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Daily Fishing and Outdoor Report

Tuesday, November 19, 2019: It didn’t take the boater boys long to get back on the bass ... sheepshead minnows overlooked

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Above: A couple Holgate enterprise shots I took shortly after the replenishment, as sand settled in.

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Below: I recently got into ink, pen and paper art, ordering essentials on-line. Not unexpectedly, I soon received an e-vertisement by a pen company that had magically gotten my name. The company obviously didn't get any other pertinent financial data if they thought this gift was right for me:
"Namiki Yukari Fountain Pen - Seven Gods Set of 7 (100th Anniversary Limited Edition) ... 

Namiki Yukari Fountain Pen - Seven Gods Set of 7 (100th Anniversary Limited Edition)

Namiki Yukari Fountain Pen - Seven Gods Set of 7 (100th Anniversary Limited Edition)$33,600.00

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Tuesday, November 19, 2019: It didn’t take the boater boys long to get back on the bass, post-blow. While the first captains zipping out in still-rough seas were thankful to find those striped fish still around, the size has sorta fallen off the table. Barely keeper fish were the norm. I had just got done writing this for my SandPaper column: “Pre-blow, boat bassing was bountiful, occasionally epic. When on the biomass, anglers had their ways with cow stripers to over 50 pounds. Forty-pounders were common. That big-bass bite has a little more time to go but will quickly changeover to schoolie fish in arm-tiring numbers. Among those schoolies will be a slew of eater bass -- exactly 28 inches is spot on for table fare.”

Hearing a wide array of water temps, with 50-ish being the average. I'll take some infrared thermometer readings tomorrow. 

I’m still convinced there will be some keeper stripers in the surf. We should have hard offshore winds for the next few days. This bodes well for my plugging and jigging efforts. It's also excellent windage for folks casting chunks. If you want to keep a plugging rod going, I'm still hyping Ava jigs and designer teasers, i.e. saltwater flies used as teasers.

Below via  avidangler.com

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Surf City Bait and Tackle
Another Derby Weigh In !!!!!

Duncan Turner with his 9.56 lb striper caught in SC on a SP Minnow

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Looks like another gloomy weekend forming up ahead. Here’s hoping sky-things will improve as we get closer. Then, it’s homing in on the long Thanksgiving weekend, a prime fishing time – and often the last coastal hurrah for many seasonal anglers.

SHEEPSHEADS SHUNNED: Kicking myself over the partial mistake I made regarding last week’s showing of bulbous-bellied schoolie bass feeding on what I assumed were striped killies/killifish, known as hardhead minnows. While there were a goodly number of oft-present hardheads – I’ve occasionally seen them under ice – the big forage fish I somehow failed to notice – due to my multitasking photography, fishing and clamming – were one of my favorite little guys: Sheepshead minnows.

For something like three years in succession, I kept a flock of sheepshead minnies in one of my two 55-gallon saltwater aquariums. Talk about little brutes. Not only would they eat anything, including unwanted algae growth, but they could survive any, let’s say, mismanagement of the tanks on my part.

While they are generally dark, even mildly iridescent, when first netted, once tanked they take on a far lighter, markedly lined look. In fact, they become aquarium material, looks-wise.

Before: 
After (a couple weeks): 

My sheepshead killifish also seemed to be highly perceptive. They would see me coming and all but bounce off the glass in anticipation of feeding. However, should a visitor walk up to the tank, they would frantically commence to hiding. That’s seem sorta smart on their part.

I’ll probably rile some animal lovers, but those hardheads got so food trained that I’d place food on the palm of my hand and barely hold it in the water. Dang if they wouldn’t slide onto my hand to eat -- and kept doing so even when I lifted my hand totally out of the water. I could see them chomping away, before finally slipping back into the wetness. I wrote an aquarium piece about that.

