Scent marking behaviors

We have found that foraging bumblebees (Bombus hortorum, B. pascuorum, B. pratorum and B. terrestris) not only avoid ¯owers of Symphytum o - cinale that have recently been visited by conspeci®cs but also those that have been recently visited by heterospe-ci®cs. We ...

We tested several alternative hypotheses about the function of scent marking by the North American river otter, Lontra canadensis. Otters may mark at latrine sites with spraints (faeces) to (1) signal species identity, (2) advertise their reproductive status, (3) establish and maintain territories, and (4) communicate social status and identity to group members. Olfactory preference tests were conducted at the

The capacity for cone-mediated color vision varies among nocturnal primates. Some species are col- orblind, having lost the functionality of their short-wavelength-sensitive-1 (SWS1) opsin pigment gene. In other species, such as the aye-aye (Daubentonia madagascariensis), the SWS1 gene re- mains intact. Recent studies focused on aye-ayes indicate that this gene has been maintained by natural selection and that the pigment has a peak sensitivity (λmax) of 406 nm, which is ∼20 nm closer to the ultraviolet region of the spectrum than in most primates. The functional significance behind the retention and unusual λmax of this opsin pigment is unknown, and it is perplexing given that all mammals are presumed to be colorblind in the dark. Here we comment on this puzzle and discuss recent findings on the color vision intensity thresholds of terrestrial vertebrates with com- parable optics to aye-ayes. We draw attention to the twilight activities of aye-ayes and report that twilight is enriched in short-wavelength (bluish) light. We also show that the intensity of twilight and full moonlight is probably sufficient to support cone-mediated color vision. We speculate that the intact SWS1 opsin pigment gene of aye-ayes is a crepuscular adaptation and we report on the blueness of potential visual targets, such as scent marks and the brilliant blue arils of Ravenala madagascariensis.

Subadult intruding beavers (Castor spp.) could be expected to pose a higher threat than adults to territory holders because, unlike adults who usually own a territory, subadults need to acquire a territory and a mate to reproduce successfully. We tested the responses of territorial beavers ( Castor canadensis Kuhl, 1820) to simulated intrusions by adult and subadult males. Territorial intrusion was simulated through scent playback experiments that exposed residents to castoreum from adult and subadult strangers simultaneously. We obtained responses from 13 resident beavers. Neither sniffing response nor physical or total responses differed between castoreum from adults and subadults. This was true for both sexes combined and separate. There was also no significant correlation between the mass of the scent donor and the response intensity. We found no evidence that territorial beavers responded differentially to castoreum scent marks from intruders of different ages. Either beavers c...

Chemical communication plays an integral role in social behavior by facilitating social encounters, allowing for
the evaluation of social partners, defining territories and advertising information such as species and sex.
Odors provide information about the social environment for rodents and other mammals; however, studies identifying
chemical compounds and their functions have thus far focused primarily on a few species. In addition, considerably
less attention has been focused on how environmental factors and behavioral context alter these
compounds during periods of reproductive quiescence. We examined the effects of photoperiod and social context
on chemical communication in the seasonally breeding Siberian hamster which displays modest territorial
aggression during long “summer-like” days, but increased aggression in short “winter-like” days. We collected
urine samples from long- and short-day male hamsters to investigate how photoperiod and subsequent changes
in reproductive phenotype alter urinary volatile compound profiles. Next, we identified changes in urinary compounds
before and after an aggressive encounter. Male hamsters exhibited a diverse urinary profile across photoperiods;
however, long-day reproductive males showed higher levels of individual compounds when
compared to short-day non-reproductive males. In addition, individual compounds were altered following an aggressive
encounter; some changed only in long days whereas others changed regardless of photoperiod. Further,
aggression and circulating levels of testosterone were positively correlated with urinary compounds in long-, but
not short-day males. These findings suggest both photoperiod- and aggression-specific physiological regulation
of urinary compounds in this species and contribute to a greater understanding of chemical communication more
broadly.

Premating behavior in the species Bombus confusus Schenck, 1859 was studied. The marking habits of bumblebee males were revealed and the use of their labial gland secretion in scent marks was proved chemically. Identical compounds were present both in the labial gland secretion and on male-marked objects. This chemical proof is reported for the first time from natural conditions of a B. confusus locality. Males' flight activities, site tenacity, and male–male interactions are described in detail. Contrary to literature reports, male B. confusus behavior does not basically differ from that of already known perching bumblebee species.

Abstract To advance our knowledge on the rubbing behavior of Andean bears (Tremarctos ornatus), we assessed characteristics of their rub-trees in the Peruvian tropical dry forest, where water is a rare and critical resource. We registered characteristics of rubbed and unrubbed trees and shrubs along bear trails in an area of approximately 100 km2 surrounding 7 waterholes in the western Andes foothills of Peru during austral summer 2014–2015. Analysis of 94 trees selected for rubbing (hereafter, rub-trees) and 253 available unmarked trees within a 5-m radius of each rub-tree showed that bears selected trees to rub that were relatively small and close to waterholes. Bears seemed to avoid the most common tree species, palo santo (Bursera graveolens), for tree-rubbing. We suggest that waterholes are important habitat features for Andean bears in the Peruvian dry forest, and that these sites be incorporated into conservation and land use management.

Lemur catta Troop D at Berenty Reserve has been studied intermittently for 35 years. During 90 hours of continuous sampling in August 1998, I observed and mapped troop movement and scent marking. I compared these observa-tions with data from June, 1975. The core of ...

Abstract. The two gerbils, Tatera indica and Meriones hurrianae, and the metad, Rattus meltada pallidior exhibit significant monthly variations in the dimension (maximum length X maximum breadth) of the ventral scent marking gland. Peaks in gland sizeoccur late in winter and ...

Behavioural changes associated with reproduction were studied in captive Newfoundland martens (Martes americana atrata), an endangered species. Patterns of scent-marking and behavioural interactions were recorded before and after a male was introduced to two females. After introduction of the male, marking by the receptive female increased, whereas the nonreceptive female marked less and became less active. Activity and marking bouts were significantly correlated throughout the day for the male and the receptive female, and they often marked in the same locations. The male marked more frequently when the receptive female was active and the female's marking was often associated with behavioural interactions. These findings suggest a major female influence on male marking and activity and suggest that marking may facilitate social interaction. In the spring following this study, the receptive female successfully whelped a litter, the first to be conceived and born in this captive ...