. An investigation of the changed con- ditions brought about by impoundments forms an important part of the work of the Mississippi River Fish Survey. This series of dams furnishes a neat artificial system for designating geographical units of the river, since the dams are numbered. This numbering system has been adapted to the creel census operation and will be used in this report . Briefly, the entire area of the river be - tween any 2 successive dams carries the same number as the lower (downstream) of the 2 dams. Thus, "pool 10" designates the stretch of the river, including all backwaters and side channels contained therein, between dam 9 and dam 10. In the 225 miles of river under discussion here, pools 4, 5, 5A, 6, 7, 8, 9, 10, 11, and part of pools 3 and 12 are included. These pools are very unequal in length and consequently in area . For instance, pools 5 and 5A are about 15 miles and 10 miles long respectively, while pool 10 is 33 miles long and pool 4 is 43 miles long, in- cluding the 22 miles of Lake Pepin. Orientation can be obtained by reference to a map of this part of the river, remembering that pool numbers go from upstream to downstream . To spot a few principal localities it may be mentioned that Red Wing is in the upper end of pool 4, \Wnona is in pool 6, La Crosse is in pool 8, Prairie du Chien is in pool 10, and Dubuque is at the extreme head end of pool 12 . Lake Pepin, although part of the river proper, has many of the properties of an actual lake. It has little current and toward its lower end is up to 30 feet in depth. It has a sigmoid shape and is about 22 miles long by 1 to 3 miles wide. Lake Pepin carries the entire flow of the river, there being no side channels paralleling it. In order to separate Lake Pepin from the remainder of pool 4, some of which exists as river above and below the lake, it has been as- signed an arbitrary number in the pool -number- ing system. Throughout this report Lake Pepin is designated as "pool 4-L" and the balance of pool 4 is called "pool 4-R". This is unofficial nomenclature not to be found on maps or charts. Characteristics of the fishery Fishing methods . As would be expected on a fishing water of this size and with various types of topography and a variety of fish to be caught, there is a considerable variation in the kinds of tackle and angling methods employed. Almost all of the common types of tackle are used, in- cluding cane poles, fly rods, bait casting rods, etc. In quantitative terms, however, at least 90 percent of the fishing is done by "still -fishing" methods, i.e., with a pole and line in the sum- mer and with a simple line rig in the winter. There is a growing tendency however, toward the use of bait and fly casting equipment. In the matter of bait, the preponderant use is of live bait - usually minnows or angle- worms. Artificial baits such as flies, plugs, and spinners, find limited use. Some of the fish- ing, such as that for carp or for catfish, uses various kinds of so-called natural materials such as dough balls, cheese, "stink baits", blood, shrimp, crayfish, cut fish, etc. The catch varies both as to quantity and as to kinds of fish with the bait used. For in- stance, most of the blueg^Us are caught on worms, while most of the crappies, bass, and walleyes are caught with minnows. Thus the type of bait used by the mai ority of the fishermen varies from one fishing locality to another in the same pattern that the kinds of fish fished for and taken vary by localities. Kinds of fish. The Upper Mississippi River offers an amazing variety of sport fishes . In this lies a good part of its popular appeal as fishing water, the supposition of the fisherman being that if one kind of fish isn't biting he can fish for something else. Especially is this true of the spring and summer fishing; the fall fishing and the ice fishing are limited to fewer varieties. In tlie total catch m the summer of 1945, some 19 kinds of fish (counting the 2 species of crappie as 1 kind) were recorded. Of these the following 12 kinds were commonly entered on the records: Bluegill (Lepomis macrochirus . An occasional pumpkinseed, Lepomis gibbosus, or green sun- fish, Lepomis cyanellus, was caught; and these were entered with the bluegills as "sunfish"), crappie (Pomoxis annularis and Pomoxis nigro- maculatus), walleye (Stizostedion vitreum), sauger (Stizostedion canadense), channel catfish (Ictaluris punctata s), flathead catfish (Pilodictus olivaris), bullhead (most commonly Ameiurus nebulosus, but Ameiurus na talis and Ameiurus melas represented), black bass (largemouth bass, Micropterus salmoides, being much more common than smallmouth bass, Micropterus dolomieu), white bass (Morone chrysops), drum (Aplodinotus grunniens), carp (Cyprinus carpio), and yellow perch (Perca flavescens) . These are listed roughly in the order of their abundance in the catch. About half of the total catch is made up of bluegill and crappie. In the fall fishing the emphasis shifts to walleyes and saugers, although bluegills and crappies still bulk large in the catch . Winter fishing is more specialized than summer fishing and involves fewer kinds of fish. In many of the areas, particularly those in pools 6 to 11, most of the winter catch consists almost entirely of bluegills and crappies. In Lake Pepin and the parts of the river adjacent to it, the principal winter fishing is for walleyes and saugers. Quantitative aspects. The sport fishery on the Mississippi River between Red Wing and Dubuque is one of considerable magnitude and importance even when viewed in comparison with the tre- mendous amount of fishing on the lakes and streams of Minnesota and Wisconsin. The resi- dent population of the cities and towns along the river is conscious of the recreational opportun- ities afforded by the Mississippi River and takes advantage thereof. ITiere are many ardent fish- ermen who use almost every opportunity afforded them to go fishing, and who may be seen out on the water weekend after weekend throughout the entire season. Another class goes fishing on special occasions such as holidays and vacations . Also, the fishing draws heavily upon the sports- men resident in the counties adjacent to the Mississippi River, even in competition with the fairly good trout fishing which some of these counties afford. The exact estimation of the total fishing effort and fish harvest is exceedingly difficult. Two (juantities are involved: the numbers of fishermen and the average individual catch. As already mentioned, both of these vary from sea- son to season and both can be determined only by costly and tedious procedures, even for a single season. The creel census under present discus- sion furnishes only a starting point for making estimates. Some rough estimates of the total fish harvest, for the period 1945-1949, are presented here in order to give an indication of the relative magnitude of the fishery. In this 225 -mile stretch of the Mississippi River, the 5 years, 1945 to 1949 had an average of about 150,000 fishermen during the summer season and about 25,000 dur- ing each winter season. The summer figures probably rose from about 60,000 in 1945 to about 250,000 per summer in 1948 and 1949. The win- ter figures held fairly steady, with perhaps some increase in the winters of 1948 and 1949. EXiring this 5 -year period, the total catch for the summer season ran possibly as loAv as 120,000 fish (in 1945) and possibly as high as r; 1,000,000 (in 1948 and in 1949) . The total winter catch was perhaps 40,000 fish per season from 1945 to 1948, increasing considerably in 1949. The total water area (at normal water stage) for this stretch of the river is approximate- ly 170,000 acres. A catch of one million fish in a year therefore would mean the removal of about 6 fish per acre. However, the actual fishing is confined to a small proportion of the total water acreage . Trends . There apparently is a trend toward more and more fishing on the Upper Mississippi River. There are two main factors involved. The first of these is the general and widespread increase in fishing interest and activity in t±ie country. The other factor applies specifically to the water involved, which has gained considerably in reputation as a fishing area . Rumors of good fishing are a powerful magnet to attract fisher- men. This tendency for