Beaver management and control in Georgia / David Gregory, Greg Waters

Beaver Management And Control In Georgia
Georgia Department of Natural Resources Wildlife Resources Division Game Management Section

Sonny Perdue, Governor State of Georgia

Noel Holcomb Commissioner Georgia Department of Natural Resources
Dan Forster, Director Wildlife Resources Division

Board of Natural Resources

Loyce Turner Valdosta -- First District

Joe Hatfield Clarkesville -- Tenth District

Philip Watt

Bill Carruth, Vice-Chairman

Thomasville --Second District Hiram -- Eleventh District

Warren Budd, Jr. Newnan -- Third District

Mabel Jenkins Millen -- Twelfth District

J. David Allen Scottdale -- Fourth District

Walter A. Hudson Douglasville --Thirteenth District

Thomas Wheeler, Jr. Duluth -- Fifth District

Jenny Lynn Bradley,Secretary Savannah -- Coastal District

Jim Tysinger Atlanta -- Sixth District

Gene Bishop Dawsonville -- Member-at-large

Bob Rutland

Phyllis Johnson, Chairman

Covington -- Seventh District Hazlehurst -- Member-at-large

Earl Barrs Macon -- Eighth District

Bill Archer Tiger -- Member-at-large

Jim Walters Gainesville -- Ninth District

Ray Lambert, Jr. McDonough -- Member-at-large

Beaver Management And Control In Georgia

Georgia Department of Natural Resources Wildlife Resources Division Game Management Section

Authors: David Gregory, Wildlife Biologist Greg Waters, Senior Wildlife Biologist

Preface
This booklet is intended to provide general information on beavers in Georgia and to assist individuals or landowners experiencing beaver damage problems. The Wildlife Resources Division (WRD) hopes this booklet will serve as a quality source of information for handling nuisance beaver problems. If you need additional assistance with beaver nuisance abatement or other wildlife related issues, contact your local WRD office.

Game Management Offices

Region I

Armuchee

(706) 295-6041

Region II

Gainesville

(770) 535-5700

Region III

Thomson

(706) 595-4222

Region III

Thomson (Augusta) (706) 667-4672

Region IV

Fort Valley

(478) 825-6354

Region V

Albany

(229) 430-4254

Region VI

Fitzgerald

(229) 426-5267

Region VII Brunswick

(912) 262-3173

Headquarters

(770) 918-6416

Acknowledgements
We express appreciation to all the members of the 2002 Small Game Committee and Greg Balkcom for their valuable assistance reviewing and editing this booklet. Small Game Committee members (2002) included: Jerry Bearden, Lee Kennamer, Nick Nicholson, Steve Ruckel, George Steele, Jim Simmons, Reggie Thackston, Mark Whitney and Dan Forster. We also would like to thank Doug Hall and Doug Hoffman of the United States Department of Agriculture, Wildlife Services for their expert advice, edits and photography used in the booklet. Additionally, we would like to thank Melissa Cummings, Wildlife Resource Division Public Affairs Office for her valuable layout and printing assistance. Funding for the printing of this publication was provided by Forest Stewardship Program funds.

Table of Contents
Introduction ...................................................................... 1
Life History ....................................................................... 1 Physical Characteristics......................................... 1 Reproductive Characteristics and Social Structure 2 Feeding Habits ...................................................... 3 Lodges, Dens and Dams ...................................... 3 Distribution ............................................................ 4
Importance of Beavers ................................................... 4 Ecological ............................................................. 4 Economic .............................................................. 5
Damage Prevention and Control .................................... 5
Nonlethal Control Methods ............................................. 5 Fencing .................................................................. 6 Drainage Devices .................................................. 6 Repellents .............................................................. 8 Dam and Lodge Removal ...................................... 8
Lethal Control Methods ................................................... 8 Shooting ................................................................. 8 Trapping ................................................................. 9
Summary ........................................................................... 11

