Jellyfish Gone Wild — Text-only | Flash Special Report
Here in the northern Gulf of Mexico, I think it’s pretty typical everywhere, at least in coastal environments, is that when you get a good, you know, well-established bloom of jellyfish and they start accumulating in these aggregations close to shore, and you know, it depends a little bit on the species, but if we’re flying over on an airplane, you can go the entire coastline and see repeated, you know, just pink aggregation after aggregation of, you know, just thick jellyfish. So, they can go for miles and miles, you know, hundred miles long. In the thickest packs, it’s – there’s more jellyfish than there is water so, you know, you can, you know, as many jellyfish as you can squeeze into a cubic meter, that’s what the density is so it’s easily in the 50 to 100 animals in a cubic meter of water when they’re at their thickest.
Here in our waters we’ve got anything from old bridge rubble, when a bridge is taken down, they’ll take the bridge out and dump it or we sink whole ships. Recently they sunk an aircraft carrier off of Pensacola. We have fields of World War II era army tanks and it used to be that pretty much anybody could take anything they wanted, as long as they made sure it was, and had it permitted, that it was drained of oil and gas or anything else that might leak into the environment, but they can take anything out and put it into a specific area, but dropping it so we have barges of shopping carts and newspaper – old newspaper vending machines and, you know, people would take their old cars off, you know, just dump all this stuff out there so it’s this haven for fish, but we’ve done this without really appreciating what we might have done to the environment in terms of bringing in habitat for things that otherwise wouldn’t be there. So, and within this community of things that otherwise might not be there might be whole suites of jellyfish polyps and other things that otherwise wouldn’t have a home to reside.
Part of their life history is always to be numerous at times if we’re talking about medusaes, to be numerous at times. So, these blooms, they’re not really oddities but what happens when you start adding more nutrients or you start removing too many fish or you start adding too much structure in the ocean, or you do all these things or even, you know, increasing the temperature of the water, you do all these little things, each one by themselves seems to be able to nudge jellyfish to being more abundant. You add all of them together and they’ll do a very good job of bringing jellyfish numbers up and so we can see that jellies are kind of sitting on this, you know, on this threshold of ecosystems that if ecosystems are, you know, healthy, then jellies will sort of do their normal thing. They’ll go about the --- make blooms, they’ll go about their happy jellyfish lives, but if you nudge the system towards the more perturbed side, the jellyfish will take off and so we do sort of think of jellies as being that, you know, that canary, that bellwether of change, and I think it’s an appropriate comparison.
NOAA Cordell Bank National Marine Sanctuaries
Sean Colin, Roger Williams University, and John Costello, Providence College
Dauphin Island Sea Lab
Michael Dawson, University of California, Merced