good fishing to bring about an increase m numbers of fishermen has been mentioned by others, such as Eschmeyer (1942) and Frey and Vike (1941). the census clerk recorded only the number of hours that the fisherman had been fishing up to the time of the interview, as well as the parts of the day involved (morning, afternoon or evening) . Thus, all of the data can be expressed in terms of catch per fisherman-hour . In the event that the fishing of more than one person was entered on a single census form, as often was the case, someone of the fishing party acted as spokesman for the group . Methods Field operations. The field technique which was used followed in general the conventional method of creel census operation. With the exception of a comparatively few returns which were submit- ted voluntarily by the fishermen and routed through boat liveries or sporting goods shops, the data were recorded by personal interview with the fishermen by an employee of the survey (or in some instances by a boat livery or resort operator) . In the summer work part of the contacts were made by boat or foot travel and the fisher- men were interviewed while fishing. A large percentage of the contacts were made at boat liveries and landings as the fishermen came in from their fishing trips. In the winter work, contacts were made on the ice at the actual fish- ing site . The winter fishing did not consist en- tirely of ice fishing however; a small amount of fishing was done in open water below the dams. This open -water fishing has not been separated from ice fishing in the tabulations of the data. The necessity of covering several fishing localities each day required the use of consider- able travel by automobile, which added to the expense of the operation. Also, a large amount of traveling was done by motorboat which, al- though slower than an automobile, permitted access to more out-of-the-way fishing spots. Report forms . A separate field data form was used for each of the 4 separate seasonal projects but in reality these represented only modifica- tions of a generalized form used by many other creel census workers. The changes from one season to the next were mostly in the nature of simplification since it appeared that certain in- formation was relatively nonessential and could be dispensed with in favor of covering more ground. The principal items on the field form were: the locality and pool number; the date; the time of day fished; the number of men and number of women in the fishing party; the number of hours fished; and the catch in terms of Kinds of fish and number of each kind. An effort was made to carry out the inter- views as nearly as possible at or toward the end of the day's fishing for each individual fisherman, in order to secure information concerning the length of the average fishing period. Since many of the fishermen quit fishing only at the end of the afternoon or (in the summertime) of the eve- ning.a large share of the contacts had to be made late in the afternoon or evening. The field men, however, attempted to make a certain number of contacts in the morning or at mid-day to catch the early -bird fishermen and to secure informa- tion regarding variance of fishing success with the time of day. In any event, whether or not the fisherman had concluded fishing for that day. The field forms were printed on cards which were carried loose by the field operators and later were assembled in file boxes. An at- tempt was made to design the printing of this form so that the recorded information could readily be handled by punchcard tabulating tech- nique. This attempt was only partially successful. Tabulating procedures . Part of the sorting and tabulating of the collected data was done by hand methods and part of it by I. B. M. electric punch - card technique. It was found that a number of serious errors were made during the card-punch- ing process, and therefore much of the electric tabulating work had to be rechecked by hand later . This led to the conclusion that punchcard tabula- tion of a set of data such as these is worthwhile only if errors are minimized by use of the punch - verification process. General figures Number of returns. Table 1 gives some of the general statistics of the 4 seasons of creel cen- sus . Slightly fewer than 500 cards were returned by the census of the summer of 1944. The sum- mer of 1945 being much more extensive, yielded almost 14,000 returns. The two winter seasons averaged about 3,000 cards per season. The field work of the census (excluding all supervisory work) cost the participating agen- cies about $10,000. At this rate, each of the 20,000 cards cost approximately 50 cents. Fishermen, trips, and hours. The 20,000 cards represented a total of about 40,000 fisherman- trips . The numbers of men and women whose fishing activities were recorded are itemized in table 1. Minors of 15 years or older were separated as to sex and included in these figures; children under 14 were not counted. In the two summers the percentage of women was 14 and 17 respectively. In the win- ter fishing this figure dropped to 5 percent. Evidently the members of the gentler sex prefer to do their fishing when the weather is less rugged. Each card represented, on the average, about 1.7 fishermen in the summer fishing, and about 2.3 fishermen in the winter. The differ- ence probably is significant. Winter fishing is a more gregarious sport than is summer fishing. Not only are the fishermen more closely congre- gated in regard to locality, but also the average "fishing party" (upon which an individual card was based) tends to be larger. The total number of person-hours of fishing (table 1), when divided by the corresponding total numbers of fishermen, give the average hours fished by each person up to the time of the census interview. These fig- ures for average hours per person varied from 3 .2 in the winter of 1944-45 and 3 .4 in the winter of 1945-46 to 3.7 in the summer of 1945 and 3.9 in the summer of 1944. Probably the average fisherman stays out longer in the summer than in the winter because of the longer hours of day- light and the more easily tolerated weather. Also, the figures given may have been influenced by the fact that in the su.nmer the interview co- incided more often with the end of the fishermen's activity for the day. In the winter the interview often was performed on the ice while the fisher- man was still active. The fishing success ratio, expressed either in fish per person (per "fisherman trip") or in fish per person-hour, ran almost identical- ly for the two winter seasons and the summer season of 1945, but was appreciably higher in the summer of 1944 (table 1). However, the fig- ures for the summer of 1944 are for a restricted area. The figures regarding the fishing success will be discussed in much more detail below . An average catch of around 2 fish per person (per fishing trip) does not make a very showy stringerful. Of course, a certain number of fishermen went home with a respectable catch and occasionally (though very seldom) a "limit" catch of one or more species was recorded. On the other hand, many persons fished a stint of several hours without catching a single fish. For example, in the winter of 1944-45, 37 percent of the total number of fishermen interviewed had caught no fish; 56 percent had caugjit 1 to 5; 5 percent had caught 5 to 10 each; and only 2 per- cent had taken more than 10 fish apiece . The corresponding calculations for the other 3 sea- sons have not been made but it is probable that the figures would run somewhat similar. This percentage of empty creels is about the same as is to be found in some other areas, as shown by the published literature on creel census. Residence and distance travelled. For the win- ter of 1944-45, an analysis has been made of the places of residence of the fishermen and the dis- tances travelled to the fishing grounds. As shown in table 2, fishermen residing in at least 120 different places fished in the area under ob- servation at some time during the winter . Lake Pepin alone (pool 4-=L) was visited by fishermen from 52 separate addresses. However, all of the addresses given dur- ing the winter 1944-45 were in the 3 states: Tatle 1,- - General statisticsi four seasons of creel census. ISumber of Cards 1^1111113 er of Men number of Women HuralDer