On May 3 we made the official third visit to the vernal pool we are monitoring. During this visit we are supposed to collect the frog call recorder and do the final surveys for amphibian eggs and aquatic invertebrates. At the second visit we failed to find any fairy shrimp, so I was looking forward to adding them to my crustacean life list. I was also looking forward to collecting the microSD card from the data logger we had installed on April 17 and examining two more weeks worth of data. And at the last minute I decided to bring a 24 foot-long pole and get some “aerial” photos from above the pool. By the time we left the pool to hike back to the road, I was dismayed at my lack of success at most of these goals.
by Chris Fastie • • 3 Comments
Vernal pools are little ponds which have no permanent stream entering or exiting. They fill with snowmelt, rain, and groundwater, but in droughty years they often dry out before summer’s end. These characteristics prevent fish from living in vernal pools (fish can’t get to them and fish couldn’t escape when they dry out). This allows animals with little defense against hungry fish to prosper in vernal pools, especially if they can also survive when the pool dries out.