U the -1*. 2.Manage- ment Dste Thesis pr.. nt .1( Title--T -].Lt etract Signature redacted for privacy. (Jjop ?o*asoz') Purpose The main purpose of this study was to ascertain theimportance of the domestic cat in theWillamette Valley as a game bird,predator; 4ditjonal reasonswere to learn more of its lifehistory and food habits, and to analyze thepopular belief that the cat,feral or non-feral, is thegreatest predator of birdlife known. Location Study The region in ftiichinvestigation was made was the Willamette Valley, Oregon, which issituated 40 miles inland from the Pacific Ocean, in the northwest quarter oftheState of Oregon. Investigatjon Procedure The following seven methodswere used in obtaining neeessaa'y data: A detailed. review of imi],ar past studiesotthe cat aaa predator. A census of 416 farms. Informationfrom 425 4-H Club questionnaires. Field observatioris. Trapping and hunting of cats forspecimens for stomach analysis. Identification of food items in cat coats. Stomach analysis by Charles C. Sperry,Associate Biologist, United States Bureau of Biological Survey. Summary FindiEs 1. There are approximately 94,000 farm cats in the Willamette Valley, or an average of 2.85 cats per farm. The feralc at population in the Willamette Valley is estimated at approximately 11,000. Total population of feral and non-feral cats for the entire Valley, exclusive of cities and towns,is conservatively estimated as being over 100,000. The average female farm cat has two litters annually, with a mean average of 4.85 kittens per litter. Most farmers value their cats as mousers at $10.00to $50.00 annually. camination of 63 cat scats shed that 55.6 percent of the material by occurrence was principally of rodent origin. Fifteen field mice were identifiedout of atotal of 35 rodents. The food items found from stomach analysis of 86 cats were principally confined to the Order Rodentia, in which five species made up by volume 45.09 percent ofthetotal food examined.Field mice,Microtus ., werefound in 26 stomachs (22.85 percent),and theOregon brushrabbit, Sylvi1aus bacbmani uberióolor (Miller), was second in being found in 11 stomachs (12.12percent). Only two California quail, Loihortyx californica vallicola (Shaw),and western mourning dove, Zenaidura niacroura marginella (Woodhouse), was found, making 3.37 percent the total volume for game birds. Conclusion The most important general conclusion reached in this 2.nvestl- gation is that the stomach analyses of the feral and rural eat do not bear ai t the contention that the domestic cat in the Willamette Valley is a confirmed game bird consumer. THE ROLE OF THE DOMESTIC CAT IN RELATION TO GAME BIRDS IN THE WILLAMETTE VALLEY, OREGON by Nils Norman Nilsson A THESIS submitted to the OREGON STATE COLLEGE in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE June 1940 ACOTLEDGLT;ENTS This opportunity is taken to thank Mr. Arthur S. Einarsen, Leader of the Oregon Wildlife Cooperative Research Unit, under whose supervision this investigation was conducted.A great deal of credit is due Professor R. E. Dimick, Head of the Fish and Game Department, Oregon State College, for many timely suggestions and for critically reading this paper. The helpfulness of Mr. E. H. Kaimbach, in charge of the Denver Laboratory of Food Habits Research, United States Bureau of Biological Survey, and Mr. Charles C. Sperry, Associate Biologist, in the examination and identification of stomach con- tents from the majority of specimens collected during this study is greatly appreciated. Acknowledgement is made to the Oregon Cooperative Wildlife Research Unit, without whose financial aid this investigation would have been impossible. Thanks are also due the many farmers, pet owners and trappers throughout the Willamette Valley, Oregon, for contributing valuable information. TABLE OF CONTENTS Page Introduction 1 General Description of the Willamette Valley, Oregon 2 Review of Literature 4 Fecundity of the Cat 6 Breeding Habits 6 Gestation Period 6 Breeding and Wielpirig Season 7 Weaning Time 7 Minimum Breeding Age 7 Maximum Breeding Age 7 Numbers of Litters Each Year 8 Number of Young in Each Litter 8 Breeding in the Wild 9 Numbers of Cats 10 Farm Cats 10 Feral Cats 11 Estimated Number of Farm and Feral Cats 14 Surplus Cats and Kittens 16 Abandoning Practices 16 The Cat as a Predator 20 Patience 20 Method of Attack 21 Food Capacity of the Cat 23 Egg Eating Habit 30 Number of Birds Killed by Cats 31 Evaluation of the Farm Cat 33 Cover Importance 34 Cruising Range 36 Sex Ratio of Trapped Cats 3'7 Food Study Habits 38 Methods of Collection 38 Methods of Study 39 Scat Analysis $9 Identification of Cat Kills 42 TABLE OF CONTENTS Page StomachAnalysis 42 Food Predilections of the Wildcat and Domestic Cat 46 Legal Status of the