of Fishermen Per cent Men Per cent Women Pishermen per Card Person-hours Ave, Hours per Person Total Fish Fish per Person Fish per Person-hour Summer 19A4 i^Z 755 879 865^ 1>4 1.8 3^30 3.9 21^1 2.8 0.71 Winter 19Z44-i+5 3^10 7h83 393 7876 I 955^ I 5^ i i 2.3 : 2559^ ' 3.2 13827 1.8 0.5^ Summer Winter 194'5 I 19^5-^ 13880 19^+52 3959 23/Hl 835S 17?S 1.7 85699 3.7 if 3093 1.8 0.50 I 2563 i 5^38 : 283 j 5721 i 95^ I 3^ 2.2 19555 8928 1.6 0.46 Table 2,- -Residence of fishermen, vdnter 19^-^5. Fisli in Pool Places Eepresented ij-R ^ iJ-L 52 5 15 5A. 21 6 & 7 18 8 & 9 9 10 13 Total - Less Daxilicates 120 Wisconsin, Minnesota, and Iowa, bordering on the Mississippi River in this area. By contrast, in the summer fishing there was a significant number of addresses given from other states, such as Illinois. About 10 percent of the fishermen in the winter of 1944-45 were classed as "local" in re- gard to the place where they were fishing (within walking distance), and another 36 percent came from distances of 1 to 5 miles (table 3). How- ever, many fishermen drove considerable distances to fish. The average (one-way) dis- tance travelled was approximately 11 miles. This means that allowing 2 fishermen per auto- mobile the 7,900 interviewed fishermen drove a total of approximately 85,000 miles. Catch composition Species composition of all-over catch. Table 4 shows the species composition of the entire catch recorded for each of the 4 creel census seasons . As explained in the footnotes to table 4 the crappie were not differentiated as to species; the bullheads included 3 separate species; the black bass were not separated as to largemouth and smallmouth; a few yellow bass (Morone interrupta) were recorded with the white bass; and the "all other" classification included a variety of species . The figures given include only legal- sized fish (at the time of this study there were size limits on most of the species of fish) . The fishermen were questioned regarding their catch of under-sized fish; but it is probable that the figures obtained are not reliable, hence no at- tempt has been made to analyze and tabulate them. In general, however, the numbers of undersized fish taken were not particularly large . In both the summer and winter fishing the all-over catch was dominated by bluegill and crappie with the various other species following in numbers . Two species of catfish and the 3 species of bullheads appeared in substantial numbers in the summer fishing but were not taken in the winter. Likewise, the drum ap- peared only in the summer catch . In the winter of 1944-45 a considerable number of shovelnose sturgeon were taken by fishing in the open water below the Dresbach Dam (pool 8). The data of table 4 are recapitulated in table 5 (in a some- what condensed manner), in the form of percentages of the total. The bluegill -crappie combination made up close to or better than 50 percent of the total in each of the 4 seasons . Composition by seasons, pools, and localities. Table 5 shows some of the contrast between the summer and winter fishing. Whereas in the summer the percentage of sauger was less than that of walleye, and was only a small part of the total catch, in each of the two winters the per- centage of sauger was much larger than that of walleye. Casual observation in the period 1946- 50 indicated that the catch of sauger s had in- creased greatly in proportion both to the catch of waUeye and to the total catch, and in both the summer and winter fishing. Possibly a few con- secutive abundant year -classes of sauger entered the fishery in that period. The varying proportions of bluegill to crappie (table 5) are perhaps due not so much to a difference between the winter and summer fishing as to the fact that the 4 different censuses were of different territorial extent; some of them included a larger proportion of bluegill - producing water . The percentage of the total catch repre- sented by northern pike is a small figure (1 to 4 percent). However, considering the size of this species of fish, its importance to the fishery is greater than the figures indicate. Much the same holds true for the black bass catch. Par- ticularly in some localities, catfish and drum are important constituents of the fishery. The season -to -season changes in the species makeup of the catch for certain selected parts of the river are shown in tables 6 to 8. Table 6 gives the percentage composition of the catch in pool 8 for the 4 seasons. The 2 sum- mers run fairly well parallel as do the 2 winters. The catch of crappie in proportion to that of blue- gill was somewhat higher in the winter than in the summer; and the combined catch of the two ran higher in percentage in the winter because the winter catch was restricted to fewer kinds of fish. Sauger in proportion to walleye ran higher 10 Table 3. —la. stance trarelled to fish, winter l$kii-k5. Distance, Miles Per cent of Total Local j 10 1-5 1 36 6-10 17 11-20 17 21 - /JO 18 Over kO 2 Average a n miles 11 Talile >^, — Species composition of catch, four seasons. Kuri'bers of fish, recorded. Summer Summer 1 Winter Winter 19ijij- 19^5 1944-45 1945-46 Blaegill 712 1591^ 2639 309^)- Crappie •'•' 956 7834 5849 1141 Walleye 198 4098 1756 1102 Satiger 51 1007 2456 2761 Northern Pike 80 1258 ^5 113 Chajmel Catfish 255 2^1 Flathead Catfish Ik i+66 Bullhead ^) 50 1532 3 Black Bass ^' 61 2if59 308 563 \irhite Bass ^^ 31 2116 33 90 Drum 25 24-38 Carp 3 802 1 Yellow Perch 30B 36 36 All other ^^ 5 170 251 28 Total 2¥ll 43093 13827 8928 1) Both "black crappie and v:hite crappie. 2) Three species. 3) Both largemouth and smallmouth. 4) Includes a small numher of yellovf "bass. 5) In winter 1944-45, includes 242 sand sturgeon. Pool 8. In summer, includes hovrfin, gar, eel, mooneye, etc. 12 Table 5. --Percentage species composition. Species 1/ Svunmer 19^ Siiimner \9hr5 1 Winter 19i4iM|.5 Winter 19/),5_46 Blaegill 29 37 19 i ( 35 Grapple 39 18 lt.2 13 Walleye 8 10 13 12 Sauger 2 2 18 31 northern Pike 3 3 h 1 Catfish y 11 7 Bullhead 2 h Black Bass 2 6 2 6 All other 3 1^ a 2 Total 59 101 100 100 1/ "ee notes for tabic h, 2/ .^oth channel and flathead catfish. 13 TaT)le 6,"- - Percentage species composition, Pool 8. Species 2/ Bluegill Crappie Walleye Sanger Northern Pike Catfish All other Summer 19^*4 shimmer 1945 Winter 19/14-45 Winter 1945-46 30 16 : 25 3^^ 36 28 51 43 9 12 t 4 5 3 6 9 14 4 11 2 2 12 15 i j 5 12 8 1 TV See notes for tables U and 5. 14 Table 7. "Percentage species composition, Pool ^L , y Species Bluegill Grapple walleye Saucer JTorthem Pike Catfish All other 1/ See notes for tables U and 5. Sujnmer 19^4-5 Winter 19/ji4-li5 Winter 191^5-2+6 2 i i 2 1 1 i 1 56 \ i 39 ■ 28 6 60 70 h 1 1 1 29 1 15 TaTsle 8.- -Percentage species composition. Pool 10, y Species Bluegill Crappie Walleye Sanger Northern Pike Catfish All other ^ Svunmer 19^5 Winter 19MH45 Winter 58 ; i 1^ 68 12 5 13 1 2 i 1 1 \ 1 8 20 19 18 1/ See notes for tables U and 5. 2/ Largely "black hass in the winter; largely "black "bass and white "bass in the summer. See text. 16 in the winter than in the summer; and the per- centage of northern pike dropped in the winter . Table 7 shows that for pool 4-L (Lake Pepin) both the summer and winter catch ran largely to walleye and sauger. Here also the proportion of sauger to walleye was much great- er in the winter, being about 2: 1 in favor of sauger in the winter catch, and 1:9 in the sum- mer catch (1945). The substantial percentage in the "all other" classification in the summer fishery (29 percent) was heavily contributed to by the catch of carp. The catch of pool 10 (table 8) showed relatively much less fluctuation from summer to winter. In both the summer and winter seasons, well over half of the total catch was bluegill . This reflects the presence of a remarkable blue- gill fishery at one particular locality (Winter Creek), which will be discussed in more detail below. Walleye made up a very small part of the catch and the number of sauger was almost zero. In the "all other" category was included a substantial number of black bass . Here again a single locality (in this instance Gremore Lake) was the principal factor. In this lake black bass (largemouth) are caught in goodly numbers in the winter as well as in the summer fishing. This is unusual, there being only a few other localities in the river