Transcript 10. Trumpeter Swan and Hawaiian Goose

Saving the Trumpeter Swan
and Hawaiian Goose: Recovery
Programs
Stacy Lackey
Trumpeter Swan Biology
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Has a white body, black bill, and a long
neck that is held straight in flight
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Eat aquatic plants, insects, snails
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Usually mate for life
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Build a big and bulky nest of reeds,
rushes, roots and grasses lined with
down
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Female lays 5-6 eggs in May and
incubates for 32 days
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“Cygnets” stay in nest only until they
can thermoregulate their temperature
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They have very little food reserve and
must start feeding quickly
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Male and Female molt at different times
so one will always be able to stay with
the cygnets
Similar Species
• Trumpeter swan has a size of 2425’’ and is the largest swan in the
world, weighing up to 35 lbs
Tundra Swan
• Similar to the Trumpeter are the
Tundra and Mute swans
• The Tundra sometimes has a
yellow spot on its bill, but is
overall smaller at 19.5-22.5’’
Mute Swan
• Mute has an orange bill and
ranges in size from
21- 24’’
History of Trumpeter Swans
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Trumpeter Swans were once fairly
common throughout most of the
northern United States and Canada
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Trumpeters nested in Minnesota
and Wisconsin until the 1880s
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The Trumpeters' historic breeding
range reached from western
Nebraska to central Michigan. It
extended as far north and east as
James Bay in Canada
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Market hunting and the millinery
trade rapidly depleted nesting
populations during the 19th century
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In the 1930’s, there were only 69
Trumpeter Swans remaining in the
continental U.S.
Early Findings
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By 1900, it was widely believed that
the species had become extinct
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Fortunately, a small nonmigratory
population survived in the remote
mountain valleys of Montana, Idaho,
and Wyoming
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Two nests were found in
Yellowstone National Park in 1919;
and in 1932, 69 Trumpeters were
documented in the region
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We now know that a population of
several thousand Trumpeters also
survived in remote parts of Alaska
and Canada
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Passage of the Migratory Bird
Treaty Act of 1918 gave protection
to trumpeter swans and other birds
and helped curb illegal killing
USFWS Recovery
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In 1935, the U.S. government established Red Rock Lakes National
Wildlife Refuge in Montana's Centennial Valley to protect the remnant
Trumpeter population
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Managed by the USFWS, habitat conditions quickly improved when
refuge personnel restricted livestock grazing and hay cutting in the
marshes, protected the muskrat population, provided winter food,
controlled predators, and more recently prohibited the use of lead shot
and lead fishing sinkers because of the danger of lead poisoning
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With protection at Red Rock Lakes and in Yellowstone National Park,
the Tri-state subpopulation, as it is now known, increased to 640 birds
by the late 1950s
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In an attempt to expand their range and chances of survival, Trumpeters
have been transplanted to locations with suitable habitat
USFWS Recovery, cont.
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Between the mid-1960s and the mid-1980s, the Tri-state subpopulation
declined. Productivity plunged in the late 1970s, and by 1986 only 392
birds remained
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Concern over the decline led to an extensive study that demonstrated
a close relationship between swan survival and the availability of
winter foods at Red Rock Lakes
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In 1987 and 1988, marked increases in supplemental winter grain
coupled with favorable weather led to a dramatic increase in the
number of cygnets produced at areas in and adjacent to Red Rock
Lakes
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In 1989, there were 565 birds in the Tristate Subpopulation
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Many other recovery programs were initiated, especially those in the
midwestern states of Michigan, Minnesota and Wisconsin. Wisconsin
has been the most successful of the three
Wisconsin Recovery
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Prior to 1987, it had been 100 years
since a Trumpeter had reproduced
in Wisconsin
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Beginning in 1987, Wisconsin
biologists flew to Alaska for nine
consecutive years to collect
Trumpeter eggs, then were hatched
in incubators at the Milwaukee
County Zoo.
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After they hatched, the young
swans were either placed in a
captive rearing program or decoy
rearing program until they were
released to the wild.
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The original goal was to establish
20 breeding pairs by 2000, and in
2004, there were 80 pairs
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They continue to captive and broodrear cygnets and release them back
into the wild, in hopes of reestablishing their old numbers.