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I'll have to wait for my next blog in here to offer a segment I did for my weekly column on the long/much-needed dredging of the intracoastal waterway, from Cape May up to here. It's a 450-day federal project meant to make the famed waterway not only safer for boating but also navigable for Coast Guard rescue vessels. I'll make that SP column available on Facebook tomorrow -- or check thesandpaper.net. Folks south of LE Inlet will be particularly pleased with this deepening effort. I'm hoping it will address the shoaling problems off Holgate bayside.  

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Menhaden Fishing Quota Bill and Seabass Bill Released in Committee 

The following bills have been released in the Senate Environment and Energy Committee today, November 18th:

S3796 (Andrzejczak) and A5432 (Milam/Land): Requires DEP Commissioner to establish individual transferable quota system for menhaden purse seine fishery.

“Menhaden are an important species and the food supply and stability of our fisheries, but this bill would lead to overfishing of this critical fish. Our concern is that the bill will privatize the regulation and mandate by setting up this quote system. By locking in quotas for different fishing interests, we believe it will lead to overfishing. What is an even bigger problem is the trading system of quotas,” said Jeff Tittel.

“Menhaden are a critical link to the food web and are known as forage species. This means they function as a food source for larger species like blue fish and striped bass. Marine mammals and birds, including ospreys and bald eagles also rely on menhaden as a food source. The bill will accelerate depletion of menhaden. This legislation will essentially be a destructive domino effect throughout the marine food chain. It will not only impact these important species, but impact New Jersey’s commercial and recreational fisheries,” said Jeff Tittel.

S2675 (Andrzejczak/Van Drew):
 Permits commercial fishing vessels to possess more than daily trip limit of black sea bass and summer flounder, under certain conditions.

“Overfishing hurts populations, ecologies, and fishing industries in the long-term. Pollution and overfishing threaten black sea bass numbers. This bill directly threatens the sustainable fisheries practices that have helped our fish populations recover over the past decades. By giving in to the commercial fishing industry, they’ll be killing the goose that lays the golden egg. If we regulate and protect these fisheries, we’ll keep them sustainable for years to come. If we overfish them now, it will hurt us in the future,” said Jeff Tittel.

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An Arkansas company makes caskets that are shaped like fishing boats GloryBoats.com

Image result for gloryboats

We all know a guy who loves fishing more than they love life itself.

Well, what if I told you that you can send them off in a fishing boat once they are gone from the earthly plane?

That's the line of thinking that led Little Rock resident Joel Schmidt to start his company Glory Boats.

While sitting at his father's bed side in his final moments, Schmidt thought of the love his father had for being out on the water.

"If you hadn't told me what you wanted, I might have just buried you in your fishing boat," he joked.

Now, as he approaches one year since starting the company last August, Schmidt offers as a $2,800 model in three colors: woodland camouflage, marsh grass and pink camo, for the more extravagant of your loved ones.

Of course, Schmidt says, he got the idea for the pink camo casket from his mother, who he says loved the outdoors just as much as his pop.

But, thus far, Schmidt has seen that younger folks are more open to his product.

"Older generations are reluctant to break with tradition," he tells CBS News.

For those who have the time to think about their fate, maybe they'll come around to the idea. I hear a fishing trip is a great way to get some thinking done.

You can read more about Glory Boats on CBS.com or by visiting their website.

Get the latest from It's a Southern Thing by subscribing to our newsletter, where you'll find the latest videos, stories and merchandise.

NOAA Fisheries - New England - Mid Atlantic Bulletin

November 16, 2019

Watch Out for Turtles on NJ Beaches!

The recent cold snap has caused a sudden uptick in the number of cold-stunned sea turtles washing up on beaches in northern, NJ - particularly Sandy Hook and Long Beach Island. We are asking all individuals walking these beaches, and beaches throughout the northeast, to report stranded turtles immediately to our stranding hotline at 866-755-6622. Responders from our Sea Turtle Stranding and Salvage Network are standing by to help!

Please keep pets away from these turtles since they are in a severely distressed state. If possible, please move them above the high tide line and cover lightly with seaweed and stand by the animal until a trained responder arrives. We greatly appreciate your assistance in helping us save these endangered animals.