where black bass are taken by ice fishing. Tables 9 and 10 give the species percent- age composition of the catch by pools for the summer of 1945 and the winter of 1944-45. (The census of the summer of 1944 involved only pool 8 and part of pool 7; and the census of the winter of 1945-46 included only pools 4-L, 8, and 10, the figures for which may be obtained from tables 6 to 8.) In the summer fishery, bluegill and crap- pie were important species in all of the pools except pool 4 -R and pool 4-L. There was, how- ever, considerable variation in the percentage numbers of these two species from pool to pool. Walleye and sauger proved to be the dominant species for pools 4-R and 4-L but were far below the numbers of bluegill and crappie in the re- mainder of the pools . Northern pike loomed relatively large in pools 5A to 8; catfish appeared in good numbers in pools 8 to 11; and bullhead came into its own in pool 9 where a heavy local concentration of bullhead caused it to dominate the entire catch. Various other species also showed considerable variation from pool to pool. In the winter catch (1944-45), as shown in table 10, the bluegill -crappie combination led all other species combined in all pools except pool 4-L (Lake Pepin). Within this combination, however, there was considerable variation in percentage. For instance, pools 4-R, 5A, and 7 produced several times as many crappie as bluegill, while in pool 10, as mentioned above, the winter catch ran very heavily to bluegill . The winter catch of walleye and sauger was al- most inconsequential for all of the pools except 4-R and 4-L. Northern pike showed up in their greatest percentage numbers in pools 4-R and 6; and black bass entered the winter fishery in sub- stantial numbers only in pool 10. Table 11 gives the species composition of the catch (by percentages) for several im - portant localities in the summer of 1945. The localities are grouped in this table according to the species, or species combinations, which dominate the catch . In the localities in Group I the catch was made up largely of the bluegill - crappie combination; the localities of Group II had a catch made up mostly of walleye and sauger; in Group III the catch was mostly of species other than bluegill, crappie, walleye, and sauger; and in Group IV the catch was of mixed species with no clear dominance . Thus, although several general areas tended toward production of a specialized catch (such as walleye and sauger in Lake Pepin), other general areas such as pool 8 and pool 10 offered several kinds of fishing with- in the area, and varied from one locality to another. Thus in pool 8, Black River produced mostly crappie and bluegill, while Dresbach Dam had a mixed catch; and in pool 10 several local- ities were of the bluegill -crappie category, and others, such as the "Pool above the Dam", pro- duced catfish or other species. An even greater degree of segregation of localities by catch composition was shown in the winter fishing (1944-45), as listed in table 12. The localities in Lake Pepin (Group C) produced almost no other kinds of fish besides walleye and sauger. Many localities furnished specialized fishing for blue- 17 T'alile 9.-- Percentage species coriposition, summer 19'+5. Species -^ i<-E i|-L 5Ai i Pool 6 7 8 9 10 11 Total (All Pools) Blaeeill 6 2 33 55 37 16 23 58 12 37 Crappie 2 2 21 15 13 28 7 12 UO 18 Walleye 31 56 15 16 17 12 7 1 7 10 Saucer 6 6 6 1 5 2 ITorthem Pike 2 i^ 18 7 9 11 2 1 3 Catfish 5 1 3 1 h 15 5 8 9 7 Bullhead 7 1 h 5 37 1 1 it Black Bass 2+ 9 i^ 3 15 1 2 9 2 6 White Bass 3 8 6 1 1 2 8 i^ 5 Drum 9 2 3 9 1 19 6 All other H 26 10 2 5 1 1 3 1/ See notes for tables li and 5. 2! Donirited, in pool=: U-Ii anH li-L, by carp, 18 Tatle 10.- -Percentage species composition, vdnter 19^44-^5 • Species 1/ k-H il-L Pool 5k 6 7 8 10 Total (All Pools) Bluegill l^ 2 33 8 25 7h 19 Crappie 62 1 95 55 89 51 5 1^2 Walleye 13 ' 39 3 k 2 13 Sauger 9 60 9 18 Northern Pike 12 1 1 11 2 k Black "Ras s 17 2 All other 2/ 1 1 8 2 2 y See notes for tables \x and 5. ^ Dominated, in pool 8, by sand sturgeon. 19 Ta"ble 11.- -Percentage species conroosition, certain localities, smnmer 19^5. Per cent of Catch Group ' Pool Ho. Locality Bluegill & Crappie Walleye & Sauger All Others Dominant Species I 5 Minneiska 75 2 23 Bluegill 6 Bathhouse Slough 90 2 8 Bluegill 6 Bartlett lia.ke 77 23 Bluegill 8 Black River 81 h 15 Bluegill & Crappie 10 Amtro Park 80 1 19 Bluegill 10 Sand Pit 92 8 Bluegill & Crappie 10 Grenore T^ike 80 1 19 Bluegill 10 E. R. Bridge 77 3 20 Bluegill 10 Winter Creek 90 2 8 Bluegill 11 Swift Slough 87 13 Crappie II 4-R Red Wing Dam 6 76 16 Walleye ij-L Upper Lake Pepin 97 3 Walleye 6 T>i,Tii 5A i^ 85 11 Walleye 7 Treinpea.leau Dam 2 95 3 Walleye III i(-E Red Wing Levee 11 89 Carp 9 Crooked Creek 30 70 Bullhead 10 Pool ahove Dam 5 95 Chan. Catfish IV 5A V/hitman Dan 18 36 46 - 8 DreslDach Dam 27 3^ 39 - 9 Genoa Dam 21 22 57 - 11 Tv/'elvo-Mile Slough kz 8 50 - 11 Guttenljerg Dam 21 31 i»8 _ 1) In Group I, more than 70?^ of total is "hluegill plus cra-oTiic". In Group II, more than 70^ of total is "^ra-lleye plus sauger". In Grouia III, more than 70^ is "bther than ■bluegill, crappie, vrailleye, and sauger". In Grout) IV, less than 6o^ of total is any one of aTiove (VLtap-nr-lpn. Ls any one of ahove categories. 20 Tatle 12, --Percentage species composition, certain localities, winter 19i»^WJ-5. Per cent of Catch Group A B 1) D >00l No. Locality Bluegill ' ! Crappie Walleye & Sauger All Other 6 Bart let t Lake 70 1 29 10 Winter Creek 100 k-B. Beef Slough 2 75 23 ij-R Goose Lake 12 85 2 1 5A Fountain City Bay 2 95 3 6 Straight Slwigh 8 91 1 7 Trempealeaa Spillway k 93 3 8 French Lake 97 2 1 8 Bank Slough 7 83 10 l^L King's Coulee 100 k-L Lake City 97 3 /<-L Lacupolis 99 1 l^L Central Point 100 i|-R Red Wing Dam 33 60 7 8 Slough "22 « 40 >58 1 1 10 Gremore Lake ^ 23 16 61 1) In Group A, more than 70^5 of total is "bluegill". In Group B, more than 70^5 of total is "crappie". In Group C, more than 705^ of total is "walleye plus sauger". In Group D, less than 65^, of total is any one of ahove categories, or "all other", 2) In Gremore Lake, 55^ of total is hlack "bass. 21 gill; in particular, the fishery of Winter Creek consisted entirely of this species. Table 13 gives the same kind of informa- tion for some of the localities for the winter fishing, 1945-46. Here again the various local- ities showed a tendency toward a more special- ized fishery than in the summer fishing. Several abrupt shifts are to be noted. For instance, French Lake produced almost nothing but crappie in 1944-45, but showed up as a bluegill water in 1945-46. On the other hand, Slough "22 " produced more crappie in proportion to bluegill in 1945-46 than it did in 1944-45. Changes such as these likely are due to changes in the method of attack. A few good catches of bluegill at the beginning of the winter may in- still the idea in the fishermen's minds that good bluegill fishing is to be had in that particular water; and the fishermen in that locality will use worms rather than minnows for bait throughout the remainder of the season; and hence the sea- son's catch will be predominantly bluegill rather than crappie . Presumably then, the species make-up of the catch, especially in the winter fishing, is a product of the species abundance in a given locality and the type of fishing (i.e., kind of bait) employed. However, in some areas there actually is a comparative scarcity of some kinds of fish. For instance, in Lake Pepin the game fish population runs largely to walleye and sauger; and comparatively few bluegills would be caught even if worms were used for bait. The fishermen through years of experience are fairly well aware of these catch potentialities of the various waters and use fishing methods which are most likely to produce results. Fishing success Definition and terms. All discussion of fishing success in this report is in terms of number of fish caught per fisherman-hour of fishing, ex- pressed as decimal fractions. They are averages obtained by dividing a sum of fish by a sum of fisherman -hour s . These figures for fishing success are stated in terms of the total catch of all species regardless of the number of species involved or the predominance of any one or more species. This procedure is necessary since there is no