October 31, 2013 at 9:48 am
Once a nationally renowned brown trout fishery, the tailwaters around Shawmut Hydroelectric Project, referred to as Shawmut, have hastily
[caption id="attachment_218" align="alignright" width="240"]
One of the tagged brown trout post surgery. The antenna from the implanted tag is visible near the tail of the fish.[/caption]
and inexplicably slowed in trophy brown trout production. Following the initial scratching of heads and speculations, fisheries biologists are delving deeper to uncover the cause of the decline.
The projected two year, multi-faceted study began in May 2013 with angler creel surveys (discussed previously in Spring Fishing Census and Aerial Angling Surveys) and monitoring of a multitude of variables effecting trout growth, and mortality including competitor/predator fish species, water temperatures, dissolved oxygen trends (the amount of oxygen in the water available for fish respiration and survival), and water velocity. Biologists are also studying brown trout, survivability, and growth as it pertains to and differs between strains stocked. Maine hatcheries currently stock three different brown trout strains throughout the state: Connecticut or Seeforellen strain, Massachusetts or Sandwich strain, and New Gloucester strain. These two new strains, Seeforellen and Sandwich, are being stocked on an experimental and limited basis. The New Gloucester strain is Maine’s long standing production brown trout. Due to genetic differences between these strains, often one strain exhibits improved hatchery and post stocking growth, and/or survivability than the others in specific habitat types. As Shawmut is a stocked fishery, and conditions in the river may have changed strain differences may play an important role in growth and survivorship of fish stocked.
A new investigation is underway and may offer greater insight on how to enhance and restore this once popular fishery and perhaps provide improved understanding regarding the root cause of the initial Shawmut brown trout fishery decline. Biologists have surgically implanted radio transmitters in 12 New Gloucester strain and 12 Sandwich strain brown trout. These fish were monitored in the hatcheries in a controlled setting for a few weeks to be sure the fish recovered and adapted to the implants appropriately; they were stocked at Shawmut on October 29, 2013. Information regarding the movements and mortality of these tagged fish will be recorded and observed and will prove invaluable to discovering the cause of the brown trout decline at Shawmut.
Through the dedication, innovation, and diligence of fisheries biologists, we hope to restore Shawmut to the world-class trophy brown trout fishery it once was.
Other noteworthy studies where MDIFW is stocking tagged fish for study are the Saco River below Skelton Dam and the Kennebec River in Solon. Biologists are conducting strain studies in the Kennebec and looking at seasonal habitat use and movement as well as sources of mortality on the Saco. While it is legal for anglers to harvest the tagged fish, we do request you release them. If you do catch one and want to keep it, please remove the tag while cleaning the fish and return it to the contact information on the tag. Thank you!
[embed]http://youtu.be/PDGNB0xVhtM?list=UU54uMeXmwftxUHJdBTqYTEA[/embed]
One of the tagged brown trout post surgery. The antenna from the implanted tag is visible near the tail of the fish.[/caption]
and inexplicably slowed in trophy brown trout production. Following the initial scratching of heads and speculations, fisheries biologists are delving deeper to uncover the cause of the decline.
The projected two year, multi-faceted study began in May 2013 with angler creel surveys (discussed previously in Spring Fishing Census and Aerial Angling Surveys) and monitoring of a multitude of variables effecting trout growth, and mortality including competitor/predator fish species, water temperatures, dissolved oxygen trends (the amount of oxygen in the water available for fish respiration and survival), and water velocity. Biologists are also studying brown trout, survivability, and growth as it pertains to and differs between strains stocked. Maine hatcheries currently stock three different brown trout strains throughout the state: Connecticut or Seeforellen strain, Massachusetts or Sandwich strain, and New Gloucester strain. These two new strains, Seeforellen and Sandwich, are being stocked on an experimental and limited basis. The New Gloucester strain is Maine’s long standing production brown trout. Due to genetic differences between these strains, often one strain exhibits improved hatchery and post stocking growth, and/or survivability than the others in specific habitat types. As Shawmut is a stocked fishery, and conditions in the river may have changed strain differences may play an important role in growth and survivorship of fish stocked.
A new investigation is underway and may offer greater insight on how to enhance and restore this once popular fishery and perhaps provide improved understanding regarding the root cause of the initial Shawmut brown trout fishery decline. Biologists have surgically implanted radio transmitters in 12 New Gloucester strain and 12 Sandwich strain brown trout. These fish were monitored in the hatcheries in a controlled setting for a few weeks to be sure the fish recovered and adapted to the implants appropriately; they were stocked at Shawmut on October 29, 2013. Information regarding the movements and mortality of these tagged fish will be recorded and observed and will prove invaluable to discovering the cause of the brown trout decline at Shawmut.
Through the dedication, innovation, and diligence of fisheries biologists, we hope to restore Shawmut to the world-class trophy brown trout fishery it once was.
Other noteworthy studies where MDIFW is stocking tagged fish for study are the Saco River below Skelton Dam and the Kennebec River in Solon. Biologists are conducting strain studies in the Kennebec and looking at seasonal habitat use and movement as well as sources of mortality on the Saco. While it is legal for anglers to harvest the tagged fish, we do request you release them. If you do catch one and want to keep it, please remove the tag while cleaning the fish and return it to the contact information on the tag. Thank you!
[embed]http://youtu.be/PDGNB0xVhtM?list=UU54uMeXmwftxUHJdBTqYTEA[/embed]Categories