- Nine pygmy rabbits died at Northwest Trek near Eatonville
during the past month as an unexplained disease swept through the endangered
population.
-
- Trek officials said the deaths constituted about half
of the stock, which was being bred and reared in captivity for eventual
release into the wild.
-
- The cause of the rabbits' deaths is unknown, but "the
situation is being handled as a highly contagious, acutely lethal disease,"
according to a news release.
-
- They were of normal weight and eating well before their
deaths, the release said.
-
- There "were no visible signs of distress or abnormal
behavior within hours" of their deaths.
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- Daily treatment The remaining rabbits were moved indoors
and isolated in a clinic, where they're getting daily medical treatment.
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- The sudden deaths canceled Trek's plans to release some
of the animals into Washington's Columbia Basin later this month.
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- Trek is one of several partners in the Pygmy Rabbit Recovery
Program led by the State Department of Fish and Wildlife, the news release
said.
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- The Oregon Zoo and Washington State University also participate.
Trek was scheduled to release at least 5 rabbits.
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- Animals from Oregon and WSU will be set free in Douglas
County as planned Tuesday [13 Mar 2007], the news release added.
-
- Wildlife officials announced this week they planned to
release 23 of the captively bred animals. They are to be placed in artificial
burrows until they can dig their own.
-
- The Columbia Basin Pygmy Rabbit is listed on the state
and federal endangered species lists. To ensure the survival of some pygmy
rabbits, animals from the Columbia Basin stock were crossbred with Idaho
pygmy rabbits, according to a news release from the wildlife service.
-
- The Trek rabbits, part of the breeding and rearing program,
were not on public display.
-
- http://www.theolympian.com/130/story/69116.html
-
-
- From Joseph P. Dudley, Ph.D fnjpd@uaf.edu Research Associate
Institute of Arctic Biology - University of Alaska Fairbanks Department
of Earth Science - University of Alaska Museum
-
- "Pygmy Rabbit (_Brachylagus idahoensis_) is listed
as an endangered species in the state of Washington, and on the Federal
Endangered Species List. Idaho lists it as a State Species of Concern.
This rabbit very small, and typically brown to slate gray. Its ears have
a white margin and it has a small tail. It has a very small and depressed
population size and is threatened by habitat loss and predation as well
as some introduced diseases. While a few rabbits remain in the wild, most
of the remaining population has been placed in 2 captive breeding programs.
Probably less than 50 rabbits of this subspecies remain.
-
- "The smallest rabbit species in North America, the
pygmy rabbit measures 9.2-11.6 inches (23.5-29.5 cm) in length, weighs
a slight 0.88-1.02 lbs (398-462 g), and is able to fit in the palm of a
hand. Unlike other rabbit species, the pygmy rabbit digs its own burrows
in deep, loose soil. They are dependent upon sagebrush for food, comprising
98 percent of their winter diet and a good portion of their spring and
summer diet. Mortality, chiefly from predation, is high for both juveniles
(an estimated 50 percent don't survive the 1st 5 weeks) and also the species
in general, which has a mortality rate of up to 88 percent per year. Predators
include weasels, coyote, badgers, bobcats, raptors, and humans, as many
hunters can't distinguish them from other rabbit species.
-
-
- It is suggested that areas of tall sagebrush, a specialized
habitat requirement, can be promoted by disturbances such as ungulate
grazing and perhaps even by the burrowing and feeding activities of the
rabbits themselves. Relatedly, more research needs to be conducted on how
cattle grazing affects key habitat for the pygmy rabbit. Though the historical
population and range of the pygmy rabbit is unclear, evidence suggests
it was significantly larger than at present.
-
- This decline is primarily due to habitat loss and fragmentation
through development, agricultural conversion, and sagebrush burning to
promote grasses for livestock forage. The current population total is similarly
unclear, as some states (such as Washington) have active surveying programs
while others have virtually none. In severe danger of extinction, the Washington
population has declined from an estimated 250 rabbits in 1995 to a current
estimate of zero. Several small populations known to exist 6 years ago
are now extirpated due to wildfire and disease.
-
- Recently, the Washington Department of Fish and Wildlife
(WDFW) has initiated a captive-breeding program with hopes of revitalizing
the population. There are 6 rabbits currently in captivity and they are
hoping to find a total of 20 for the program. Originally planning on crossbreeding
with Idaho pygmies, the idea was scrapped in favor of preserving the Washington
sub-species when it was found the 2 are genetically different. Strategies
to enhance pygmy rabbit habitat and population numbers outlined in the
Washington State 1995 recovery plan are many and include: monitoring, determining
population trends through burrow surveys, developing techniques for estimating
numbers, researching the effects of grazing, protecting the population
through fire management, keeping track of relative abundance of predators,
enhancing existing habitat, and creating new suitable habitat and habitat
corridors."
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- Indeed with so few of this species, the deaths at the
captive center are quite alarming.
-
- There is not enough information here to understand the
clinical signs of the illness or the deaths to completely understand what
is happening to the animals. We will hope for speedy recovery and for more
information from an authoritative source.
-
- A close up of a pygmy rabbit may be seen at: http://www.oregonzoo.org/Newsroom/2005%20releases/images/rabbit.jpg
and at: http://en.wikipedia.org/wiki/Image:BRACHYLAGUS_IDAHOENSIS.jpg
-
- Portions of this commentary have been extracted from:
http://www.pacificbio.org/ESIN/Mammals/PygmyRabbit/pygmyrabbit.html
-
- - Mod.TG]
-
-
- Patricia A. Doyle DVM, PhD
- Bus Admin, Tropical Agricultural Economics
- Univ of West Indies
-
- Please visit my "Emerging Diseases" message
board at:
- http://www.emergingdisease.org/phpbb/index.php
- Also my new website:
- http://drpdoyle.tripod.com/
- Zhan le Devlesa tai sastimasa
- Go with God and in Good Health
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