way of breaking down the field data into the amount of fishing effort expended toward the capture of the separate species. In a way, this produces some inequitable and misleading figures. As measured by return in the thrill of capture or in meat for the table, one fish does not always equal another. A 3 -pound bass puts up a better fight than a 2 -ounce bluegill; and a 35 -inch northern pike furnishes more eating than a 10- inch bullhead. However, it must be borne in mind that a good share of the fishing here re- ported produced a mixed catch, or one running mostly to panfish (bluegill and crappie) . There- fore, it is the exceptional rather than the average catch which is composed of unusually large and desirable fish, or of unusually small and undesirable fish. Therefore, the simple ex- pression of fish per hour can be used with a great deal of justification for making various estimates and comparisons of fishing success. Success by seasons. Table 14 presents a sum- mary of the total numbers of fish caught, the person-hours of fishing, and the average fish per hour, for each of the 4 seasons, pool by pool. The figures for fishing success (average fish per hour) are recapitulated in table 15. The all-over totals were 0.71 fish per hour for the summer of 1944; 0.50 for the sum- mer of 1945; 0.54 for the winter of 1944-45; and 0.46 for the winter of 1945-46. Although these figures give a rough indication of the general fishing success for these 4 seasons, they are not strictly comparable since each average covers a different combination of pools and localities. The seasonal averages for individual pools varied from 0.24 fish per hour for pool 4-L in the sum- mer of 1945, to 1.10 fish per hour for pool 10 in the winter of 1945-46. Only for one pool for one season was a seasonal average of more than one fish per hour produced; about half of all the in- dividual seasonal averages by pools ran less than 0.50 fish per hour. Success by localities. The average fishing suc- cess by seasons for several selected localities is given in table 16. These figures are of the same general order as the corresponding figures 22 Table I3,- -Percentage species composition, certain localities, winter 19^5-^6. Per cent of Catch Group ^' Pool No. Locality Bluegill Crappie Walleye & Saucer All Others A 8 French Lake 86 11 3 1 10 V/inter Creek 99 1 B 8 Slovigh "22" 10 81^ 3 3 8 Bank Slouch 3 95 2 C ij-L Take City 98 2 M-L Lacupolis 97 3 4-L Central Point 100 i4-L Frontenac Point 99 1 D 10 G-remore Lake ^^ 39 2 59 1) See footnote 1), tahle 12, 2) In G-remore Lake, ^Q]l> of total is "black "bass. 23 o EH H O f-) 3- ^ • CM ('^o CM CJs^ 00 ^J^ • cnvr\ o H CM CJ\ d^ vri 0<0 » -^ CO CO VPi^ CM v^^^ CO OS O ^ H O H CN^ Os OS O Hvnvo rH CM O C^CM CJN CD OS O r-l rH ^ Cvl O Iv-3- . m n o s u i «H u o o o P) /3 n (0 0) o o w •ri CO •H H OS CO H W^ CO CM CM cno C^ Os C^ • H CM O r^oo q\ O CM so \r\cs- so o in o vrv 3 C^ CM en CM CM en o m en CM it ^ cnso . cncs- o so ^ CM H H v^ cr\ c^ • H cno Cs-^ CM CM r-4 ^ H H • CM u^. O CM a-M3 CM OS • cn3- o HsO . enoo o so vn en OS ^n cjN P-oo • o CO 4:^ CM 3; CM OS ^ • cno Qs^ 00 cno en HO. H eno cs-r- o en en 3- CM H • enco o H ^ OS CO C^CM O C^ • H eno Hso en vnvn^ -:J- O . H O incjs-^ C^ OsCM r- en . H C-- O vn ency* so CO CM CM 00 • CM IN- O COSO H 2f M~\\n w^ o ♦ H eno ^ so r-co o vncM so o . en mo H EH en CM Q CM so u o M ■p o cd CTs S f^ H g U u s a 9 m 3 ta 03 ^ 1 ^ u Xi 3 o 5^ -a ;J 0) i-S 5 ,H Osri o ^ OS -H O H CJS tH W (i( H fi. W Fh HPh W Pq H Ph •p g ^ CO O t1 Table 15. --Fishing success, fish per hour, for four seasons. Pool 4-R 4.-L 5 5A 6 7 8 9 10 11 Total - All Pools Season Summer 19¥»- Summer 19^5 Winter 19^14-45 ¥inter 19^+5-^ 0.69 0.72 0.71 0.29 0.24 0.43 0.29 OM 0.26 0.37 0.42 0.95 0.47 0.50 0.52 0.43 0.59 0.38 0.93 0.65 0.64 0.54 0.28 0.51 1.10 o,h6 25 Table 16, --Fishing success, fish -per hour, for certain localities. Season Pool Locality Summer 19^ Summer 19^5 Winter 19iji(_i4.5 Winter 19i^5_Z^ l^R Red ¥ing Dam 0.30 O.iJO li-L Lacupoli s 0.25 0.50 0.22 Ij-L Lake City 0.20 Q,hQ 0.32 4-L StocKholm 0.30 0.2i|- k--L Central Point 0.66 0.51 i(~L Front enac Point 0.41 0.27 ij-L Madsen Point 0.27 0.18 5A Fountain City Bay 0.28 0.60 6 Bartlett Tflke 0.65 0.38 8 DreslDach TVim 0,k3 O.iK) 0.80 O.LiS 8 Black River 0.83 0.60 8 French Lake 0.2ij- 0.87 8 Slou^-h "22" 0.73 0.51 8 Ba.nk Slough 0.55 0.30 10 Gremore Lake 1.02 0.2U o.i^3 10 Winter Creek 0.87 3.01 i)-.6o 26 for the pools. There is one notable exception, however, Winter Creek, which is near Prairie du Chien in pool IQ produced fishing in each of the two winters which averaged from 3- to 10 times better than the fishing at the various other local- ities. This probably was due to an underground spring, which keeps a fair sized area free from ice throughout the winter. Apparently the blue- gills are attracted to and induced to feed in this open water area and hence are easily caught. Table 17 gives the total numbers of separate localities which were censused in each of the 4 seasons. These numbers are substan- tial, especially for the summer of 1945 and the winter of 1944-45. Many of the tabulated "localities" were of minor significance in their contributions to general averages, since for many of them less than 100 or 200 fisherman -hours were recorded for an entire season. The com- plete list of locality names is not given in this report . In table 17 is listed the numbers of local- ities, for each of the seasons, with a total of more than 300 hours fishing per locality per season. Fishing success for the localities is given in terms of the range and the mean. The ranges were broad and the deviations large, as shown by the fact that V (= \QOS/ M) runs as high as 44 for the winter of 1944-45, and 76 for the summer of 1945. These figures are given in terms of total fish per hour, regardless of kinds and sizes of fish. Some of the qualitative aspects (species composition of the catch) for certain of the local- ities have been discussed above. Variation throughout the season. Day-to-day fluctuations in the average fishing success (total, all pools) for the summer 1945 are shown in figure 1. As explained above, each field worker usually found it impossible to cover his territory completely on any given day . Therefore, his returns for successive days often represented separate localities or portions of his territory. This factor probably influenced the apparent daily averages for the total area, causing them to vary from day to day more than would have been the case had it been possible to cover all localities every day. The daily averages for the entire season (total all pools) showed a range of from 0.20 to 1.23 fish per hour, with a mean of 0.54 and a standard deviation of 0.21 . This gives a fairly high coefficient of variation, V = 39. To alleviate this effect of daily fluctuation, the graph of figure 1 is constructed with moving averages of fives. Even so, the line still has a jagged appearance. It is difficult to say just how much of this fluctuation from one day to the next is real and how much is due to the circumstance explained above. Hansen (1942) found that for Lake Chautanqua, the periods of good fishing tended to be short, with ateep-sided curves. In three Indian lakes, as reported by Ricker (1945), the week-to-week variations throughout the sum- mer were very irregular, and were different for different species. Some of the variations cover- ing a week or more probably are authentic and are tied in with physical factors, although these may be but vaguely evident . In general, the fishing success ratio from about mid-July on was higher and also subject to more fluctuation than it had been during the early part of the summer . This holds true for most of the entire area, but comes about especially be- cause of the pronounced tendency in this direction of the more down-river parts of the area (i.e., pool 10 and pool 11). This is brought out in figure 2, which shows comparative graphs for pool 4L, pool 10, and the total (all pools) . In this figure, weekly rather than daily averages are used, of necessity, since for any given pool the effect of working various days is consider- able . During any given week, however, an entire pool was fairly well covered. The graph for pool 10 follows closely the contours of the graph for the total (all pools) . The existence of a definite mathematical correla- tionship will be pointed out below . On the other hand, the line for pool 4-L is much more steady and level, showing only a minor peak during the mid-July period. These two pools, being some distance apart and very different physiographic - ally, were subject to different sets of physical conditions throughout the season. Furthermore, the fisheries of the 2 pools were of different natures, the catch of pool 4-L being mostly wall- eye and sauger, while that in pool 10 ran largely to bluegill, crappie, and bass . This difference 27 Talile 17." "Fishing success, four seasons, vrith ranges and means of week-to-week values. Season ITumter of Localities Used in . Sam-oled This Tahle"'-^ Fisli per hour ■Range' 2) Mean. Sumner 19^14 17 5 O.iJ-3-0.83 - - - Winter 19¥j-if5 51 20 0.2iK.1.05 0.52 0.23 /44 Summer 19^5 71 6o 0.08-2.0it. 0.