• EAHCP Steward

They Get by with a Little Help from their Friends

EAHCP Steward - September-October 2018 - www.EAHCPSteward.org

Dr. Ely Kosnicki, a senior invertebrate ecologist with BIO-WEST, is a serious scientist and has spent many years learning about freshwater invertebrates in various parts of the country. And, after an hour-long interview in discussing the endangered dryopid beetles found primarily in the Comal Springs system, you would be certain that you had just experienced an advanced aquatic biology class he has taught in the past. But, then you learn that he calls the two-dozen or so six-legged creatures by name…Wilma, Bonnie, Clair, Alex, Omar and so on…and you understand Kosnicki is enjoying this important ongoing study as well.

“Well, if I had been a little quicker on my feet, I probably would have come up with some clever names for the beetles, like John, Paul, George, Ringo, Yoko Ono and such,” Kosnicki deadpanned. “We keep meticulous records of each dryopid we bring from the springs into the lab, and so we concluded that names are a little more friendly than numbers.”

Dr. Ely Kosnicki at the San Marcos Aquatic Resource Center lab.

Studying the dryopid beetle is all part of the Edwards Aquifer Habitat Conservation Plan (EAHCP) refugia program. Researchers are learning as much as they can about this species and will hopefully be able to propagate them in the lab and watch the larvae grow into adults. The refugia program is designed to enable the EAHCP team to hold endangered species in captivity in order to reintroduce them into the wild if a natural disaster ever decimated the species and their habitat.

This beetle was first discovered in spring outlets in 1987, officially described in 1992 and declared endangered in 1997. But, up until the current study led by Kosnicki at the beginning of last year, scientists couldn’t tell the males from females and really knew very little about how they live. However, in just the past 10 months, Kosnicki’s team has learned a great deal about these invertebrates.

“These are tiny creatures about the size of a grain of rice,” Kosnicki explained. “So finding them in the wild was not easy. We knew they live in the spring systems, and that’s where we started looking. Cotton seemed to be the lure of choice when we began, but we learned that they really liked the biofilm that grows on wood and so we had success just searching various types of wood at spring openings. Our current permit limits the number of specimens we can actually take out of the wild in a year. Plus, if we find a group of beetles, we’re only allowed to move half of them to the lab. Needless to say, capturing specimens is a time-consuming task and in the end we are only left with a handful of specimens to work with.”

Kosnicki was able to determine the sexes of the dryopid beetle rather quickly by observing mating habits and then finding definitive markings on the abdomens of males and females. Sometimes, the sexes in various species will have size differences, but in this beetle’s case, size was not a factor. Additionally, Kosnicki and research teammate Eric Julius had to recreate the type of living environment in the lab that the dryopid beetle was used to in the wild. They used small containers with flowing well water from the Edwards Aquifer on site, dropped in some rocks, leaves from various trees found near the springs and added some wooden dowels that the beetles liked to feed on. The dowels are wrapped with a bit of cotton in order to catch any eggs laid by the females. As beetles are brought into the lab, the team pairs a male with a female and puts them into one of the containers. A few weeks later, Kosnicki and Julius will remove the cotton, use a microscope to check for eggs and move any eggs to a rearing chamber.

“The big news in the course of the study is that six of the eggs, from a total of about 80 eggs laid so far, have now hatched into larvae,” Kosnicki stated. “We will be watching those larvae very intently to learn how they react to the environment they are in, what they primarily feed on and ultimately whether they grow into adults.

“We’ve really made some important strides in getting to know these tiny endangered creatures. And, obviously, we’re hoping to come to know much more about the larvae as they grow into adults over the next year or so.. And while this can be tedious, detailed work at times, its very exciting when we learn something new about them. We’re all anticipating the day we can name an adult that has grown up in the refugia.”

They should probably grab the Beatles’ Sgt. Pepper soundtrack and play “With A Little Help From My Friends.,” too.