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Science/Tech See other Science/Tech Articles Title: Why are Chesapeake rockfish sick? Rockfish with the disease mycobacteriosis can develop lesions and have their scales destroyed. AP/KATHLEEN LANGE OXFORD, Md. -- Biologist Larry Pieper is wearing waterproof overalls and giving dozens of bass from the Chesapeake Bay a tabletop inspection. He's not surprised by what he sees -- many of them look sick. Pieper is part of Maryland's first effort this year to take a new look at a chronic wasting disease in striped bass, commonly called rockfish or stripers. Mycobacteriosis, also known as "myco" or fish handler's disease, can slowly eat away at a fish's scales. It can leave nasty lesions and kill the striped bass, the hallmark fish of the Chesapeake Bay. Beyond that, scientists don't know enough about the disease to know how worried they should be. "We know a whole lot of nothing," Pieper said after examining 80 striped bass, noting lesions and little brown specks that suggest the bacteria are present. Myco is usually harmless to humans, as long as anglers wash their hands after handling infected fish. However, scientists are startled by the bacteria's spread through the region. State biologists in Maryland and Virginia say that about 60 percent of the bass in the Chesapeake, where most of the East Coast's striped bass come to spawn, are now infected. But scientists aren't entirely sure whether myco kills all striped bass that get it, or whether some striped bass recover, and why. It's not clear how myco spreads, nor why the disease has increased sharply in recent years. It could be that there are simply more bass in the bay. After overharvesting nearly wiped out the striped bass, a fishing ban in the 1980s led to a remarkable rebound in the species, with fishing now allowed. Another suggestion is that more bass are getting sick because they're weakened by low food supplies, or because low oxygen levels in cold water drive them to warmer water, where they're more vulnerable to disease. "When we started, there was lots of anecdotal information, lots of impressions, but nobody knows" exactly how the disease behaves or how it affects the fish, said John Hoenig, a researcher with the Virginia Institute of Marine Science in Gloucester Point, Va. Bounty hunters To find answers about the bacteria, biologists are trying a new method to learn about it. Maryland's Department of Natural Resources, along with a federal research group, started a new kind of tagging project this spring. The research differs from traditional tagging because anglers are asked not just to call the number on the tag and report where and when they caught the fish, but to keep the fish on ice. Fishermen who do so get a $20 bounty, plus authorities will come pick up the fish. On a tagging trip last week, 11 Maryland biologists tagged and examined 80 fish. Pieper looked at each fish and announced its condition to a notetaker -- "The left side is clear," he called, or, "We have healing on the right-side fin." Then the fish went to a white piece of wood for several photographs on each side, plus close-up shots of any lesions. After a few moments on board, the tagged fish were tossed back into the Chesapeake. Scientists hope that when anglers catch the tagged fish months or years from now, they'll be able to match the fish to their original pictures. "Some of the fish that didn't look so good, they may come back in a year and be healed. We just don't know yet," Pieper said. Economic impact Virginia has been doing this type of work for two years, tagging 6,700 bass since 2005, but this is Maryland's first year joining the effort. The research could yield lucrative findings. Recreational fishing in Maryland is an industry valued at more than $300 million a year, by state estimates. Unsightly lesions on striped bass and public worries about catching fish handler's disease can harm charter boat captains and commercial fishermen who depend on the fish for their livelihoods. The research could prompt fishery managers to cap harvests or make other arrangements to help the population thrive despite the bacteria. It's a new approach for officials used to considering only catch data when surveying a fish population. "Historically in fisheries, fishing is the problem," Hoenig said. When disease hits, he added, "We're sort of unprepared for that." Figuring out clues DNR biologist Kevin Rosemary, photographer for the striped bass, said that the research could prove valuable even if most fish don't get caught and called in. Dead fish are usually gobbled up quickly by other critters, so if the returned fish in Maryland's study were more likely to be disease-free when tagged, that could mean the sick fish were more likely to die. "We're hoping to learn if fish die of myco or not," Rosemary said. He said Maryland hopes to tag 1,000 striped bass this year, some in the spring and then again in the fall. Already the effort has yielded some clues. Hoenig said that when Virginia started its tagging, some people were critical because myco is always fatal in captive fish. Turns out, striped bass in the wild can live years with the bacteria, some plump and alert despite being mottled with lesions. "Some people said it was silly because we're going to tag them, and then they're all going to die," Hoenig said. Now, as scientists learn more about how the bacteria affects the beloved striped bass, the next step could be clues for how to deal with mycobacteriosis. "It's hard to convince people to take action if we can't demonstrate that there's problem," he said. WANTED: STRIPED BASS WEARING GREEN TAGS WANTED: Striped bass, also called rockfish or stripers, with a small green tag to report the catch. THE CRIME: Scientists want to know more about mycobacteriosis, a mysterious wasting disease that now infects more than half the Chesapeake Bay's striped bass. Not all the tagged fish have the bacteria. But healthy fish are wanted, too, to see if they've stayed healthy since Maryland biologists tagged them or if they had the bacteria but recovered. THE EVIDENCE: Some striped bass with the bacteria have mottled scales, or even nasty lesions. Some infected fish have tiny brown dots on some scales. Some infected fish show no outer signs of disease. The bacteria is usually harmless to humans, and if your poor hand-washing skills lead to an infection, the disease is easily treated with antibiotics. In rare cases of untreated mycobacteriosis, arthritis-like symptoms can result. THE REWARD: Anglers get $5 for calling in a catch, or $20 if they keep the fish on ice for scientists to retrieve. Source: Maryland Department of Natural Resources