Cold-stunned sea turtle receiving a pre-flight check-up

Questions?

Media: Contact Allison Ferreira, Regional Office, (978) 609-1604

Below: Mark Temme is in Surf City, New Jersey.
Found 2 dead Green Sea Turtles washed up on bay beach at end of street. Thermal shock from cold water is likely culprit. Beautiful creatures.
No photo description available.

Pollock Parts Plug Body Holes, Clean Lead From Soil

Source: Fish Radio with Laine Welch

By Laine Welch
November 14, 2019

This is Fish Radio. I’m Laine Welch – Pollock parts plug body holes, clean soil and more. That’s up after this –

Sustainability is written into the Alaska Constitution and is a core principle for fishery management. Learn more at www.AFDF.org

IMS is offering special discounts on Refrigerated Seawater Systems through the end of the year.  Integrated Marine Systems.  Simple, reliable, built to last.  Visit imspacific.com

Fish Radio likes to spotlight fish parts that go well beyond dinner plates and can add up to more value than fillets.

Pollock, for example, Alaska’s largest fishery produces millions of pounds of fish sticks, surimi and roe – but other pollock parts are being used to seal holes in lung and blood vessels. 

Researchers at Japan’s National Institute for Materials Science (NIMS) have discovered that gelatin from pollock skins makes a sealant that is 12 times stronger than conventional uses.

A big plus is the fish gelatin remains liquid at room temperature and can be sprayed directly on an open wound. It has the potential to be used on any organ.  

Pollock skins also are an exciting new source for nanofibers that are similar to tissue in human organs and skin.   Bor-Sen Chiou is lead researcher at the US Dept. of Agriculture lab in Albany, Calif.

Hopefully, if you have a damaged organ you can grow these cells outside the body and be reintroduced into the wound and help improve the ability of the organs  to heal itself.

Chiou says studies show that fish gelatins improve cell growth far better than traditional animal gels.  

Along with pharmaceuticals, gelatin from pollock skins also has huge potential in the food industry. Food technologist Cindy Bower --

“They have substances that can be used in beverages as a thickener, as a clarifier for juices, plus you can roll it out into great films. When you test it against bovine and pig skin films, there is decreased water vapor permeability. These fish films are a better barrier to water. So there is some application for using them to coat foods – to keep moisture in or out. Plus, they’re fish so they satisfy kosher and Halal (Muslim) dietary restrictions.  That opens markets for millions of people worldwide.”

From skin to bones -- ground up pollock bones are being roto tilled into the soil in neighborhoods in Oakland, California to neutralize toxic lead. Nearly every urban US area has a lead problem, far more than can ever be cleaned up.

Now, instead of digging up and disposing of tons of contaminated soil, the calcium phosphate in tons of Alaska pollock bone meal is turning the lead into a harmless mineral.

The alchemy has been known for nearly 20 years and used most recently at mining sites and military bases.

Fish Radio is also brought to you by Ocean Beauty Seafoods - who salutes and says thanks to the men and women fishing across Alaska for their hard work and dedication. (www.oceanbeauty.com) In Kodiak, I’m Laine Welch.

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PENTAGON MAY HAVE RELEASED WEAPONIZED TICKS THAT HELPED SPREAD OF LYME DISEASE: INVESTIGATION ORDERED

Last week, the U.S. House of Representatives quietly passed a bill requiring the Inspector General of the Department of Defense (DoD) to conduct a review into whether the Pentagon experimented with ticks and other blood-sucking insects for use as biological weapons between 1950 and 1975.

If the Inspector General finds that such experiments occurred, then, according to the bill, they must provide the House and Senate Armed Services committees with a report on the scope of the research and "whether any ticks or insects used in such experiments were released outside of any laboratory by accident or experiment design," potentially leading to the spread of diseases such as Lyme.

The amendment was put forward by Rep. Chris Smith, a Republican from New Jersey, who was "inspired" by several books and articles claiming that the U.S. government had conducted research at facilities such as Fort Detrick, Maryland, and Plum Island, New York, for this purpose.

