Beaver Management Options on Washington CREP Sites
From the Ellensburg CREP Meeting April 25, 2013
Background
Prior to the first wave of trapping in the 1700s, beaver populations and
associated wetland complexes were likely common throughout much of the
floodplains in Washington State. By the late 1800s, the beaver population was
greatly reduced due to unregulated trapping (WDFW 2013). Populations started
to recover in the 1900s, but were kept at reasonable levels mostly by sport and
commercial trappers (Frank Corey, Whatcom Conservation District, personal
communication). By 1999, pelt prices fell to around $5.00/ pelt, reducing the
incentive for trapping. In 2000, the trapping initiative passed in Washington
State, which banned body gripping traps, again reducing trapping activity.
As a result, beaver populations have increased dramatically in recent years.
There are few natural predators and now little human predation. Although
beavers do take advantage of habitat improved by CREP and other programs
the beaver populations have increased much faster than the habitat improved.
The key point is that we have only planted a small percentage of streams and
beaver populations have increased dramatically everywhere.
As CREP projects increase in number and age, beaver activity on these sites has
also increased. Often, beaver activity is welcome or at least tolerated, but in
some instances damage occurs on farmland or neighboring property that needs
to be addressed. This paper seeks to provide guidance to conservation districts
and the Farm Service Agency on responding to landowner concerns about
beaver activity associated with CREP. Included are four sections; Part 1: Beaver
management Options and Costs, Part 2: Frequently Asked Questions, Part 3
Different Aspects of Beaver Habitat and Part 4: The State CREP Maintenance
Policy regarding beaver protection.
Beaver Management Options
Table 1 lists a structured approach that Conservation Districts can take to
address beaver issues on CREP sites. Beaver are generally desirable for stream
health, and when beaver populations are not overly problematic, landowners
should be encouraged to recognize the benefits of beaver to salmon habitat.
However, extensive damage to CREP sites, damage to neighboring land, or loss
of land are situations that require intervention. The type of response depends
upon the severity of the situation. Table 1 clarifies a set of appropriate
responses to varying situations and impacts.
Each of these responses has costs, and these are estimated in Table 2 for
consideration of mid-term management funding.
Table 1. CREP Beaver Management Options
Impact
Situation
Response
Low
Beaver browsing CREP willows & cottonwoods but they are resprouting
vigorously, not likely to impact CREP stocking levels now or in the future.
Monitor CREP stocking
during first 5 years.
Low
Beaver dam & flooding on site but flooding is limited to channel or valleys
Monitor flooding during first
that can accommodate higher water levels without losing many CREP
5 years.
trees.
Low
Beaver browsing and flooding more extensive but impacts are in wetland
Discuss benefits of beaver
areas that do not affect surrounding landowners and CREP participant is in
with landowners.
favor of beaver presence.
Beaver browsing CREP willows & cottonwoods but due to heavy reed
canary grass competition and seasonal high water levels, they are not
resprouting vigorously, not providing shade to channel.
Consider beaver cages,
fencing, high density
planting and plant species
selection, or a repellent
product such as Plantskydd
applied at temps warmer
than 50F.
Beaver dam & flooding on site and flooding limited to the confines of the
CREP buffer. Mortality of some CREP trees occurring.
Monitor flooding during first
5 years. CREP species
selection should have been
appropriate to wetland soils
Beaver browsing taking out significant number of 4+ year old CREP
conifers.
Install beaver fencing,
cages, or repellent.
Beaver dam & flooding on site and flooding affecting adjacent cropland,
pasture or infrastructure.
Consider options in the
following order: 1) repellent
product, such as
Plantskyyd, 2) beaver
deceiver, 3) trapping, and
if necessary, 4) work with
local WDFW office to
remove dam
Medium
Medium
High
High
Educate landowner about
beaver biology, benefits
and options. Explain
Landowner or neighbors calling in to FSA & Conservation Commission with
current agency policy and
complaints.
options; direct back to
conservation district staff.
High
Table 2. CREP Beaver Management Costs
Cost
per
Unit Unit
Activity
Beaver Repellent
Beaver cages
Narrative
$4.00 acre
This assumes spray on 40% of plants,
planted at 300 stems/acre
$4.50 each
Cages not installed on every tree;
conifers are prioritized, trees in first 50 ft
from stream are prioritized, occasional
"group cage" installed around a cluster of
trees to allow establishment in heavy
reed canary grass areas.