INTRODUCTION
Beavers (Castor canadensis) were once virtually eliminated from Georgia, as well as most of their range throughout the United States, primarily because of unregulated trapping and habitat loss. The Georgia Department of Natural Resources and the United States Fish and Wildlife Service responded to this loss and began a restoration program in the 1940's. The Piedmont National Wildlife Refuge, newly established at the time, was used as the first location to restock beavers. Following the success of this establishment, a statewide restocking effort was conducted from 1949-1959. During the last few years of this restoration program, Georgia was considered one of the leaders in beaver restoration. As the beaver population increased, new management regulations were established that allowed them to be harvested as a renewable resource for their fur.
Since demand and pelt prices for beaver have subsequently remained relatively low, beavers have thrived and are common statewide. Today, the trapping of beaver in Georgia is limited because of low prices, low fur demand and fewer trappers. In fact, beavers are quite abundant, little trapping pressure exists and there is no closed season on beavers in Georgia.
Beaver sitting creekside
LIFE HISTORY
Physical Characteristics Characterized as North America's largest rodent, beavers are large semi-aquat-
ic animals spending portions of their lives on both land and in water. Perhaps the most commonly recognized feature of beavers is their broad flat tail. While on land, they will use their tail for stability while sitting, feeding or chewing trees. In water, the tail serves as a warning device when slapped on the water to alert other beavers of danger and as a rudder for swimming.
1

Beavers have many other adaptations that make their lifestyle unique. The front feet are equipped with heavy toenails for dredging mud used in dam building, digging bank dens or handling food and construction material. The large webbed feet assist with swimming and stabilization while standing or walking on soft ground. The fourth toe on their hind feet has a double toenail that is used to comb fur and preen (distribute oil from oil glands to waterproof the fur). Their eyes are located near the top of their head allowing them to see above water while keeping most of their body submerged. Additionally, a thin transparent membrane covers their eyes allowing them to see quite well when submerged. The ears and nose have valves that close and keep out water when submerged. Finally, the lips on beavers are positioned to meet behind the incisor teeth, preventing water from entering their mouth and allowing them to chew while underwater.

Reproductive Characteristics

and Social Structure

Distinguishing between male

and female beavers is quite diffi-

cult without an actual physical

examination. Both sexes have a

single cloacal opening that is used

by both the reproductive and excre-

tory systems. The male organ is

actually contained inside the cloa-

cal opening. Beavers are social animals and

Adult beaver

usually live in family units called

colonies. A single colony may contain a breeding adult pair and both yearling and

juvenile offspring. Beavers usually mate for the life of an individual. If a mate

is killed, the remaining beaver will form a new breeding pair with another beaver.

Breeding in Georgia typically occurs in October through March. Offspring are

born 105-107 days following breeding. Beavers become sexually mature at two

years of age and will then produce one to four kits (young) annually. Once the

offspring reach sexual maturity, the young either leave to find their own territory

or are forced out by the adults.

Beavers are territorial animals. Male and female beavers produce scented oil

or castoneum from their castor glands that is used to mark territory and attract

mates. Leaves and mud are hauled out of nearby water to create a mound on

which castor is deposited to mark territory. Although castor mounds are built

year-round, increased mound building activity occurs during the winter and early

spring during times of dispersal and mating.

2

Feeding Habits

Beaver creating a meal out its

Beavers are one of the many

preferred winter food.

herbivores (plant-eaters) found in

Georgia. Their diet varies season-

ally. During the winter months,

woody vegetation is the meal of

choice. Preferred winter foods

include sweet gum, ash, willows,

poplar, cottonwoods, pines and

fruit trees. However, no tree is

safe when a beaver is hungry.

During the spring and summer,

beavers seem to depend less on

trees and relish aquatic plants and lush tender green shoots of terrestrial plants.

When available, beavers will eat green corn and use the stalks for dam building.

In preparation for winter, beavers may create a food cache or feed bed. Trees

are cut down and chewed into manageable sections and floated to the food cache.

