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Meaning of frogs and salamanders: Wild-ID and beyond

Ashley Hosmer and Allison Sacerdote-Velat collect and document data on frogs and salamanders in an ongoing project at a Lake County site.
Credit: Dale Bowman

Ashley Hosmer photographed frogs so intently in close-ups that I finally asked about it.

Ask and learn.

Allison Sacerdote-Velat, the curator of herpetology at the Peggy Notebaert Nature Museum, said they are using a photographic mark-recapture program, Wild-ID, developed by Dartmouth’s Douglas Bolger. Think facial recognition
for animals.

‘‘It’s a non-invasive way to monitor living things,’’ she said.

With Wild-ID, animals don’t need to be tagged. They are cataloged by photograph, then released. Photos of recaptures can be matched by individual markings to earlier photos.

Allison Sacerdote-Velat checks an amphibian trap during monitoring.
Credit: Dale Bowman

On April 14, I went with Sacerdote-Velat and Hosmer, an amphibian field technician, to six spots at a Lake County site to check trapped frogs and salamanders.

Sacerdote-Velat said the day before, a rare day in the 70s, leopard frogs, spring peepers, wood frogs and chorus frogs were calling at once, catching up from our brutal spring.

‘‘Normally, they would have them calling in March, but they have been hanging out and feeding, so everybody is a little bigger now,’’ said Sacerdote-Velat, who noted most frogs weighed more than usual.

There are many reasons to monitor frogs and salamanders, including to see how restoration there affected amphibians.

A wood frog in hand during monitoring.
Credit: Dale Bowman

Early returns are dramatic. Sacerdote-Velat said in 2004, when doing earlier research, it was 80 percent blue-spotted salamanders and 20 percent chorus frogs. Now there are nine species: blue-spotted salamanders, chorus frogs, American toads, bullfrogs, green frogs, spring peepers, tiger salamanders, wood frogs and leopard frogs.

In monitoring any critter, there are the usual procedures: capture, data collections (date, measurements, location, sexing, etc.) and release.

Sacerdote-Velat and Hosmer had a system. They used blue Nitrile Gloves to handle the amphibians. Hosmer did most of the handling, changing gloves after each.

Ashley Hosmer measuring a frog during monitoring.
Credit: Dale Bowman

She weighed, measured and intensely photographed each. Sacerdote-Velat recorded data, then came the difference: She pulled out swabs and specimen bottles. Hosmer swabbed each amphibian multiple times, then the swab went into a bottle to be tested later for stress hormones and, more important, for the presence of chytrid fungus, which is wiping out frogs worldwide.

One reason diversity matters in the wild is to limit the spread of diseases.

The first stop was an ephemeral (temporary) pool. The traps held one female chorus frog.

In the warmth on April 13, some of the frogs got down to the delayed business of laying eggs. They found tiger-salamander eggs on buttonbush.

Then it was three chorus frogs, a blue-spotted salamander, a female wood frog and 12 clumps of wood-frog eggs in a buttonbush swamp where they had heard wood frogs calling the day before.

A handful of some of the wood-frog masses found during monitoring.
Credit: Dale Bowman

Sacerdote-Velat worked on restoration of wood frogs in 2008-10 at this site. The first calls were heard in 2014, and the egg masses finally came.

‘‘They come out in one shot,’’ she said. ‘‘Lay eggs, and they’re done.’’

There was also a crayfish and a leopard frog, about which  Sacerdote-Velat said, ‘‘We heard them calling so loudly yesterday, it sounded like a car engine.’’

At a flatwoods wetland, there was a spring peeper, more crayfish and the first of several central mudminnows.

At a floodplain pond, there were blue-spotted salamanders and a green-frog tadpole. A wood frog was heard calling, cold or not. Then it was another wood frog and another blue-spotted salamander.

One of several central mudminnows.
Credit: Dale Bowman

It was time. Cold and dampness thickened. Sacerdote-Velat, worrying like a mother, hoped that not too much ice would form and that there would be enough water in the coming weeks.

A green-frog tadpole found during monitoring.
Credit: Dale Bowman