A few of weeks ago I had the opportunity to join a necropsy of a dolphin and a “whale” (albeit it a small one) at the Vertebrate OsteoPrep Lab at the Museum Support Center. The animals were found stranded along the beaches of Maryland and Virginia in the last couple of months in different stranding events and were collected by the Maryland Department of Natural Resources (MD DNR) and the Virginia Aquarium and Marine Science Center. The carcasses were kept frozen until the team could be assembled for the necropsies to determine the cause of death, to collect basic life history data and, of course, to collect their parasites!
This was really making the best of a sad situation. In addition to the necropsy and what we’d discover, these animals will be added to the scientific collection of the NMNH so they will be available for years to come for researchers and students to study. These necropsies brought together scientists with different specialties including research zoologists and post-doctoral fellows from the NMNH and other institutions, MD DNR biologists, wildlife veterinarians, a veterinary pathologist, NMNH photographers to document the whole experience, and myself as the parasitologist.
The first animal was a specimen of Feresa attenuata, Gray, 1874 or also called a Pygmy Killer Whale. Little is known about this species because they are so rarely encountered by humans, so this was a special opportunity to learn more about this species. The second animal was a specimen of Tursiops truncatus (Montagu, 1821) or a Bottlenose Dolphin. Interestingly, both the “whale” and dolphin belong to the family Delphinidae Gray, 1821 that contains dolphins, killer whales and pilot whales yet all are considered dolphins in spite of their common names!
During the necropsies, my role as the parasitologist was to collect any parasites that were revealed and preserve them for further scientific study. I was able to collect a number of worms including flukes (trematodes), tapeworms (cestodes), roundworms (nematodes), and thorny-headed worms (acanthocephalans).
Now, I have the fun of identifying all of these worms! Knowing the identity of these worms is important not only to gain a better understanding of the host associations and coevolution of these worms and their hosts, but also for understanding the interactions between the parasites and their hosts. For instance, the majority of these parasites didn’t appear to be causing much harm to the dolphins, but rather seemed to be “flying under the radar” of the dolphins’ immune systems.
I had a fantastic time working on such interesting animals (the parasites and their hosts!) with such a talented and interesting group of scientists.