Jellyfish, overfishing, and the dead zone

Our household traveled to Alabama last week for my wife's family reunion. We spent most of the time at condos at Orange Beach and had a very good time. On Friday and Saturday we went into the ocean, and our son got a jellyfish sting each day. There were no side effects except for some temporary pain. (I stepped on one and it squished underneath my feet. Yuck!)

However, as there were many kids and adults fishing jellyfish out of the water with nets, it piqued my curiosity as to why there were so many. I did a news search earlier in the day and found a couple of interesting articles.

The first article from the Herald-Tribune.com site, "Are jellyfish a harbinger of dying seas?" proposes the hypothesis that the proliferation of these creatures could induce the seas towards a more primitive state. Robert Condon, a researcher at the Dauphin Island Sea Lab, published a paper in the Proceedings of the National Academy of Science that looks at the relationship between jellyfish blooms and how they fix carbon in trophic levels not readily accessible to other creatures.

The reason I am posting this in my blog--after a two-year absence--is that two possible causes for the proliferation of jellyfish are the overfishing of predators and the large annual anoxic dead zone in the Gulf of Mexico. "Jellyfish thrive in disturbed marine ecosystems, from dead zones to seabeds that have been raked by trawling nets," according to Jon Bowermaster in "Jellyfish return to the nation's coast."

Overfishing as an issue of concern for the future of food is obvious. The dead zone due to the excess of fertilizers washed into the Mississippi River and into the Gulf of Mexico is an annual concern and indicates long-term problems with how we manage the lands on which we grow food.

I would like to delve into this topic in more detail later, but I wanted to write this brief synopsis as an new area of inquiry.