Invasive Species in Lake Tahoe
Hello. My name is Andrew Tucker. I'm a graduate student in the zoology department at Miami University and I work in Craig Williamson's lab. One of the primary interests of our lab is to study the effects of ultraviolet radiation [UV] on aquatic organisms. So what this generally means is that we get to work where the sun shines and water is blue- places like Lake Tahoe here in the Sierra Nevada Mountains. Lake Tahoe has been my laboratory for the past 3 summers as I investigate whether or not ultraviolet radiation can control the spread of warm water invasive fish species in the lake. Now, these species, like largemouth bass and bluegill, were introduced into the lake about 20 years ago but are currently constrained to the southern end of the lake which is rather more developed. But there is concern that, if these species should spread throughout the lake, there could be severe implications for the native species of fish, cold water trout and some of the native minnows. So what we do is conduct experiments to test the relative UV tolerance of these native minnows vs. the largemouth bass and bluegill larvae. And we travel around the lake to a number of sites to assess UV levels in each of these sites ... a function of water clarity essentially ... and we collect other data as well, like zooplankton abundance and species composition so that we have some sense of food availability for these fish species around the lake. Ultimately our goal is to develop a UV threshold or, in a sense, a water clarity threshold that can be used by lake managers to control the spread of invasive warm water fish. What we hope is that, as they say around here, this is one more reason to, "Keep Tahoe Blue."