These food storage areas are usually located underwater near winter dens for easy

access during times of harsh weather. In appearance, food caches will look like

brush piles located in the water but with all the bark chewed off the limbs.

However, food caches are not always built, especially in the south. Because win-

ters are typically milder than in the north, beavers will sometimes opt to survive

on whatever food is nearby their winter lodge.

Lodges, Dens and Dams Shelter is an essential component of any animal's habitat. Beavers create their
own shelter in the form of either bank dens or lodges. Dens are created by digging holes in banks of lakes, ponds, rivers, creeks or streams. Dens may collapse when flooded causing beavers to either move and create a new den or patch the holes in the existing den using mud and sticks. Beavers oftentimes will have a series of dens in case one den becomes unsuitable. If the banks are not suitable for digging, beavers will opt to pile up sticks and form a lodge. Entrances to either the den or lodge are positioned underwater but the den itself is usually located 1-2 feet above the water level.

Beaver lodge 3

One of the most famous character-

Beaver dam

istics of beavers is their ability to build

dams. Beaver dams have three pri-

mary functions. The first is to control

water levels to protect lodges and dens.

Dams help mediate flooding thereby

minimizing damage. The second func-

tion is protection. Beavers move more

efficiently in water and are able to

avoid predators more effectively. The

third, and most important, function is

to assist them in feeding. Beaver dams

back up water and flood vegetation to

create ponds, which allows beavers to

feed in an aquatic environment. Plus,

it is easier to float sticks in water than to drag them on land.

Distribution Beavers can be found throughout Georgia and most of North America wher-
ever suitable habitat exists. Present in most areas with a year-round water flow, beavers are found in streams, lakes, farm ponds, wetlands, and low lying land or swamps along flood-prone creek and river bottoms. Beavers occasionally are found in roadside ditches, drainage ditches, and sewage ponds and are becoming more common in urban areas.

IMPORTANCE OF BEAVERS

Ecological

From an ecological standpoint,

beavers are one of the most impor-

tant animals in Georgia. Other than

man, no animal makes such dramatic

landscape changes to the habitat in Beaver ponds provide excellent habitat

which they live. Ponds created from

for a host of wildlife species.

beaver dams provide excellent wetland habitat for numerous plants and animals.

Beaver ponds are critical habitat for many species of waterfowl and other migra-

tory birds.

Landowners benefit from having beaver ponds on their property in the form of

additional hunting, fishing and bird watching opportunities. Beaver ponds are

useful for irrigation, flood control and help maintain water tables during droughts.

Beaver ponds also act as a natural filtration system, removing silt and other impu-

rities from water.

4

Economic

Historically, beavers had a positive impact on the economy and were the most

widely and intensively sought natural resource in North America during the

1700's and 1800's. Their fur was used for clothing, especially hats in Europe dur-

ing the 1800's. Oil from their castor glands was an essential component in many

high quality perfumes. Beaver coats and other garments were extremely desirable

throughout much of North America.

Today, beavers remain one of the most valued fur sources, yet prices remain

relatively low, especially in Georgia. Southern furs are considered poor quality

when compared to furs from the North. However, beavers are still desirable for

coats, hats and other outer garments and their castor glands are marketable for use

in the lure or perfume industry.

In recent times, beavers are considered by some to have more negative eco-

nomic impacts than positive.

Flooding caused by dams may result

in damaged timber, crops or pasture.

Highway departments may spend

thousands of dollars every year

attempting to clear beaver plugged

culverts or paying trappers for nui-

sance beaver removal. When feeding,

beavers girdle and destroy trees and

shrubs, some of which are highly valued and expensive. Beavers will feed on agricultural crops, especially corn

Highway department unclogging a culvert plugged by beavers

and soybeans, resulting in diminished yields for the farmer. Beavers often may

damage fish and farm ponds through den and dam construction.

