Free-ranging mammals

Experimental modulation of behavior of free-ranging mammals by semio-chemicals. In Chemical Signals in Vertebrates, vol. 3, ed. D. Muller-Schwarze, and R. M. Silverstein, pp. 235-244. New York Plenum. 

Scent Marking in Free-Ranging Mammals. Examples Beaver or Badger... 

This real-world exercise tests the efficacy of a feeding repellent in free-ranging mammals. It constitutes the counterpart to the repellent effect of methyl anthranilate on feeding by birds (see Chap. 3). The experiment works at any place with wild squirrels and in any season. The many mammal repellents on the market are aimed against deer, predators such as raccoons, foxes and coyotes, and rodents such as voles, mice, squirrels, woodchucks, and others. Mammal repellents are known under names such as copper naphthenate, trimethacarb, zinc naphthenate, and ziram. 

Irradiated small mammals released into the environment had a lower survival rate than laboratory populations, suggesting that the extrapolation from laboratory results may overestimate the radioresistance of free-ranging voles and other small animals because of the general level of stress in the population (Iverson and Turner 1976). The opposite was observed in eastern chipmunks given high sublethal doses of X-rays. Chipmunks had an overall reduction in mobility when they were released... 

In black-tailed deer, Odocoikus hemionus columbianus, fecal odors of sympatric predators (coyote, C. latrans, and mountain lion, Fdis concolor) in vials next to food pellets inhibited feeding, while those of allopatric predators (lion, Fdis leo, snow leopard, Uncia uncia) do not, or very little (Miiller-Schwarze, 1972 Fig. 12.3). Note that mammals discriminate between the odors of sym- and allopatric predators, while fish and rattlesnakes do not (pp. 359 and 364). Free-ranging adult female wapiti, Cervus elaphus canadensis, respond to the odors of dog urine, and cougar and wolf feces (presented as water slurry) with increased heart rates. It was concluded that the main effect of predator odors may be for assessing the risk of predation (Chabot etal, 1996). 

Thompson, D., and M.A. Fedak (1989). Comparison of dive behaviour and cardiac responses of free ranging harbor and grey seals. Tenth Biennial Conf. Biol. Marine Mammals A106. 

Seals and Other Marine Mammals. Among the effects of CACs reported on free-ranging seals are skeletal deformities and impaired reproduction. Captive seals fed with CAC contaminated hsh showed a significantly reduced reproductive success compared to animals fed with clean hsh.93 Vitamin A and thyroid hormone levels were also signihcantly reduced.89 These hndings corresponded to results of experimental studies with mink and rodents exposed to PCBs. 

Kimball, B.A., D.L. Nolte, R.M. Engeman, J.J. Johnston F.R. Stermitz. 1998. Chemically mediated foraging preference of free ranging black bears Ursus americanus). J. Mammal. 79 in press. 

Ceramidases are enzymes that cleave the N-acyl linkage of Cer into SPH and free fatty acid. They are an emerging class of enzymes composed of multiple isoforms. Historically, these isoforms have been classified as acid, neutral or alkaline, based on the pH optimum of their activities although some isoforms show activity in a broad range. With the recent cloning of several isoforms from yeast, bacteria, and mammals, a genetical distinction and classification of these enzymes can now be employed. 

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