Saturday, July 17, 2010

Crayfish monitoring

Crayfish monitoring was part of the class that I recently took at the Mountain Nature Camp in Terra Alta, West Virginia. The weekend was devoted to arthropods and their collection for scientific research.  The program was designed for Master Naturalists and teachers. The idea behind it is that the Master Naturalists like me would learn these techniques and help in collecting for the state in their efforts to document the health and distribution of crayfish.  The teachers were there to do the same but with an added twist of getting their students involved and excited about natural history. Hopefully one day one of those students will become a professional biologist and work in WV to save our environment.

The class was in two parts, one was on crayfish and the other on insects. Below are a couple of the graduate student researchers showing us how to collect in a net. First you pick up rocks and shoo the crayfish into the net.

Next you do a little dance when your back gets tired of bending over.  Really, you do just about anything to get them into the net...

...and here is the catch!

This Ebony Jewelwing seemed to look on with amusement.

Below is Zac Loughman, a crayfish expert and the guy who was doing all of the teaching. He has been doing a study for a couple of years now document new species for WV and discovered that some are no longer here. Each  person in the class is required to make collections in their counties and send them to him.

Here are two of the same species, Cambarus dubius, one male and one female.

Later that night we went for a walk down a country road and looked in the side ditches to find more crayfish. I have forgotten what species we found...sorry.  For the last couple of years Zac and his grad students had been lurking about looking for crayfish poised at the edge of their holes and grabbing as best they could. But tonight they were documenting the effectiveness of a new method of collecting.

The strategy is a lot like fishing. They use a hook and bait and tangle it in the hole or just in front of the crayfish.  I think they were having 100% success rate because everyone they saw grabbed the bait and while the crayfish was distracted Zac grabbed the crayfish.

You can see above how the crayfish don't actually get the hook in their mouths but just hold onto it like a skewer and munch the bait.  This guy didn't even stop eating while he was measured.

Here is Zac with his grad student taking measurements and writing up their field notes. You can see the pleasure on their faces doing this field work.  Next it will be my turn to collect with a little help from my friends.

Enjoy more at Watery Wednesday.


2sweetnsaxy said...

What an interesting post and photos! I can do without the craw fish though. LOL! I think I'd freak out if I accidentally stepped on one.

eileeninmd said...

I remember walking thru streams as a kid looking for crayfish. We could always find some hiding under the rocks. Wonderful post.