^ 0.37 76 Winter lSk5-k6 17 13 0.18-0.87 0.37 « « 1) Only localities with total person-hours more tlian 3OO. 2) Omitting "Winter Creek", which vras 3. 01 fish/hour in v/inter 19¥l-i+5, and 4.6o in vriLnter 19iJ-5-i4'6. 28 -anov^ / MSi^ 0 o in 6 0 (0 _ *J - a> ani u'" (VI _ ff» - « >i- (0 _ ^ _ o o o p. M ly O - z +> z 1 3in - < i5 o kl rH «(a ^ M o J ? W III !3 «vi :l ■-I ^ -a- o ^ H O 4; »r>oH/"«'^ 8 z. CO a U S3 CO 4h ^ fr H 2 1 Z ITS , z J- Im^ 1 J- ON £ H o i U} u • W Ul 0) -3 y CO m (U o o d :3 wO;s M Qrt)'^ Si 1 s • J- s . a i^vgb CO ll Therefore, a comparison has been made of the seasonal averages for 11 localities, each of which was sampled in both winters. These 11 localities are the ones listed for both winters in table 16, except for the omission of Winter Creek. This comparison yields the following figures: the mean for 1944-45 is 0.46; the mean for 1945-46 is 0.39 fish per hour. The value of d/rfj is 0.9. This is not of statistical signific- ance; and hence it cannot be proved mathematic- ally that the fishing in these localities was better in one of the two winters than in the other . The week-to-week averages for fishing success for pool 8 in the summers 1944 and 1945 are shown in figure 6. The individual weekly fluctuations in these two curves are large. The over -all averages for fishing success for the two summer censuses are 0.71 fish per hour for 1944 and 0.50 for 1945. However, since the territory involved was of much greater ex- tent in 1945, the difference between the two mean values has little meaning. From only 3 localities were adequate samples taken in both summers (Dresbach Dam, Onalaska Spillway, and Black River, all in pool 8). The over -all seasonal mean for the total of these 3 localities was 0.63 fish per hour in 1944 and 0.41 in 1945. A comparison of these two means by the method of comparing small samples yields a value of ^ equal to 1.5 (for which P is somewhat larger than 0.1). The statistical significance therefore is doubtful and it cannot be considered as proven that the fishing in this section of the Mississippi River was better in the summer of 1944 than 1945. Influence of certain factors Fishing pressure. Several authors have attempt- ed to show a relationship of the fishing success with the intensity of fishing. Eschmeyer (1942) stated that in Norris Reservoir, Tennessee, the fishing intensity increased for several consecu- tive seasons without any appreciable decline in catch per hour . In other words, the total take increased. However, in another water (Fife Lake, Michigan), the same author (Eschmeyer, 1939) found the catch per hour to decline through 4 seasons, as the fishing intensity increased. Thus he reasoned that the lake, which was fairly heavily fished, had about a constant available crop from one year to the next. On the Upper Mississippi River, on the whole it is probable that the fishing pressure has little or no influence upon the catch. The available crop remains large in relation to the annual harvest. At certain places and times, however, the fishing intensity may have a tempor- ary effect. Especially is this true of certain fishing spots where the fishing is concentrated at the beginning of winter . An area of only a few acres may be worked by scores of fisher- men day after day if the fish happen to be biting well. In the winter the fish are not moving so much as in the summer, presumably; and what was the catchable population of a small slough or backwater at the onset of ice cover may be- come fished out in a few days or weeks, result- ing in poorer fishing for the remainder of the winter. Eschmeyer (1942) believgd that the de- cline in the fishing success in Norris Reservoir, after June may have been due largely to the re- moval of large numbers of fish early in the season. Also in Fife Lake, the same author (Eschmeyer, 1939) attributed the poor fishing in the late summer partly to the early-summer re- moval of a considerable proportion of the avail- able crop of fish; the remainder found food more available . Bait. Table 19 shows the fishing success for each of the 4 seasons according to the type of bait used. There is of necessity some lumping of data in this table. For instance, quite common- ly a fisherman or a fishing party used both worms and minnows on the same day, and in these cases no attempt was made in the censusing to list separately the amount of fishing effort and number of fish caught for each of the two types of bait. Therefore, a category had to be set up labeled "worms and minnows" . Also, the classification "other natural bait" lumps a wide variety (liter- ally dozens of kinds) of baits, ranging from frogs to doug^ -halls. Because of the relatively small amount of fishing done with any one type of artificial bait, such as plugs, spinners, flies, etc . , all of these are placed together in one category . 35 Tatle 19. --Fishing success, fish per hour, "by type of bait. Season Worms Minnows Svunmer 194J^ O.96 O.63 Summer 19'<-5 O.69 0,33 Winter 19^*4-45 1,21 0.49 Winter 19k5-k6 3.26 0,31 Worms and Minnows 0,63 0.50 0.76 Other Natural Baits 0.52 Artificial Total Baits J. ^ VCX^ - 0.71 0.29 0.50 - 0,54 _ oM 36 Practically all of the winter fishing was done with worms and minnows to the exclusion of all other types of bait. Except as to bait, no other attempt has been made to classify the various techniques of fishing, i.e., as to kind of tackle or the manner of its use. Also, no dis- tinction has been made between shore fishing and fishing from a boat, or between ice fishing and fishing in the open water in the winter (some open water fishing was done, particularly below dams, but it did not amount to a very large per- centage of the whole) . In general, worms produced definitely more fish per hour than did minnows. This was true particularly for the winter of 1945-46, the figures for which were influenced greatly by the very large numbers of bluegills caught on worms at Winter Creek. The figures for artificial baits, and natural baits other than worms or minnows, probably are not very reliable since the amount of fishing involved was not large. The figures, such as they are, show that for the summer of 1945 these types of bait were not as productive in fish per hour as worms and compared not too favorably with tlie success obtained by using minnows. In these comparisons it must be remem- bered that the quality of the catch, both as to species and size, varied greatly with the type of bait used. Worms produced mostly bluegills; the larger fish, such as crappie and walleyes, were caught with minnows . Time of day. The influence of the time of day at which the fishing was done, upon the fishing success, is shown in table 20 . There is of necessity some lumping of information because of the form in which the field data were recorded. For instance, if a fishing party fished throughout the entire day or a large part of it, the census card was made to read "morning and afternoon", "afternoon and evening", or "morning, afternoon, and evening", as the case might be. With minor disparity, the figures of table 20 show that in both the winter and summer fishing the catch rate was higher in the early and late parts of the day than it was during the mid- day. To some extent, the morning fishing was the best of all. These conclusions agree well with the general opinion among fishermen, most of whom have heard, or read, or concluded that fishing slacks off in the middle of the day. Despite this belief, however, the daytime fishing intensity is greater than that in the early morn- ing or in the evening; apparently only the inveter- ate fishermen are willing to start fishing early or stay out late . Eschmeyer (1935) found much the same situation. Fishing was best at about daybreak and about dusk, although the heaviest fishing load was in the mid-morning and late afternoon. However, Pelton (1950) reported that in Lake Alma, Ohio, "daytime fishing (8 a .m . to 5 p.m.) was nearly twice as good as night fishing." Sex of fishermen. The numbers of male and female fishermen were recorded on the field forms but part of the data cannot be separated. That is, many cards recorded the fishing of a fishing party containing both men and women without any indication as to what part of the catch was caught by the members of either sex. In the summer fishing for 1944, field cards showing men alone averaged 0. 