By Karl Blankenship, Chesapeake Bay Journal
If you saw this creature in a stream, you’d run for cover.
The footlong image on Josh Tryninewski’s computer screen had an eerie, transparent body with two large bulging eyes at one end. A strange white sac was hanging underneath.
You could find one in a stream, but not easily.
It’s not a mutant — but an American shad, just hours after hatching. The one on Tryninewski’s screen was actually a tiny speck just a few millimeters long, floating in a petri dish and greatly magnified through a microscope.
“This is day zero — just welcomed into the world today, in the comfy confines of a nice blue tank,” said Tryninewski, a fisheries biologist with Pennsylvania’s Fish and Boat Commission.
The tiny fish was one of roughly 4 million shad expected to be reared this spring in the state’s Van Dyke Hatchery. But the shad “fry” projected onto Tryninewski’s screen could also be among the last.
The Pennsylvania Fish and Boat Commission last year announced plans to eliminate funding for the Van Dyke Hatchery after the 2018 spawning season. That would end a 42-year operation that has pumped nearly 281 million shad fry into the Susquehanna River, the Chesapeake Bay’s largest tributary. Nearly 30 million more have been reared for the Delaware River.
The commission in April reaffirmed its decision to close the hatchery, which costs about $200,000 a year to operate, as well as two other hatcheries as part of an overall $2 million budget cut effective July 1.
Although the commission is an independent agency, the state legislature has to approve increased fees for fishing licenses, the commission’s largest source of revenue, which have not gone up since 2005.
“Unless legislators act, we must cut expenses to remain financially solvent,” said John Arway, the commission’s executive director. (Click Here for more.)
That seems unlikely. Many lawmakers oppose any fee hike, and some view the commission’s threat to close hatcheries as heavy-handed and have instead introduced legislation that would limit the term of its executive director, effectively throwing Arway out of his position.
If the issue is not resolved, the reddish plywood building located a stone’s throw from the Juniata River, a Susquehanna tributary, could close its doors for good after it finishes stocking bug-eyed shad fry in June.
“It’s concerning,” said Tryninewski, who has been overseeing the hatchery since 2014, “because in three to five years you are going to have 40 to 50 percent fewer shad [in the Susquehanna] than what’s there now.”
An Upstream Battle
Getting shad back in the Susquehanna has been a challenge for more than 150 years.
Shad are anadromous, meaning they are born in freshwater rivers but spend most of their lives in the ocean along the Atlantic Coast before returning to their native river to spawn.
Spring migration runs in the Susquehanna — which holds the most spawning habitat of any East Coast river — began declining in the mid-1800s, in part because spawning runs were hindered by small dams built to divert water into adjacent canals.
The Pennsylvania legislature created the fish agency in 1866 to restore shad runs to the river. But the situation worsened in the early 1900s when four large hydroelectric dams were built on its lower stretch, totally blocking fish migration.
In 1976, with shad having nearly disappeared in the river below the dams, the utilities that owned the facilities paid to build and operate the Van Dyke Hatchery to help restore its population.
Ultimately, the goal was to put the hatchery out of business by helping the shad to get upstream on their own to spawn.
In the 1990s, the utilities spent tens of millions of dollars building fish passages that would physically lift fish over three of the dams, while allowing them to swim over a ladder at the fourth.
When the last passage was completed in 2000 — theoretically opening the entire river to fish migration — utility funding for the hatchery ended, along with an operation to capture shad below the dams and truck them upstream.
But the passages were never as effective as anticipated. In recent years, only a few thousand shad have made it past the first three dams, where they begin to find suitable spawning habitat. Since 2010, the number getting past all four has ranged from 8 to 224.
So the commission has continued operating the Van Dyke hatchery to help maintain a population in hopes that the passage issues would eventually be resolved.
“The number that are getting to the spawning grounds has been dropping the last 10 or 15 years,” said Sheila Eyler, who coordinates fish restoration efforts on the river for the U.S. Fish and Wildlife Service. “So the role of the hatchery has actually gotten more important to sustain that run and keep it going until we can address the fish passage problems that we have.”
