Ted, Kara and Michael rowed a bit offshore to collect some water and in the process of prepping to filter it, we saw that we had gathered a huge diversity of rotifers – beautiful microscopic animals that eat algae and bacteria in the lake! Frequently our water samples, even nearshore, have been a monoculture of one type of zooplankton, Epischura, but this time just about every rotifer I’ve ever dreamed I’d see in a single sample is in the water, looking healthy and happy! (Rotifer nerds – read or skip to the end – you know I’ll list them)
Having deployed Ted’s nutrient-algae experiment much more quickly than we had expected (!!), we realized that we now had some moments in between other field work to think about experimenting with rotifers. How could we be at Baikal and not use every waking moment for science? It’s a treasure trove for biologists! The water just offshore right now is full of diverse zooplankton, a great opportunity to look at a whole suite of plankton interactions under varying temperature. So, we were able to turn what might have been a 8-hour workday into a 15-hour workday today, burning images of rotifers on our retinas through microscopes! Yes, I’m excited about this!
We have been thinking about how temperature can alter predator-prey interactions, as various organisms respond differentially to temperature change. We ran some preliminary experiments overnight last night to check our variation in response and timing, and today set out to pick over 300 individuals of 4 species out of concentrated plankton samples. I reminded myself that this is one of my non-transferable skills as an aquatic ecologist – pipetting tiny moving organisms out of a slurry of other tiny moving organisms – may not be useful elsewhere but sure is useful on a day like today!
Naturally one species proved to be our nearly indomitable nemesis – the smallest Epischura baikalensis juvenile stages, a life stage of this crustacean called the nauplius (nauplii = plural). Nauplii are really fast, and a pipette under a microscope looks like a telephone pole in an earthquake as you’re trying to catch these guys!
Today is a big day with starting our lab experiment and also doing our nearshore field collections!… more to come…
OK, rotifer nerds, you have been patient (or not – if you skipped straight to the end for my rotifer list!)… Keratella, Filinia, Asplanchna, Kelliocottia, Gastropus, Conochilus, Polyarthra, Synchaeta, Trichocerca… All these were not just present but pretty even in abundance! Asplanchna had loads of Keratella and Gastropus in its guts, and everyone had eggs. A great day for rotifers.