The Hines’s burrow choice is a strange one, but it’s not totally unheard of; some fish in the Everglades depend on the wallows made by predatory alligators. And in some ways, the crayfish is a good landlord. It burrows up to four meters below the surface, creating elaborate burrow systems that stay cool and damp in the summertime and warm in winter — essential for the Hines larvae’s survival. The crayfish also keeps the burrows nice and tidy, feeding on dead and live plant material inside. Soluk says one reason the pair can coexist may be because the cramped space prevents the crayfish from moving its arms to nab the larvae. No one knows for sure. The only certainty? “For eight months every year,” he says, “they’re living with the enemy.”
When Soluk determines the burrow adequately flooded, he covers one hole with his hand and into the other inserts the first hose. An assistant holds the second hose over a catch net she’s stretched over an empty bucket. A third assistant stands between them on the plywood platform and pumps away.
In seconds, the water — and its murky contents — slurps from the burrow and into a giant bucket. The assistant works the sagging net like a sieve until she has to strain it, cup by cup, into a shallow tray. With the patience of a woman panning for gold, she tilts tray after tray back and forth, fingering the contents of each for its prize.
And then she finds it: A Hines larvae, about he size of a walnut, covered in hair and, save for six spindly legs, looking much like a chunk of muck itself. “I always say they look like a tennis ball after a dog’s through with it,” says Soluk.
The crew searches through the rest of the slop. No more larvae are found. No crayfish either, but Soluk’s not surprised. Ironically, occupied burrows usually reveal the most Hines larvae.
He says he’s found as many as 74 living in one occupied burrow. “It’s a strange and complicated relationship,” he says, and so far, a mystery odonatologists can’t explain.
Two stone lions flank the front door to the University of Michigan’s Exhibit Museum of Natural History. Inside, the dome ceiling of a giant rotunda looms overhead, under which grand columns stand and sweeping staircases loop visitors from floor to floor. On the second floor, opposite the route to the prehistoric life exhibit, there is a nondescript set of doors that lead to a long, white hallway lined with dozens of closed wooden doors. At its end, through another door, a stairwell, and another door, is a second long, white hallway. It’s home to more than 4.5 million insect specimens collected from around the world and one of the largest collections of dragonflies in North America — 600,000 specimens. In terms of diversity, that’s even more than the Smithsonian.
Mark O’Brien is collections coordinator of the insect division at the university’s Museum of Zoology and organizer of the Michigan Odonata Survey. A guy whose long, curly ponytail belies the professorial gray of his bearded chin, O’Brien says he had never been particularly passionate about dragonflies — he’s a wasp man from way back — because the few dragonfly field guides that existed as recently as 30 years ago were so poor, trying to identifying the creatures was maddening.