Coyote urine

Chemical Fractionation. The frozen urine was thawed and pooled In one 50 a batch for chemical fractionation. It was made basic (pH 12) with potassium hydroxide and the basic and neutral compounds extracted with diethyl ether according to the extraction scheme outlined In Figure 1. The gel fraction separated from the coyote urine after It had been made basic and was recovered by filtration of the basic urine. The basic compounds were separated by extraction with 6N hydrochloric acid leaving the neutral compounds in the ether residue. The original ether extracted basic urine was then made acid (pH 2) and the acidic compounds extracted with diethyl ether. The acidic, basic and neutral fractions were stripped of ether solvent by distillation. 

The chromatogram by gas-liquid chromatography. Figure 9, indicated over thirty major peaks or chemical compounds in the acids fraction of the estrus coyote urine. Mass spectral data permitted tentative identification of the methyl esters of a series of short chain fatty acids, C2-C- g, together with aromatic compounds as present. Table 1 lists 19 tentative identifications of compounds in the acids fraction. Because other investigators ) have reported that an artificial mixture of similar fatty acids demonstrated significant attraction of coyotes it will be interesting to prepare a mixture of the fatty acids identified in coyote urine in the exact ratio that they are in... 

A mammal may emit many volatile compounds. Humans, for instance, give off hundreds of volatiles, many of them chemically identified (Ellin etal., 1974). The volatiles include many classes of compound such as acids (gerbil), ketones, lactones, sulfides (golden hamster), phenolics (beaver, elephant), acetates (mouse), terpenes (elephant), butyrate esters (tamarins), among others. The human samples mentioned before contained hydrocarbons, unsaturated hydrocarbons, alcohols, acids, ketones, aldehydes, esters, nitriles, aromatics, heterocyclics, sulfur compounds, ethers, and halogenated hydrocarbons. Sulfur compounds are found in carnivores, such as foxes, coyotes, or mustelids. The major volatile compound in urine of female coyotes, Canis latrans, is methyl 3-methylhut-3-enyl sulfide, which accounts for at least 50% of all urinary volatiles (Schultz etal, 1988). 

FIGURE 6.9 A signature urine mark (left center) on a snow bank made by a coyote. To the right, the animal has defecated, pawed, and partially covered the feces with snow. (Photograph D. Miiller-Schwarze.)... 

Coyote Canis latrans Urine marks RLU Bowen, 1978... 

In coyotes, C. latrans, SQTJ by females is associated with acquisition and possession of food, and the denning season (Wells and Bekoff, 1981). Red foxes, Y. vulpes, urine mark a buried food cache at each visit the more depleted it is, the more urine odor has accumulated, amounting to book-keeping (Henry, 1980). Foxes urine mark inedible food remains on repeated visits. This no-food-left signal, in turn, decreases the foxes interest, and they investigate the site very little (Henry, 1980). Here, an animal may chemo-communicate with itself about food. Wolves, C. lupus, also urine mark their food caches (Harrington, 1981). 

Free-ranging North American beaver. Castor canadensis, feed less on experimental aspen sticks that have been treated with extracts from predator excrement or urine. Odors from the sympatric coyote and river otter, and extirpated lynx, were most effective, while those from allopatric lion and extirpated wolf odor were less active. However, these response differences between species were small (Fig. 12.2 Engelhart and Muller-Schwarze 1995). 

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). 

Mountain beaver, Aplodontia rufa, a primitive rodent from northwestern North America, fed less from food bowls if the rim was scented with mink anal gland secretion, or urine from mink, bobcat, coyote, or dog. The control odors butyric acid or guinea pig urine had no effect (Epple et fl/., 1993). Mountain beaver did not respond significantly to mustelid sulfur compounds though, yet these deter other small mammals (Epple etal, 1993). 

Both male and female coyotes, C. latrans, are attracted to volatile aldehydes from sheep liver and estrous urine of female coyotes. The most active compoimds were octanal, nonanal, decanal, and imdecanal. The aldehydes released sniffing and rub-rolling, but little lick-chewing and biting. Therefore, these compoimds are better suited to attract coyotes to traps than to toxicant-delivery systems that rely on the latter behaviors (Scrivnereta/., 1984). 

Coyote scent (urine) stations also attracted cottontail rabbits Sylvilagus flori-danus. In Texas, this behavior has aided rabbit censuses. The scent station count is more accurate than the traditional headlight count but more labor intensive... 

Schultz, T. H., Flath, R. A., Stern, D. J., etal. (1988). Coyote estrous urine volatiles.JournaZ of Chemical Ecology 14,701-712. 

The first experiment assessed whether diet manipulations affect the repellency of a predator urine to several prey species. Four rodents served as subjects mountain beaver, house mice, deer mice and guinea pigs. Urine was collected from coyotes maintained on cantaloupe (CU) for 2 weeks and then from the same coyotes fed minced raw meat (MU) for two weeks. Test procedures were similar for all species, though food and deprivation schedules varied. On each of 2 pretreatment days, animals were given their respective foods in cups containing perforated containers with a piece of absorbent paper treated with 1 ml of tap water. On the 2 treatment days that followed, the animals were given the same foods, but the absorbent paper was treated with 1 ml of either CU or MU. Urine samples (1 ml) were pipetted onto pieces of absorbent paper placed inside small (38 mm diameter x 8 mm) perforated plastic containers. For all individuals of each species, the left-right position of CU urine samples was randomly determined on day 1, and then reversed on day 2. The data for each species was evaluated separately in a two-factor repeated measures ANOVA. In each case, urine type was the main effect, with the animals nested within urine type and the repeated measure was days. 

Diet manipulation experiments showed that the presence of meat in a donor coyote s diet increased the repellency of the urine. This result led us to hypothesize that byproducts of meat digestion in urine (e.g., sulfur compounds) might contribute to aversiveness. To test this hypothesis, we removed sulfur-containing substances from MU by precipitation with mercuric chloride. The responses of mountain beaver to urine stimuli with and without sulfur compounds were then... 

Table I. Methyl Esters of Coyote Estrus Urine Acids ...

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