Threats to Restoration
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They are vulnerable to illegal shooting, since they look so similar to
other species that can be hunted
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Collisions with power lines
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Predators: Snapping turtles, great horned owls, racoons and minks
which steal the eggs and kill the young
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Lead poisoning
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Widespread destruction and degredation of wetlands
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They must compete for food in these small areas with other migratory
trumpeters and birds that live there all year. As a result, some birds may
be in poor condition by spring. They lack energy for migration, egg
laying and incubation
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Other problems include funding, human disturbance and recreational
development in nesting areas
Management
• For management purposes, Trumpeters are divided into
populations based on their range
• About 1,000 Trumpeters occur in western Canada and include
birds that migrate to the Tri-state area. Many of these-swans
nest in the Yukon and the Northwest Territories. Together with
summer resident Tri-state swans, these birds comprise the
Rocky Mountain Population
• There are nearly 12,000 Trumpeter Swans in Alaska. These
birds, combined with western Canadian flocks and restoration
flocks from western refuges, comprise the Pacific Coast
Population
• A third population, the Interior Population, is made up of flocks
east of the Rocky Mountains and numbers about 500 birds.
The Trumpeter Today
• Once considered for federal 'endangered' status, the Trumpeter
is not officially listed as threatened or endangered
• In the Midwest, however, it is actually more rare than the
threatened Bald Eagle
• It has no official state status in Midwestern states, except in
Wisconsin, where it is listed as an endangered species, and in
Michigan, where it is a threatened species
• Today, estimates show about 16,000 trumpeter swans reside in
North America
• They are an overall success story, and their outlook is bright
Why worry?
• It is one of the rarest waterfowl in North America,
and the largest
• Environmental stability
• Aesthetics
• To many people, the Trumpeters are the
“embodiment of grace, beauty, and unspoiled
wildness”
Hawaiian Goose Biology
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Also known as Nene or Lava Geese
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Are extremely friendly and
approachable
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Front and sides of neck appear to have
black and white stripes
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Unlike all other geese, the Nene has
semi-palmate feet
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One of the smaller geese, range from
21– 26 ’’
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Winter breeding season: From
November to March
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Nest 2-5 white eggs in a “kipuka”
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Nests are down-lined, concealed well
under bushes, and usually in the same
area
Biology, cont.
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Feeds on both native and
introduced plants and herbs and
their seeds, buds, flowers and
fruits
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Habitat includes scrublands,
grasslands, golf courses,
sparsely vegetated slopes,
lowland areas
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Only waterfowl adapted for life on
lava flows, and are mostly found
in the rugged lava fields
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Only found in Hawaii
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Does not need fresh water, but
will use it when available
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Variety of calls from soft and
conversational to loud and
honking to “moo-”ing when
distressed
The Struggle of the Nene
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An estimated 25,000 Hawaiian
geese used to inhabit the
Hawaiian islands in the time of
Captain James Cook
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Europeans arrived in 1778 and
their numbers began to
immediately decline
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Their approachability became
their downfall
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They were overharvested to
feed those out in California
exploring and to feed people on
whaling expeditions
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The mongoose was introduced
in 1883
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Geese made easy targets and
the mongoose preyed on eggs,
chicks, and adults
Nene Struggle, cont.
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Hunting was allowed during the winter breeding seasons of the
Hawaiian goose, when they are most vulnerable
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This continued until the 1940’s
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Only 20-30 birds remained in 1949
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In 1950, a few were taken into captivity and by 1957, many
conservation efforts were underway
Early Recovery Programs
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Conservationists began breeding birds in captivity
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Early programs for returning geese to wild proved very difficult,
and the Nene was listed as an endangered species in 1967 under
the Federal Endangered Species Act
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There were constant releases in the beginning, but when releases
were reduced in the 1970’s, the population declined sharply from
875 geese in 1977 to 400 in 1980
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This suggested that releasing captive-bred geese had kept the
population artificially high
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Other factors of the declines included: low productivity due to
poor available nutrition
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Hawaiian Geese are also extremely vulnerable to predation by
introduced species such as the mongoose, rats, dogs, cats, and
pigs
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Much more work was needed to identify and remedy the causes
for the Nene's decline.
Recent Recovery Programs
• Between 1980 and 1989, various research and conservation
initiatives were carried out in Hawaii.
