Gisela Epple

Why are predator urines aversive to prey

Predator odors often repel prey species. In the present experiments, we investigated whether changes in the diet of a predator, the coyote (Canis latrans) would affect the repellency of its urine. Furthermore, because predator odors have a high sulfur content, reflecting large amounts of meat in the diet, we investigated the contribution of sulfurous odors to repellency. Our results were consistent with the hypothesis that diet composition and sulfurous metabolites of meat digestion are important for the repellency of predator odors to potential prey.

Detection of the chemical signals of ovulation in the cotton-top tamarin, Saguinus oedipus

Abstract Abstract. Behavioural, visual or chemical signalling of the ovulatory period occurs in most mammalian species. In primates, the type of signalling has been linked to mating strategies. It has been suggested that monogamous and polyandrous primates conceal evidence of the periovulatory period. Cotton-top tamarins, Saguinus oedipus , do not display visual or consistent changes in sexual behavioural cues indicating the periovulatory period, although conceptions occur on 84% of all post-partum ovulations in captivity. To examine the possibility that olfactory cues of ovulation are used to signal other tamarins of the females reproductive status, daily scent marks were collected from a donor female during the ovulatory cycle and transferred to the home cage of eight male-female pairs for testing. Recipient females contacted the platform containing the scent mark significantly more often during the periovulatory period (3 days around the urinary luteinizing hormone peak of the donor female) than the non-periovulatory period (the rest of the cycle: follicular and luteal). Recipient males increased the frequency of mounts of the cagemate female and penile erection rates were significantly higher during the donor females periovulatory period. These results provide evidence that there is a direct olfactory cue of ovulation in female tamarins and that this cue affects the males sexual behaviour. This evidence does not support the theory of concealed ovulation since the monogamous cotton-top tamarin appears to signal the timing of ovulation.

Effects of Predator Odors on Feeding in the Mountain Beaver ( Aplodontia rufa )

Consumption of food by Aplodontia rufa from bowls scented with control odors, secretion from anal glands of minks ( Mustela vison ) or urine from minks, bobcats ( Felis rufus ) and coyotes ( Canis latrans ) was studied. In two-choice control tests, subjects indiscriminately consumed apple from unscented bowls and from bowls scented with urine from an unfamiliar herbivore ( Cavia porcellus ), or with butyric acid. During two-choice tests offering apple from bowls scented with secretion from anal glands of minks and from bowls scented with butyric acid, significantly less apple was consumed from bowls containing mink scent. In two-choice tests in which apple was offered from bowls scented with urine from either mink, bobcat, coyote, or domestic dog, all predator urines reduced feeding. Habituation was studied by measuring consumption of dry pellets during continuous exposure to coyote urine for 5 days. Significantly less chow was consumed from bowls scented with coyote urine than from control bowls, indicating a lack of habituation to the predator scent. We conclude that predator scents act as natural repellents. The responsiveness to scents from several sympatric predators as well as from domestic dogs suggest an innate reaction to a signal, which is common to carnivores. The utility of predator scents in the control of browsing damage by mountain beavers should be explored.

AMBIENT ODORS ASSOCIATED TO FAILURE INFLUENCE COGNITIVE PERFORMANCE IN CHILDREN

We investigated whether odors can become conditioned to emotionally salient experiences such that when later encountered they influence performance consistent with a previously associated event. To test this hypothesis, 5-year-olds were given the experience of failure/frustration on a cognitive maze in a room scented with fragrance and later given another cognitively challenging test in a different room scented with either the same odor, a different odor, or no odor. Results revealed that subjects who performed the test in the presence of the same odor as the maze task did significantly worse than subjects in any other group. Performance in the different odor and the no odor groups were equivalent. Facial expressions and verbal remarks made during the maze task indicated a predominant display of negative affect. These findings show that odors can become conditioned to experiential states and when later encountered have directional influences on behavior.

OLFACTORY COMMUNICATION IN SOUTH AMERICAN PRIMATES

For the researcher interested in the role of olfactory communication in primate social and sexual life, South American monkeys represent a reservoir of highly interesting models. Their communication systems seem to rely more heavily on olfactory signals than do those of most Old World monkeys and apes. All neotropical species are arboreal. The n i g h monkey (Aotus trivirgatus) is also nocturnal. Thus, South American monkeys live in an environment in which they cannot always easily communicate by visual signals, Moreover, compared with Old World primates, many species do not possess very large repertoires of facial expressions and visual displays. These facts might well favor the use of chemical signals in certain areas of behavior. Chemical signals may be contained and discharged in several body products. Urine and saliva apparently are carriers of information. In addition, most genera of neotropical primates possess specialized skin glands producing odoriferous secretions.17~ 1R.21, 90-49, 48,61.66, 66 In a large number of species, scent-marking b e havior has been observed. This behavior is concerned with the emission and a p plication of urine, saliva, and the secretions of the specialized scent glands to their own bodies, to that of sexual and social partners, and to the environment (see references below). Chemical signals are probably predominantly perceived by olfaction. Many observers, however, report that the investigation of chemical stimuli such as scent marks, urine, or the bodies and genitalia of conspecifics not only includes sniffing, but also licking and even ingestion of material. Thus, besides olfaction, taste and perception via the vomeronasal organ might be involved.16 Although various patterns of scent marking and of investigating conspecific chemical stimuli have been described in many neotropical primates, the function of these stimuli is very poorly understood and has rarely been studied experimentally. The situations in which these behavior patterns occur, however, suggest that the chemical signals involved play quite important roles in the sexual and social life of neotropical primates. This paper will review the biological role of chemical communication in New World primates, which means that the author will mostly discuss and try to interpret reports of behavioral patterns that suggest certain functions in chemical communication. Much of the interpretation, based on preliminary data, will necessarily be speculative and might have to be revised as our knowledge increases and more experimental data become available.

