Ongoing water creature collection (moving water)

TravisH · Post by **TravisH** » Sat Sep 05, 2015 11:07 pm

Good afternoon all,

I have just recently got my adapter to connect my Microscope into my digital camera and am enjoying starting to get images of various things. The last one I got was from a local dam, and I was a bit disappointed as (the image is below) after some filtering of water, and re-suspending the filter collection I didn't find as much as I was expecting.

Microscopy Art by Trav H, on Flickr

I have a few creek's near my place which I would be able to get to fairly easily, and I think anything I put there would be unlikely to be moved, but I am curious if anyone has done anything like that where a filter, tube or whatever is placed in a slowly moving creek to allow stuff to be caught in the filter, or tights or whatever is used.

The reason i ask is that, whilst it could be my collection my above image I collected from a fairly 'active' dam, which had the combination of smell, yellow / brown tinge and the likes but i didn't have to much luck to it.

Is it likely just my collection, and I should try the collection method suggested by Krebs with the rectangular baking dish, or is there another way to do it making use of moving water streams and the likes?

Appreciate any feedback.

Charles Krebs · Post by **Charles Krebs** » Sun Sep 06, 2015 6:39 pm

Trav,

You will often find that collecting samples from the clear, moving, freshwater in a stream or creek is pretty unproductive.

Try scraping and collecting some detritus off of rocks or sticks at the edge of the water (or off of any "slippery" rocks in the water flow). Collect a sample of aquatic vegetation that may be along the shoreline, especially if it is in a quiet area with minimal water flow (get a little of the bottom sediment as well). You'll find plenty of things to study under the microscope.

I am not sure how you are working once you get home. It's usually best to go over your samples with a stereo microscope. Using a pipette, move potential subjects to a smaller petri dish or something similar. Make up a wet-mount with either a specific targeted subject, or with some material that looks particularly interesting. You can then work on the higher magnification compound scope.

TravisH · Post by **TravisH** » Sun Sep 06, 2015 7:34 pm

Thanks for the tips, will have a look at the creek as I think there should be heaps of rocks that have slime and moss and the likes on them.

My process at home is typically to try and concentrate the water (e.g. through a filter) and then to resuspend that and do a wet mount on a slide as I only have the one microscope which is a pathological microscope rather than a stereo / dissecting microscope.

TravisH · Post by **TravisH** » Mon Sep 07, 2015 8:19 pm

on a slight tangent, I am trying to improve my identification skills. Since I have altered the microscope settings I am not getting as clear color which makes the longer stranded items harder to identify, but would I be close in assuming that the identification is likely to be:

Pond scum - Gamopyta, and
Green algae

It did come from a stagnant pond which is essentially the overflow of another dam.