How do you find a rare animal that lives in swift-flowing streams, hides under enormous rocks, and swims faster than Michael Phelps? The critter we’re looking for is the hellbender (aka snot otter, grampus, devil dog, the list goes on…). The traditional way find these prehistoric-looking salamanders involves several steps: 1) recruit assistants with fast reflexes, 2) wait while everyone squeezes into wetsuits, 3) work your butts off lifting rocks, 4) blindly feel around for something squishy, and 5) hope you get lucky. But now there’s an easier way to do this, and it’s inspired by forensic science. Read more
Archive for Pennsylvania
With the help of the National Zoo’s pathologist, Dr. Tim Walsh, we solved the mystery of the yellow bump-covered darters! Official diagnosis? Grubs. That’s right, the good ol’ encysting fluke worm also known as the yellow grub (Clinostomum). This is a common parasite that starts its life in a snail, ends up in a bird, and in the middle lives in freshwater fish like darters, dace, shiners, and chubs. The worms hatch in the water, but have only hours to find a snail host or else face certain death. Once the larval grubs leave the snail, they enter the fish and set up shop in its flesh, making a swollen lump called a metacercaria. Are they harmful to fish? Sometimes. Severe infestations can be fatal. But then again many fish can get by just fine with a more modest number of the yellow, wriggling parasites. Are they harmful to humans? Well… It seems like the jury is still out on that one. Traditional thinking seems to be that, like other parasites of birds, this grub won’t infect people. But in 1995 a Korean man went to the doctor with pain and a “foreign body sensation” in his throat. Yup, you guessed it – he got grubs. Since then many other infections in humans have been reported, always involving individuals who eat uncooked fish. So it’s always a good idea to cook fish thoroughly.
For the time being we’ll keep an eye on this grub-infested fish population. It will be interesting to see how they cope with the parasites. Why did these grubs suddenly appear in a new fish population? We may never know, but we’re still looking for clues.
You can find out more information about yellow grubs and other fish parasites at the PA Fish & Boat Commission website.
In our last post we shared a video about hellbenders as “water detectors”. Other species (especially mussels and macroinvertebrates) can also help us detect problems in freshwater habitats. So when our science team is surveying for hellbenders in the wild, we make note of anything unusual we find. Last summer, we were wrangling hellbenders with Eric Chapman in western Pennsylvania, when he caught a fantail darter in his net. Darters are pretty common little fish (though some species are endangered) but there was something very unusual about this one – its belly was covered with yellow bumps! Eric had been surveying these streams since 2005 and had never seen anything like it. Read more
We met up with Eric’s team early this morning excited to wrangle some hellbenders. Barbara and Brian had never seen one in the wild, and we were going to a great site. Eric expected to find 15-20 benders today! But after the first hour of intense searching with no success, I was starting to wonder. It would pretty much have to start raining hellbenders for us to meet Eric’s goal…
Time for another trip to Pennsylvania! This time I have two people from the zoo joining me: Barbara Watkins (an animal keeper at the Reptile Discovery Center) and Brian Gratwicke (amphibian biologist, photographer extraordinaire, and my supervisor). Eric was originally going to survey the same creek we were at last time, but when he heard that my boss was coming, he rearranged their schedule and took us to the best hellbender site in the region. Woo-hoo! Yup, Eric’s pretty much the best research collaborator you could ask for.
Lauren and I spent the night at a campground just around the corner from the site. On our way into town, we stopped at a small grocery store and ended up making friends with the profusely muscular and impossibly tanned cashier clerk (Lauren opened the conversation with “Are you from Jersey Shore?” which I think he appreciated). Two of his friends were hanging out, and one of them, a nursing student, was very interested in the health component of our hellbender study. She’d never heard of a hellbender, and when I pulled out our life-sized model she was completely floored. How could a 2 foot long salamander that belongs in a “Jurassic Park” prequel be living in the streams of central Pennsylvania?!? Read more
This time it’s just me and Lauren, and we’re heading up to central Pennsylvania. Tomorrow morning we’ll meet up with Eric Chapman from Western PA Conservancy, who is leading the state’s hellbender surveys. I’ve never met Eric, but have heard that he’s a lot of fun to work with, so I’m really looking forward to this trip. It’ll be a quick one – we’re surveying all day tomorrow and driving back in the evening. After talking with Eric yesterday, I’m really eager to get some samples from this population. The surrounding area has been heavily impacted by Marcellus shale drilling (a.k.a. hydraulic fracturing or “hydrofracking”), and Eric has been finding fewer and fewer hellbenders at this site. Assessing the health of the last remaining hellbenders in this creek will be interesting – and hopefully useful from a management standpoint. We’ve got all our gear packed up (including a back-up blood centrifuge!) and are ready to go.