However, some Lyme disease experts are warning that Smith's claims should be viewed with plenty of caution. They include Phillip Baker, Executive Director of the American Lyme Disease Foundation (ALDF), who says Smith has been "terribly misinformed" with "false and misleading information."

One of the books that Smith refers to—called Bitten: The Secret History of Lyme Disease and Biological Weapons—was published earlier this year, authored by Stanford University science writer and former Lyme suffer Kris Newby. It features interviews with late Swiss-born scientist Willy Burgdorfer—the man credited with discovering the bacterial pathogen that causes Lyme disease—who once worked for the DoD as a bioweapons specialist.

"Those interviews combined with access to Dr. Burgdorfer's lab files suggest that he and other bioweapons specialists stuffed ticks with pathogens to cause severe disability, disease—even death—to potential enemies," Smith said during the debate on the House floor.

"With Lyme disease and other tick-borne diseases exploding in the United States—with an estimated 300,000 to 437,000 new cases diagnosed each year and 10-20 percent of all patients suffering from chronic Lyme disease—Americans have a right to know whether any of this is true," he said. "And have these experiments caused Lyme disease and other tick-borne diseases to mutate and to spread?" Smith asked.

According to Smith, the investigation into the claims should attempt to address several questions:

"What were the parameters of the program? Who ordered it? Was there ever any accidental release anywhere or at any time of any diseased ticks? Were any ticks released by design? Did the program contribute to the disease burden? Can any of this information help current-day researchers find a way to mitigate these diseases?"

Despite the passing of the recent bill by the House, the American Lyme Disease Foundation's (ALDF) Phillip Baker says Smith's claims are unfounded.

"I think that Rep. Chris Smith is terribly misinformed by the Lyme disease activists and by the false and misleading information," Baker told Newsweek. "He would be well advised to check the facts by consulting the experts on Lyme disease at the National Institutes of Health or the Centers for Disease Control and Prevention [CDC] for accurate and reliable information before proposing such legislation."

In a piece for the ALDF website, Baker noted that some people claim Lyme disease was introduced into the northeastern region of the U.S. after a strain of Borrelia burgdorferi—the bacterium that causes Lyme disease—escaped from the Plum Island biological warfare facility.

"However, there is ample evidence to indicate that both Ixodes ticks and B. burgdorferi were present in the U.S. well before the Plum Island facility was ever established," he wrote, adding that the center says it has never researched Lyme disease.

The symptoms of what is now known as Lyme disease were potentially first described in Scotland in 1764. Recent research has indicated that the Lyme disease bacterium was present in America in pre-Columbian times, many thousands of years before Europeans arrived on the continent.

Furthermore, Baker says the rationale for believing that Lyme disease was used as an agent of biowarfare is "flawed."

"Note that about 95 percent of cases of Lyme disease reported to the CDC occur in 12 states," he told Newsweek. "Based on what we know concerning the pathology of Lyme disease—and we know a lot—does anyone seriously think that people living in those 12 states are any more vulnerable to an enemy attack because of the high incidence of Lyme disease than those living in the remaining areas of the U.S.? That would be 'quite a stretch' to say the least."

"The main reason for considering a given pathogen for possible use as an agent of biowarfare is its ability to create terror and or havoc by causing serious incapacitating illness and/or death within a short time interval after its release," he said. "The bacterium that causes Lyme disease is not such an agent. If one were to prioritize a list of agents to be considered for use as biowarfare agents, the organisms that cause smallpox, plague, Ebola and anthrax would be at the top of the list. Only a fool would ever consider adding Borrelia burgdorferi, the bacterium that causes Lyme disease, to such a list. If it ever was given any consideration, and I have no knowledge that it ever was, it would not have been for more than a nanosecond!"

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Striped bass decline spurs new look at mycobacteria

Chronic disease infects most of the striped bass in the Chesapeake

  • By Karl Blankenship on November 05, 2019

When Wolfgang Vogelbein peered at striped bass sores through a microscope 22 years ago, he knew he was looking at something very different than what was grabbing headlines at the time.

