WINTERPORT, Maine — A team of fisheries biologists and volunteers tromped along the banks of Cove Brook at the end of January, burdened by hoses and backpacks, funnels and cones and coolers.
More than one observer pointed out that the backpack-wearing scientists looked like they were auditioning for a role in a “Ghostbusters” sequel.
Come to find out, there was nothing unusual about their gear at all.
Nope. Nothing odd at all … if, that is, you think the idea of “planting” Atlantic salmon eggs in a streambed in the middle of winter makes perfect sense.
And if you do, you’ve got to meet Paul Christman.
For the past several years, Christman has been been planting eggs in the Sandy River drainage of western Maine, with staggering results. Last week, Christman joined biologists from the Bangor Department of Marine Resources office to kick off a multiyear egg-planting project on one of this region’s most sensitive pieces of water — Cove Brook.
Cove Brook, which flows into the Penobscot River in Winterport, was among the first Maine waters where Atlantic salmon were listed by the federal government as “endangered” more than a decade ago. And though salmon can swim freely into the stream upon their return from the ocean, biologists are hoping to jump-start a salmon run by seeded the streambed with eggs provided by Craig Brook National Fish Hatchery in Orland.
“This is the first time that we’ve [planted] eggs in the Penobscot drainage,” said biologist Norm Dube, who works out of the Bangor office.
Dube pointed out that stocking live fish is routine in the drainage, and the practice has been used for years.
“We stock upwards of 550,000 smolts, somewhere between 200,000 and 300,000 parr, and in the neighborhood of 1 million fry, each year,” Dube said. “But it’s all above Veazie. Very little is done down on this end. It’s free-swim [to the ocean, with no dams] and they’ve always had fish here.”
Dube said introducing Atlantic salmon eggs, rather than the small, hatched fry, or larger smolts, could turn out to be a key tool in restoration efforts.
“It’s the least hatchery influence that you can get,” Dube said. “They’re in the wild. They emerge [from eggs] in the wild. They’re getting all the pressures of surviving in the wild. Technically, it’s a fish that is better prepared to survive in the stream as well as in the ocean.”
All of which helps explain why the egg-planting team was carrying all that equipment … like a backpack-mounted water pump that has revolutionized the egg-planting routine.
“Digging a hole in a stream in the middle of winter is a challenge beyond comprehension,” Christman said, explaining that when he started trying to plant eggs on the Sandy River, early efforts were hampered by that reality.
Also, he said, the fact that biologists were trying to plant eggs that were in incubators — those incubators eventually were removed from the streambed — made efforts even more difficult.
Enter the backpack water pump.
“We pull water right out of the stream and a jet of water will loosen the substrate and we’ll be able to basically stick a pipe right down into the substrate,” Christman said. “It drills incredibly fast.”
As the hole is dug, a pipe sinks into that streambed, and a funnel is attached. Eggs — about 600 per hole — are poured into the funnels. And when the funnels are retracted and the pipe removed, sediment sifts down around the eggs, leaving them covered and safe.
“We’re the mother salmon,” Christman said. “Which puts a lot of pressure on us. If we don’t do the right things, they don’t do well.”
So far, it appears that biologists are doing all the right things. Christman said biologists are planting eggs and utilizing water pumps in western U.S. rivers, but to his knowledge, none are using the cone-and-pipe planting technique that has worked so well.
Biologists measure success by assessing “emergence,” or the percentage of salmon eggs that actually hatch as salmon fry. They do that by laying a trap net over the top of some of their homemade redds in the spring, having already counted the eggs that were planted on each of those sites. Any eggs that hatch are caught, and biologists such as Pete Ruksznis, who is running the Cove Brook operation out of the Bangor DMR office, will count them.
“[Before the new planting techniques] we were getting about a half a percent up to 10 or 12 percent [emergence],” Dube said. “With this process we’re seeing up to 48 percent. It’s simulating a natural redd. It’s a lot better.”
Better, and faster.
Before the water pump method was used, Christman’s crews could spend 14 hours trying to bury incubators holding 12,000 salmon eggs. In a single day on Cove Brook the crew planted 56,000 eggs.
And last year alone, Christman planted 860,000 eggs in the Sandy River system.
Christman said heading to Cove Brook allows the DMR to diversify its restoration efforts on an ecologically important stream.
“It’s outside of the systems that I’m working, where we’re burying eggs now, so it gives us another place to try it that’s outside,” Christman said. “It’s in the Penobscot drainage, which is good, because we’re doing a lot of other restoration here. It gives us a direct comparison [to the Sandy River project]. Also, the high quality of Cove Brook [is a factor].”
Dube said that for years, even without stocking the lower Penobscot, Cove Brook had a nice run of 30 to 50 adult salmon returning each year. Now, Cove Brook’s run is nonexistent. And Christman said if the DMR’s efforts on Cove Brook prove worthwhile, it may pave the way for similar efforts in tributaries of the Penobscot.
“If it works in a stream like this, the possibility is there that we can expand it,” he said. “And we’re in such a large watershed, it’s a great place to expand.”