Tifft Nature Preserve Management Plan - Buffalo Museum of Science

enefits and the habitat for other wildlife species that beaver impoundments create,
higher population goals were established and beaver numbers grew over the past
decades. In 1993, the DEC estimated there were about 17,500 active beaver colonies
in the state which exceeded the population goal by 25%. Currently, many state wildlife
management units are at or above their beaver management objectives and the
property damage from beavers is in the millions of dollars annually. At Tifft Nature
Preserve, beavers plug the culvert under Old Tifft Street and build dams in the small
stream flowing into Lake Kirsty. Beavers also create problems throughout the preserve
by felling or chewing on trees, including some rather large cottonwood trees. The
impact to the preserve’s trees is a particularly important long term issue to address
since there is little recruitment of young trees due to heavy browsing by the large deer
herd.
The exact size of the beaver population on the preserve is unknown, but signs of
beavers are widespread. There is evidence of beaver activity around Beth Pond, the
cattail marsh, and in the stream flowing into Lake Kirsty. A beaver family may reside in
each of these areas for a maximum of three beaver colonies on the preserve. In
Canada, the density of beaver colonies ranges from 0.33/km 2 in a population where
trapping occurred to a high of 3.51/km 2 where “nuisance beavers” were present, with an
average of 1.0-1.2/km 2 (Müller-Schwarze and Sun 2003). The preserve is 1.1 km 2 ,
which would allow only one colony of beavers on the preserve to remain with natural
population levels. The average colony in western New York is four beavers, but can
reach as high as ten. A colony or family consists of two adults, two young of the year
(on average), and occasionally two or more yearlings which tend to remain with the
family when population densities are high and there are no vacant territories to disperse
into (Müller-Schwarze and Sun 2003). Assuming all three areas with beaver activity
each contain one colony, a population of between 12 and 30 beavers is a rough
estimate for the preserve.
Options for Preventing Beaver Damage
Beaver damage is common throughout the state and the NYS DEC has
developed a Nuisance Beaver Control Techniques Manual (http://www.dec.ny.gov/
animals/6992.html) to assist landowners in minimizing damage and conflicts. Potential
options presented in this manual will be outlined with their applicability at Tifft Nature
Preserve addressed. The beaver is a protected furbearer species and therefore all
control of nuisance beaver or disturbance to their den or dam requires a permit under
Article 11 of the New York State Environmental Conservation Law.
Protecting Trees and Shrubs – Individual trees and shrubs can be protected by
loosely wrapping to a minimum height of 3 feet (1 meter) with welded wire fencing,
chicken wire, or roofing felt loose enough to allow for growth. Fencing may still leave
some trees vulnerable to damage if beavers are active during deep snow. Fencing
must be installed before serious damage to a tree occurs since a tree that is girdled
(gnawed all the way around), but not felled, will still die. Many trees on the preserve
have already been wrapped with chicken wire and successfully protected from damage.
Tifft Nature Preserve Management Plan 35