An apparently healthy striped bass, left, and a suspiciously unhealthy one will have their spleens removed and tested for mycobacteria. (Dave Harp)

Pfiesteria piscicida — the so-called “cell from hell” — was being blamed for fish kills in Maryland and making people sick.

But what Vogelbein saw through his lens wasn’t the result of a harmful algae toxin. It was a nasty bacterial infection, creating ugly sores on the outside of fish and lesions on the inside.

The infections were caused by mycobacteria, a type of bacteria that are widespread in the environment, but not typically associated with problems in wild fish. Suddenly, though, it was turning up in large numbers of the Chesapeake Bay’s most prized finfish.

“I thought I would be spending the rest of my career working on myco,” recalled Vogelbein, a fish pathologist at the Virginia Institute of Marine Science.

It didn’t turn out that way. Mycobacteria never snagged the attention — nor large-scale research funding — as did Pfiesteria. Nor was it associated with high-profile fish kills or considered a human health threat.

Decades later, Pfiesteria has largely vanished from discussion, and some scientists now question whether it was responsible for fish kills at all.

But the mycobacteria problem never went away — and has only gotten worse. The majority of the Bay’s striped bass are infected and, by the time they are 5 years old, nearly all carry the disease. An unknown number are thought to die. “We think it is substantial,” Vogelbein said.

Now, with the striped bass population in trouble, the Bay’s mycobacteria problem may get another look. Striped bass numbers have been declining along the East Coast for a decade and a half, and a recent stock assessment for the Atlantic States Marine Fisheries Commission concluded that the population was being overfished.

The commission, comprised of East Coast fishery managers, at the end of October acted to reduce harvests 18% in the Bay and along the coast beginning next year in response.

But the assessment also raised questions about whether mycobacteria infections may be playing a bigger role in the decline than currently thought, citing studies that suggest even higher rates of mortality among striped bass from the Bay than assumed in the assessment. The study called for a better understanding of the impact the disease might be having in the Bay and coastwide, and flagged it as one of the highest research priorities.

If the disease is having a greater impact than previously thought, it could also mean any new fishing regulations would be less effective than hoped.

“There is likely an impact somewhere,” said Mark Matsche, a fish health scientist with the Maryland Department of Natural Resources. “My question is, what is the severity of the impact to the population?”

A mysterious disease

Mycobacteriosis — and what it means for the Bay’s most valuable recreational species — has perplexed scientists and fishery managers since it was first observed in 1997. It is a chronic wasting disease which, in aquaculture, usually results in death, but severe infections typically are not seen in wild fish populations.

Diseases affecting finfish are usually short-lived events, which sometimes result in dramatic fish kills and then disappear. In contrast, the mycobacteria infections in the Bay show no sign of relenting and are likely to take years to kill fish.

An enlarged spleen is a sign of a mycobacteria infection in striped bass. By the time they are 5 years old, 80-90% of the Chesapeake Bay’s striped bass carry the disease. (Dave Harp)

“We are not used to seeing this persistent, long-term epizootic which doesn’t seem to go anywhere,” Matsche said. “It is very, very different.”

Further, the two types of mycobacteria causing problems in the Bay — Mycobacterium shottsii and M. psuedoshottsii — were previously unknown. They were only discovered when a researcher at VIMS accidentally left slides with tissue samples from striped bass in an incubator, and colonies of the bacteria began to grow.

No one knows why they seemed to have suddenly appeared and become a problem. In early years after the discovery, only 10–20% of striped bass in the Bay seemed to carry the infection. Today, the majority are infected, and surveys in Maryland and Virginia show that 80–90% of striped bass carry the disease by the time they are 5 years old.

Also unclear is why striped bass are so susceptible. Although the same two mycobacteria species sometimes turn up in other fish, they don’t seem to have the same impact, even in closely related species like white perch.

Nor does the disease seem to be a problem outside the Bay. While there is some anecdotal evidence that infections are seen in other areas, they do not seem as widespread or severe as in the Bay, and it’s unclear whether they are even the same mycobacteria species.

