In honor of Five Valleys’ 10th anniversary of owning the Rock Creek Confluence, we engaged our partners the Missoula Butterfly House and Insectarium, Five Valleys Audubon, the Montana Native Plant Society and the Montana Natural History Center to undertake a “bioblitz” that documented the property’s flora and fauna. Combined with our Motus and University of Montana Bird Ecology Lab stations, we now have robust data on the many species the Confluence supports.
From a distance, this sparse patch of sunflowers looks nondescript. You’d have no idea that it’s the stage for a gripping insect drama. But here we are, five adults, completely engrossed in this miniature world in front of our eyes. We’ve already spotted a golden paper wasp, two magnificently hairy velvet ants, and a spined assassin bug. And we keep spotting more creatures, each of them exciting. It’s a scramble to keep track of them all and get photos.
Today’s outing is part of a season-long insect inventory at the Rock Creek Confluence property. Glenn Marangelo, of the Missoula Butterfly House and Insectarium, is leading the inventory. We’re focusing on the wetland area that Five Valleys Land Trust has been restoring for the last ten years. And from this patch of sunflowers along the dry edge of the wetland to the shallow water itself, we’re finding a thriving assortment of creatures.
The golden paper wasp (Polistes aurifer) is still perching quietly on the sunflower stem.
“Is that another assassin bug up above him, hanging from that flowerhead?” asks Jenny Lundberg.
There it is, an outlandish, long-legged tan bug with a narrow head and neck.
“Really!? Oh, that’s cool!” says Glenn, every word full of excitement.
For all of their drab tan camouflage, assassin bugs (Sinea spp.) are vicious predators. They hunt any small or medium insects they can find, sucking the juices out of their hapless prey. And this is the second one we’ve seen here in these few minutes of looking.
We haven’t finished watching the assassin bug when I spot one of its more-colorful relatives trying to hide behind a flowerhead. This armored, rough-textured black and yellow creature is a jagged ambush bug (Phymata sp.). Remarkably camouflaged among yellow flowers, like goldenrods and sunflowers, these bugs prey on unwary flower visitors. But here, against the green bracts, this predator is obvious. It must realize how much it stands out, because soon it flies off, in search of a better hiding spot.
Eventually we leave the sunflower patch and work our way to the edge of the water. Suddenly, Glenn sees something he’s been hoping to find. It’s large, the size of a frog, rowing gracefully away from us along the muddy bottom. It’s a giant water bug! Intent on the water now, Glenn spots another and dives for it with a tiny aquatic dipnet. He comes up with a netful of mud – and the water bug!
We all work together to rinse the mud off. Kristi Dubois carefully holds the massive insect by the sides of its abdomen, avoiding the wicked sting it can deliver with its mouthparts. Another of the wetland’s voracious predators, this bug (Lethocerus americanus) doesn’t just eat other insects. Today we’ve seen several young common garter snakes (Thamnophis sirtalis) here, their yellow and red stripes contrasting vividly with their jet-black scales. Watch out, garter snakes – Glenn says that even vertebrates this large can fall prey to the giant water bug.
As adults, sometimes it’s easy to forget how amazing life is. But being out here, learning together and being in awe of the complexity around us, I remember the enthusiasm and curiosity I had as a child. As Kelly Dix remarked today, “It’s fun to be ten years old out here.” To be out with a group of passionate naturalists, celebrating the beauty of the world around us and helping with a wetland restoration project: I couldn’t imagine a better way to spend a day.
Header photo of a giant water bug by Shane Sater