Biologists in Maryland were surprised this spring when a waterman reported that a 7-foot, 170-pound Atlantic sturgeon turned up in his pound net off Tilghman Island.
No one had seen such a large fish in decades, despite a reward program that pays watermen $50 when live sturgeon are reported.
Biologists were excited when, after taking the fish to the lab, it turned out to be a female. And they became thrilled when it turned out the fish was getting ready to spawn.
“It’s pretty exciting,” said Brian Richardson, of the Maryland Department of Natural Resources’ Fisheries Service. “In 10 years of this reward program, we have not seen a single ‘ripe’ female.”
The last time an egg-filled sturgeon turned up in Maryland’s portion of the Chesapeake was 1972—Richard Nixon was president and gasoline was 40 cents a gallon.
“It’s exciting,” said Andrew Lazur, who oversees the hatchery at the Horn Point Laboratory of the University of Maryland’s Center for Environmental Science, where the fish was taken. “It’s something we’ve been wishing for—hoping for—for years.”
Although sturgeon can live 60 years in the wild and don’t return to native rivers to spawn until they’re about 15, biologists are skeptical the fish originated in Maryland waters. The state’s reward program has turned up roughly 1,700 fish in the past decade, but they were overwhelmingly juveniles with a smattering of near-adult males—all of which were likely wandering through from other areas. No reproducing adults or newly spawned “young of year” fish have turned up.
The James River in Virginia and the Delaware Bay are the nearest locations with known spawning populations.
“It is fairly likely, considering our past surveys, that this was ultimately going to end up someplace else,” Richardson said. “We don’t have any evidence that it was coming up to spawn in Maryland.”
Nonetheless, biologists hope to spawn the fish at the lab and do an experimental release of young sturgeon this summer.
“I think it’s very unlikely she would continue whatever migration she was on after going through that amount of handling,” said Steve Minkkinen, head of the U.S. Fish and Wildlife Service’s Maryland Fisheries Office. “Why not try to do some good with the eggs she was going to produce this year?”
Sturgeon—the largest fish native to the Chesapeake, growing to lengths of 12–14 feet—historically spawned in most large river systems in the Bay from the James to the Susquehanna. They were severely overfished in the late 1800s. With added stress from pollution and habitat loss, many populations never recovered.
Over time, sturgeon disappeared from all Bay tributaries except the James River, and possibly the York.
The fish are so scarce that a panel of scientists recently recommended that the species be listed as threatened under the federal Endangered Species Act. A final decision on that recommendation is expected later this year.
Interest in bringing back sturgeon is booming, though. Sturgeon are long-lived bottom feeders that require good water quality. Many biologists believe that the ability to restore healthy sturgeon populations in Bay tributaries would also signal healthy conditions. “Their survival is almost like a bioindicator of the river itself and environment quality,” Lazur said.
Virginia scientists are undertaking a multiyear study to better understand the size of the James River populations and the location of crucial habitats as part of a long-term program to restore the stock. (See “VA scientists searching for secrets of stealthy surgeon,” on page 17.)
Maryland biologists, who have no population to rebuild, have focused on the idea of a hatchery-based stocking program to restore sturgeon.
In 1996, they released into the Nanticoke River on Maryland’s Eastern Shore more than 3,000 1-year-old sturgeon raised in a U.S. Fish and Wildlife Service hatchery at Lamar, PA. Monitoring showed that those fish survived well, remaining in the vicinity for several years before moving into the ocean.
Since then, biologists have been raising sturgeon in Maryland hatcheries and developing spawning and production techniques that would be needed should a large-scale stocking program be launched.
Ironically, until the fish was caught off Tilghman Island by waterman C.R. Wilson, the big news for scientists was that one of the sturgeon held back from the Nanticoke release, now a 12-year-old female, was finally ready to spawn at Mirant Energy’s aquaculture facility at its Chalk Point plant on the Patuxent River. It will be the first Atlantic sturgeon to be spawned that was raised entirely in captivity.
“When it rains it pours,” Minkkinen said. “We’ve been waiting a dozen years to spawn one. Now we’ve got two.”
Biologists thought both fish would be ready to spawn in late May or early June. At that time, the fish will be injected with hormones to cause the female to begin releasing eggs. Once that starts, biologists will remove the eggs through an incision. The eggs would be fertilized with sperm from males caught in the Bay in recent years.
It’s unclear where the young would go—if anywhere. Any stocking would be regulated by the Atlantic States Marine Fisheries Commission, a panel of state and federal fisheries officials that is responsible for regulating migratory fish species along the East Coast.
Although a large female can produce 2 million eggs, ASMFC guidelines only allow 50,000 fish from a single female to be released as part of a research program, out of concern that the offspring of a single fish would dominate future populations in a river and lead to inbreeding.
Minkkinen said biologists will almost certainly propose stocking some fish in the Potomac—sturgeon are known to prefer big rivers, and the Potomac had a spawning female as recently as 1970. Last year, a cousin of the Atlantic sturgeon—the shortnose sturgeon—was observed making a spawning run in the Potomac.
But it’s possible fish could be released in several rivers so biologists could compare survival. Biologists want to decide soon so larvae can be raised in water from the river where they will be released.
Like most other anadromous fish, sturgeon “imprint” on the river where they were born and return to those areas to spawn. No one is sure when that imprinting takes place, and biologists want to hedge their bets.
“We want to make sure that these fish are imprinted, and since no one has done the research on when these things imprint, we are going to assume that they imprint very early in their life,” Minkkinen said.
Still, because it takes sturgeons more than a decade to mature, he and others working on the project will be waiting a long time to find out whether they got it right.
In the meantime, the experimental release would allow biologists to study techniques to monitor the fish and learn what habitats they use. The fish released in the Nanticoke in 1996 fared well, but were also a year old. Scientists want to know how younger fish would fare when confronted by predators and current habitat and water quality conditions.
“We don’t really know what the habitat is like for larval sturgeon or any young-of-year sturgeon,” Lazur said. “To do those test releases and see how they survive will give us a good indication of today’s water quality and whether they would be appropriate stocking locations in the future.”
Adopt a Sturgeon
Ongoing sturgeon work is mostly unfunded. The public can make a donation to support sturgeon restoration, and learn more about efforts, at the University of Maryland’s Adopt a Sturgeon website: www.adoptasturgeon.org.