When David Secor started his career at the Chesapeake Biological Laboratory almost three decades ago, one of his first projects concluded that the Atlantic sturgeon had all but disappeared from polluted Maryland waters.
The population of the massive fish — often 14 feet long — that once swam with dinosaurs plummeted in the 1900s amid rising demand for their eggs, better known as caviar. Overfishing devastated the species for the same reason caviar is such an expensive delicacy: Sturgeon roe is scarce because females don’t produce it until they’re about 10 years old. Even then, the fish don’t spawn every year.
So Secor and other biologists were shocked and then intrigued when, over the past decade, watermen and recreational fishermen started spotting what looked unmistakably like sturgeon flopping and splashing around the Nanticoke River on Maryland’s Eastern Shore. One even landed on the deck of a fisherman’s boat.
“I’m delighted to be wrong,” said Secor, whose research focuses on the resilience of exploited fish species. A sturgeon comeback could be one more sign that efforts to improve the health of the Chesapeake Bay are working.
Biologists in Maryland and Delaware have caught and tagged more than two dozen adult sturgeon in the Nanticoke River and its tributaries since 2014. One female was more than 7½ feet long and weighed 180 pounds.
This year, the scientists plan to conduct research that could prove sturgeon are actually being born here. They now suspect the ancient bottom feeders have been spawning in the Nanticoke right under their noses.
So it might not really be a comeback. Maybe they’ve always been there, and scientists were just looking for them in the wrong places and at the wrong time.
To help solve the mystery of the prehistoric fish, researchers are relying on modern-day spyware.
Historical records suggest tens if not hundreds of thousands of the primitive and distinctive fish lived in the Chesapeake in the late 1800s, Secor said. Adult sturgeon, which like salmon or shad spend most of the year in the ocean but swim up freshwater rivers to spawn, probably were hard to miss in the bay back then. They have sharklike tails and catfishlike snouts on bodies that can grow as long as 16 feet.
“You would have noticed them for sure,” said Secor, a professor at the University of Maryland Center for Environmental Science.
But then came a “black gold rush” for caviar, all but wiping out the species. Sturgeon catch along the Atlantic coast fell from as much as 7 million pounds a year to 20,000 pounds by 1905 — and just 400 pounds by 1989, according to the National Oceanic and Atmospheric Administration. In Maryland, a sturgeon catch of 700,000 pounds in 1890 plummeted to 22,000 pounds by the 1920s and even smaller numbers after that, until a coastwide moratorium on fishing for sturgeon began in 1998.
The Nanticoke was the last place spawning sturgeons were documented in Maryland waters, back in 1972. The river and its tributaries in Dorchester, Caroline and Wicomico counties run through marshes that even today have largely been preserved from development.
Since then, there have been at least two efforts to revive the Chesapeake sturgeon population. But neither appeared to be successful.
In 1995, scientists stocked the Nanticoke with 3,000 juveniles from a New York hatchery. But they don’t think the fish ever came back to Maryland after heading for the ocean. They might have been too old for the Nanticoke to have registered with them as a future spawning ground, said Chuck Stence, a state fisheries scientist.
The next year, the Maryland Department of Natural Resources began offering rewards — $25 for juveniles and up to 10 times that for a six-foot-long sturgeon — for any accidental catches commercial fishermen turned in. State scientists hoped to build a captive population they could release periodically. The program brought in 2,000 sturgeon, but biologists tested them and found they were all just passing through; their genes linked them to populations from Virginia, the Hudson River and elsewhere.
That bounty program was forced to end in 2012, when the federal government declared Chesapeake sturgeon an endangered species, making it illegal to remove the fish from the water.
So in 2013, a recreational fisherman found himself outside the law when a sturgeon literally jumped into his boat.
Bill Harris has been fishing on Marshyhope Creek, a Nanticoke tributary that meets the river in Dorchester County, for 20 years. But it wasn’t until about 2011 that he first thought he saw a sturgeon jump. He started documenting the sightings in his fishing log, including the time in September 2013 when one breached right onto the deck of his boat.
His friend Randy Roland snapped a photo, and Harris posted it to Facebook. That’s when he heard from concerned fish biologists.
“They’re endangered species. You’re not supposed to take them out of the water,” Harris, now 75, recalled. But he didn’t get in trouble.
Instead, the biologists asked him questions, and Harris told them what he had been seeing. It wasn’t what the scientists had expected.
Historically, Chesapeake sturgeon were caught in the spring and into early summer. In those records, “there was no mention of a fall run,” Secor said.
And the scientists just assumed that, like other large fish, the sturgeon spent most of their time in deeper waters.
But here they were, in relatively shallow creek waters as summer was turning to fall.
By 2014, the DNR’s Stence managed to catch some and test their genes. They weren’t related to the fish released in 1995, descended from Hudson River sturgeon. And they didn’t come from Virginia’s James River, where this fall scientists found baby sturgeon for the first time in a decade.
The Nanticoke sturgeon were full siblings to fish caught in the Pamunkey River, a tributary far upstream on Virginia’s York River — a population discovered in late summer 2013.
“We never expected that in a million years,” Stence said.
In the past four years, scientists in Maryland and Delaware have caught and tagged as many as 27 adult sturgeon on the Nanticoke and Marshyhope and in Broad Creek, a Delaware tributary. They’re caught in nets, wrestled into tanks on board a 25-foot boat and lulled to sleep using a light electrical current.
“They’re big, strong fish,” Stence said. “They beat you up a lot.”
Within five or 10 minutes, they are implanted with a radio transmitter and released back into the water.
Buoys scattered up and down the Chesapeake and the Atlantic coast track their movements. They usually arrive in the bay around June and leave in October. This time of year, Stence starts getting emails from researchers in the Carolinas and Georgia telling him that the sturgeon have passed by monitoring equipment there.
The next step is to find out for sure whether the sturgeon are successfully spawning on their treks up the Chesapeake, and whether their young are surviving. This year, the researchers hope to duplicate the recent James River discovery and use trawls to capture, document and release juvenile sturgeon in the Nanticoke system.
Delaware biologists recently have been finding “robust” populations of juvenile sturgeon in the Delaware Bay, said Ian Park, a fish biologist with that state’s Department of Natural Resources and Environmental Control. And they are helping look for the fish in portions of the Nanticoke that extend into the First State.
“If we could document another spawning pop in the Nanticoke River, that would be pretty good for the recovery of the species,” he said. “The ultimate goal would be to recover the species from the threat of extinction and to eventually manage harvest of the species again.”
It would also be a promising sign for the recovery of the Chesapeake because sturgeon are particularly sensitive to sediment pollution that can come from development and a lack of forest buffers around streams. Their eggs stick only to gravelly surfaces, which sediment tends to cover. Gravelly areas also provide shelter for young sturgeon.
It’s likely to take a few more years to understand just how robust the sturgeon population might be and to know more about the mystery behind their reappearance. Secor said the discovery is nonetheless dramatic.
Sturgeon “serve to represent something more than they are,” Secor said, “the health of the Chesapeake.”