A team of researchers co-led by David Relman, MD, professor of medicine and of microbiology and immunology, has discovered previously unknown species of bacteria in dolphins trained by the U.S. Navy.
You’ve probably heard of security dogs that help sniff out drugs, bombs or land mines — the U.S. Navy uses dolphins, the dogs' marine equivalent, to protect ships and submarines by detecting sea mines and underwater intruders.
The researchers are cataloging the bacterial communities living inside the dolphins at the Navy’s Marine Mammal Program in San Diego. They analyzed samples from the dolphins’ mouths, stomachs, rectums and respiratory tracts. The results were recently reported in Nature Communications.
The research team found a startling diversity of bacteria, especially from the dolphins’ mouths. “About three quarters of the bacterial species we found in the dolphins’ mouths are completely new to us,” Relman said in an online piece.
The researchers also tested the Navy’s sea lions and the surrounding seawater. The newly discovered bacteria found in the dolphins were not seen in the sea lions, even though the dolphins and sea lions were fed the same fish and swam in the same water. The bacteria in the seawater were also very different from the bacteria in the marine mammals.
Relman began working with the Navy 15 years ago to help keep the dolphins healthy. However, the research may have a much wider impact, Relman explained in the story:
There’s a lot of concern about the changing conditions of the oceans and what the impact could be on the health of wild marine mammals. We would love to be able to develop a diagnostic test that would tell us when marine mammals are beginning to suffer from the ill effects of a change in their environment.
The research team plans to expand their study to include other marine mammals, including sea otters, harbor seals and elephant seals.
Jennifer Huber, PhD, is a science writer with extensive technical communications experience as an academic research scientist, freelance science journalist, and writing instructor.
Previously: Beyond the oil spill, the human-ocean health connection, Study shows toothed whales have persisted millions of years without two common antiviral proteins and Investigating the human microbiome: “We’re only just beginning and there is so much more to explore”
Photo by National Marine Mammal Foundation