The first thing we did was fill up a fish tank with water, and put in a couple crayfish that were found in the creek. From there they were fed and taken care of for a couple weeks, before we decided to try and identify them. We pulled them out and then studied the shape of their chelae (claws), carapace (body), abdomen (tail), and tail fan. By comparing the shapes of each of these organs to a chart of species of crayfish found in southern Ontario. Our main concern was that the crayfish were Rusty Crayfish (Orconectes rusticus), an invasive species that can largely disrupt the native ecosystem. If these crayfish were of the Rusty variety, we can not release them back into the stream, where they can continue to wreak havoc on the native ecosystem. Fortunately, all of the crayfish were not rustys, so we were able to release them back into the stream, which is what we did.
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There were four crayfish that were in the fish tank. With the help of Jacob Hoving, we were able to identify them all. The biggest one was a Big Water Crayfish (Cambarus robustus), the two smaller ones were Common Crayfish (Cambarus bartonii), and the final one was a Devil Crayfish (Cambarus diogenes). As stated before, these three varieties are native to Ontario, meaning that we could release them back into the creek.
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Releasing the crayfish back into the creek