Battling The Odds
The bug-eyed shad under Tryninewski’s microscope had arrived via truck a little more than a week before, among a batch of eggs harvested from the Potomac River.
The eggs came in plastic bags and were carried into a biosecure room where the bags were floated in tanks of water until they reached about 60 degrees. After that, they were placed in egg incubation jars — four foot-high clear plastic tubes which can hold several hundred thousand eggs that are constantly stirred by a gentle upwelling of water.
Like much of its equipment, the incubation tubes were custom-made for the hatchery, and they’ve aged. Many are held together with epoxy, hot glue and duct tape. “We treat all of these as if they were antiques, because they kind of are,” Tryninewski said.
After eight days, the fry start to emerge from the eggs, and the tubes are moved into large blue tanks filled with slightly warmer water — 64 degrees — overnight.
The next day, the tubes are taken outside and the eggs stirred with a turkey feather to speed hatching — “the eggs and the fry don’t stick to the feather,” Tryninewski explained. The hatching is greatly accelerated if it’s also sunny outside.
The fry are then released into the large, blue tanks, about 5 feet across, each of which can hold a half-million larval fish. The first couple of days they live off the white yolk sac from the egg that remains attached.
After that, they begin gorging on a blend of brine shrimp and dried commercial fish food, which automatically sprinkles into the tank every 15 minutes.
The larvae are tiny, but the ensuing feeding frenzy is hard to miss.
“You see them racing through and dimpling on the surface?” Tryninewski asked. “They go after it pretty good.”
Starting at three days, the tanks are treated with tetracycline, a chemical that accumulates in the only bone that exists in the tiny fish — the ear bone, or otolith. That allows biologists to identify hatchery-reared fish when they are recovered in the wild.
After about 20 days, when they’ve reached a length of roughly three-quarter of an inch, the tiny fish are removed from their blue tanks. Just as they arrived, they leave in plastic bags and are carried to their destination in coolers.
Those reared from eggs from the Susquehanna and Potomac rivers, about three quarters of the roughly 4 million shad expected to be reared this year, will be released in various Susquehanna tributaries. The other quarter, reared from Delaware River eggs, will be released in that basin.
Biologists float the bags in river water, allowing the temperature to adjust before the bags are opened, and the fry — still translucent and bug-eyed — swim out.
They’ll be easy pickings for predators, so biologists typically release half a million or more at a time. “That way they are overwhelming any predators that may be there,” Tryninewski said.
By fall, the juvenile fish will have left the Susquehanna by passing through the turbines of large hydroelectric dams in the lower part of the river. They’ll spend four or five years swimming along the Atlantic Coast.
“They don’t stop swimming until they are dead,” Tryninewski said. “They don’t take a rest, they just keep going.”
If they survive the gantlet of predators in the ocean, about one out of every 425 that are released into a Susquehanna tributary will return as an adult to spawn.
3-Pronged Effort
Or try to. For many, the return journey will be futile because only a fraction of the migrating fish make it through the passages to spawning grounds upstream.
Upgrades to the passages are planned as part of relicensing agreements with dam owners, but completion would be years away.
In the meantime, biologists hope that some migrating shad would be captured from the river, trucked around the dams and released to spawn as part of a trap-and-transport program Exelon has agreed to implement among the terms of a new operating license.
Exelon owns the 94-foot-high Conowingo Dam in Maryland which, just 10 miles upstream from the Bay, is the first dam encountered by migrating fish.
But it’s unclear whether that will be ready to start next year as hoped, because Exelon and the state of Maryland still have issues to resolve before a new license can be finalized.
“If a license were issued in late 2018 or early 2019, there may be a potential for limited trap and transport in 2019, but I really wouldn’t expect much to happen until 2020,” Eyler said.
If not, 2019 could be the first year since 1976 without juvenile shad produced above the dams.
In any case, biologists had viewed upstream shad restoration on the Susquehanna as a three-pronged effort: Some fish would be carried over the dams as passages are upgraded, others trucked around them, and the hatchery would continue to stock fry. That way, rebuilding the shad population would not depend on just one technique or technology.
