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Have you ever seen a siren? I don’t mean one of
temptresses of Greek myth, or the thing that makes noise atop an emergency
vehicle. I mean the amphibian called a siren. It’s an eel-like creature that’s
actually a salamander. As adults, sirens get more than two feet long. They’re
somewhat variable in color, but mostly dark, and they have two undersized front
legs (but no rear legs) and external gills.
Like most residents of east central Illinois, I’ve
never seen a siren. But Jessica Runner of Danville has, and not a mile from her
home. Here’s how.
Runner is a busy mother of two young boys who
manages the shoe department at Carson’s and owns a landscaping business with
her husband. But she is also a dedicated birder who has cultivated a growing passion
for nature photography in recent years.
Often when Runner has time off work she drops by
Heron Park, which is at the north end of Lake Vermilion and just minutes from
her home by car. Its wetland complex makes an excellent spot for birding, and
it hosts a rookery where great blue herons nest.
One morning at the end of May this year as Runner
approached the park in her car she spotted a great blue heron stalking a meal
in a shallow pond that borders the road. She quickly pulled over, and, using
the car for a blind, photographed the bird over a period of 40 minutes as it
worked to procure breakfast.
Great blue herons are patient hunters. They avoid
spooking prey by moving extremely slowly until they’re close enough to stab it
with a quick extension of the neck.
Unfortunately for Runner, her own patience did not
quite match the heron’s, and her attention was focused on a family of wood
ducks at the moment it struck. To her delight, however, the heron ran back
toward her with its still-wriggling prize, and she was able to photograph the
bird’s battle to subdue it. [Photo of great blue heron with siren by Jessica Runner, used with permission.]
As she took pictures, Runner thought she was
seeing her bird kill and then eat a snake. But when she later saw the images on
a computer screen, she realized the snake-like creature had legs, so she
forwarded them to a friend in Urbana. He identified it as a siren.
Runner wasn’t the only person excited about her
discovery. She contacted Chris Phillips at the Illinois Natural History Survey
to tell him about her pictures, since the Survey’s Field Guide to Amphibians and Reptiles of Illinois shows no records for sirens in Vermilion County.
“It goes to show you,” Phillips said, “there are
still some surprises out there for a herpetologist in the Midwest.”
On one hand, he continued, it seems odd that
sirens would turn up in Vermilion County because they are more common in the
southern part of the state and along major rivers. Besides, he and other field
scientists have studied the reptiles and amphibians of Vermilion County for
decades and never been able to find sirens there before.
On the other hand, it’s also a potential boon to
have them located where they’re so accessible for study by UI faculty and
students. “It’s only a forty minute drive from campus,” he pointed out, “and
during high water we could throw a trap into that pond right from the truck.”
Sirens are weird creatures, and there is much to
be learned about them. They maintain throughout life characteristics that most
amphibians lose as adults: they continue to live in water, they keep their
external gills and they develop only tiny front legs.
They can survive prolonged dry periods by encasing
themselves in slime that forms an airtight sac and going dormant, but for how
long, nobody knows. Nor have scientists ever witnessed their courtship and
mating, so they can only speculate about that based on the siren’s physical
characteristics.
I suppose there are people for whom the discovery
of an unexpected amphibian nearby causes no excitement, but I’m not among them.
As the temperatures warm next summer, I look forward to helping catch sirens at
Heron Park. Don’t worry if you’re not there, I’ll take pictures.