78 fish per hour, while cards with both men and women had an average fishing success of 0 .55 (there are too few cards for women alone to justify computing an average) . In the winter fishing (1944-45), men alone caught 0 . 57 fish per hour, parties composed of both men and women caught 0.38, and women alone caught 0.35. The evidence thus is that the men definitely were better fishermen than the women. Water temperature . There is no doubt that water temperature can and often does exert a considerable influence upon the feeding habits of fish and therefore upon their catchability . How- ever, this influence is apt to be modified or obscured by many other factors so that it is not always plainly evident . Furthermore, in attempt- ing to set up any figures which will demonstrate the relationship of water temperature to fishing success, difficulty is experienced in determining just what measurements should be made and what information should be recorded. For instance, it is not always certain at what water depth the temperature measurement should be made, par- ticularly in a water which is sharply stratified thermally, since fish move freely from one depth to another and are caught at various depths. 37 Taljle 20."-rishing saccess, fish, per hour, "by time of day. Season Morning Morning and Afternoon Evening Total Afternoon Summer 19M«' 0.81 0.53 0.71 O.Bo 0.71 Summer 191^5 0.52 0.58 0.i^5 O.hS 0.50 Winter 1944-i^5 0.75 0.ii4 0.52 0.70 , 0.5^ Winter 19'^^k6 , 0.7^ 0.30 0.k6 _ ' oM 38 Furthermore, when a large area is under con- sideration, water temperature from one place to another may vary considerably. Surface temper- atures are under the influence of atmospheric conditions and may change from time to time throughout a given period. Probably for these reasons few authors have attempted to demon- strate correlations between water temperature and recorded catch . In the summer of 1945, water tempera- ture was recorded somewhat irregularly at several places, all in pool 10. The most com- plete of these sets of data is that for the locality "Railroad Bridge" at Prairie du Chien. Here the water temperature was measured almost every day from about June 10 to the end of August. These figures are averaged week by week and are presented in table 21 . To a reasonable ex- tent, these readings may be used as representa- tive of the water temperature changes throughout most of the entire area. It has been observed during the course of other work on this portion of the river that water temperatures in the various pools, and localities within pools, follow each other closely, at least when the average of a period of several days is considered. Almost everywhere the water is relatively shallow, is subject to some current, and hence is well mixed. There virtually is no vertical stratification and comparatively little prolonged stagnation. TTie effect of sudden changes in air temperature upon the water surface temperature is largely nullified by the current and wind and wave action . The locality in question (Railroad Bridge) is near to or actually a part of the main flow of the river and hence produces a fairly representative temperature sample. Table 21 records the weekly fishing suc- cess averages for pool 10 and for the total (all pools) . As shown by the table, there exists a mathematical correlation between these two sets of averages and the recorded water temperature with a reasonably high degree of statistical sig- nificance. Whether this correlation is actually causal or is mostly coincidental may be open to question since there are many other factors which might enter the picture. If the relation- ship of catch to water temperature, as shown here, is a real one, the import is that within the temperature range here recorded, the higher the temperature the better the fishing. The findings of Dendy (1946), and of Eschmeyer, Manges, and HasLbauer (1946) are to the same effect; i.e., that within a certain range and under a certain combination of circumstances, higher water temperatures favor fishing. However, it has been held by many that extremely warm water may be the cause of the mid-summer slump in fishing which sometimes occurs (perhaps in- directly, by increasing the supply of available food, through the hatching of insects) . Most of the localities, particularly such ones as Lake Pepin, did not show a mathematical correlation of fishing success with water temper- ature. Changes in water levels. The moving, feeding, and biting of most of the species of fish in the river are influenced to a certain extent both by the water level and by changes in level (rising and falling) . This is the firm belief of most of the sport fishermen and is based upon their ob- servations . Information based on measurement, such as the daily readings of water level gauges, is difficult to apply to the changes of a large and varied sport fishery. For instance, during the summer of 1945 the hydrographs for the various river stations (constructed from gauge readings) showed a different pattern for the water levels of the different pools, or even sections within pools. Thus it is almost meaningless to attempt to fix upon any mathematical correlations between water levels (or level changes) and fishing suc- cess. Throughout the entire area there was a general trend from relatively high and fluctuat - ing water levels (flood waters) at the beginning of the summer fishing season, to lower and more stabilized levels (normal pool levels) through the latter half of July, August, and September . As shown in figure 1, this change corresponds in time to the increase in amount (also in fluctu- ability) of the average fishing success. Whether this relationship is a matter of cause and effect or is purely coincidental is open to question. In the winters of 1944-45 and 1945-46 there occurred some rather drastic changes in 39 Table 21,— Water temperature and fishing success* week-to-week averages, sunmer 19^5* Week Beginning Water Temp, at Prairie du Chien ! Fisla/Hour ; Pool 10 June 10 68 : 0.69 17 68 I i 0.69 Zk 73 i 0.73 July 1 72 O.iH 8 72 0.63 15 73 0.79 22 79 0.55 29 79 1.01 Aug. 5 79 0.7^4- 12 80 1.21 19 80 1.4i|. 26 79 1.33 Fish/Hour Total (All Pools) 0.^5 0.37 0.^1 0.28 0.37 O.iJ-5 0.50 0.58 0.