Syracuse.com - Cayuga Inlet Fishway provides wild rainbow trout eggs for fish stocked in five Finger Lakes

[HuntingNY-News]

DEC workers this week reached their goal of collecting 174,000 eggs from spawning fish.

DEC worker Will Smith holds up a female rainbow trout after he squeezed out its eggs. David Figura | [email protected]  

DEC worker Ian Blackburn was splashing around in his waders down inside the Cayuga Inlet Fishway Wednesday morning, netting trapped wild female and male rainbow trout.

“I’m going to give you a few more males,” Blackburn said. “The more the merrier.”

Standing on grates above and taking the netted fish from Blackburn were Denise Richardson, another DEC worker and volunteer Keith Hunter, of Newfield.

The threesome gathered nearly two dozen females and males in water-filled tubs on the fishway’s grated deck. The fish, from nearby Cayuga Lake, run up the Inlet this time of year to spawn and get trapped.

Soon after , Ken Osika, manager at the DEC’s fish hatchery in Bath, arrived along with two seasonal hatchery workers to extract the eggs and sperm from the fish on tables. The process went quickly. It involved firmly squeezing the belly of each fish beginning with the front and working back toward the anus. The extracted eggs and sperm squirted out of the fish into big bowls on the tables.

“You add a little water to activate the sperm and the eggs are fertilized almost immediately,” Osika said. He said the goal this year was to get 175,000 eggs from the spawning rainbows, fertilize them and to take them back to the hatchery.

Before the eggs are loaded up, they’re soaked in iodine to sterilize them.

In addition, the eggs are soaked in a vitamin B-1 solution (thiamine). The process increases their survival rate and prevents “early mortality syndrome,” which is prevalent in Cayuga Lake and elsewhere as a result of the adults feeding on alewives. The baitfish are widespread in the lake and contain a chemical that causes the syndrome.

“What we used to do many years ago is take the fish back to the hatchery and put them in our raceway. And then with our warmer water, they’d ripen (faster) and we’d do our egg take over there,” he said.

Osika explained precautions, such as soaking the eggs in iodine, have to be taken to prevent spreading anything from Cayuga Lake to the hatchery. “There’s so many invasive species and diseases, things like VHS (a deadly fish disease) that you have to watch out for,” he said.

Back at the hatchery, he explained, the eggs will be incubated and hatched and raised. They rainbows will then be stocked this fall and the following year in tributaries of Cayuga, Skaneateles, Owasco, Seneca and Keuka lakes.

The egg collection process this years started March 28 and this was their third trip to the fishway this spring, Osika said. As a result of Wednesday’s take, the hatchery reached its goal.

The Cayuga Inlet Fishway was built as part of the construction of a flood control weir for the city of Ithaca spanning the Inlet back in the late 1960s, explained Hunter, who managed the facility for nearly a decade in the 1970s. Original plans did not include a way for the spawning fish to pass around the weir.

The weir, which spans the Cayuga Inlet, was originally built as a flood control measure. David Figura | [email protected]  

Hunter said the Cornell’s Dwight Webster, a fishery biologist, came up with the plans for a Denil fishway – a horseshoe-shaped, concrete setup, complete with baffles and chambers, that diverts and traps spawning fish making their way up the Inlet. The fishway opened in 1969 and was later taken over by DEC.

For decades, it’s been a relatively easy and convenient location to get rainbow eggs. The Cayuga Lake strain of wild trout has been dependable for stocking purposes.

Apart for those eggs that are fertilized with sperm from wild Cayuga Lake rainbows, the DEC for several decades has had a rainbow trout hybrid program using eggs taken from Cayuga Lake’s wild rainbows.

“We produce 15,000 yearling rainbows that are stocked annually into Skaneateles Lake each spring,” Osika said. “To do that, we take the eggs from about eight females and fertilize them with sperm obtained from the males at the DEC’s Randolph Fish Hatchery.”

Osika noted the hybrids are adaptable to hatchery life and food, and aren’t as skittish. They’re essentially easier to raise and grow faster and get longer before getting stocked, compared to the wild rainbows.

“The bigger the fish, the better the survival. They also have some wild attributes as well, so they adapt better to the lake,” he said.

The biggest fish netted this year at the fishway measured 29 ½ inches, said Blackburn. It was female that weighed about 9 ½ pounds. Osika, who has been managing the Bath hatchery for moe than 20 years, said he’s seen some fish taken over the years that have weighed 12 pounds or more.

Other spawning fish also making their way into the fishway this time of year, including suckers and lamprey eels.

“The suckers, we take them out and allow them to continue on their way,” Blackburn said. The lampreys are taken out, counted, measured and end up at the local landfill.

FINGER LAKE RAINBOW STOCKING

Fall: The DEC hatchery in Bath provides 20,000 rainbow fingerlings (2-3 inches) for stocking in Salmon Creek, a tributary of Cayuga Lake; 20,000 fingerlings for the Owasco Lake Inlet and 5,000 for Cold Brook, a tributary of Keuka Lake.

Spring: The hatchery provides 5,000 yearling rainbows (averaging 6 inches) for direct stocking in Owasco Lake; 15,000 hybrid rainbows for direct stocking in Skaneateles Lake, plus 5,000 regular fish; 10,000 for Catharine Creek, a tributary of Seneca Lake, and 12,500 each for the Cayuga Lake Inlet and Enfield Creek (a tributary of the Inlet), plus an additional 10,000 for Salmon Creek.

View the full article on The Syracuse Outdoors Blog