STACEY VANEK SMITH, HOST:
Most of us have heard of saving the elephants or saving the polar bears, but what about saving their parasites? Scientists are increasingly finding that parasites are a key part of ecosystems, and many are at risk of extinction. NPR's Lauren Sommer explains.
VANEK SMITH: When your job is to study parasitic worms, not everyone wants to hear what you do for a living.
CHELSEA WOOD: It's not a popular topic of conversation at cocktail parties, I can tell you that.
LAUREN SOMMER, BYLINE: Chelsea Wood is an assistant professor at the University of Washington.
WOOD: Parasites have a major public relations problem. They're gross and slimy, and most people don't really like thinking about them. But the fact is that they're really important in ecosystems.
SOMMER: Wood says, just look at a flatworm worm she studies in California ponds. First, the parasite starts as an egg inside a bird.
WOOD: The birds poop out the egg, which infects snails.
SOMMER: Then, it goes from the snail to a frog. But the parasite needs to get back in a bird to finish its lifecycle. So it causes deformities in the frog's legs, which makes it easier for birds to catch and eat them, which helps sustain the bird population. Wood says it shows how humble parasites can influence the entire food web. But if birds are threatened...
WOOD: We're going to see some parasites decline possibly to extinction in the presence of environmental change.
SOMMER: Which is why a team of parasitologists released a new parasite conservation plan. The first step is simply identifying them. Of the millions of parasite species, only about 10% are known to science, says Skylar Hopkins of North Carolina State University.
SKYLAR HOPKINS: We know nothing about them. We don't need even know their name, and we definitely don't know what they're doing within ecosystems.
SOMMER: Many parasites are just as vulnerable as their host animals are to climate change and habitat loss. But even though an animal may be listed as endangered, its parasites aren't. But they could be added alongside their more visible hosts.
HOPKINS: It would be a really great way, a really easy way, potentially, to get a lot of mileage for parasite conservation.
SOMMER: Because humans tend to gravitate to animals like us.
JACOB MALCOM: It is the wolves and the grizzlies and the polar bears, mostly the mammals that really get people's attention.
SOMMER: Jacob Malcom works for the advocacy group Defenders of Wildlife. He says it's not all bad that humans focus on those charismatic critters. Saving their habitat can also help the less charismatic species in their ecosystem. So what are the chances his group launches a save the leeches campaign?
MALCOM: It's pretty close to zero.
SOMMER: So now is the time. Leech lovers of the world, unite.
Lauren Sommer, NPR News.
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