Lack of effects of castration on scent marking, displays, and aggression in a South American primate (Saguinus fuscicollis).

Abstract The social interactions of 12 adult, permanently cohabiting male-female pairs with strange conspecifics were studied before and after the male of each pair was either castrated or underwent control surgery. Prior to surgery, the pairs directed a relatively high amount of injurious aggression and displays toward the stranger. Aggression, display behavior, and scent marking tended to be more frequent in females. Moreover, female strangers received more aggression than male strangers, particularly by female subjects. Castration of the males did not result in a decrease in aggression, display behavior, and scent marking. On the contrary, the agression scores of all subjects tended to be higher after surgery, an increase which was probably caused by extraexperimental variables.

Social influences on first reproductive success and related behaviors in the saddle-back tamarin (Saguinus fuscicollis, callitrichidae)

Some aspects of sociosexual behavior and the age at which maturing females experienced their first evident pregnancy and at which maturing males caused their first evident pregnancy were recorded in Saguinus fuscicolliscohabiting from 6 months of age with either an adult or a maturing sex partner. The following pair combinations and trios were studied: young male -young female, young male-adult female, adult male-young female, and adult male-young male-young female. The most frequent type of social interaction between young animals was rough and tumble play, while huddling was the most frequent interaction between young animals and their adult partners. Grooming and sexual interactions were very infrequent and there were no differences in the frequencies of these interactions among subject groups. Maturing females cohabiting with an adult male conceived significantly earlier than maturing females cohabiting with a male of their own age. Maturing males cohabiting with adult females sired offspring at a significantly earlier age than males cohabiting with a female of their own age. Some possible behavioral and physiological processes involved in the causation of early reproductive success in young tamarins cohabiting with adults are discussed.

Analysis of chemical signals in a primate species (Saguinus fuscicollis): Use of behavioral, chemical, and pattern recognition methods.

Scent marking with specialized skin glands is a common behavior in the tamarin,Saguinus fuscicollis. The scent marks identify species, subspecies, gender, and individual, and they also contain information on the social position and hormonal condition of an animal. The marks are chemically complex, containing a large number of compounds. Analysis by means of gas chromatography-mass spectrometry has identified 16 major components (squalene and 15 esters of butyric acid). These compounds are present in the marks of males and females of two subspecies,Saguinus f. fuscicollis andSaguinus f. illigeri. Application of computerized pattern recognition techniques has shown that concentration patterns of some of the butyrates are diagnostic of the two subspecies while concentration patterns of other butyrates are diagnostic of males and females regardless of subspecies. Behavioral studies have shown that the concentration patterns of butyrates and squalene alone do not encode information on subspecies and gender. It is, however, likely that this information is partially encoded by these specific butyrate-squalene concentration patterns but that yet unidentified compounds in the scent marks serve as necessary synergists.

Potential repellents to prevent mountain beaver damage

Mountain beaver (Aplodontia rufa) damage to trees in the Pacific Northwest is economically serious. At present, few strategies are available to control damage, and new chemical repellents are being sought. Samples of two preferred plants, Douglas fir (Pseudotsuga menziesii) and salal (Galtheria shallon), were treated with mink urine, coyote urine, o-aminoacetophenone, or denatonium benzoate and presented to mountain beavers. All treatments reduced clipping (p < 0.05) of salal, but mink and coyote urines were most effective. Mink and coyote urines were the only treatments to significantly reduce clipping (p < 0.05) of Douglas fir.

The Saddle Back Tamarin and other Tamarins

For many decades, various species of marmosets and tamarins, members of the family Callitrichidae, have been kept in captivity. Early on these animals were mostly kept as pets or were exhibited in zoological gardens1. Although early attempts to maintain and breed marmosets and tamarins for extended periods of time under captive conditions met with limited success, they have gradually increased our knowledge of the behavior and of the dietary and environmental requirements of callitrichids. More recently, biomedical and behavioral researchers have become interested in these small monkeys and in their potential as laboratory primates. As a result of their studies, our expertise in the maintenance of callitrichids in captivity has increased considerably2–8.