If Van Dyke is closed, that prong would be removed from the equation.
Shad Stocking Struggles
It would also accelerate the dramatic decline in shad stocking around the Chesapeake. After Van Dyke opened, more than half a dozen hatcheries in the region, operated by states, federal agencies and Native American tribes, began churning out millions of fry as part of an all-out effort to rebuild the population in the Bay watershed — an effort that also included new fish passages, dam removals and harvest moratoriums.
Shad historically were a revered species in the region migrating far up the region’s rivers — on the Susquehanna, they supported fisheries as far north as New York — and their restoration has long been a goal of the state-federal Bay Program partnership.
As recently as the 1950s, they were the most valuable fishery in the Chesapeake, but overfishing, pollution, loss of habitat and the construction of dams that closed off historic spawning grounds have all contributed to the population collapse, scientists say.
While there have been some bright spots — the Potomac stock has been steadily increasing — their spawning populations are at near historic lows in most East Coast rivers.
In the [Chesapeake] Bay region, hatchery production peaked in 2000, when 36 million shad were stocked in various Bay tributaries.
Over the next decade, though, stocking began to decline.
Because of concerns about declines in other rivers, Van Dyke was no longer able to import large numbers of eggs from the Hudson, which had been a major source and pushed its production to well over 10 million in some years.
The Potomac, the Bay tributary with the healthiest population, became the egg source for Van Dyke and most other hatchery production throughout the region.
But gradually, other hatcheries closed because of budget cuts or shifted their focus to other species. This year, in a cost-cutting move, the Virginia Department of Game and Inland Fisheries stopped funding the hatchery production of shad for the James River, ending a 25-year effort.
If Van Dyke closes, the only major American shad stocking activity next year will be by Maryland on the Choptank and Patapsco rivers, where the state each year tries to stock 2.75 million and 200,000 respectively, and by Delaware on the Nanticoke River, where a record 1.3 million shad were stocked last year.
Across the Bay region, shad production will have fallen nearly 90 percent from its peak.
By themselves, hatcheries in the region have failed to restore large shad populations in once-major spawning areas like the James and Susquehanna rivers.
But biologists say the blame likely lies with pressures from outside the region — such as the bycatch of shad in commercial ocean fisheries — which has driven shad populations along most of the Atlantic Coast to near-record lows.
On the other hand, many note, if it weren’t for hatchery production, shad numbers on the Susquehanna would be far lower than they are today.
“The hatchery fish they are releasing are still contributing pretty significantly to the adults that are returning to the dam,” said Steve Minkkinen, who heads the USFWS Maryland fisheries office.
Numbers are not precise, but the Maryland Department of Natural Resources estimates the Upper Bay shad run is roughly twice as large as it was three decades ago.
And DNR biologists say they are seeing evidence that their hatchery efforts are paying off as adult shad are starting to return in the Choptank and Patapsco.
“We’re cautiously optimistic,” said Chuck Stence, of the DNR’s anadromous fish program. But, he added, “restoration doesn’t occur over several years. It could be decades.”
Whether time will run out on Van Dyke remains to be seen.
If the hatchery closes, restarting it may be difficult. The microscope Tryninewski used to show off just-hatched shad fry is the most high-tech feature in the plywood building. The operating manual hasn’t been updated since 1997, and Tryninewski said “there’s a lot of Rube Goldburg things around here. It is definitively function over form.”
Most of the operating knowledge is handed down from biologists who have worked at the hatchery over time.
“For someone coming in cold trying to get this facility up and running,” Tryninewski said, gesturing to the pipes crisscrossing the hatchery to the various tubes and tanks, “…you look at this and it just looks like spaghetti.”
(Photo: Josh Tryninewski examines shad “fry” produced at Pennsylvania’s Van Dyke Hatchery using a microscope that projects them onto a computer screen. (Dave Harp).)
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(Reprinted from the Chesapeake Bay Journal.)
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