Charles M. Kirkpatrick

Salt Preferences and Sodium Drive Phenology in Fox Squirrels and Woodchucks

Salt preferences and sodium (Na) drive were examined in southern Indiana populations of fox squirrels ( Sciurus niger ) and woodchucks ( Marmota monax ). Animal use of salt-impregnated wooden pegs demonstrated that Na compounds were highly preferred. Both seasonal variation in peg use and the phenology of animals licking the road surface for residues of winter-applied sodium chloride demonstrated definite seasonal variation in Na drive. Spring peaks for both species and an additional autumn peak in squirrels were clearly associated with sudden increases in dietary intake of potassium (K) in spring and decreases in Na intake in squirrels in autumn. The high K intake is postulated to interfere with otherwise efficient Na-conserving mechanisms.

Age Criteria in Male Gray Squirrels

ALLEE, W. C., A. E. EMERSON, O. PARK, T. PARK, AND K. P. SCHMIDT. 1949. Principles of animal ecology. Philadelphia: W. B. Saunders Co. 837pp. ALLEN, D. L. 1943. Michigan fox squirrel management. Mich. Dept. Cons., Game Div. Publ. 100. 404pp. BROWN, L. G. AND L. E. YEAGER. 1945. Fox squirrels and gray squirrels in Illinois. Ill. Nat. Hist. Surv., 23(5):449-532. BUMP, GARDINER, R. W. DARROW, F. C. EDMINSTER, AND W. F. CRISSEY. 1947. The ruffed grouse--life history, propagation, management. Albany: N.Y. State Cons. Dept. 915pp. LINDUSKA, J. P. 1947. Winter den studies of the cottontail in southern Michigan. Ecology, 28(4):448-454. MORAN, R. J. 1952. A refuge squirrel population in southern Illinois. 14th Midwest Wildl. Conf., Des Moines. 1-7pp. PETRIDES, G. A. 1949. Viewpoints on the analysis of open season sex and age ratios. Trans. N. Amer. Wildl. Conf., 14:391-410. SHORTON, MONICA. 1951. Some aspects of the biology of the grey squirrel (Sciurus carolinensis) in Great Britain. Proc. Zool. Soc. London, 121(2):427-459. UHLIG, H. G. 1956a. Effect of legal restrictions and hunting on gray squirrel populations in West Virginia. Trans. N. Amer. Wildl. Conf., 21:330-338.

Coprophagy in the Cottontail

Coprophagy in the swamp rabbit ( Sylvilagus palustris paludicola ) as noted by Hamilton (Jour. Mamm., 36: 303, 1955) confirms the suspicion of Watson and Taylor (Science, 121: 314, Feb. 25,1955) that some of the North American Lagomorpha would be found to indulge in the habit of reingesting their own fecal pellets. The present note, encouraged by Dr. W. J. Hamilton, Jr., lends weight to. his assumption that “coprophagy is common to many North American lagomorphs.” In February and March, 1950, and again in …

Seasonal Changes in Thyroid Gland Morphology of Male Gray Squirrels

In a previous paper (Kirkpatrick and Hoffman, 1960), we presented data indicating that male gray squirrels (Sciurus carolinensis) attain sexual maturity at about 10-11 months of age. Males from spring litters remain sexually active longer than those from summer litters. Following a period of sexual activity of 3-8 months, all males enter a period of sexual decline in the summer, reaching a quiescent stage characterized by non-functional reproductive organs. Approximately 2 months later (October), sexual redevelopment begins, marked by reenlargement of organs and new proliferation of germinal and secretory epithelium (Kirkpatrick, 1955; Mossman, et al., 1955). The period of adult redevelopment coincides with initial development of spring juveniles resulting, in December, in a general primeness of all but summer-born males. Hence, it appears that initial sexual development is age-connected, in part, but redevelopment must have another stimulus. Body weight is not important as an indicator of the physical conditioning required for sexual development (Kirkpatrick and Hoffman, 1960). Further studies, undertaken to ascertain the hormonal or environmental factors which might influence sexual activity, provide the data presented here. The purpose of this paper is to consider the thyroid gland of male squirrels in connection with changes in their sexual activity or ages, and as related to seasons. The influence of the thyroid gland on reproductive processes has long been recognized and recently reviewed by Maqsood (1952). As a general rule, increased cell height is directly correlated with increased thyroid gland function. For the present study, thyroid cell height was measured in male gray squirrels collected each month, comprising two ages and various sexual development classifications. Other studies are now in progress relating to adrenal, thymus and pituitary changes.

