Results
of Rattlesnake Hills Elk Management Strategies 2000-2005
Mike Livingston, District 4 Wildlife Biologist
The Rattlesnake
Hills Elk Herd (popularly known as Hanford elk) resides east
of the Yakima River and west of the Columbia River. It grew
from less than 10 colonizers in winter 1972-1973 to over 800
in 1999. Core range has been the Hanford Reach National Monument’s
Arid Lands Ecology Reserve (ALE) and private land to the south
and west in Benton and northeastern Yakima Counties.
Security
provided by Department of Energy’s land closure of Hanford
and abundant forage provided colonizing elk excellent living
conditions. Furthermore, mild winters permit elk to gain weight
in winter unlike those elk ranging in the Cascades that often
lose weight in winter. The most stressful time for Rattlesnake
Hills elk is late spring and summer when bunchgrasses and
cheatgrass dry out and become less palatable and nutritious.
This drying of grasses may explain why some elk have developed
a habit of migrating off ALE onto private farmland in spring
and summer.
Dryland
wheat farming is extensive on private land surrounding ALE.
Elk seek out the young green wheat in spring for forage. They
also occupy the several springs on private land surrounding
ALE. Elk damage wheat by creating extensive trails in early
spring and by trampling as it grows. WDFW is responsible for
reimbursing farmers for elk damage to their crops. Since 1999,
over $546,000 has been paid to farmers in the Rattlesnake
Hills area for wheat damage caused by elk.
Three
tools have been used in an attempt to reduce damage; hazing,
harvesting, and trap and relocate. Hazing has been conducted
from the ground and air using fixed-wing aircraft. Initially
hazing worked very effectively. Eventually though the elk
learned that they were not in danger and resumed their behavior
patterns. Hazing works best when used in conjunction with
other techniques.
Hunting
is an effective tool to control problem wildlife through both
deterrence and population reduction. Three factors have caused
this tool to be less effective in the Rattlesnake Hills. First,
the elk typically damage crops during the non-hunting season
(spring and summer). Fall hunting does not necessarily target
the elk causing damage. Second, the majority of the land is
private. Farmers are reluctant to permit access to hunters
because some past hunters have damaged property and demonstrated
unsafe hunting practices. Third, and most problematic for
population control, the ALE has functioned as a de facto elk
refuge. The elk seek refuge on ALE each year shortly after
the first hunting season opens.
Over
the years, WDFW has implemented various combinations of hunting
seasons in an attempt to increase harvest. Seasons have been
uncommonly long stretching from August through December. During
6 of the last 7 years, general seasons exceeded 40 days for
antlerless or either sex harvest. Despite liberal, long seasons,
harvest has only exceeded annual recruitment once. In June
2000, a wildfire virtually eliminated all forage on ALE, prompting
elk to seek food elsewhere which made them vulnerable to hunters.
That year over 200 elk were harvested. Also, in February 2000,
a large trap and relocate effort was conducted on ALE. A total
of 174 elk were removed from the population as a result. The
trap and relocate effort and high harvest reduced the herd
from approximately 800 to 500 head.
The use
of trap and relocate can be an effective, short-term tool
as proven in 2000. It is an expensive tool, however, that
can be dangerous for both elk and workers. Finding locations
to relocate elk to can be difficult. Relocated elk can become
problems in their new area. For these reasons, WDFW only uses
trap and relocate for limited short-term objectives, and usually
in conjunction with other tools.
Since
2000, harvest of elk has ranged between 53 and 79 each year.
A survey conducted in January 2005 yielded a population estimate
of 670 elk. This estimate is almost double WDFW’s objective
of 350 elk established for this herd in 2002. By fall 2005,
it is expected, given this herd’s average annual calf
recruitment rates, that the population will reach 750-800.
This
year WDFW added an additional method of increasing harvest.
Special permit seasons for advanced hunter education (AHE)
graduates were created within two new elk areas in GMU 372.
These special permit hunts are being coordinated by Hunt Masters.
Private landowners around ALE have been cooperating with WDFW
to coordinate hunts. Cooperation between landowners, WDFW,
the Hunt Masters, and AHE hunters is critical. Hunts must
be highly coordinated in this open country if hunters are
to be successful. If you received a special permit for any
hunt within the Rattlesnake Hills, Blackrock or Corral Canyon
you should wait until the Hunt Master contacts you before
venturing out to the area.
In addition,
cooperating landowners were provided with permits to distribute
to hunters of their choosing. That way they can select hunters
who know the property and can more effectively harvest elk.
The majority of the permits are for antlerless elk with a
few spike bull and any bull permits. The permits are valid
for August to February to ensure consistent pressure over
a long period of time to harvest and to keep elk hazed off
the private land.
Harvest
on surrounding land alone cannot be expected to keep up with
annual recruitment no matter how sophisticated hunting seasons
become. WDFW is working with the US Fish and Wildlife Service
to develop a future process for using the public and tribes
on the National Monument to reduce the elk herd. Together,
these integrated harvest strategies on ALE and surrounding
private lands should result in achieving population objectives
and reducing crop damage.
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