By Kendra Raymond
Anglers in the Sebago Lakes region benefit from the skilled fishery management that takes place behind the scenes. Fisheries biologists work year-round collecting data and managing fish populations to maintain the resource in a way that anglers want. Hatchery staff coordinate spawning operations and raise the fish in a controlled and safe environment. This includes whatever population is needed to maintain the species and provide good size quality.
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| Landlocked salmon swim near the Mill Street Dam in Raymond. A salmon sticking program there has the fish enter a collection facility where they are sorted by hatchery staff by sex and age class. When the females are ripe, the staff strip eggs and milt from the salmon, fertilize the eggs, disinfect them and bring them to the Casco Fish hatchery for rearing. PHOTO BY BRUCE SMALL |
“Some of those fish will ascend the fish ladder and enter the collection facility where fish are then sorted by hatchery staff by sex and age class,” said Regional Biologist James Pellerin. “When the females are ripe hatchery staff strip eggs and milt from the salmon, fertilize the eggs, disinfect them, and then bring them back to the Casco Fish Hatchery for hatching and rearing.”
This is all part of a fisheries management program that aids reproduction and ensures enough fish.
“These fish support salmon stocking programs for southern and central Maine, which lack sufficient natural reproduction to sustain salmon fisheries,” said Pellerin. “In addition, MDIFW fisheries staff use the opportunity to collect data on the Sebago salmon to assess age and growth providing us long-term monitoring that goes back to the late 1960s.”
He says that there may be another egg retrieval in upcoming weeks to catch some of the unripe females.
Raymond resident Bruce Small is fascinated with the event and recently posted about the salmon egg collection on social media.
“I went on an annual visit to see the landlocked salmon run in Raymond on the Jordan River,” Small said. “They come up from Sebago to spawn. I have witnessed this almost every year since I first saw them in 1973. It has always fascinated me. The number of fish varies from year to year, but this was a banner year. I saw the most I have ever seen.”
Steve Tremblay, Casco Fish Hatchery Supervisor Supervisor, said that “egg takes” have taken place on the past two Wednesdays and anyone is welcome to observe.
The fish culturists who took part in the operation this year were from the Casco Fish Hatchery including supervisor Steve Tremblay, assistant supervisor Kenyon Twitchell and fish culturist Hayden Pelletier. Assisting from Dry Mills Fish Hatchery were supervisor John Dumais and from Palermo Fish hatchery was fish culturist James Beaudry.
Tremblay explained the process.
“The egg retrieval is the spawning operation. We spawn each individual fish, male to female from a different age class determined from a fin clip on the fish that was done before the fish was stocked in Sebago Lake,” he said. “We then take an aliquot of each fish we spawn and use the aliquots from all fish spawned and use that for our production fish that we hatch, rear and stock out of our facility in Casco,” he said. “This procedure gives us the best genetic variation we can have for our fish. This procedure we do every year supplies the state of Maine with all the Sebago strain of Landlocked salmon used to stock our waters that require the Sebago strain of Landlocked salmon.”
He described the timeline.
“After the eggs are fertilized at the fish trap in Raymond, we leave the eggs in buckets for a minimum of 1 hour to harden the water which allows us to safely transport the eggs to the hatchery in Casco. Once they arrive at the hatchery, they are bathed in an iodophor solution for 15 minutes to disinfect the eggs before they are allowed in the hatchery. This process prevents any type of potential diseases or viruses etc. from outside sources infecting our facility. Once disinfected they are rinsed and counted. This process involves taking a sample and measuring the size of the eggs in a 6-inch trough which we then can convert using a chart to figure out how many eggs are in an ounce.
“We then can measure how many ounces we have and calculate how many eggs we have on hand. This procedure is called the Von Bayer method of counting fish eggs. The eggs are then put on trays with 24 ounces of eggs on each tray,” Tremblay said. “The next morning, we must go through all the eggs and pick out all the dead eggs that are present. We can determine a dead egg by turning white. After this process is done, we must leave the eggs to incubate through the winter. The eggs after the 24-hour period are fragile and cannot be touched. We then can only treat them every other day with a formalin solution to keep the fungus that attaches to the eggs that die after we do our initial pickoff. The length of time it takes for the egg to incubate is determined by the water temperature. The warmer the water the faster the eggs develop. Our facility is lake fed, and our water temperature is cold throughout the winter, so our eggs incubate slowly. The eggs usually have a visible eye by January. At that point, the eggs are no longer fragile, and we do what we call shocking the egg. This is done by pouring the eggs in a bucket from about 2 feet into another bucket. This process will make the dead eggs that have not turned white turn white so we can determine the dead ones. We then must go through all the trays again and pick off all the dead eggs.”
They hatch out early to mid-March and the sac fry that emerge from the eggs start to swim up and feed in late April early May depending on water temperature, said Tremblay.
Bill Brennan is a member of the Panther Pond Association. He is proud of the group’s contributions to the Mill Street dam/Panther Run renovation.
“The dam was recently renovated this past year with significant involvement by Panther Pond Association and completed in time for the big day. I went over to the dam yesterday and the fish were jumping and ready,” he said.
Tremblay said that he also is pleased with the upgrades to the dam.
“The improvements to the dam have made managing water flow much safer and easier to maintain,” he said. “The dam improvements will also make managing water levels on Panther Pond and Crescent Lake much easier throughout the year and during heavy rain events.”
Brennan said that the PPA is an active group which has both a Facebook page and website.
“Over the last several years (PPA) was very involved with the state in renovating the dam,” he said. “Really rewarding to see so many things well planned and organized by the groups.”
Tremblay mirrored that sentiment.
“We are very pleased with the dam project and my mind is much more at ease not having to worry about the condition of the dam and potential catastrophic dam failure possibility,” he said. “The importance to this spawning operation and culturing fish in the state of Maine is critical to allowing fishing opportunities for the state. The states fish hatcheries supply a fishery to many places that would have very little or no opportunities for a wonderful fishing experience for sportsman. The fish hatcheries are also responsible for helping to maintain a fishery where it could not keep up with fishing pressure and other factors that exist,” he said.
Check out this underwater drone footage of the Sebago Lake landlocked salmon spawning run, provided by Maine DIFW: https://youtu.be/sa07-OUhj6Q?si=YPsTOOF3Fr0nIA4a
Learn more about the Panther Pond Association at: https://www.pantherpondassociation.org/ or search for Panther Pond Association on Facebook. <
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