• The initiatives eventually culminated in the Nene Recovery
Initiative, a five year research program implemented by the
Nene Recovery Action Group, with members from the Hawaiian
Department of Forestry and Wildlife, Hawaiian National Park
Service, US Fish & Wildlife Service, University of North Dakota,
Smithsonian Institute and Wildfowl and Wetland Trust.
• The Nene Recovery Initiative had the goal of re-introducing the
Nene and for it to become self-sustaining in the wild and had
five objectives
Nene Recovery Initiative Objectives
1. To continue investigating the causes of the Hawaiian Geese low
productivity and survival rates
2. To investigate the success and cost of various management practices in
current habitats which increase the productivity and survival rates of the
Hawaiian Goose and to identify additional habitats that provide more of
the Nene's requirements
3. To assess release techniques by collecting data from intensive
monitoring of released individuals and to further research birds in
captivity
3. To produce an agreed Management & Monitoring Plan for the Hawaiian
Goose within the first 5-year phase and to stipulate the means by which
the plan could continue to be evaluated and enhanced until it becomes
self-sustaining without further releases.
5. To make the findings available and communicate them to all of the public
The results?
• These objectives were implemented through three work
programs involving 13 studies in total:
Management Research (5 projects)
Aviculture and Release Research (5 projects)
Long-term Monitoring (3 studies)
• This work demonstrated that five from the eight subpopulations on Hawaii were not self-sustaining due to a
variety of causes, including:
Low gosling survival
Poor foraging conditions
Predation by introduced predators (rats, cats, dogs,
pigs, mongoose)
Road fatalities - about 10 Nenes are run over by cars in
Hawaii every year
The Hawaiian Goose Recovery Plan
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Every Endangered species has to
have a recovery plan
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Published in 1983
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It outlines the essential elements to
accomplish a goal of establishing
2,000 geese on Hawaii and 250 on
Maui
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These elements are to:
1. Minimize the mortality rate in
the wild
2. Continue release of captivebred birds
3. To protect and improve habitat
where the Nene can maintain
their populations naturally
The Nene today
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Under some of the first captive breeding
efforts for an endangered species, the
bird's extinction has been prevented.
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Using new information and techniques,
this work has succeeded in establishing
new populations
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Now, some 1,100 Nene inhabit Hawaii,
Maui, Molokai and Kauai.
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Currently, Hawaiian Geese are being
raised in captivity at the Maui Bird
Conservation Center at Olinda and the
Keauhou Bird Conservation Center on
the Big Island. Young birds are then
released into protected habitats by
the State
•
The Wildfowl Trust in England also
plays a major role, distributing Nene’s
to zoos, aviaries, and the wild
What should be done and why?
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Substantial captive
populations ensure the
future survival of the Nene,
but further effort is needed
to conserve wild
populations
Most importantly, birds
need to be able to survive
in Hawaii without the
continued release of
captive-bred birds
Future conservation
priorities for the Nene are
currently being drafted in
the USFWS revised Nene
Recovery Plan
Further financial and
community support
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The Nene is the
state bird of
Hawaii, and its
residents are very
fond of the goose
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Aesthetic values
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It’s unique
characteristics
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Environmental
stability
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It is the 8th most
endangered
waterfowl species
in the world
Sources
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http://www.caprep.com/0904067.htm
http://www.fws.gov/pacific/pacificislands/wesa/nene.html
http://www.aloha-hawaii.com/hawaii/nene/
http://www.wwt.org.uk/threatsp/pastwwt/nene.htm
http://www.humboldt.edu/~jmb7002/stud/05.html
http://www.edf.org/documents/3738_species_Nene.pdf#search='hawaiian%20goo
se%20recovery‘
http://fwie.fw.vt.edu/WWW/esis/lists/e101029.htm
http://raysweb.net/specialplaces/pages/swan.html
http://www.dnr.state.wi.us/ORG/LAND/er/factsheets/birds/SWAN.HTM
http://www.trumpeterswansociety.org/
http://www.fws.gov/species/species_accounts/bio_swan.html
http://www.reallygoodnews.net/trumpeterswansreboundinwisconsin.htm
http://www.dnr.wisconsin.gov/org/land/er/swan.htm
http://www.umich.edu/~esupdate/library/96.09/smith.html
http://www.wesave.org/swan/program2.htm
QUESTIONS?