Beavers are considered a "cornerstone species" since they change the habitat
they live in like no other animal. Thanks to the Beaver, other species such as
turtles, frogs, birds, and fish can find a good home and enjoy naturally
created habitat. Naturally created wetlands help to cleanse the water and serve
as filters that are instrumental in getting rid of pollutants and silt. These
areas are a valuable means of irrigation and water control. Beavers take a
fitting niche in present day environment and do a perfect job.
However, economic and ecological values of the Beaver have been the subject of
much debate of late. With growing numbers of animals in practically every state
and province, damage caused by this rodent's activity seems to surpass its
value. Dams result in flooding which can be negative for forests, roads, and
agriculture. Beavers may damage fish and farm ponds and destroy agricultural
crops when feeding. A number of other dreadful effects caused by this species'
activities have aroused the need for managing Beavers and preventing them from
undesirable habitat changes.
When conflicts arise, working with the beaver is most often the best solution.
If beavers are removed from good habitat, others will normally move into the
empty habitat. Survivors respond with compensatory reproduction and beavers can
migrate over tens of miles. Allowing the beavers to remain while addressing the
specific problem (for example, flooded roads or tree cutting), also preserves
the many beaver benefits. By installing flow devices, often most of the beaver
wetlands can be saved, while ending the unwanted flooding. Problems with
objectionable tree cutting can often be solved with fencing or other methods.
Proven, cost-effective devices, such as beaver pipes in dams, are installed to
control objectionable flooding. Road flooding is a common beaver/human conflict
that be solved with methods such as "exclosures," "Beaver Bafflers" or Beaver
Deceivers. Since beavers are quite adaptable, it is best to use proven
If beavers must be relocated, using Hancock or Bailey live traps are the most
humane methods. Snares hold the victim helpless against predators and can cause
death by strangulation, or drowning due to entanglement. No kill trap that
currently exists will reliably cause an instant death under field conditions,
and drowning traps are especially inhumane for animals that can hold their
breath for 10 to 15 minutes. Like other wild species, surviving beavers respond
to persecution with larger litters. Besides being a temporary solution, removal
is often environmentally disruptive as it leads to the draining of beaver
wetlands when beavers are no longer present to repair dams.
How to Protect Trees from Beavers
Beavers often prefer to eat seaweed, clover and other herbaceous vegetation
during warm weather, instead of the green bark (cambium) of trees. But, in
areas with harsh winters, they normally need to prepare an underwater food
cache of branches. They also use peeled sticks to build their lodges, and dams.
Because one beaver family (colony) often builds several lodges, the number of
lodges is not a reliable way to estimate the population.
Beavers prefer fast-growing trees, such as poplar, willow, cottonwood and alder,
which normally have little commercial value. Although the felling of these
trees appears destructive, such pruning often results in more, bushier growth
in the spring. For example, each cut willow stem can lead to three to four new
stems. If the beavers then use the branches for a dam that creates a wetland,
great benefits can result, such as erosion abatement, flood control, water
cleansing and more biodiversity.
When it is desirable to protect trees from beaver felling, consider that most
cutting occurs within five yards of shore, and that the likelihood of damage
decreases as the distance from shore increases. Also, while beavers prefer
certain tree species, they do not necessarily take them in order of preference.
Leave the trees that are already down, while protecting others. When planting
trees along shorelines, consider less palatable varieties, such as spruces.
Cylindrical cages are the best way to protect valuable trees. Make them of
hardware cloth or sturdy 2 x 4 inch welded wire fencing, about four feet high
(three feet is adequate in areas without snow). Encircle the trunk, leaving a
space of about six inches between the tree and the fence. Cut every other
horizontal wire and bend into hooks to connect with the other side. Cages can
be anchored to the ground with stakes.
Turkey or chicken wire is less reliable, but it is sometimes used to protect
many small trees as, for example, with mitigation plantings. If this type of
wire is used, stake close to the trunk to prevent crushing by beavers.
Paint with Sand
A newer method to prevent beaver gnawing involves coating tree trunks with a
sand and paint mixture. Use 8 ounces of fine sand (30 mil, 70 mil or mason
sand) to one quart of oil or latex paint. Stir often and paint trunks about
four feet high. The paint can be clear or color-coded to match the trees. Avoid
painting young trees less than about six feet tall as this may be harmful.
Low fences can be used to protect groups of trees, and normally need not
surround the entire stand, since beavers dislike being separated from the
water. Have the fence fit tightly to the ground and trail each end toward the
water. Monitor often in the beginning for burrowing. If digging occurs, two
concrete blocks tied together can be used to block the tunnel.