Written by Kristina
Smith, Watchdog/enterprise Reporter, 10/2/13
Fast facts on Lake Erie water snakes
• The snakes live only on
the Lake Erie islands and prefer rocky,
shoreline habitat.
• Females grow to an average of 3.5 feet in length. Males grow to 2.5 feet.
• Round gobies, an invasive fish, make up 98 percent of the snakes’ diet.
• Their average life span is 8 to 10 years, but they can live 15 or more.
• They were removed from the U.S. Endangered Species List in September 2011.
They are considered a federal threatened species and listed as an Ohio endangered species.
• They mate in late May and early June. Females give live birth to about 30
babies in September. Babies tend to be the size of a pencil.
For information on the snakes, visit www.respectthesnake.com.
PUT-IN-BAY — Two years
after the Lake Erie water snake was removed
from the federal Endangered Species List, its numbers are robust and holding
steady, a researcher said.
And the snake can thank
an invasive fish for a large role in its comeback.
The resilient snakes have
turned to the massive numbers of the round goby, brought to the Great Lakes
through ocean-going cargo ships’ ballast water, as their main source of food,
said Kristin Stanford, Ohio State University Stone Laboratory education and
outreach coordinator, research scientist and herpetologist.
And the result has been a
population boom of water snakes that grow faster, bigger and produce more
young, she said.
Lake
Erie water snake
populations have thrived since the mid-2000s and are holding steady at 10,000
to 12,000 snakes, she said.
“That’s probably where
they’ll stay,” said Stanford, who led a recovery plan to rebuild the snakes’
numbers. “We have been seeing kind of a leveling off of the population.”
The Lake Erie water snake
lives only on the Lake Erie islands and is
related to northern water snakes often seen along mainland shores. Lake Erie water snakes can be gray or have a banded brown
and gray skin.
Their numbers dwindled to
2,000 in 1999. Development took over rocky shoreline habitat they prefer, and
they were often killed by people who did not want them around.
The snakes are not
venomous. If startled, they can be aggressive.
Females are bigger than
males. They grow to an average of 3.5 feet in length, a foot longer than the
males’ average.
Lake
Erie water snakes’
average life span is eight to 10 years, but they can live 15 or more, said
Stanford, who also is known as “the Island Snake Lady.”
Before the gobies invaded
the Great Lakes in the 1990s, Lake Erie water
snakes ate other bottom-dwelling fish such as sculpin, catfish and darters.
“We just really don’t see
those food items in their diet anymore,” Stanford said.
Those fish are still
found in Lake Erie’s Western
Basin, but their numbers
are much smaller since the goby invasion. Gobies are the dominant
bottom-dwelling species in Lake Erie’s Western Basin,
said Jeff Reutter, director of OSU’s Ohio Sea Grant College Program.
Stanford, citing a 2006
population estimate, said there are about 9.9 billion gobies in the Western Basin. Lake Erie
water snakes eat about a million of those each year.
Predators of the adult Lake Erie water snakes are large birds, including herons,
egrets and bald eagles. Smaller snakes are eaten by smaller birds, raccoons and
other animals, Stanford said.
The Lake
Erie water snake recovery is considered a huge success for
endangered species. In 2011, the snakes were the 23rd species to be removed
from the federal list, Stanford said.
“It is pretty uncommon,”
she said. “That’s why we are very proud of the work we were able to accomplish
in such a short period of time to recover the (snake) and also why the U.S.
Fish and Wildlife Service uses it as an example of success.”
But that doesn’t mean
Stanford’s work is done. She and her fellow researchers are in the third year
of the five-year post-delisting monitoring plan for the snakes.
They continue to tag and
monitor the snakes to make sure the population is not threatened and that
returning the snakes to the Endangered Species List is not necessary. They also
continue to educate people about the snake and its role in the Lake Erie ecosystem.
“After the plan is
up, we will still likely continue to monitor the snakes because we have such a
huge data set — one of the largest for any snake in the world — and we would
like to keep that going,” Stanford said.
Posts