Works well on sites that have
channelized stream and/or topography
$3.00 lineal foot that favors a fence line.
Beaver fencing
Typical CREP site
needs
recent example - 5.7
acre project, 200 cages
required=$900 total
cost (200 trees
protected)
recent example - 28.8
acre project required
4890 lineal ft of
fencing=$14,670 total
cost (9000 trees
protected)
Beaver deceiver
$670 each
HPA required. Materials & Installation
$350 plus SEPA permit fee $320 (only
one SEPA fee per site).
Beaver trapping
$200 beaver
Trapping costs are usually per beaver but Two to six beavers per
some trappers charge per hour.
year.
One beaver deceiver
per problem dam.
High Density Planting strip $3,000 acre
1100 stems per acre, includes planting,
tubes and plants.
Depends upon project
size.
Species Selection
Costs covered in CREP installation,
Depends upon project
species selected that are least palatable size and zones of
to beaver.
beaver impact.
Frequently Asked Questions posed by CREP landowners
1.
Will FSA determine that I have violated my CRP-1 contract if
beaver have removed CREP trees?
Because CREP is a program that promotes wildlife, beaver are expected to utilize
the enrolled area. FSA will not determine that the CRP-1 has been violated due to
a wildlife issue. Landowners should be encouraged to communicate with FSA
regarding their wildlife issues, as FSA is willing to work with landowners on a
case-by-case basis to ensure the success of their CREP buffers.
2.
Will FSA reduce my annual rental payment if flooding has caused a
reduction of land occupied by CREP trees?
CREP acreage reductions occur when the soil itself has washed away such as
along the mainstem of a river. Beaver induced flooding is rarely permanent; it
fluctuates seasonally and across the flooded landscape.
3.
4.
5.
How can I reduce the flooding on my adjacent farmland?
How can I reduce the flooding on my neighbor’s adjacent farmland?
How can I reduce the flood damage to my roadway/infrastructure?
There are ways to control water levels in beaver ponds and still keep the beavers.
For example, a beaver deceiver is a cage or rack around the end of a culvert or
pipe to discourage the beavers from plugging the culvert. A pond leveler can be
installed to regulate the water level after a dam is constructed.
These devices are tricky to install and are best done by someone with experience.
They require a permit from the State Department of Fish and Wildlife.
6.
How can I protect my CREP trees & shrubs?
Exclusion: Fences along a watercourse or surrounding individual trees. May be
covered under CREP maintenance with the approval of an increased
CREP maintenance budget cap.
Plant Selection: Planting trees and shrubs as “sacrifice” areas to protect other
trees/shrubs. Planting trees & shrub species that beaver will avoid or
feed on a limited basis such as Oregon ash, cascara and red alder. Highdensity plantings are on 1 to 3 ft spacing in the first 20 ft from the stream,
utilizing willow, cottonwood, red-stemmed dogwood, twinberry or
ninebark.
Spray a repellent such as “Plant Skydd” on the base of the trees and shrubs.
The repellent smells like a predator. This was used on a CREP site as a
deer repellent and an unintended result was the beaver left the site for
one season.
Trapping: This is a short-term solution because new individuals quickly move
back in to vacated habitat. Typical trapping costs are well beyond the
CREP maintenance budget hold down. See the “Beaver Control Options”
by Carol Smith below for regulations regarding trapping.
7.
What assistance is available to help me control beaver damage?
a. Is there a potential for cost share assistance from FSA mid-term
management? FSA will pay cost share for mid-term management items
such that include limited beaver management activities such as beaver
fencing or cages around individual trees. If funds are available, state
money can be used to pay for the remaining 50% if approved by the CREP
program manager. FSA will not pay for instream structures, such as
beaver deceivers. The state might pay for these if approved by the CREP
program manager.
b. If beaver flooding is threatening public roadways, contact your county or
state road crews and they may send out a trapper.
c. If beaver flooding is threatening cropland and you are in a drainage district,
contact your drainage district commissioner and they may send out a
trapper for a reduced fee.
Different Aspects of Beaver Habitat
Positive:
 Salmon have co-evolved with beaver in the waterways. The pools created
by beaver dams are ideal for salmon resting and rearing. Adult salmon
can cross over beaver dams during high flows and salmon fry can
penetrate through cracks in the dam.
