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Date: Tue 28 Jun 2011
Source: New Hampshire Sentinel Source [edited] <http://www.sentinelsource.com/news/local/a-fish-death-mystery/article_d40b0446-82d2-592c-9ede-9b9278bf940b.html>

There's a mystery brewing on Spofford Lake [New Hampshire], where hundreds of fish have turned up dead over the past 2 weeks.

Officials have no leads on the potential cause of the deaths, spanning several species of fish that have been washing up on the lake's shores since at least 16 Jun 2011, officials said Monday [27 Jun 2011].

"This time of year, there's typically nothing to be concerned about,"
said Gabriel Gries, a fisheries biologist for NH Fish and Game in Keene. It's actually quite common, Gries said, to find 20, 30, even 50 dead fish washing up this time of year due to natural causes.

"The fish are stressed from spawning; they're guarding their eggs; making nests," he said. "Then all of a sudden there's 3 or 4 days of really hot weather, which raises the temperature of the water, and the already stressed fish expire."

But this year [2011], there are a few unusual factors involved, Gries said. "The interesting thing here is that it's not 1 or 2 species," he said. "We've found yellow perch, bluegills, northern pike, large and small mouth bass, and bullhead catfish."

The discovery of dead bullhead catfish was particularly alarming, Gries said, because that species is normally quite resilient.

Fish and Game in Keene fielded nearly 30 calls about the dying fish since last weekend [25-26 Jun 2011], said executive secretary Pat B Hersom, which gave Gries reason to suspect something abnormal was occurring. "We went out and scoured the lake for any kind of sign of what might be happening, but found nothing," Gries said.

Fish and Game officials collected approximately 8 dead bluegills and one bullhead catfish, which were sent to the US Fish and Wildlife Service's Fish Health Center in Lamar, Pennsylvania, Gries said.

Officials hope to hear from the center about the test results later this week, Gries said. State officials are "in a holding pattern"
until they learn more about the results, said Walter M Henderson, a biologist for the NH Department of Environmental Services.

"My 1st thought when I heard about it was that someone was using pesticides that got into the lake," Henderson said. "But (Gries) said it's not a point-source, so it's not limited to one part of the lake."

Based on the information at hand, Henderson said they're likely looking at some kind of fish disease.

Spofford Lake Association President Bayard F Tracy has been a resident on the lake since 2006, and said he's never seen anything like it. "This is a class A lake," he said. "It's very clean. Right now the lake looks as clean as it's ever been. Now we have a situation that's A, unusual, and B, continuing.

"I've gotten a lot of calls and emails (from concerned residents and association members)," Tracy said. "Everybody's looking for an answer."

The appearance of tail or fin rot on the fish carcasses could provide some hint as to what the problem is, but there's no telling yet whether those symptoms occurred before or after the fish died, Gries said.

Tracy said the association tries hard to help people understand how their actions can affect the health and quality of the lake. "We tell them," he said. "Chemicals, lawn fertilizers ... the lake sits in a bowl, and it's spring-fed with a relatively small outlet, so it doesn't turn over a lot. Anything that gets in there will stay a while."

A longtime Spofford Lake resident said this year's [2011] fish die-off is the worst he's seen in 30-plus years. "My guess is it's 10 times more than normal (die-offs)."

Gries couldn't say exactly how many fish have died so far, but they number in the hundreds.

The association pays to have the lake water-tested 3 times a year, Wood said, with the most recent test having occurred 23 Jun 2011, according to Tracy. Those test results could be available as soon as next week, he said.

Meanwhile, the annual Independence Day fireworks [4 Jul 2011] display will proceed as planned Saturday [2 Jul 2011], Tracy said. "We also have the parade of boats on the 4th, but I don't expect either event to be affected by this," he said.

When it comes to swimming and fishing, officials said it's too soon to put up any caution flags. "It's up to individuals what they want to do," Tracy said. "I'm not going to push the panic button personally, not until we have the facts."

[Byline: Kyle Jarvis]

Communicated by:
HealthMap Alerts via ProMED-mail

[While they wait on official tests to help determine the cause of the die-off, they need to be picking up the bodies of the fish that wash into the shore of the lake. If left around the shore the dead fish will be a perfect medium for botulism and then the problem could escalate. We look forward to the test results. - Mod.TG]

[Brown bullhead catfish (_Ameiurus nebulosus_) photo:

[Spofford Lake can be located via the HealthMap/ProMED-mail interactive map at <http://healthmap.org/r/0*fU>. - Sr.Tech.Ed.MJ]

[see also:
Die-off, carp - USA (03): (MI) 20110629.1976 Die-off, carp - USA (02): (MI) 20110625.1948 Die-off, carp - USA: (MI) 20110622.1907 Undiagnosed die-off, fish - USA (02): (GA) columnaris 20110528.1641 Undiagnosed die-off, fish - USA (GA) 20110526.1599 Undiagnosed die-off, fish - USA (05): (OH, Lake Erie) walleye
Undiagnosed die-off, fish - USA (04): (WI) crappie 20110508.1421 Undiagnosed die-off, fish - USA (CA): domoic acid susp.
Undiagnosed die-off, fish - Kenya: (Mara River) 20110218.0535 Undiagnosed die-off, fish - New Zealand: RFI 20110112.0136 Undiagnosed die-off, fish - USA (03): (AR), RFI 20110107.0085 Undiagnosed die-off, fish - USA (02): (MD) 20110106.0058 Undiagnosed die-off, fish - USA: (AR), freshwater drum 20110104.0035] .................................................sb/tg/mj/ll
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