Refuge Notebook
Article
May
28, 2004
A warning about introducing exotic birds
By Todd Eskelin
The recent discovery of crawfish in a local stream stirred quite a reaction
from concerned citizens. It exposed how easily threats can occur to the fish
and wildlife that populate our watersheds. The crawfish story follows a disturbing
pattern along with the illegal introduction of yellow perch and northern pike
into local waters. The threat of such exotic fish to anadromous and resident
fish species is well known and often discussed among fishermen.
The crawfish
story also points out an often-overlooked problem that is very prevalent in Alaska
and specifically on the Kenai Peninsula. Much of the attention on invasive species
focuses on fish, plants, and insects, but invasive bird species are rarely seen
as a threat to wildlife in our area. Only Rock Doves (pigeons) and European Starlings
are listed as invasive species by various state and federal agencies.
Though
pigeons and starlings do pose significant threats, there are many other introduced
bird species on the Kenai that pose a risk to native birds, other wildlife, and
even humans. Since the Kenai National Wildlife Refuge initiated the rare bird
hotline in February, I have received numerous reports of birds that are not native
to our area and in some cases not even native to North America. I recently had
a pair of Chuckar land in my yard briefly and then fly off. There have also been
sightings of Turkey, California Quail, Ring-necked pheasant, Bobwhite, and various
ducks and geese.
I would like to believe that these birds have simply escaped
from their pens and their release was a total accident. Unfortunately, it is more
likely a case of well-meaning people buying and releasing the birds in an attempt
to have them breeding in the wild. What is baffling to me is that we jump at
the first sight of crawfish, yet we don't even bat an eye when an introduced bird
walks across our yard. We still allow groups to purposefully introduce game birds
into the local environment with little regard for possible problems that may arise
down the road.
The introduction of Starlings into North America started
with around 100 birds released in Central Park in New York City in 1890 and 1891.
Europeans had recently settled in the New World and wanted to establish all of
the birds mentioned by Shakespeare to bring a little flavor of home with them.
This is not too dissimilar from people originating in the Midwest bringing a few
yellow perch with them or Oregonians wanting a few Chuckar running around in their
backyard.
There are conservative estimates that the Starling population
has reached over 200 million birds since that initial release approximately 100
years ago. These birds out compete native birds for food and nest sites. Large
flocks can devastate food crops grown for livestock and do considerable damage
to fruit crops grown for human consumption. They are also vectors or hosts for
a multitude of diseases. At least 50 different human and livestock viruses and
diseases have been documented in the droppings of Rock Dove and Starlings in North
America.
The list of viral diseases is especially disturbing. Viral diseases
like yellow fever, dengue fever and many types of encephalitis have been isolated
from Starlings. Starlings are also one of the many bird species documented as
vectors for West Nile Virus. Starlings now range as far north as Fairbanks and
south through most of Mexico.
This is just an example of how well-meaning
folks release a few birds into the wild and the results can be devastating. There
was no way to predict the harmful effects Starlings would have on our continent
when those first birds were released.
So, is it worth the risk to plant
a few rabbits or quail in your back yard if they could potentially eliminate native
species from the enjoyment of our future descendents?
There are some simple
steps to stop non-native species from getting established. Don't be tempted
when the local pet store has a sale on Mallard chicks to buy and release them
into the wild. We also should make a concerted effort to remove these birds
from the wild when we see them. Give birds the same attention that we give to
crayfish or northern pike. We may not know the exact risks they pose, but why
wait until they are uncontrollable to react to the threat?
Todd Eskelin
is a Biological Technician at the Kenai National Wildlife Refuge. He specializes
in birds and has conducted research on songbirds in many areas of the state. Previous
Refuge Notebook articles can be viewed on the Refuge website at http://kenai.fws.gov/.
You can check on new bird arrivals or report your bird sighting on the Kenai National
Wildlife Refuge Birding Hotline (907) 262-2300.
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