There is also some evidence that the disease may progress more slowly in adult fish after they leave the Chesapeake. That makes scientists suspect there may be some type of stress in the Bay that makes the condition worse — but it’s unclear what that might be.

Efforts to answer such questions have lagged in recent years. Aside from some support after the initial discovery, research funding largely dried up. The striped bass population, after bottoming out in the 1980s, was thriving by the time mycobacteria infections were discovered.

“Things were so good with striped bass — management was in a great place, anglers were happy and the pressure wasn’t there to deal with a crisis mode,” said Robert Latour, a VIMS fisheries scientist. “It was, ‘How do we enjoy this recovered fishery?’ And there were many other fires for fisheries managers to put out.”

Slow killer with uncertain impacts

The biggest unanswered question is the extent to which the infections are actually killing fish and impacting the striped bass population.

The disease progresses slowly, with the condition of the fish deteriorating over time. Scientists believe many of the infected fish die, but how many and how quickly are difficult to determine.

“We are not seeing thousands of fish washing up on the shoreline,” said David Gauthier of Old Dominion University. “They are probably dropping out of the population a few at a time and getting eaten by crabs, so it is not highly visible. So trying to measure how much mortality there is on a population basis is really difficult.”

An intensive study years ago on the Rappahannock River, in which striped bass were tagged, recaptured and examined over a period of years, concluded the mortality rate of infected fish was double that of uninfected fish.

Still, that’s not the full story. It’s unclear whether the disease shaves a few months, or many years, off the lifespan of an infected striped bass. If it survives long enough to reproduce, the impact of the disease on the overall population might be minimal.

On the other hand, a number of sublethal impacts could also be important. For instance, studies show that infected females tend to mature earlier and are smaller than uninfected fish. Because smaller fish produce fewer eggs than larger ones, the reproductive capacity of the population might be reduced.

A rockfish awaits a necropsy. Its spleen will tell whether it has been infected with mycobacteria. (Dave Harp)

Trying to figure out what that means for the overall striped bass population is further complicated because most do not spend their entire lives in the Chesapeake. They are spawned in the Bay, and the young live there for several years. Eventually, most move to the ocean until returning to spawn, though some males never leave the Bay at all.

And while the Chesapeake is thought to be the largest component of the overall coastal population — and the focal point of the disease — it’s unknown just how much of the coastal stock they constitute. It’s also unknown how many males stay in the Bay and how many leave.

“We feel like it is a problem within the Bay for the time that the resident population is here, but sort of casting that into the broader, full coastwide population is a little more murky because of these missing pieces of information,” said VIMS’ Latour.

Modeling the population

The model used in the Atlantic States Marine Fisheries Commission assessment to estimate the size of the striped bass stock lumps the entire population together. If striped bass from the Chesapeake Bay are dying at a faster rate than fish elsewhere, it has no way to precisely account for the difference.

As a result, increased mortality caused by mycobacteria is not directly factored into the stock assessment. Estimates of “natural mortality” — fish that die because of all non-fishing activities — have been adjusted over time for the entire coast, but it’s not known whether they fully capture the impact of the disease.

Complicating the problem is that those estimates are based partly on tagging studies. Each year, biologists along the coast place tags on striped bass, asking that they be returned when those fish are caught, often years later. That helps biologists estimate the ultimate fate of fish.

But return rates for tagged fish have declined since the striped bass population crisis ended decades ago. It’s not totally clear how much of that decline is caused by the loss of fish to disease and how much is from public apathy.

“We don’t know how many of the fish that disappear are dying naturally, and how much is because they are caught and people are seeing them again, but just aren’t telling us,” said Katie Drew, the stock assessment team leader with the ASFMC.

She said the assessment’s overall estimates of total striped bass mortality are probably correct because it matches what is observed in the overall population trend. But it’s possible that the population model underestimates natural mortality and overestimates fishing mortality.

