Maine's Black Bear Monitoring Program

The Maine Department of Inland Fisheries and Wildlife (MDIFW) is charged with managing Maine's abundant wildlife resources. One of our most celebrated and treasured animals is the black bear. Although many people enjoy an abundant bear population, too many bears can create problems for the bears and the people who live with them. Black bear management is a balancing act between maintaining a healthy and abundant population for all to enjoy, and limiting the growth of the bear population so that bear nuisance problems do not cross the line of public tolerance. A big part of managing bear nuisance problems involves modifying human behavior to lessen the number of negative bear/human interactions. This may include advice on taking in bird feeders, handling outside trash, and how to prevent damage to agricultural crops. Each fall, bear hunters enter the Maine woods in hopes of harvesting a black bear. These hunters and the rules that control their methods are the tools that managers use to ensure the bear population is not overharvested and to keep the bear population from "crossing the line".

How do biologists determine the proper number of animals that needs to be harvested? The first part of any management program is to have clear goals and objectives. Our management goals and objectives are set by interested members of the public that have reviewed and discussed the latest MDIFW bear assessment (Public Working Group). These goals are set about every 15 years. Our current management goal for bears is to provide hunting, trapping, and viewing opportunity for bears. Our population objective is to stabilize the bear population (no significant increase or decrease in numbers) through traditional hunting and trapping activities. In order to maintain a stable bear population, we must have a good understanding of the number of bears entering the population (recruitment) to replace losses. While the number of bears harvested by hunters each year is known, the number dying from other causes and the numbers entering the population must be determined by our research.

The Maine black bear monitoring program is a long-term project designed to continually gather data regarding the status of our bear population. The program began as a study in 1975 when Roy Hugie in cooperation with the Department established 2 study areas consisting of 4 townships each - Spectacle Pond (20 miles West of Ashland) and Stacyville (near Patten). Roy compared population characteristics of the bears living in these 2 study areas for his PhD. At that time, the Spectacle Pond area was lightly hunted; whereas, bears in the Stacyville area experienced heavy hunting pressure. Today, hunting pressure is more evenly distributed across the bears' range in Maine.

In 1981, the Department of Inland Fisheries and Wildlife took over Roy's project and established a new study area near Bradford (north of Old Town) in 1982. The Department also changed the focus of the project by using radiocollared females in each study area to represent bears across the state that are living in similar habitat conditions to that study area. For example, if we found that our radiocollared females in our study area in the northern commercial forest were particularly successful in raising their cubs in a given year, then we would assume that other females living in the northern commercial forest were also very successful.

Currently, we have three active study areas in northern, north-central and eastern Maine. In 2004, the Stacyville study area was discontinued and a new study area was created in Downeast Maine (northeast of Beddington). This study area was established to address a longstanding need to better represent a portion of Maine's bear population in eastern Maine living under habitat conditions not well represented by the other 2 existing study areas.

A total of between 75 and 100 radiocollared female bears are monitored each year in all three study areas combined. Radiocollars are helpful for monitoring black bears because their secretive nature makes them difficult to observe. Radiocollars send out a signal revealing each bear's location in her den as she hibernates under the winter snow. All of our collared female bears are visited each winter in their dens, which allows us to determine the number of cubs born. Because these cubs stay with their mother for 16 months and den with her the following winter, we can also determine how many cubs survive to one year of age (known as yearlings). We tag the ears of all cubs and yearlings to identify them. Female yearlings are equipped with radiocollars, which allow us to follow them throughout their lives after leaving their mothers the following summer.

We have found marked differences in reproduction, survival, and recruitment between study areas as well as within study areas over time while habitat and weather conditions change. The variables that cause these differences are many and complicated and are not easy to predict, measure, or even identify. Nutrition plays a major role in determining the number of cubs that are produced, and cub survival through their first year.

Bears in Maine utilize a wide assortment of natural foods, and the food types that are available in each study area are quite different. Traditionally, beechnut production has been linked to cub production in northern Maine, but these nuts have been less reliable in recent years and are less important in southern areas. The abundance of many types of bear foods are affected by weather, which makes predicting the food supply and cub production difficult from year-to-year. Closely tracking food production would help us explain year-to-year variations in cub production and survival. With limited funding, we can more efficiently measure cub production and survival directly during our winter den visits.

Forestry practices are continually evolving, which changes the world the bears live in and the food they depend on. Forestland ownership and market conditions are constantly changing as well, which also impacts forest resource management. Unforseen disease or insect outbreaks may influence forest composition and harvest strategies in the future. Thus, the general nature of the forests of northern Maine and the bear foods they provide are very different now than they were years ago, and most likely will be different in years to come. The combined effects of all these complex variables on bears are most easily measured by continually monitoring the bears' successes and failures directly in their dens.

A large part of our bear monitoring program involves trapping and radiocollaring bears in late spring and early summer. Trapping bears with foot-snares allows us to collar new bears to replace collared bears that have died or that have been lost due to malfunctioning collars. Periodic trapping efforts are necessary to maintain a representative sample of bears in each study area. We ear-tag many males while trapping and in the dens as well. Because males often damage their ears while fighting, we also tattoo their inner lip for a permanent mark. These marked males offer additional information regarding their movements and mortality when they are re-encountered through hunter harvest, roadkill or our own trapping efforts.

We have learned a lot about bears in Maine over the last 35 years, but we are still discovering new things. Each field season of data collection still reveals unexpected surprises. The Department's bear monitoring program is an ongoing source of information providing biologists with the information necessary to properly manage this valuable wildlife resource. It is "our finger on the pulse of the bear population".

This work is possible thanks to a federal tax on firearms, ammunition and other hunting related items. The funds from this federal tax (known as Pittman-Robertson funds) pay for about 75% of the cost of the program. The remaining 25% comes primarily from hunting and fishing license sales.

To help out Maine's Black Bears and their Research and Management, consider joining the Maine Black Bear Stewardship Committee: Contact Melissa Majkut: 642-6044 or Melissa.Majkut@Maine.edu Thanks!

DEPARTMENT INFORMATION

Maine's Black Bear Monitoring Program