2023 Author: Bryan Walter | [email protected]. Last modified: 2023-05-21 22:24
American zoologists have observed strange behavior of gray foxes (Urocyon cinereoargenteus). Shortly after the cougar marked the territory, a gray fox appeared and rubbed its cheeks and neck against the spot where the cougar had left the mark. Scientists have suggested that foxes, "taking away" the smell of the cougar, thus scared away jackals or red lynx, which hunt foxes. The study is published in the Journal of Ethology.
Gray fox (Urocyon cinereoargenteus) in the Sierra Nevada
Animals use a variety of ways to define the boundaries of their territory. These can be audible or visual cues, such as howler monkeys or the red breasts of a robin, or smells. Most territorial mammals mark their sites with urine, feces, or a special secretion. Some mammals, such as marmots, rub against trees or the ground, leaving behind not only their own scent, but also their fur. By the tags, animals can not only understand that the "place is taken", but also find a partner during the mating season or find out that there is food nearby. According to the authors of the article, there are quite a few studies on the "communication" of individuals of the same species with the help of smells, but there are practically no works studying interspecific communication of this kind.
The authors of the new study decided to fill this gap. They studied the "communal" areas where predators of various species, including cougars and gray foxes, left marks. Scientists noticed that the foxes not only marked areas with urine, but also rubbed their cheeks and chin on the ground. According to the researchers, foxes in this way could either leave their scent and thereby communicate their presence to individuals of the opposite sex during the mating season, or warn potential rivals. According to another hypothesis, animals rubbed against places marked by the cougar in order to "collect" its smell, in order to scare away predators that hunt them, for example, a coyote or a red lynx.
The researchers installed motion-sensitive video cameras with infrared sensors in 26 “communal” sites and collected information over four years, from 2011 to 2015. They recorded the frequency and duration of visits, as well as the behavior of the foxes in the tagged plots left by cougars.
It turned out that foxes rubbed against the ground in about 10 percent of all visits (92 times out of 903). Moreover, in 85 percent of cases, they did it in the same place where the cougar left the mark. In addition, the researchers found a correlation between the behavior of the foxes and the freshness of the tags that the cougars left behind. The fresher the mark was, the more often the foxes “collected”, apparently, the still strong smell of a large predator. At the same time, foxes reacted differently to the tags of their species. They rubbed against the ground regardless of whether other foxes' marks were fresh or old. Interestingly, scientists recorded this unusual behavior of foxes throughout the year, regardless of the breeding season.
From these results, the scientists concluded that the main purpose of gray foxes when they “collected” the smell of cougars was to protect them from predators. Researchers speculate that coyotes or red lynxes may not attack gray foxes that smell like cougar at all. Or foxes can thus buy time to escape or to climb a tree (this behavior is considered the main avoidance strategy in gray foxes).
Other researchers offer an alternative explanation for this behavior. Steve Harris from the University of Bristol (UK), who studies foxes, believes that foxes mark territory with the help of saliva. "In my opinion, gray foxes leave their marks when exposed to the strong smell left by the cougar," says the scientist.
The authors of the article acknowledge that more research is needed for final conclusions, in which individuals of different sexes with sensors will take part, so that they can be monitored and that gray foxes are indeed using unusual tactics to scare away predators.
