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GLIN==> NY Sea Grant Video Poses the Question, 'The Cormorant: A Double-crestedDilemma?'

The Cormorant: A Double-crested Dilemma?

Sea Grant video examines management strategies
of the fish-eating bird in the Great Lakes

Oswego, NY, July 31, 2000-- A complex struggle exists within the ecosystems
of  the  Great  Lakes, their watersheds and inland lakes, one that balances
biological  vitality with economic viability. With fish stocks in the lakes
sustaining  multi-million  dollar  commercial and recreational fisheries, a
new  15-minute  video,  "Managing Cormorants in the Great Lakes," describes
the   impacts  and  management  of  the  double-crested  cormorant,  a  now
rebounding  fish-eating  bird  species. Produced and funded by New York Sea
Grant  and  the US Department of Interior's Fish and Wildlife Service, this
$10  video  is  now available through Sea Grant's SUNY Oswego office, (315)

By  the  1950s,  after  almost  a  half-century  of  the  waterfowl's rapid
population growth throughout the Great Lakes, a control program was enacted
in  Canada that included nest destruction and human disturbance. Nesting in
New  York's  Lake  Ontario  waters  since  1945, this population of slender
shaped  foragers  soon  crashed,  though, with the introduction of chemical
contaminants  such  as  DDT  in the 1960s. Considered a grim example of the
Great  Lakes  ecosystem's  declining  health  some  30  to  40  years  ago,
devastation of the region's cormorant population resulted in the banning of
certain  pesticides  and  enactment  of  protective measures such as 1972's
inclusion of the species under the 1918 Migratory Bird Treaty Act (MBTA).

Today,  due  to 1970s and 80s population protection programs and the bird's
guarded  status  by the MBTA, cormorant nesting is at historic highs in all
the  Great  Lakes, Canadian waters and inland lakes in Michigan, Wisconsin,
New  York  and  Vermont.  Concern  and  controversy  have  accompanied this
population  resurgence, though. These large numbers of cormorants thrive on
a  food source comprised primarily of alewife, yellow perch and three-spine
sticklebacks.  Despite  ongoing  concerns  regarding their fish consumption
levels,  "increases  in  the  cormorant  population reflect the ecosystem's
continually  renewed  state  of  health,"  says video technical advisor and
NYSG's Fisheries Specialist Dave MacNeill.

While  consumption of fish varies among the bird species, the average adult
cormorant  is  estimated  to  eat  approximately  one  pound  of  three- to
five-inch  fish per day. "Although during nesting season cormorants consume
millions of these small fish, these are estimated to be a small fraction of
the  total  number  available," says Dave White, NYSG's Great Lakes Program
Coordinator and the video's producer and co-writer. Problems seem to exist,
however,  in  near  shore  waters,  where  cormorants  are known to feed on
stocked  fingerling  trout,  salmon  and  steelhead  before the fish have a
chance  to  disperse  into  the  lake.  Diet studies discussed in the video
indicate  no  system-wide  population level effects from predation of these
species  as  they  range  on  the  open range waters, but the effects large
colonies  of  cormorants  may  have  on their local populations is of great

Another  problem  the  region  faces  is competition between cormorants and
other  colonial  nesting  water  and wading birds -- gulls, ospreys, terns,
herons,  mergansers  and bald eagles -- for the same nesting sites in areas
such  as  Little Galloo Island in Lake Ontario and Ottawa Island's National
Wildlife  Refuge  in  Lake  Erie.  "A  special  concern  exists  when  this
competition  might  jeopardize the reproductive success of rare, threatened
or  endangered plant or animal species or when nesting threatens the rights
of private property owners," says White.

Population  resurgence in New York's Great Lakes basin has been accompanied
by  requests  for  action  by  the US Fish and Wildlife Service (USFWS), US
Department of Agriculture's (USDA) Wildlife Services and the New York State
Department of Environmental Conservation (NYSDEC). On the federal level, it
is  the  responsibility  of the USDA's Wildlife Services program to conduct
on-the-ground  management  activities  when  cormorants  cause  damage. The
NYSDEC,  responding  to  continual  concerns  from  its citizens task force
committees  regarding  the  impacts  of  cormorants  on fish and other bird
species,  has  utilized offshore fish stocking methods. Depredation permits
have  also  been  acquired  by  the DEC for cormorant control from USFWS to
prevent  nesting  colonies from becoming established on new islands on Lake
Ontario and from preventing the colony on Oneida Lake from jeopardizing the
nesting habits of common terns, a state-listed threatened species.

In  response  to public and private concerns, the USFWS is also cooperating
with  state  and federal fish and wildlife management agencies to develop a
comprehensive  national management plan for cormorants. Says Diane Pence, a
USFWS  wildlife  biologist,  "This  management  plan will help provide some
parameters  under  which  the  different  states can then define what their
situations  are and implement whatever management strategies they think are
necessary."   In   the   video,  USDA's  Richard  Chipman  details  several
strategies,  including  a mix of visual and auditory pyrotechnic repellants
as  well  as straight boat chases to reduce stopover time of cormorants and
thereby protect preyed-upon sport fish populations.

USDA  officials  have  found  success  with egg oiling practices but only a
temporary  fix  with  the  complete  removal  of nests and eggs. "While egg
removal  will  stimulate  additional egg laying and nest destruction leaves
cormorants  to  simply re-nest time and time again, oiling eggs keeps birds
onsite  to  continue  incubating  non-viable  eggs,  thus limiting breeding
pairs," says MacNeill.

"Achieving  management  of  cormorant  populations  is  a  long and complex
process   requiring   cooperation  from  all  agencies,  organizations  and
interested  parties with a stake in the resources of the Great Lakes," says
White.  "It will be to everyone's benefit to cooperatively work together to
manage the region's complex ecosystems."


For more information on this NYSG initiative,
contact David White at SUNY Oswego, (315) 341-3042.

The New York Sea Grant Institute is a cooperative program of the State
University of New York and Cornell University with administrative offices
at SUNY Stony Brook: 121 Discovery Hall/ SUNY Stony Brook/ Stony Brook, NY
Main Office Phone: (631) 632-6905 Fax: (631) 632-6917
Communications Office Phone: (631) 632-9124
E-mail: NYSeaGrant@notes.cc.sunysb.edu
Internet: www.seagrant.sunysb.edu

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