A recent article in the Press-Register of Mobile, AL, has highlighted some work by a group of Dauphin Island Sea Lab researchers. Now, we all know of the many negative consequences of the oil spill, and they have been highlighted on numerous blogs and websites (see some of those here and here). Now I first read about increases in baby fish in Gulf of Mexico estuaries back in September. Researchers had been monitoring juvenile fish abundances for a number of years, and when it came time to conduct those surveys this summer, after the spill, it appeared as though everything was normal. Some species even were more abundant than normal. So it seemed as though GoM fish larvae had dodged a bullet from the oil spill.
Now, just this week, the DISL crew is at it again. Trawl surveys at a series of sites have yielded significant increases in fish abundance post-spill. This doesn’t mean that the oil benefited the fish. Rather, the researchers are suggesting it was the forced closure of some of the richest Gulf fishing grounds that led to these dramatic increases, strong evidence for the dramatic impacts fishing pressure has on the marine environment. And unfortunately, this unexpected result may make it difficult to truly assess the impacts of the Deep Horizon spill for quite some time.
Here’s a quote from Dr. John Valentine, from the article:
“There has been an awful lot of debate about longlining, gill netting, commercial fishing, recreational fishing, about how the ocean has been restructured by man,” Valentine said. “This was the first time we’ve ever seen such a large scale cessation of fishing.”
He said that the fishing closure appears to have demonstrated for the first time “how resilient the ocean really is if widespread management measures are applied.”
However, the GoM is hardly in the clear, and all the researchers involved are quick to point out that this increase isn’t necessarily good news. Many fish and fish larvae were likely lost in the spill, and it will taking longer to discern these effects with the dramatic impact the fishing closure had on the data. Either way, it is an interesting story, and certainly one worth thinking about.