LAKEPORT— Carp, long an imported fish food, is now frequently considered an invasive species in many parts of the United States, so the Board of Supervisors has authorized an allocation of Lake County funding to purge this non-native pest to help the local Hitch (minnow) population thrive.
Greg Guisti, of the Lake Co. Fish and Wildlife Advisory Committee explained Carp are quite aggressive toward other species. They characteristically kickup significant sediment sometimes digging a foot deep in a lakebed, and in the process stir up large amounts of phosphorous, which in turn circulates a bacteria harmful to other fish and local habitat. One way of keeping Carp at bay is to track its whereabouts with radio-tagging. Radio-frequency identification (RFID) uses electromagnetic fields to automatically identify, and track tags attached to objects or animal. An RFID system consists of a tiny radio transponder, a radio receiver and transmitter. When triggered by an electromagnetic interrogation pulse from a nearby RFID reader device, the tag transmits digital data, usually an identifying inventory number, back to the reader.
Working with Guisti, biologist Luis Santana noted they tagged 30 carp last year with the radio telemetry process which they use to keep tabs on the carp location. The most efficient method to monitor carp is flyovers in aircraft above Clearlake. “We want to do flights a month before spawning season (Nov.- March), so we want to do a flight in winter, possibly spring and even in fall,” he said. At $1,800 per flight, total cost will be $5,400. “It’s good use of money,” said Guisti.
Santana then clarified, “What we have seen with radio telemetry, (invisible, silent electromagnetic wave to ID location) is that carp eat a lot and are rather belligerent. So, we’ll move everything out of the path of the carp, because they’ll eat fish eggs and everything the Hitch normally eat.” And Guisti pointed out the ripple effects of environmental damage. “There’s a level of standard reached, when more carp are present that creates an ecological and economical concern that is two and a half times the threshold of the habitat (in Clearlake).” The idea is to remove the carp. Yet evidence indicates carp has been in Clearlake over a century. In fact, there is evidence they were introduced by a single individual during the late 1880s.
District 4 Supervisor Michael Green noted it has been a really good year with the abundant winter and spring rainfall, but wondered the best way the county can do resource planning. And he pointed out that resource documents that establish the limits of Hitch habitat could be outdated. Guisti concurred and added they needed to start a real time trend analysis in order to understand the relationship between flows, temperature, water quality, so people can make decisions.
Green then elaborated on that concept recommending stakeholders continue to track Clearlake habitat, continue to record data to store it in some type of portal in order to make it accessible so the county can review it for a pending programs. The best example he has seen was in the Public Trust Ordinance recently passed by Sonoma County.
“What the Public Trust Ordinance does, it has a very detailed GIS (geographic information system) capable map,” he said. “It follows a subset of a county as a whole and focuses their efforts in these public trust areas where fish congregate, and the map shows these areas … it’s helped in Hitch recovery efforts and probably in land use planning and project approval.
Guisti agreed it’s doable and a very useful tool. And he noted, the primary purpose of the Fish & Wildlife Advisory Committee is to advise the BOS on how to spend fish and wildlife fine money. A portion of the fine tickets a warden issues is allocated to a separate account to dispense on a pending project.
“Right now we have $40,000, and we’ll allocate about $20,000 for projects each year,” he said. And he noted the Robinson Rancheria and the California Department of Fish and Wildlife will receive training from a a well-seasoned group from the Midwest to assist in the radio-tagging of the carp.
What a difference a year makes, Guisti concluded regarding the winter rains as weather conditions made optimal spawning conditions.
“It not only provided an opportunity for adult fish to come up stream and spawn but an opportunity to incubate, hatch so juveniles can move back to the Lake,” he said. ”
Equally important, the Lake came up 10 feet because of the rains. And fish were recorded in all the creeks that have supported the watershed system.
