
Watch this giant leech eat an earthworm
Special | 1m 38sVideo has Closed Captions
This leech has a scary appetite. But it might be essential to its ecosystem.
The largest terrestrial leech in the South, Haemopis septagon, has terrifying eating habits. Yet, its presence in pristine ecosystems indicates that it might be beneficial in a way yet to be discovered.
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SCI NC is a local public television program presented by PBS NC
PBS North Carolina and Sci NC appreciate the support of The NC Department of Natural and Cultural Resources.

Watch this giant leech eat an earthworm
Special | 1m 38sVideo has Closed Captions
The largest terrestrial leech in the South, Haemopis septagon, has terrifying eating habits. Yet, its presence in pristine ecosystems indicates that it might be beneficial in a way yet to be discovered.
Problems with Closed Captions? Closed Captioning Feedback
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Learn Moreabout PBS online sponsorship- This is the largest terrestrial leach in the Southeast and it's hungry.
It hasn't eaten in more than a week.
What does it eat?
Earthworms.
The leach senses the worm's vibrations and pounces.
It probes the length of the worm looking for an end.
It finds it.
It uses its powerful throat to suck the worm down.
Lady and the Tramp style, the leach won't need to eat for another week.
Okay, yes, that was terrifying.
But let me make the case for the leach here.
This specific species, the haemopis septagon can only be found in like pristine ecosystems, like old growth forests.
So they're an indicator of high environmental quality even though we're not sure exactly what they do in those ecosystems besides eat earthworms.
- A wise tinkerer saves all the pieces.
- That's Alvin Braswell, an emeritus curator at the Museum of Natural Sciences.
He loves these leeches.
- Until we understand all these pieces in our world, it's a little bit dangerous to discard pieces simply because you don't know them or you don't understand them.
- Leeches are kind of like mosquitoes in that we're like, ugh, when we think about them.
But the oldest leach fossils date back 200 million years.
So they've been on this planet longer than we have and more than likely they're doing something very useful in the ecosystem that we just don't understand yet.
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SCI NC is a local public television program presented by PBS NC
PBS North Carolina and Sci NC appreciate the support of The NC Department of Natural and Cultural Resources.