 Beaver dams are nature’s water storage devices and contribute to the
health of the watershed by keeping water in the system longer and
increasing summer flows. The dams increase the waterway’s ability to
absorb stormwater and reduce flood severity. Beaver ponds can function
like water treatment sites, allowing sediments and pollutants to be filtered
out of the watercourse and improving water quality. Beaver ponds store
carbon within their plant communities and thus reduce global warming.
 Many other wildlife species utilize beaver flooded areas. In most cases,
flooding caused by beaver damming sites is not a threat to the
functionality of the riparian forest buffer. If anticipated, planting and
species selection should allow the transition to a wetter hydrology, which
would be natural for the site. Areas affected by beaver are often limited to
the CREP project boundaries.
 Beaver activity is highest in the spring and late fall. Other times of the
year, beaver damage is not significant.
Negative:
 Beaver harvest of trees and shrubs for a food source or for dam building
reduces the stocking of the CREP buffer. Beaver prefer cottonwood and
willow but will rapidly deplete an area of planted cedars and Douglas fir
and have even taken out Sitka spruce.
 Their dam building can change hydrology and kill trees & shrubs that
require dry soil. Flooding can extend beyond the boundaries of the CREP
project. This can harm crops belonging to the cooperator or their
neighbor.
 Beaver induced flooding in cropland has the potential to carry applied
nutrients off the cropland and into the watercourse. Potential damage to
infrastructure includes erosion around a stream crossing, flood water overtopping a road crossing, water levels flooding farm or residential buildings,
or contaminated heavy use areas.
The State CREP Maintenance Policy Regarding Beaver Protection
The Washington Conservation Commission CREP maintenance policy currently
reads as follows:
“Where beaver activity is harming the CREP project or the adjoining landowner,
then the CREP resource specialists may develop a beaver management plan.
The plan will:
 Identify potential control measures;
 Provide a budget to install and maintain;

Discuss how and why the recommendation was formulated.”
In addition, the following is an excerpt of the Maintenance Guidelines, which
were adopted by WCD in December 2006:
o Anticipate change in hydrology due to beaver activity
 Look at soils & topography
 Assess potential impact to project and adjoining
landowners,
 If high
 Discuss with landowner,
 Encourage mitigation measures such as:
o Site de-leveling (Creating hummocks)
o Making provisions for beaver deceivers;
 Rationale:
o Reduce potential for conflicts with
adjacent land uses
o Ensure potential for tree and shrub
success.
o Protect against beaver predation:
 Plant wetland trees and shrubs that generally recover
from beaver damage within first 50’ of watercourse.
(For e.g. Oregon ash, Sitka spruce, willow).
 Install fencing
 Where likely to be effective in controlling
beaver access; and
 Where seasonal flooding does not submerge
the fence.
 Rationale:
 Beaver predation is generally limited to narrow
corridor.
 Fencing is expensive. So, use should be
judiciously applied to achieve goal and avoid
destruction.
During planning, CREP Technicians assess the site to answer the following
questions:
How long have beaver been at the site?
Where are they lodging?
Are they building dams?
What is their preferred food at this site?
Where are the low points of the project site; where will water end up when beaver
flooding occurs?
Is seasonal flooding compounding the problem for CREP seedling establishment
at this site? Is shading the channel to remove reed canary grass an achievable
goal if beaver browse is controlled?
Legal Issues from WDFW Regarding Beaver Control Options (personal
communication between Carol Smith (WSCC) and Sean Carrell (WDFW
Enforcement)
There are three major options for directly dealing with beaver. All of these apply
to private lands and private landowners. If public land is involved, the situation is
more restricted unless nearby private land is threatened. Here are the options for
private landowners.
1) Whenever damage to private land or property occurs, the landowner may
live trap the beaver with no permit or contact needed. However, if the landowner
is not trained as a certified nuisance wildlife trapper, the animal cannot be moved
and released somewhere else. It must be euthanized. The recommended
methods for euthanasia are available in a separate document.
2) A landowner may also use a body gripping trap (instant kill) if they have a
permit. The permit can be obtained from WDFW, and is free. It lasts 30 days and
can be renewed. The landowner will be asked to provide some sort of
documentation for any one of the following situations: property damage, risk to
human safety, risk to livestock or pets, timber loss, risk to ESA listed species, or
research. Only one of these is needed to justify the permit.
3) The landowner or management agent may hire a certified nuisance wildlife
trapper, who is then able to either live trap and move the animal or use a bodygripping trap. If a dam needs to be disassembled, the local WDFW habitat
biologist should be contacted first. Usually in cases of risk to property or safety,
dam removal is allowed.