DAMAGE PREVENTION AND CONTROL

Beauty is in the eye of the beholder when it comes to beaver damage situations. One individual may gain happiness and satisfaction seeing beaver ponds with chewed trees on their property and knowing that wildlife is alive and flourishing on the land. Others may find displeasure seeing flooded land with damaged or dead trees (although it is important to remember that even dead trees can provide valuable habitat to certain wildlife species). Individuals having problems due to flooding, damaged crops, trees or landscaping may want beavers removed from their property.

NONLETHAL METHODS If you don't mind having beavers on your property but don't want the nuisance
problems associated with beavers, there are several options.
5

Fencing If you have a small area of trees or plants to protect, a perimeter fence may be
the best choice. Constructing a rigid fence or an electric fence along the shoreline or perimeter of the area to be protected will exclude beavers. The bottom of a rigid fence should be buried into the ground while the top of the fence is at least 3-feet high. An electric fence should be placed approximately 8-10 inches off the ground. A perimeter fence also will help with other chewing problems like those caused by rabbits, rats and mice.
Fencing may be an appropriate solution when beavers are plugging up drainpipes and culverts. Using #6 gauge cement reinforcing wire mesh staked in a rounded fashion well into the ground at a distance beyond the end of the drainpipe will discourage beavers from plugging up the drain pipe directly. However beavers may just build up against the fence and still cause flooding problems. The addition of a drainage device incorporated in the fence will provide continued water control even with a dam built up against the fence.
Wire fencing certainly is the most efficient method to protect individual trees. A rigid welded wire fence using a 2x4-inch mesh or smaller or -inch hardware cloth is often effective in preventing beaver damage. Wrap the fence around the base of the tree with the bottom firmly staked to the ground and the top of the fence at least 3-feet high. Be sure to leave 2-3 inches between the tree and the fence so the tree has room to grow.

Drainage Devices Probably the most effective device to control water levels in a beaver pond sit-
uation is the Clemson beaver pond leveler. Developed at Clemson University, it has proven effective in allowing continual water flow and facilitating the manipulation of water levels in beaver ponds for moist-soil management that is beneficial for migratory waterfowl and shorebirds.
Elbow and stand pipe are optional. Needed only to manage water level if
maintaining pond is an objective.

-------20'-------

Beaver Dam

8" diameter 40 PVC pipe

Intake Device

1" re-bar 6' long

T-joint tilted with a drain plug may replace elbow.
Clemson Beaver Pond Leveler 6

Pond side

The Clemson beaver

Clemson Beaver Pond Leveler

pond leveler consists of

a 10-inch diameter per-

forated PVC pipe

encased in heavy-

gauged galvanized hog

wire. The encased por-

tion is placed upstream

of the dam or blocked

culvert in the deepest

part of the stream. It is connected to non-perforated sections of PVC pipe that are

run through the dam or culvert to a water control structure downstream. To

manipulate the water level of the pond, attach an elbow to the downstream end

with a pipe extending up to the desired water level. The Clemson beaver pond

leveler works best in relatively flat locations. It is effective because beavers can-

not detect the sound of falling or flowing water as the pond or culvert drains.

Therefore, they do not try to plug the pipe.

A "3-log drain" may be one of the most cost-efficient methods to permit water

flow through a beaver dam. To construct this drain, fasten together three logs

approximately 6-9 inches in diameter and 12-16 feet long. Logs should be wired

together with 2 logs side-by-side and 1 on top forming a triangle. A piece of light

gauge sheet metal (or old roofing tin) should be wrapped around the logs to act as

a pipe to permit water to flow between the logs. Place the three logs in the dam

with the upstream end of the logs at least one foot lower than the downstream end.

It is recommended to punch several holes in the top piece to improve water flow.

Beavers may build over the ends of the 3-log drain resulting in frequent mainte-

nance, so longer logs are suggested.

Variations on the 3-log drain include substituting PVC sewer pipe for the three

logs. Use perforated PVC (upstream end) connected to solid PVC (downstream

end). No sheet metal should be needed with this modification. Cap the upstream

ends or cover them with wire to keep debris from clogging the pipes.