Poster Comment: When I was a kid my dad would wake my brother and I in the middle of the night so we could be on the fishing pier at Ocean View before sunrise. This pier at the mouth of the Chesapeake bay is one of my fondest memories because it wasn't unusual to catch 100 pan sized spot and croaker, give 60 away and take 40 or so home for a breakfast fish fry. If you've never eaten a fresh (never frozen) ocean fish then you're letting the best of life pass you by. But, in the mid 1970's a corporate type was convicted of the crime of dumping Kepone (a poison) into the James River which then proceeded to poison the fin and shellfish in the bay and leading to a years-long moratorium on their harvest. This was the first time someone went to jail for an environmental crime, and the impact on the bay and fishing was immediately obvious. Gone were the days of pulling up young pan fish two at a time, and my soul and the bay are forever damaged. They still monitor the waters near the bridge tunnel (connecting Hampton and Norfolk) because of the very real threat that hurricanes may release sequestered Kepone. The mighty striped bass is also a favorite fish here in DE river, where the migration alternates with the Chesapeake bay depending on unknown factors that determine the fish's choice of routes every spawning season. The Chesapeake bay and the Delaware river are connected by the C&D canal on the north end of the bay, so a problem with Chesapeake bay rockfish is a problem with Delaware rockfish. What I wouldn't give to have lived when the Dutch landed here and the English landed in Jamestown, when clams were so thick that one could rake them from the clear waters all day every day non stop. My soul is in agony when I read these stories. Words fail me beyond a mere account of the evidence of a crime for which there is no suitable punishment. And, when Native Americans say that we whites have destroyed the land I have no answer....
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#3. To: HOUNDDAWG (#0)
I have to agree...
I have to agree... none at all bump.... I'm not one to beat up on white folks or embrace the poor, downtrodden Native American for the sake of earning the favor of young, braless hippy chix. (anymore) But, when it comes to my beloved Chesapeake bay, the C&D canal where my dear father ran his seagoing tug to and from Edgemoor, DE and/or Philadelphia and our home in Norfolk, the Delaware river where I live now (and where we recently defeated a Dupont Co. plan to dump partially neutralized VX nerve gas into the river not five miles from here) and when I see the warning signs that advise consumption of no more than 8 ounces (one fish fillet) a year for non pregnant consumers of the fish taken this far up the river, well, it just makes me want to beat the living DAWGGY poo out of someone. One mile away is the Christina river (named after the Queen of Sweden) and around 1900 the industrial dumping began there, and it is now a major SUPERFUND SITE. The remediation cost multi millions, precludes any future dredging or consumption of fish from the once pristine river, and if G_d is watching then he knows who continued the dumping even after being made aware of its consequences.
LOL Did grad time on the Chesapeake also with the CBF and a good friend is head of it... biggest pollutants...~90% are from your unregulated farm pollution coming from your "good old timey" Amish and their farming practices coupled to a lobby PA does not want to deal with. Period! The Susquehanna is the major input into the Chesapeake Bay which has been dead for three decades that I know of. From far north of Shamokin Dam into New York State and through Pennsylvania, farmland drains unimpeded into the river. Bottom seining does not help the bay as it is like a lawnmower cutting everything from the bottom up. Nor do the airplane-directed menhaden fleets out of Fleetwood VA do the system any good. The primary problem of the Chesapeake is oxygen deprivation caused by nitrates and phosphates from Pennsylvania uneducated and allowed farming practices which cause an algal/planktonic bloom which first makes the water less transparent and kills the eelgrass etc on the bottom which in concert with the plankton cycle all dies at once, sinks to the bottom, decays, thus sucking up all the oxygen which kills the fish, crabs, oysters, clams etc and the young....or if not killed they find little to eat since the eelgrass is gone thus no oxygen replenishment. This was and is the problem then and now. The guts to change are lacking in the politicians who know what I say here is true and have not and will not do anything constructive about it and continue to pay their mouthpieces and hired " scientists" to spout garbage always sounding like... It ain't OUR fault...its them dirty old .... ( pick one, whichever whipping boy is popular at the moment to save the pols sorry asses).
Period! Perhaps your study was intended to ignore the 4 billion dollar per year chicken industry on the DeMarVa peninsula. Tyson has enough pull in my state guarantee a chicken-friendly DNR. And, any attempt to to make the growers pay even partially for the remediation of the millions of tons of chicken manure is met with howls of protest which our general assembly doesn't ever want to hear. Edit: it should come as no surprise to anyone that the one group that doesn't grease politicians or participate in the political process is blamed for the whole mess...
No, I am not forgetting that. However: 1. Half the DelMarVa rivers flow into the Atlantic, not the Chesapeake. 2. All the DelMarVa rivers together are a bare fraction of the Susquehanna input. 3. The Susquehanna remains the major source of pollutants, and they are famnland pollutants, that poisoned the Chesapeake bay by 1970.
I don't want to shoot from the hip so, I just say this for now. The delicate estuaries of the bay still produce an abundance of blue crabs, and the fishing on the Susquehanna Flats is still wonderful. When has a red tide or algae bloom resulted in a Chesapeake bay fish kill?
all the time BTW the process is called eutrophication . Wiki may have a section on this. I have not looked. You may well find it very interesting.
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