Tuesday, May 27, 2014

The Family Life Of Adirondack Black Bears

Black Bear NYS Museum Camera TrapPriorities! Just like humans, some forms of wildlife are faced with the dilemma of not having enough time during the day to deal with all the issues that confront them. Over the course of the next several weeks, many black bears in the Adirondacks temporarily elect to put their nagging appetite on hold and channel the vast majority of their time and energy into finding a mate and winning the affection of a potential breeding partner.

In winter, the black bear experiences a profound state of dormancy in which many individuals lose from 15% to 20%, or more, of their autumn body weight. Once they emerge from their den in spring, the intake of food becomes a primary priority. As fiddleheads push upward from the forest floor, invertebrate activity begins to surge and populations of amphibians are moving to and from seasonal pools of water, this massive mammal attempts to regain a portion of its lost weight. However, despite the abundance of tender greenery, bugs and small ground critters, many black bears put their desire to eat on pause following the Memorial Day weekend, as a developing drive to mate overtakes this animal’s urge to eat.

During the last weeks of spring, most adult black bears begin to greatly increase the distance they travel, however finding food is not their main focus. The black bear has an exceptionally keen sense of smell, and its primary goal now becomes locating other bears. Each individual gives off it own unique scent, and as the animal travels, it periodically establishes scent posts to call attention to its presence. The most prominent scent post is made by a black bear when it stands on its hind legs and rubs its back against a sizeable tree along a game trail. A male traveling through the area can quickly detect such a “calling card” and identify, from the scents on and around the tree, the animal responsible for a specific scent post. If it should be a rival male, a confrontation is likely to occur, as older males do not tolerate other males in their territory. However, if a male detects the scent of a female nearing her heat period, he will follow her scent trail as long as necessary to catch up with the sow.

Yet, not all adult bears are on the move at this time of year. Sows that gave birth this past winter, and now have young cubs in their care, tend to confine their movements to relatively small areas, especially those in which food is plentiful. These females are extremely protective of their young and aggressively drive away any males that happen to cross their path. Since a sow’s cubs are in her care for the following winter, she does not come into heat the same year that she gave birth. Females with yearling cubs, however, instinctively drive these young bears away at this time of year as hormonal changes begin to occur within their body, awakening their reproductive desires.

As a bear wanders across its expanded territory at this time of year, it may periodically stop to eat, should it stumble upon a good source of food. However, if a male is on the scent trail of a female, he may simple pass by the area without stopping. Because of the much greater distances traveled by bears during these next several weeks, a bear can lose an additional amount of its already depleted body weight. In some cases, older males that must fight numerous rivals, and chase after females, have been known to lose as much as 10 to 15% of their weight over the next several weeks to month span of time.

When a male encounters a female nearing her heat period, he will first attempt to get her to accept him as a potential breeding partner and then remain with her for up to a week until she becomes fertile. Researchers that have studied bear breeding behavior in the wilds have noted that the pair engage in numerous, brief reproductive encounters lasting only a few minutes for several days after accepting each other. The two then have a much longer session that is said to last for well over a half hour. Some researchers believe that the sow needs to be induced into ovulating her eggs by such a prolonged reproductive bout, as do a few other forms of wildlife.

Afterwards, the two individuals gradually drift apart, with the nearly exhausted male going in search of other potential mates, and the female returning to a prime feeding site. It is known that the female may breed again with another male, however, she often chases away potential suitors that she later encounters.

As a rule, bears in the Adirondacks are very aware of the presence of a human nearby and avoid people at all costs. At this time of year, bears are especially alert to outside scents in their immediate vicinity. It is always wise to stay a long distance away from a sow with cubs, and at this time of year, it is also wise to keep your distance from a bear that is moving rapidly through the forest with its nose to the ground. And two adult bears seen lounging near one another should never be watched, as they may frown on the invasion of their privacy.

Photo of Black Bears in the Adirondacks from a NYS Museum Camera Trap.

 


Tom Kalinowski

Tom Kalinowski is an avid outdoor enthusiast who taught field biology and ecology at Saranac Lake High School for 33 years. He has written numerous articles on natural history for Adirondack Life, The Conservationist, and Adirondack Explorer magazines and a weekly nature column for the Lake Placid News. In addition, Tom’s books, An Adirondack Almanac, and his most recent work entitled Adirondack Nature Notes, focuses on various events that occur among the region’s flora and fauna during very specific times of the calendar year. He also spends time photographing wildlife. Tom’s pictures have appeared in various publications across the New York State.




One Response

  1. Lily says:

    Thanks Tom for another informative and interesting article about our Adirondack neighbors!