HI! I work on the Ohlone tiger beetle. Two of which are gracing the top of this blog (photo credit to Leighton Reid). Yes, a beetle. It isn’t just any beetle (but what beetle is?) It is a gorgeous, brilliant green beetle that stalks its prey like a lion and exudes pre-digestive juices to kill it. Yep. It’s a predator, which makes it really important in the insect world, and beyond. It is also very endangered. It only occurs in Santa Cruz County, California, about 80 miles south of San Francisco. Its habitat is coastal grasslands- beautiful meadows that overlook the Pacific Ocean. Why is it endangered? Well, the Ohlone tiger beetle, which I lovingly call the OTB, needs bare ground. Open areas of dirt with no plants covering it. It needs this because it is a visual predator, using its large eyes to find and stalk its prey. It also needs bare ground to lay its eggs. Why? Because its babies are also predators that make burrows, or holes in the ground, from which the wait and jump out at prey as they walk past, only to eat them up at the bottom of the burrow. What is their prey? They eat anything they can catch- seriously I once saw a baby (or larva) eating a bumblebee! Nuts, right? It caught it while the bee was visiting flowers near the ground. CrAzY. Anyways, I’ll write more about the Ohlone tiger beetle and what I’m doing in the future, but I just wanted to introduce it here.
Why is it endangered? For a few reasons, but the number one reason is that, like I said, it lives in gorgeous prairies overlooking the Pacific Ocean- sound like a good place to live? Yeah, thousands of other people thought so too. Because of that, most of its former habitat, at least what we think its former habitat is, has been converting to housing. Besides that however, remember I said it needs bare ground? Well, the prairies the beetle calls home use to be grazed by larger animals, such as Elk (Anderson 2007, Wigand et al. 2007). The Elk have been hunting out of the area, unfortunately, and so the grasses no longer are grazed in many areas and this REDUCES bare ground. Luckily, we have cows and horses now, which we use in Ohlone tiger beetle habitat to keep up the bare ground. Another reason is that there use to be more bare ground just naturally. The meadows use to be covered in bunch grasses, which like the name sounds, bunch together to make more bare ground between them (D’Antonio et al. 2007). Now, most of the grasses in the prairies are European annual grasses that grow single blades in thick stands, REDUCING the bare ground.
What we’ve been doing to help the OTB’s habitat is create “disturbance” that creates bare ground. I’ve got a paper coming out about using scrapes to make bare ground (which I’ll profile when it is published), but we also commonly use cow and horse grazing as well as recreation to create and keep up bare ground. Recreation? What is this? Yes- hiking and biking help and endangered species! More to come in next post!