Didn’t get an any-deer permit, or didn’t get one for their preferred wildlife management district? You’re not alone. The reasons are numerous and varied but there’s one overriding factor, and given pending proposals, the situation is likely to get worse. Let me explain.

Carrying capacity (K) is the number or density of a particular species an area can support without deleterious effects on the animals or their habitat. For decades, state wildlife agencies established deer populations objectives based on K. In most cases they were trying to build the herds. When that goal was accomplished, objectives shifted toward maintaining the herds somewhere around what the land can support.

“Conservation” means wise use. That in turn means managing deer populations at a level that can support a certain harvest of surplus animals indefinitely. Biologists call this “sustained yield.” For reasons too complicated to explain here, maximum sustained yield (MSY) or the highest harvest a deer population can perpetually support occurs when the population is around 50 percent of K.

But hunters don’t want to just kill deer. They want to enjoy a positive experience in the process of procuring protein. Renowned whitetail authority Dr. James Kroll refers to this population density that best maximizes both deer harvest and hunter satisfaction as optimum sustained yield (OSY) and says it occurs at 60 to 70 percent of K. From a purely biological perspective, this should be the population objective.

But wildlife like deer are public property, held in trust by state wildlife agencies to be managed for all citizens. Within those state agencies, and above the biologists, are planners and managers. As our nation’s deer herds reached, then began exceeding biological population objectives, planners and managers found themselves facing new challenges, like car-deer collisions, crop depredation and damage to ornamental shrubbery of wealthier and more outspoken citizens. So they developed an artificial construct called social or cultural carrying capacity (CC) – a deer population density that the general non-hunting public can withstand/support. Not surprisingly, it’s well below K, and even OSY. And that’s been the objective level in Maine for a couple of decades.

Nearly two decades ago, when deer herds were starting to exceed objectives, I sat down with Gerry Lavigne, Maine’s deer biologist at the time, to discuss the state’s herd. He said, “Populations in some of the problem areas are at, or approaching 30 to 40 deer per square mile.”

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He also said this is still around 50 percent of K (and well below the 70 percent level recommended by Kroll). In other words, some areas (central and southern Maine) could support between 40 to 60 deer per square mile with no deleterious effects on the natural habitat, and would be well within the limits biologists strive for under the precepts of sound deer management. But then current management objectives for those areas were 15 to 20 deer per square mile. As a side note, the predicted harvest for that year (2001) was 32,850 deer.

Roughly a decade later I spoke with then deer project leader Lee Kantar. He acknowledged that the state had misinterpreted some of the data they use to determine the amount of any-deer permits issued. That resulted in an overharvest of does in southern and central Maine for a couple seasons, and in turn populations were even further below objectives.

After several devastating winters took a heavy toll on Maine’s deer herd, IFW put together “A Plan to Increase Maine’s Northern, Eastern, and Western Deer Herd.” A good concept initially, it ultimately amounted to little more than putting all the various existing management programs into one document. There were some lofty goals, particularly with regard to protecting winter habitat, but little if anything was done to reach them.

Now there’s a new plan. Every 15 years, IFW develops a long-term management plan for all our big-game species. A previous one called for a statewide deer population objective of 384,000. Dropping back to 2001 for a moment, Lavigne said, “If we can succeed in restoring winter habitat to the north and east, and solve the access problem, we can safely winter 480,000 deer and hold the harvest at 50,000 deer.” The target population goal in the most recently adopted big–game management plan is 210,000 animals by 2033. That’s roughly half of the previous objective and well below the OSY level. And it means even fewer any-deer permits in the future.

The most obvious solution to growing the herd is improving winter habitat, which can be a daunting task in a state where 90-some percent of the forested land is private. But state wildlife managers do have some significant opportunities they’re not exploiting.

IFW is responsible for management and maintenance of over 100,000 acres aggregated into 62 wildlife management areas. Currently, 92,000 acres of that is not managed for deer wintering areas. Meanwhile, the Bureau of Parks and Lands coordinates habitat management on another 600,000 acres of state lands, 571,000 acres of which is currently not managed for winter habitat.

Bob Humphrey is a freelance writer, registered Maine guide and certified wildlife biologist who lives in Pownal. He can be reached at:

bhhunt@maine.rr.com


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