Nothing about otoliths in this blog, but still focusing on fish and an issue near and dear to my heart. Asian carp have been in the news quite frequently for a few years now with stories ranging from their steady trek north to the Great Lakes, to people getting smacked in the head and red neck fishing derby's (do a quick search on Youtube for Asian carp, it's pretty entertaining). It seems as though these carp have become the poster child for the damage invasive species can do.
It appears now that scientists in the United States and Canada are teaming up to examine the impact these fish could potentially have on the Great Lakes ecosystem. I think this is a brilliant idea and one of the reasons I love the Great Lakes, because the lakes are shared by the U.S. and Canada there is a lot of collaboration between the two countries on how to best protect the lakes (and yes I love Canada! I love the people, the beer, the culture, curling, and of course hockey).
This issue is near and dear to myself because I spent three years working at the Lake Michigan Biological Station in Zion, Illinois after I graduated undergrad. Part of this time was spent working on the electric barrier, located in the Chicago Sanitary and Ship Canal, designed to repel Asian carp and round goby. We were using common carp as a surrogate to see if carp would be repelled by the barrier (they probably are, but there are other ways around).
Barrier or not, I am not completely sold on the idea of Asian carp being able to take hold in the Great Lakes because naturally, the lakes aren't the most productive systems. The strong effort to clean the lakes has decreased eutrophication and thus productivity. Also, the introduction of zebra/quagga mussels has shifted the productivity from the water column to the benthos, leaving little in the way of food for pelagic fish like Asian carp, as well as other fish larvae.
However, I do have little doubt that if Asian carp do become established in the Great Lakes the effects would be devastating. You could probably say bye bye to yellow perch and alewife, and without alewife there would be no salmon fishery. Not to mention the potential hazards to boaters. I am certainly interested in the outcome of studies dealing with these fish and hope that efforts to keep them form the Great Lakes prove effective.
I've always thought of yellow perch as cockroaches with fins. It seems like everywhere I've fished in freshwater I catch virtually nothing except for hundreds of yellow perch that are all too small to eat. It's hard (and a little intimidating) to think of an invasive species that could actually wipe those little bastards out.
ReplyDeleteOf course about 90% of my freshwater fishing has taken place in a handful of lakes in Vermont, so I don't know if my perch experience is really a representative sample.