Fish of the Great Lakes

Roger is also heavily in to fish biology. This is the start of a site which will hopefully cover the fishes of the Great Lakes on the north American continent. Apart from just fish photo's we now have photo's of fish collection and explain some of the survey techniques used. There is also a new page on exotics, or unwanted visitors if you wish.

Text by Roger F. Thoma.

Silver Lamprey

Ichthyomyzon unicuspis This is one of our success stories here in Ohio. As we have cleaned up the
environment, this once rare species has begun to return. The largest populations can be found in the Scioto River followed by Lake Erie. This individual comes from Lake Erie. In the Lake they are invariably attached to
the pectoral fin of a Common Carp (Cyprinus carpio). They are parasitic, so I think that's a good place for them! They are a small species, usually about 23 cm long. Unlike the Sea Lamprey, which is quite large, the Silver Lamprey does not kill its host. Sea Lamprey (and the Common Carp) are exotic species that have greatly altered the Great Lakes ecosystem.


This is Roger out having one of his late night affairs, his wife must be very understanding.

Freshwater Drum

Aplodinotus grunniens, These are three good looking specimens I captured in the lacustuary of the Black River at it's confluence with Lake Erie. Lacustuary is my term for the fresh water version of what is called an estuary in marine situations. These drum are very common in Lake Erie and most fishermen consider them a pest when on the line. They don't hold up well in the freezer and they're not considered good eating. I have found though, that if you take 'em straight home and cook 'em that night in Cajun spices (blackened redfish style) in lots of butter and canola oil (50/50) they're great! They seem to be eating lots of the alien introduced zebra mussels these days.

Editor note; Roger assures me these fish were returned to the water

Amia calva. Found primarily in wetland and vegetated environs, the Bowfin is a large ambush predator that hides amongst vegetation and strikes its prey with
lightning speed. They are very strong and my interns from the summer of 1993 (Steve White and Kelly Capuzzi) are having a hard time holding on to them.
This species has recently expanded its range in Ohio apparently in response to the damming of our rivers making them more like lakes.

These two specimens come from the lacustuary of the Grand River. You can see the front of my electrofishing boat in the background along with loading docks for
large freighters. They were hiding in a small patch of vegetation on the west side of the river.
Here's a great picture of a redside dace (Clinostomus elongatus) that I collected today. We took the picture and then returned it to the stream. It is a species of minnow that lives here in Ohio. This one is about 130 mm long. Note the large mouth and eye. This species is a sight feeder and must have clear, clean water to survive. Needless to say, it is not doing so well in our modern world. It feeds on insects and occasionally jumps out of the water to catch flying insects. Way cool!



Great lakes electro fishing

great lakes exotics