Deer Biologist Speaks in Grand Lake Stream

October 17, 2014

 The Downeast Lakes Land Trust was pleased to welcome Inland Fisheries and Wildlife (IF&W) state deer biologist Kyle Ravana for an in-depth discussion of the herd’s population. “The million dollar questions is ‘How many deer do we have?’ and “How many deer statewide are we shooting for?'” said Ravana cutting   right to the chase.

Of course, that question, though simple, is surprisingly complex when considering the diversity of forest management approaches, variations in latitude,  altitude  and forest structures across Maine.  “We estimate that there are about 220,000 deer statewide. If we achieve the long term goals set during the last  planning  period, Maine would be home to approximately 378,000 white-tailed deer.” said Ravana

Managing for animal health, instead of density means that the  populations in the southern and food rich districts are growing, while less productive areas remain stubbornly below state targets. However, even knowing how many animals the landscape is capable of sustaining is a challenge, as looking at amounts of browse available is incredibly labor intensive, and expensive. “We look for indicators of the animal’s health, as undernourished bucks put less energy into antler growth, for instance.  Therefor by assessing the beam diameters of yearling bucks we can get a good idea about where we are in regard to the carrying capacity of the Wildlife Management District, as well as what the trends are.  When beam diameter goes down, we assume there is more pressure for the same food resource, thus the population has gone up,” explained Ravana.

Kyle graciously invited questions from the audience, and discussed issues such as supplemental feeding, over-wintering mortality, and predation. In regard to concerns that too many bucks are being taken, Ravana shared information from a study of winter road killed does. “While the sex ratio currently is 1.1 to 2.4 does to bucks, it’s important to keep in mind that bucks tend more than one doe in a season.  Our road kill study showed 96-100% of adult does in winter are pregnant. We can have up to 90% buck mortality and still be OK in terms of getting the does bred.  Currently we estimate buck mortality is at 49%.”

The DLLT regularly hosts speakers, work parties,  workshops, and leads outdoor adventures that highlight the natural and cultural history of the Maine woods and waters.  Visit our website to discover what is happening next!