Black Bears, Routine, and Human Interference
We often think of animals like bears as being big and threatening, a species that poses more of a danger to humans than we pose to them. In areas where black bears live in close proximity to humans, we may even occasionally hear news reports of them venturing into areas populated by humans. Such news stories may give us the impression that bears are encroaching into human areas, when in fact there may be other factors at play that are forcing them to venture into our living spaces. It is much more sensible to think that bears are going against their nature to forage for food where they may not actually want to.
A study from the journal Behavioural Processes looks at how the edges of human and bear habitats press up against each other, and how black bears, as a top predator alter their foraging habits to, as much as possible, avoid human contact. Human activities, the researchers note, can disturb wildlife and “result in a behavioural response similar to predator avoidance.” They note that large carnivores like the black bear are typically hunted by humans and have “no other predators which might influence their behaviour.” For bears in particular, past studies have shown that paved areas tended to alter bear paths, and that female bears with cubs tended to select habitats with lower highway densities. To better understand just how much black bears alter their behavior based on human interaction, researchers “studied movement behaviour of radio collared black bears in the Upper Peninsula of Michigan, USA using distance to roads and road crossing frequency during the hunting season as a proxy for disturbance avoidance behaviour.”
What they observed was a set of behaviors that show that the movements of large carnivores, black bears in particular, alter their behavior significantly:
(1) in periods without perceived disturbance the distance to road was indifferent, but crossing of paved roads was low; (2) during periods with disturbance due to dog training and hunting with dogs, bears increased their distance from risky non-paved roads which resulted in decreased distance to less risky paved roads; (3) males were found closer to non-paved roads during dog training than females, but were further away during dog hunting; (4) bears increased the number of crossings of both road types during a higher risk time period and bears crossed both road types more frequently at night.
Though the frequency of road crossings was “lower than expected” the above observations show a change in behaviour that makes black bears, a top predator, behave more like prey. “Even top predators such as black bears,” say researchers, can distinguish between fine scale variations in disturbance and adjust their behaviour spatially and temporally to avoid disturbance,” which is a behavior most commonly displayed by non-predator species. It shows that humans can incite behavioral changes in animals that sit at the highest trophic levels, and it is something we should keep in mind as we assess our actions around and towards these species.
Though it many be difficult to advocate on behalf of large carnivores such as black bears – they are not generally thought of by the public as animals that need our help – this study demonstrates that they can be just as vulnerable to disturbance as prey species can be. The sensitivity of black bears to the movements of humans should give us pause; every time we see a story where bears have ventured into human areas, advocates should remind the public that these are not acts of aggression, but rather acts of desperation.