Cat 53 General Discussion and Conclusions 58 Appendix 63 IndividualStomach Analysis Records 63 Figures and Tables Figure 1. An Empty Cat's Stomach Compared with a Full One 28 Figure 2. Interior View of Full Stomach 29 Figure 3. A Farm Cat 15 Figure 4. A Feral Cat 15 Figure 5. Remains of a Pheasant Cat Kill 32 Figure 6. A Fresh Pheasant Cat Kill 32 Figure 7. Final Summary of Wildcat's Food 52 Figure 8.. Final Summary of Feral and Non-feral Cat's Food 52 Figure 9. Summary of occurrence of Food Items Found in 63 Cat Seats 4]. Table I. Distinguishing Characteristics of Rural and Feral Cats 13 Table II. Summary, Showing Parts Eaten and Parts Not Eaten by Six Individual Cats 26 Table III. Items of Food Identified in the Stomachs of 86 Domestic Cats 47 THE ROLE OF THE DOMESTIC CAT IN RELATION TO GAME BIRDS IN THE WILLAMETTE VALLEY, OREGON Introduction A study of the habits of the domestic cat was conducted in the Willamette Valley, Oregon, on a part-time basis, from November 1, 1938, to March 1, 1940, for the purpose of ascertaining the importance of this animal as a game bird predator. Additional reasons for undertaking this investigation were, to learn more of the life history and food habits of the domestic cat in Oregon; to analyze the popular belief of many persons in sportsmen's organizations that the domestic cat is very destructive to game and song birds; and to place the cat problem in its correct classification in upland game management. Practically no facts were known about the cat as a predator in Oregon previous to this study. There seems to be a widely accepted belief, however, that the cat, feral or non-feral, is the greatest predator of birdlife known. This paper is presented as an attempt to analyze the problems involved with cats in game bird management. 2 General Description of the Willamette Valley,Oregon The region selected for investigation wasthe Willamette Valley, which is situatedapproximately 40 miles inland from the Pacific Ocean, in thenorthwest auarter of the State of Oregon. Rogers (8) states that "The WillainetteValley is almost rectangular in shape. Its northern boundary is the Colunibia River, into which theWillamette River flows at Portland. The eastern boundary is the Cascade Divide; the southern boundary is the CalapopyaDivide, which separates the Willatnette Valley from the Umpqua Valley; and the western boundary is the crest of the Coast Range, which parallels the shore ofthe Pacific Ocean. The Willamette River flows northward alongthe floor of the valley, dividing it into two parts. One of these, on the east slope of the Coast Range, in- cludes about one-fourth of the drainage area, andthe other, on the west slope of the Cascades, includesthe remaining three-fourths." The general width of the valley is approximately 40 miles and it is about 140 miles in length. The approximate total area is some 2,?50 square miles. The climate of this section of Oregon is best described as being mild. The United States Weather Bureau gives the mean annual temperature as 51.50 3 Fahrenheit, with a mean temperature for the winter months of 40,10 Fahrenheit. The average growing sea- son is 182 days, with a mean yearly rainfall of 45.6 inches. The rains come intermittently during the fall and winter months. Snowstorms are infrequent, the snow covering the ground for but a short period when present. Agricultural pursuits predominate over the entire valley. The leading crops are grain, hay, grasses for seed, fruit and truck garden crops. Dairying, poultry and livestock enterprises are quite common throughout the area. The characteristic cover found within the valley is primarily evergreen and deciduous trees and shrubs. Abundance of bird cover is found along the fence rows, in numerous swabs and in woodlots. Out- side of the great variety of weeds, many areas are covered with Rosa spp. and Rubus spp. The Willamette Valley is noted, from a game bird standpoint, as being the place where the first successful introduction of Chinese ring-necked pheasants was made in the United States. In 1880 Judge 0. N. Denny, then United States Consul General at Shanghai, shipped Chinese pheasants to Oregon but this shipment did not establish themselves. Two years 4 later, according to Simpson (9), Judge Denny sent another shipment of 18 female aid 10 male pheasants, which were released in Linn County, and the birds es- tablished themselves at once. Simpson states that ten years after this release, in one year, over 30,000 were killed in one county during the first hunting season. Review of Literature When a search of the published material re- garding the domestic cat is made it is very evident that there has been but little study in the past years of the habits of the domestic cat as a predator of up- land game and song birds.