BI Monthly Article: An Observational Study of Coyote (Canis latrans) Scent-marking and Territoriality in Yellowstone National Park

An Observational Study of Coyote (Canis latrans) Scent-marking and Territoriality in Yellowstone National Park

Let’s further dig in to the olfactory senses of the canis latrans. We will pick up where we left off on the first article from “field evaluation of coyote attractants.

This research is a study of the role of scent-marking behavior (such as urine and feces marking) in territorial maintenance and defense in coyotes (Canis latrans). It is based on observations of individual animals and aims to examine patterns of scent-marking within coyote home ranges and territories. The study also aims to investigate the relationship between scent-marking and intrusions by neighboring coyotes, and to examine the role of social status and reproductive status in scent-marking behavior. The research suggests that scent-marking may serve multiple functions in coyotes, including territorial maintenance, social communication, and reproduction.

This research was conducted in the Lamar River Valley in Yellowstone National Park in Wyoming. Data was collected from January to May 1997 through direct observations, snow tracking, and radio telemetry. Individual coyotes were identified through physical characteristics and some were marked with ear tags and/or radio collars to aid in tracking their movements and understanding their scent-marking behavior. Data on each instance of scent-marking behavior was recorded, including the date and location, type of mark, posture used, identity of the marking animal, whether the mark appeared to be directed, if there was associated ground-scratching, and any unique circumstances. The location and movements of identified animals were also recorded to determine their home ranges. The data was analyzed to examine the distribution, density, orientation, relative frequency, demographics, and temporal variations of the scent marks. Polygons were constructed around the scent marks of each group, and Pearson's correlations were used to assess the relationship between territory size and group size.

Coyotes in the Lamar Valley in Yellowstone National Park engaged in five types of scent-marking behaviors: raised-leg urination (RLU), squat urination (SQU), forward-lean urination (FLU), defecation (DEF), and body rubbing. The relative frequency of these behaviors varied over the course of the study and was influenced by the season. The spatial distribution of the scent marks showed that they were typically found on the perimeter of the territory rather than evenly distributed throughout it. The frequency of RLU and FLU behaviors was higher on the perimeter, while the frequency of SQU behaviors was not significantly different from an even distribution. In one pack for which the gender and social status of all members was known, RLU behavior was associated with males and dominant individuals, while SQU behavior was associated with females. Scent-marking behaviors were also found to be directed towards specific landmarks or objects in some cases and were often accompanied by ground scratching. The frequency of ground scratching was highest in association with RLU behavior. Scent-marking behavior was also found to be influenced by the presence of other coyotes, with an increase in marking activity during times of intrusion by neighboring coyotes.

Approximately 50% of the coyotes' urine marking behaviors were directed towards a specific object or location, with the majority of these being made in succession by different animals. The most common objects of orientation were spots where another animal had marked previously, followed by carcasses or foraging locations. There was no significant difference in the proportion of directed-only marks in the interior versus the periphery of the territories, but there were significantly more marks in the periphery that were associated with ground scratching. Multiple marks were observed on 27 different occasions, with the majority of these being made in sequence by different animals. There was a higher number of multiple marks in the perimeter of the territories than would be expected by an even distribution.

Researchers observed five packs of coyotes in the Lamar Valley in Yellowstone National Park and collected data on their scent-marking behaviors. The researchers found that there was no overlap of scent marks between adjacent packs of coyotes, which suggests that scent-marking serves a territorial function. The density of marks was also higher in the periphery of the territories, and pack size was correlated with territory size. The coyotes also exhibited more directed and ground-scratching behavior in the perimeter of their territories. The researchers also found that scent-marking behavior was affected by season, with more marking occurring in spring. Overall, the findings of this study support the idea that scent-marking serves a territorial function in coyotes, helping to define and defend areas that contain important resources.

The present study found evidence of territorial function in scent-marking behaviors among coyotes in the Lamar Valley of Yellowstone National Park. The spatial distribution, density, temporal variation, demographic associations, and directional qualities of marks all support the idea that scent-marking serves as a mechanism for territory maintenance and defense. The study also found that scent-marking may serve as a means of communication about food and food caches, and may have a self-orientation function for individuals within their own territory. The mechanisms by which coyotes gather and process information from scent marks, as well as the specific types of information conveyed, are still unknown and require further research.