In either case, she said, the remedy is the same — reduce fishing pressure — because managers have no control over the disease. But if disease is responsible for a larger portion of overall mortality than assumed, and fishing causes a smaller portion, efforts to reduce the catch may have less of an impact than hoped.

“You will see some benefit in reducing fishing mortality for sure,” Drew said. “But if natural mortality is a much bigger component of total mortality than we think, it won’t be as big of an effect.”

The commission might get better estimates in the future. It wants to move away from a stock assessment model that lumps the entire striped bass population together and toward one that separates the population by regions —allowing them to better estimate disease-related impacts on fish spawned in the Bay.

Models to do that have yet to pass scientific peer review. But scientists are optimistic they will be ready for the next striped bass assessment in several years.

Trying to answer questions

In the wake of the recent stock assessment, scientists are working to fine-tune what they think they can say about the disease’s impact on striped bass.

“I think people are really eager to get to the bottom of this and to try to better understand what might be causing this particular epizootic in the Bay,” said Genevieve Nesslage a fisheries scientist with the University of Maryland Center for Environmental Science.

Nesslage is working with a graduate student to use disease data that the state collects each year, along with environmental and other information, to build a computer model that examines potential population-level impacts of disease- related mortality in the Bay. They also want to try to identify environmental triggers that may worsen its impact on infected fish.

Likewise, Vogelbein, Gauthier and Latour are working to analyze many hundreds of samples from striped bass collected over the last decade that have been preserved but never examined because of a lack of funding. The hope is that a larger, richer set of data will help paint a clearer picture of what’s happening — at least in the Chesapeake.

Because most “deaths” are seen in computer models rather than the real world, that improved understanding will help modelers better predict disease impacts, and mortality, on the population and gain confidence in their results.

“Models are only as good as the data that go into them,” Vogelbein noted.

Scientists generally believe that some stress factors are playing a significant role in making the disease impact worse.

Variables such as increased temperatures, large oxygen-starved dead zones — even increased particulates in the water — have been suggested as factors that speed the decline of infected fish. Some think changes in striped bass diet, related to changes in menhaden abundance, might have reduced their health and made them less resistant to disease.

The renewed focus might shed light on those issues.

While the disease progresses over time, that progression isn’t always steady. Matsche said that some recaptured fish show relatively little change after several years, but some are considerably worse after a single season. “There are a lot of variables at play here that we don’t fully understand,” he said.

If those factors could be understood — and alleviated — it might open another door for management to help the fish.

Does a dead zone equal dead fish?

One prime suspect is the Bay’s poor water quality. During the hot summer, striped bass seek refuge in deeper, cooler water. But if the Bay’s oxygen-starved dead zone makes those areas off limits, it pushes the fish into warmer water that is more stressful — and may make them more vulnerable to disease progression.

A laboratory study several years ago by scientists at VIMS showed that when infected fish were exposed to both low dissolved oxygen and higher temperatures, they appeared fatigued and were likely less able to elude predators or pursue prey fish to eat.

Jim Gartland, an assistant research scientist at VIMS, has observed this in the wild as well. Gartland, who helps conduct a fish survey along the entire length of the Bay each year, said striped bass in midsummer heat appear especially stressed near areas of low oxygen water.

“When you are in the dead zone area, you will see them just easing along the surface sometimes,” Gartland said. “And striped bass usually don’t do that.”

If such a correlation between environmental conditions and disease exists, it could offer both hope — and peril — for striped bass.

While there may be little that can be done about the disease itself, such work could suggest that some actions — such as accelerating nutrient reduction efforts aimed at eliminating the dead zone — might reduce disease impact on striped bass.

On the other hand, Bay water temperatures are already warming, and if that trend continues, it could stress striped bass even more and make oxygen conditions worse.

“This level of a significant pathogen in a population is kind of ominous,” Gauthier said. “It is possible they are holding their own against it right now, but what is going to happen? They are already sort of at the edge of their thermal limit down here. What is going to happen in the future if the environment keeps changing?”

After two decades of wondering, scientists hope a resurgence in interest will help shed light on those questions.

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