In this month’s edition of the Day in the Life series, summer student Samara takes us along as the field crew carries out lake sampling, where they monitor local lakes for invasive mussels early life forms. The view isn’t bad, right?
The highlight of this week was installing the Zebra and Quagga Mussel substrate samplers and performing mussel veliger surveys on Birkenhead Lake and Gates Lake. In order to carry out the surveys, a number of things had to be prepared or calibrated, such as: a calcium meter, secchi disk, and pH pen to test water quality, a long net attached to a cod piece and long string, and cleaning supplies like vinegar and bleach to disinfect contaminated equipment.
The sampling was done by lowering the net and cod piece into the lakes at least 3.6m deep and 1m above the lake bed; once lowered to this position the net stays in place for 60 seconds. After this period of time, the net was towed up at a constant velocity out of the water, and then quickly dipped back into the water to ensure all sediment and particles that may have attached to the net, had dropped back into the cod piece. Water drained through the cod piece via screens and was rinsed with lake water to trap all particles into the bottom of the cod piece. The concentrated sample was poured into a sample bottle; this was repeated for a total of 4 times. The samples collected could potentially contain Zebra or Quagga Mussel veligers (microscopic mussels in larval form).
This process had to be done via kayak as the depth from the dock was not deep enough. After sampling, water quality testing was done and samples were preserved for testing. Next, the equipment was sterilized to ensure we did not spread aquatic invasive species or invasive mussels from potentially contaminated lakes into non-contaminated lakes via sampling gear. This process from start to finish, although time consuming, was interesting and enjoyable. It was much different than what we typically do in the field.
We also installed two substrate samplers to the Birkenhead Lake dock. One of these will be checked monthly, and the other will be checked at the end of the season. They will be monitored for juvenile and maturing mussels simply by eye. Hopefully we don’t see any mussels on these samplers, however it will be interesting to see what else begins to grow on these apparatuses.
SSISC would like to thank the Community Foundation of Whistler for its grant that allowed to employ Samara all summer.