Blanding's turtles wander a bit, making their conservation more complicated.
LONG-LIVED BLANDING'S TURTLE THREATENED BY HABITAT LOSS
June 5, 2016
NATURE
Jim McCormac
The average American lifespan is 79 years. One of our
coolest reptiles can best that. A cautious Blanding’s turtle can live to the
age of 80, or older.
Blanding’s turtle is, insofar as turtles go, a gem. A lunker
can reach ten inches in length. The high domed shell suggests the shape of a
German WW II army helmet. This carapace is blue-back, and adorned with fine
yellow stippling.
This turtle’s most distinctive feature is its lemon-yellow
throat and chin. They are highly aquatic, agile swimmers capable of capturing
live fish.
A Blanding’s turtle might be thought of as a leaky box
turtle. Its lower shell – the plastron – is hinged and can be folded up to seal
off the head. But the plastron doesn’t form the drum tight seal of its smaller
relative.
Amorous turtles mate in April and May, and commence the
business of making little turtles. Gravid females often wander far from water
to dig nests in dry soil, in which eight eggs on average are deposited.
Temperature dictates which sex the egg will yield. Eggs warmed to 72-82 F
produce females; those that reach higher temperatures result in males.
Hatchlings will have to wait at least 14 years before they
become sexually mature and ready to add to the stock.
Pioneer physician William Blanding first stumbled into this
beautiful turtle while exploring the Fox River in Illinois in 1830. His pickled
specimen still resides in the collections of the Philadelphia Academy of
Natural Sciences.
It took eight years before the turtle was named. In 1838
herpetologist John Holbrook published its formal description, which included
this statement: “… first observed by Dr. William Blanding of Philadelphia, an
accurate naturalist, whose name I have given this species.”
William Blanding’s original find came from the western
reaches of the turtle’s range. The bulk of its distribution is along the Great
Lakes, but populations are relatively few and scattered. The turtle is listed
as endangered or threatened in most states and Canadian provinces in which it
occurs.
Blanding’s turtle could be a totem of clean waters and
healthy wetlands. Habitat degradation has greatly reduced or eliminated them in
many areas.
Research has shown that Blanding’s turtles have a penchant
for wanderlust. A turtle tagged in 2007 near Toledo turned up again in 2015 – a
whopping 17 miles from where it was marked! Their peregrinations make
conservation complicated. Protecting only the wetland in which the turtles seem
to frequent is not be enough. Much larger habitat mosaics are necessary for
their long-term survival.
Blanding’s turtle is listed as threatened by the Ohio
Division of Wildlife and confined to Lake Erie and nearby environs. Two good
places to see them are Sheldon Marsh State Nature Preserve in Erie County, and
Magee Marsh Wildlife Area in Lucas and Ottawa counties.Naturalist Jim McCormac writes a column for The Dispatch on the first, third and fifth Sundays of the month. He also writes about nature at www.jimmccormac.blogspot.com
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