A Determination of Hole Sizes Which Exclude Certain Predatory Mammals

On several occasions the authors have been called upon to give information to poultry raisers relative to fencing material which will give protection against various kinds of predatory mammals. One type of poultry rearing, the rangeshelter method, is particularly vulnerable to the depredations of carnivorous mammals including domestic cats and dogs. Under this kind of management large numbers of chickens are placed on open pasture range and supplied at intervals over the area with roosting shelters consisting of a metal roof and sides usually of woven wire. When the fowls enter these shelters at dusk, an attendant fastens a door to secure them, and releases them early in the morning. Thus the birds are generally safe from night predators although the degree of safety may depend upon numerous environmental conditions such as location of the range relative to cover, dens, etc.; strength of the wire and size of mesh; predator density; and vigilance of the attendant. Of all these, perhaps the one condition easiest to control, and when controlled will provide greatest safety, is the sound construction of shelters. To construct a predator-proof shelter with sides and bottom of wire requires some knowledge of the kind of material that will exclude possible raiders. The repellent qualities of the wire must be known in terms of wire size as well as

Effect of Simulated Gunshot Injuries on Reproduction of Game Farm Bobwhites

By means of fluoroscopy, Whitlock and Miller (1947), and Elder (1950) have shown that as much as 30 percent of some species of ducks, available from live-trapping and botulism work, are carrying lead shot in their tissues as a result of gunfire. While the migratory ability of such ducks does not appear to be affected, what can be said about their breeding capacity? Is it impaired by lead shot embedded in their tissues? Mindful of the fluctuating quail population and the ever increasing gun pressure, the question also applies to quail. Phylogenetically, ducks and quail are remotely situated, but their fate at the hands of the hunter is similar. The more hunters afield, the more shots will be taken at quail, and the more crippling will result. As in the case of waterfowl

Some Comparisons of Thyroid Glands of Bobwhites and Japanese Quail

CHEATUM, E. L. AND C. W. SEVERINGHAUS. 1950. Variations in fertility of white-tailed deer related to range conditions. Trans. 15th N. Am. Wildl. Conf.: 170-190. CHRISTISEN, D. M. AND L. J. KORSCHGEN. 1955. Acorn yields and wildlife usage in Missouri. Trans. 20th N. Am. Wildl. Conf.: 337-357. DALKE, P. D. 1941. The use and availability of the more common winter deer browse plants in the Missouri Ozarks. Trans. 6th N. Am. Wildl. Conf.: 155-160. DEXTER, R. W., S. J. CORTESE, AND S. A. REED. 1952. An analysis of food habits of whitetailed deer. Ohio Wildl. Investigations. Dept. of Natural Resources, Columbus. 3 (3):34-39. DowNs, A. A. 1949. Trees and food from acorns. Yearbook of Agriculture, 571-573. DUNKESON, R. L. 1955. Deer range appraisal for the Missouri Ozarks. J. Wildl. Mgrnt., 19(3):358-364. FERNALD, M. L. 1950. Grays Manual of Botany. Eighth Edition. American Book Co., New York. 1,632pp. HAHN, H. C. 1945. The white-tailed deer in the Edwards Plateau of Texas. Texas Game, Fish and Oyster Comm., Austin. 50pp. HAMMAR, C. H., W. J. ROTH, AND O. R. JOHNSON. 1947. Types of farming in Missouri. Univ. of Mo., Agr. Exp. Sta. Res. Bull. 284. 100pp. HILL, R. R. AND D. HARRIs. 1943. Food preferences of Black Hills deer. J. Wildl. Mgmt., 7(2) :233-235. KING, D. B., E. V. ROBERTS, AND R. K. WINTERS. 1949. Forest resources and industries of Missouri. Univ. of Mo., Agr. Exp. Sta. Res. Bull. 452:12. LINDZEY, J. S. 1952. The white-tailed deer in Oklahoma, Okla. Game and Fish Dept. Bull., Oklahoma City, 105pp. MCKEAN, W. T. 1945. Winter deer problem. S. Dak. Cons. Digest, Jan.:2-3, 6. MILLER, M. F. AND H. H. KRUSEKOPF. 1929. The soils of Missouri. Univ. of Mo., Agr. Exp. Sta. Bull. 264, 120pp. MURPHY, D. A. 1959. A study of deer use of available forage in Missouri. Cons. Comm., P-R Surveys and Investigations Projects, Mo. 13-R (Typewritten) Columbia, Mo., 14pp. PEARSON, A. M. 1943. White-tails like acorns. Ala. Conservation, 15(6) :8-9, 12. AND C. R. BURNETT. 1940. Deer food in the Black Warrior National Forest. Ala. Game and Fish News, 11(8):3-4.