^ 0.55 0.65 0.62 Correlation Pool 10 with water temperature: r = 0.62 (P = O.Oi)-) Correlation Total vdth water temperature at Prairie du Chien: r = 0.70 (P » 0.01) 40 the water level of some of the pools, caused by manipulation of the river flow. It can be as- sumed that some of the effects of these suddenly dropped water levels had to do with the catch - ability of the fish. However, no quantitative relationships can be demonstrated with the data at hand. Some of the level manipulations had been completed before the fishing season got well under way, and others took place at various times and in various amounts and places. It is difficult to discern any effects upon the all-over average fishing success (figures 3 and 4) . Weather, moon phases, etc . At various times and by various persons, scientific or otherwise, many heated assertions have been made that fishing success depends upon the weather in general, the air temperature, the wind direction and velocity, the barometric pressure, the degree of cloudiness, the phase of the moon, something with a high-sounding title like "solunar cycles", or any one of a dozen other factors. Eschmeyer (1937) found that the fishing was best when the particular combination of mild air temperature, clear sky, and light wind existed; but he was not able to tell which of these factors was the most important. For an- other season he reported (Eschmeyer, 1935) that he was not able to find a close relationship of the fishing with any of several meteorological factors. Needless to say, in a study such as the present one, the influence, if such there exists, of any one or more of these various factors mentioned above could be assessed with extreme difficulty if at all. The first and foremost poser is the fact that the fishing success for any given day or week varied greatly from place to place within the general area . It is conceivable that some factors such as wind, air temperature, and cloudiness could also vary from place to place at any given time . It is further conceivable, therefore, that there could be a definite covari- ance between some of these factors and the catch of fish; but with the information available, it is almost hopeless to try to demonstrate any such relationship . On the other hand, any such factor as the phase of the moon or the interactions of moon, sun, and tides, would be identical for all of the localities within this area at any given time. (To some extent this would be true also for the barometric pressure, since most of the storms in this region are generalized.) Therefore, any effect upon the fishing exerted by these factors should be uniform throughout the area. Obvious- ly, it is difficult to ascribe poor fishing in one locality and concurrent good fishing in another to the same cause. A set of fishing forecasts (for the sum- mer of 1945) was chosen, one which appeared on a calendar in the form of shaded figures ("the blacker the fish, the better the day for fishing") . Although this forecasting system is only semi- quantitative in nature, a bit of mathematical maneuvering made it possible to obtain a crude statistical relationship between the forecasted fishing success and the actual recorded catch per hour (total averages, all pools),, day by day throughout the summer. The correlation co- efficient turned out to have a (very weakly significant) negative value. In other words, this particular forecast was wrong more often than it was right. Elser (1953) obtained no significant cor- relation between catch and the data of "solunar" tables. Depth of snow. There is some reason to believe that the depth of snow on the ice may exert con- siderable influence upon the amount of winter feeding by the fish and hence upon the fishing success. Heavy snow cover cuts down the amount of light entering the water, and presumably makes it more difficult for fish to find food (or bait) . The desirability of having data on the amount of snow cover occurred to the writer be - latedly; no field measurements of snow depth were made during the creel census operations. There- fore, for any sort of computations regarding the relationship of snow depth to fishing success, reference could be made only to weather station records of "snow on the ground" . These figures for the La Crosse Weather Station for the winter 1944-45, are shown in the graph of figure 3. In a very general way the changes in depth of snow on the ground at the La Crosse station corres- 41 ponded to the changes at other places through- out the area, since most of the winter storms are generalized. However, local precipitation conditions and such factors as blowing and drifting caused some variation in snow depth from place to place. Assuming that the figures as graphed in figure 3 are representative of the entire area, it may be seen from the configuration of the two curves of this figure, representing the amount of snow and the fishing success respectively, that a broad relationship did exist whereby the fishing did tend to become poorer as the snow cover increased. The correlation coefficient was -0.37 (with P somewhat less than 0.01). When the same set of figures for amount of snow on the ground was used in computing the correlation with the fishing success at some of the individual localities, the following results were obtained Fountain City Bay, r= -0.64, P= 0.01; Lake City, r= -0 35, P = more than 0.1; Slough "22", r = zero; Gremore Lake, r = very small . The differences between in- dividual localities may have been due in part to different effects upon different fish species. With the same type of statistical treat- ment, some of the figures for the winter 1945- 46 were: total (all pools), r = very small; Lake City, r = zero; Gremore Lake, r = -0.22, P = 0-2. Thus the correlation which apparently held true in the first winter cannot be demon- strated statistically for the second winter. Relationships and correlations Two successive years. The all-over average fishing success for the two winters 1944-45 and 1945-46 was fairly close to identical, being 0 .54 and 0.46 fish per hour, respectively. As pointed out above, it is difficult to show that the difference was significant. For the 11 localities of table 16 (not including Winter Creek) for which there were data for the two winters, a mathematical correlation does not exist (r = virtually zero) . The localities, therefore, which furnished good (or poor) fishing in the one winter were not necessarily the ones that fur- nished good (or poor) fishing in the next winter. The configuration of the curves repre- senting the week-to-week variation in fishing success for the two successive winteis(figure 4) makes it appear that the trend of changes throughout the winter was similar for the two years. However, a calculation of the correla- tion coefficient (table 22) shows only a weakly significant correlation (r = 0.57; and P = 0.1). Furthermore, for each of two individual local- ities. Lake City and Gremore Lake, the week- to-week correlation coefficient is so small as to have no statistical significance even though there is a suggestion of similarity in the graphs of Gremore Lake for the two winters (figure 5). The tendency of the fishing to fall off following the first few days or weeks of the win- ter season is perhaps significant and apparently is the common rule. It may be related to the fact that the snow cover is usually Ug^t at the beginning of the ice fishing period and tends to increase with successive snowfalls. Another factor which may make a contribution is that the fish at the beginning of the winter have not yet acquired the semi -lethargic state which they ap- parently possess later in the winter and therefore they are still doing some feeding. It must be remembered that the mathematical comparisons just referred to are made on the basis of corres- ponding calendar periods and not necessarily on a phenological basis . The onset of winter con- ditions and the course of events within a body of water throughout the winter may vary by a con- siderable period of calendar time. Figure 6 presents a comparison of the week-to-week fishing success for the two con- secutive summers. There is no statistical correlation and in deed the trends of the two curves have little or no visual similarity. To an even greater extent than in the winter, the sum- mer conditions are apt not to follow the same calendar sequence year by year; particularly such things as flood periods may occupy dates which are considerably different one year from the next. This in turn has an influence upon other factors, such as water turbidity and water temperature. Therefore, it cannot be reason- ably expected that the best (or poorest) fishing will fall within the same week in successive summers. Essentially the same statement has been made by Frey and Vike (1941). 42 Taljle 22. Fishing success, fish per hour, veek-to-week averages* two winter seasons. Week Beginning ^) Total (Al 1 Pools) 19/^5_2^^ Lake City 19i^5_i+6 G-remore Lake l^l\k-h^ 1945-46 Dec. 16 0.97 : 0.65 1.02 0.42 23 0.69 0.54 0.65 0.25 0.22 0.50 30 0.58 0A5 o.J^5 : 0,1^ 0.30 0.31 Jan. 6 0.50 0,3k 0.28 : 0.41 0.32 0.41 13 0.51 O.i^ I 0.36 0.30 20 0.37 0.^^-5 0.2ZJ. ; 0.28 0.16 0.26 27 0.53 0.59 0.25 0.42 0.36 0.84 Feb. 3 0.63 0.31 0.37 0.16 0.07 0.58 10 0.46 0.31 ■ 0.09 0.34 17 0.15 0.38 r = 0 .57 small small P = 0 .1 not significant not sj .gnificant 1) In 1945-46. In the vrinter 1944-45t the corresponding weeks "began on December 17i December 24, etc. 43 -J^o- ^^^ J- 1 J- H 4mw I tf J- z -H jr O 2 4wcy (0 0) -P C ^