Bobby Graves was trying to win a fishing tournament. A $1,000 prize was on the line for catching the weekend's biggest spotted seatrout in a zone encompassing the lower reaches of the Wicomico and Nanticoke rivers in Maryland.
So, when he reeled in a species more typically found in subtropical waters, his initial reaction was disappointment. "Just get it in the net and get it off," Graves recalled thinking, "so we can get back to what we're trying to catch."
Bobby Graves shows off the record-size Florida pompano he caught on Sept. 17, 2023, in waters off Bloodsworth Island in Dorchester County, MD. (Courtesy of Bobby Graves)
That accidental Sept. 17 catch turned out to be a winner of another sort. At 6.44 pounds, the Florida pompano set a size record for the species in Maryland waters, according to the state Department of Natural Resources biologists who confirmed the catch.
Graves, a native of Salisbury, MD, said he has been regularly fishing in the Bay for six decades but only began noticing pompano in the last few years. DNR didn't officially recognize the species as a record candidate until 2019.
"They're still an oddity," he said. But "I think the Bay waters are warming slightly, and it's just an influx of different species."
For the most part, the Chesapeake Bay and its tidal rivers remain an anglers' paradise. But what they're angling for is beginning to shift as water temperatures warm, according to climate and fishery experts. Many recreational fishermen say they're already seeing a difference.
A spate of recent research across the globe suggests the warming climate will likely drive many fish species northward to flee the heat.
One of the most comprehensive modeling efforts to date, led by scientists at Rutgers University-New Brunswick, predicts that fish currently found from Maine to North Carolina will shift northeast along the continental shelf by an average of about 400 miles by 2100 under a high-emissions scenario.
Such changes could be economically devastating to fisheries in the Chesapeake Bay, particularly species that live in cooler waters, scientists say. For example, striped bass, a popular species known as rockfish in the Bay region, typically venture only as far south as North Carolina's Outer Banks. By century's end, according to the Rutgers study, they could find themselves pushed about 220 miles northward.
"Maybe eventually, it gets too warm for them" in the Bay, said Noah Bressman, a fisheries expert at Salisbury University. "But all those species where maybe it's just one degree too cold for them now [in the Bay region], give it 100 years. They may move farther north, and now they can survive here."
Among southeast fish, which include those that are currently rare sights in the Chesapeake region, the typical species was expected to migrate about 150 miles northward, the Rutgers study predicts.
The transformation is already happening.
Since the 1980s, the average summer surface-water temperature in the Bay has increased by about 2 degrees, while the average winter water temperature has risen by about 0.6 degrees, according to research by the Virginia Institute of Marine Science.
The warming has helped give rise to a group of fish known as "tropical visitors." Gamefish already making their presence known in the Bay, researchers and fishermen say, include red drum, Atlantic cutlassfish, sheepshead and mangrove snapper.
Their numbers can vary from year to year, depending on the weather, said Erik Zlokovitz, a recreational fisheries coord-inator with the Maryland DNR. The time of year is also a factor.
"Generally, August, September and maybe early October is the time we see these south-eastern species. It's when both water temperature and salinity are the highest. It's better conditions for these fish," Zlokovitz said.
He added, "It's definitely one of the positives and side benefits, I guess, of climate change."
In 2020, the state agency that tracks record-size fish catches in Virginia officially added a new target: Atlantic tripletail, a species more common to waters off Georgia, Florida and the Gulf states. They are not new to Virginia but appear to be getting caught more often as bycatch as anglers increasingly pursue cobia, according to the Virginia Marine Resources Commission. The current record catch is a 16-pound, 12-ounce specimen caught in July 2021 near the York Spit Light.
Scientists aren't sure what to make of the new arrivals. It's hard to study organisms that makes such rare appearances. Many warmth-adapted fish only pop up in official records a few times over a period of several years. Such a sample size is too small to determine if the local population is increasing, said Dave Secor, fisheries biologist with the University of Maryland Center for Environmental Science.
"It may be that people are getting pretty good at fishing for them or maybe there's something going on, like there's more artificial structure out there," he said.
But one study may offer some clues. Cobia, which can grow up to 4 feet long and weigh 50 pounds, tend to overwinter off the Atlantic Coast from Florida to North Carolina. But during summers, they spawn in coastal estuaries, including the Chesapeake, which is near the northern extent of their range. They now account for 225,000 recreational trips a year in Virginia alone.
A recent Virginia Institute of Marine Science study has found that cobia are arriving in the Bay nearly a week earlier in the spring and staying nearly two weeks longer in the fall, likely because of warming temperatures. The researchers forecast that the trend would lead cobia to remain in the Bay an additional 65 days by 2100 compared with the present.
But much of the cobia's fate depends on how climate change unfolds in the region, the VIMS researchers pointed out. If the fish arrive earlier and, therefore, spawn earlier, critical temperature cues and a suitable environment may not be in place yet. The population could decline as a result. This mismatch in timing is widely expected to lead to upheaval for many species as the grip of climate change tightens.
This article was originally published on BayJournal.com and is republished with permission.
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