Vermont scientist rules detained crayfish a Vermont native
BURLINGTON, Vt. (AP) — Toughie the crayfish crossed the road in late June, unaware that she would be the subject of two weeks’ confinement in a newsroom.
At issue: the crustacean’s credentials to reside in Vermont. Was she an exotic invasive species — an unwelcome flatlander — or did she belong here?
The morning of June 29th began badly. Strolling just a stone’s throw from a tributary of the LaPlatte River in Shelburne at 6 a.m., the 3-inch long crayfish (or crawdad, or crawdaddy) only narrowly escaped the jaws of Patsy, a boxer-hound mix.
Free Press reporter Nicole Higgens DeSmet effected the rescue.
Then, noticing the suspicious orange tips on Toughie’s pincers (or claws, or chelae), DeSmet detained the creature for further questioning.
To the untrained eye, Toughie looked like a non-native rusty crayfish, a species made infamous in these parts for bullying native crayfish, gorging on fish eggs and otherwise making life difficult for denizens of the established food chain.
Days passed. The experts, afield or on holiday, were slow to weigh in. Desmet moved on to more pressing stories.
Toughie toughed it out, sequestered in a glass vessel, restricted to a diet of fresh water and the occasional inquiring stare.
Independence Day came and went.
Toughie posed for photographers, but with reluctance. She snapped her powerful tail and menaced her handlers with those distinctive, orange-tipped claws.
Her temper worsened as amateurs in her midst built damning evidence:
— Rusty crayfish — Faxionius rusticus (until 2017 known as Orconectes rusticus) — more properly belong in the Ohio River basin, where their native populations are held in check by better-matched predators, according to the U.S. Geological Survey.
— “There are currently no successful management techniques for rusty crayfish once a population is established,” warns the Lake Champlain Basin Program.
— Researchers at the Minnesota Sea Grant, responding to an upsurge in unwanted out-of-state crawdads, recommends their carcasses to fish-bait outfits.
— “You can humanely kill it by freezing it,” the Field Guide to Crayfish of the White River Watershed, adds helpfully. “You can also cook and eat it!”
One cold-hearted Free Press reporter suggested throwing the jar-bound arthropod to the gulls.
Instead, upon returning from the Fourth of July holiday, he circulated another round of photographs. This time, our trusty researchers chimed in.
A hands-on examination was in order, wrote Declan McCabe, chairman of the St. Michael’s College Biology Department and part of EPSCoR, a region-wide team of stream specialists. Until that time, it would be wise to keep Toughie under lock and key, he added.
“Honestly, in cases where it’s a tossup, I’d rather make the mistake of calling it invasive,” McCabe said.
Leslie Matthews, a watershed management scientist with the Vermont Department of Environmental Conservation, concurred with McCabe on the photo ID: Toughie was likely a “virile,” and thus a native Vermonter.
“However, in order to prevent the spread of invasive species or fish diseases, you should NEVER, EVER release a crayfish or any other aquatic organism into any waterbody. The risk of unintended consequences is too great,” Matthews wrote in an email. “I’m afraid that your crayfish must remain a pet, or must, as you put it, be fed to the gulls.”
Toughie had orange-tipped claws, but lacked a rusty’s signature black band beneath the orange tips (as well as a rusty patches along her sides), observed Jennifer Guarino a Randolph-based watershed consultant.
Guarino said her “crazy love of crayfish” predates the 2012 field guide to species that she co-wrote for the White River watershed.
And new thrills abound, she added in an email: There are indications that rusties have been breeding with the locals and spawning hybrids. If Toughie showed telltale signs of blush, she could be the product of a heated crayfish mashup.
Professor McCabe, drawn by the discussion, arrived in the newsroom on July 11 for a face-to-face interview with the 10-legged creature.
Within seconds, McCabe freed Toughie of the rusty stigma. As quickly, he grasped Toughie behind the claws, flipped her over and confirmed her gender.
Later that evening, Toughie was returned to her beloved LaPlatte River mud.
But the crayfish’s overseas kinfolk, it turns out, have thoroughly soiled her reputation.
Faxionius virilis has become a pest in England and Holland, according to the U.K.-based Centre for Agriculture and Biosciences International.
Virile crayfish, it notes, “are highly mobile, fecund and tolerant of a wide range of environmental variables making the species very successful invaders.”
Information from: The Burlington Free Press, http://www.burlingtonfreepress.com