In many instances especially in roadways, culverts are placed large enough to

handle the hydrologic needs of that area. However, recent evidence suggests

installations of oversized culverts in areas where beavers are present will mini-

mize the tendency of beavers to block culverts. Culverts should be enlarged to at

least a size that maintains the natural stream width. Oversized culverts may not

be a practical solution for established roadways but should definitely be consid-

ered when constructing new roads where beaver exist.

An important point to consider before installing any type of drainage device is

how beavers will react to the device. Oftentimes if beavers cannot plug a drainage

device or a leaking dam, they will simply build a dam in another location.

7

Repellents Using repellents to alleviate beaver damage is practical only on a small scale,
is extremely short-term and its effectiveness is uncertain. Individual trees or small areas of high value crops can be treated with repellents to keep beavers from chewing. However, there are very few -if any- repellents that are practical, effective, environmentally safe and registered for beavers. Commercial deer repellents like Hinder and Ropel may be used but their effectiveness on beavers is questionable.
Dam and Lodge Removal Beavers are highly industrious. Therefore, removing dams and lodges has lit-
tle impact on deterring beavers from an area. Dam removal is a laborious and expensive task. Often dams will be repaired by the next day. Continuous destruction of a dam will sometimes, depending on availability of construction materials, cause beavers to move to another site. However, displaced beavers may be even more troublesome at their new location. Therefore, dam removal is not effective unless the nuisance beavers are removed.
LETHAL CONTROL METHODS
As mentioned previously, there is no closed season on beavers in Georgia. Therefore, you may trap or shoot beavers year-round, day or night. To eliminate beaver problems, the most effective and efficient method is to kill beavers either by shooting or trapping.
Shooting Shooting beavers can be an effective and cost-efficient control method.
However, this option may not be available to those within city limits. Beavers are primarily nocturnal, meaning they are mostly active at night. Therefore, the best time to shoot beavers is at dusk. To shoot beavers at night will require some preparation. Locate the lodge or den and any active feeding stations. Additionally, tear out a portion of the dam prior to shooting. Position yourself near the lodge, feeding station or dam and simply wait for the beavers to appear at dusk. As darkness falls, a 6-volt light will aid in seeing the beavers and likely will not spook them. If you wait until a full moon night you many not even need a light! Beavers do not see well above water, so it usually isn't necessary to hide as long as the shooter stays motionless. If possible, shoot from an elevated position for safety and efficiency. At short range, a shotgun loaded with heavy steel shot (#2 shot or larger) or a .22-caliber rifle is recommended. Remember, there is a danger of ricochet when shooting around water so take proper precautions and know your surroundings. It is advisable to contact the local WRD Conservation Ranger before shooting at night.
8

Trapping In the majority of situations, trapping is the most effective, practical and envi-
ronmentally safe method of beaver control. Success depends on the trapper's knowledge of beaver habits, use of proper traps for the situation and trap placement. For this reason, Wildlife Resources Division (WRD), Game Management Section offices maintain a list of licensed nuisance trappers. In most cases, licensed trappers are experienced in trapping beavers and will be happy to assist you with beavers and other nuisance problems. Typically, a fee for their service is required. However, if you choose to trap on your own, a variety of sizes and types of traps may be obtained from your local hardware store or you can contact a WRD Game Management Section office for information on purchasing traps and trapping suggestions.
Besides eliminating beavers, trapping is extremely beneficial when managing beavers for a desirable population level. The trapping methods discussed below are designed to be lethal. It is possible to catch beavers in a live or cage trap, but is extremely difficult. If beavers are trapped alive, it is not recommended or legal to relocate beavers without the landowners permission. Few people are willing to have beavers released on their property plus diseases and parasites associated with the animal may be spread.
If you decide to trap in Georgia, remember:
Traps must be tended at least once each 24-hour period. Traps and snares must be labeled with the owner's name or owner's
permanent trapper's identification number provided by the department. Foot-hold traps for beavers must be smooth or rubber jaw steel. Body gripping traps in excess of 9- inches square must be used in water
or within 10 feet of water. Snares must be used in water or on land within 10 feet of water.
For a description of all the trapping regulations in Georgia, contact your local WRD Game Management Section office. Trapping regulations also can be found on the WRD Web site at www.gohuntgeorgia.com.
Example of a snare
9

