Revisiting Creek & Vernal Pool Collections

Since our visits to the creek and the duck-weed pond late last year, I've kept a container of the water with some of the aquatic plants in it as a sort of aquarium with whatever creatures are living in it. I covered the containers and left them outside for about 2 months. 

Additionally, I collected a handful of dry vernal pool soil and added dechloronated water to it to see what might appear. This is our third dry year of drought in California and it makes me wonder what can survive these conditions and how. 

A couple nights ago, I brought these samples in and spent several hours looking at them under a microscope. Here is a video of the creatures I found in the drops of water and bottom debris on a standard size glass slide. You can see them with the naked eye and, for the record, none of the creatures I've been able to identify, including the flatworm, are parastic. I have, however, seen leeches in the creek so that's not to say there isn't anything parasitic there. 

Here's a closer look:

Clam Shrimp (conchostraca)

Unidentified hairy sac
The similarity in shape makes me wonder if it isn't a molt or an egg casing of the clam shrimp

Aelosoma

 

Cyclopoid Copepod

This is hardly visible, but it is a clear worm - unidentified

This creature, a gastrotrich, was found in the vernal pool soil that I added water to. According to Encyclopedia Britannica, gastrotrich lay "opsiblastic" eggs, which remain inactive for long periods and can survive dry and freezing conditions. Certainly explains things doesn't it?

gastrotrich

Here is a video showing the movement of these creatures - some are squinchy, some are frenzied, some are seeking - all very interesting and unique. A whole world we obliviously step right through on our hikes!