Example of a 330 Conibear beaver trap
Dive Stick
For beavers, the most popular and effective trap is the 330 Conibear, a bodygripping trap. Designed for water use, this lethal trap is not likely to capture nontarget animals such as dogs and cats. It is effective in deep and shallow water. Lodge or den entrances, narrow channels, dams, natural inlets or trails worn by beavers are excellent places to set this trap. When setting this trap, place sticks in the ground surrounding the trap to restrict movement and funnel beavers into the trap. A dive stick should be placed on the surface of the water to trigger beavers to dive deeper and swim through the trap. To increase success, use bait (such as willow or cottonwood sticks) and lures (such as castor gland) to attract beavers. "Setting tongs" may be required to set the trap. Because this trap exerts tremendous pressure and impact when tripped, appropriate care must be exercised when using it to keep from injuring hands or arms.
Snares can be easily and effectively set in the water or on beaver trails at or near the water's edge. Advantages associated with snares are that they can be used to catch beavers alive for later dispatchment and otters are less likely to be caught in them. Snares should be made from a 4-5 foot length of 3/32" cable and a small piece of angle iron, which allows the snare to tighten but not loosen. Construct an 8-10 inch loop for the snare with the bottom either on the ground or 1-inch above the ground. Use a 14-gauge support wire long enough to run from a stake to the snare itself to keep beavers from leaving with the snare. A properly anchored snare is essential because beavers are powerful animals and can easily chew or pull out of an improperly anchored snare. Once caught, snares can be set with a drowning line to euthanize caught beavers. Snares can easily be made at home or purchased commercially. However, for the beginner, snares probably should be bought from a trapping supply company.
10

Experienced trappers have used foot-hold traps for many years. However, for the novice, foot-hold traps are not the best choice. If you choose to use a foothold trap, a minimum jaw spread of 6-inches is best. Traps are positioned in similar locations to that of body-gripping traps and snares. Beavers are powerful animals and to prevent them from escaping, drowning sets must be employed. The most common drowning technique is to use a "slide-wire" with one end fastened underneath the water. With the trap chain attached to the wire through a piece of angle iron, the trap will slide freely down the wire, holding beavers underwater. Traps set in this fashion are most effective when set where beavers enter or leave the water.
Finally, if you choose to use trapping as a beaver management technique, it is best to contact the local WRD Game Management Section office for guidance on purchasing and setting traps and trapping suggestions.

SUMMARY

The landowner should decide whether the beneficial aspects (waterfowl habi-

tat, hunting and fishing opportunity, non-game animal habitat, flood prevention,

irrigation potential) of having beaver on their property outweighs the possible

harmful aspects (flooding timber, pasture, or croplands, damage to roads, destruc-

tion of ornamental trees or shrubs) prior to using control measures. If action is

needed, take the time to carefully choose an appropriate and legal control meas-

ure for the situation.

For information on locations to purchase nuisance abatement equipment or

trapping supplies, a list of nuisance trappers in your area, or if you have addition-

al questions and are

unable to resolve nui-

sance beaver issues,

contact the local WRD

office (numbers listed at

the beginning of this

booklet). In addition,

the United States

Department

of

Agriculture, Wildlife

Services (706-546-

5637) can be contacted

to provide professional,

on-site assistance with

beavers or other nuisance Landowners should decide whether the beneficial aspects

wildlife problems.

of beaver dams on their property outweighs the negative

aspects prior to using control measures.

11

Example of typical beaver cuttings in Georgia
DNR Publication State of Georgia Developed November 2002; Revised June 2008
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