Coonamessett River Herring To Be Tagged 3/12/15

Coonamessett River Herring To Be Tagged
The Enterprise

Posted: Thursday, March 12, 2015 12:17 pm
ENTERPRISE STAFF

Using radio collars on bears or bands on a bird's legs is a method to track their seasonal migration and movements. The same methods can be used on fish. The Coonamessett River Trust (CRT), working with Falmouth's Office of Marine and Environment Services, will tag incoming alewives and bluebacks, known collectively as river herring, on the Coonamessett River this spring.
Volunteers will catch and tag up to 400 river herring with passive integrated transponder (PIT) tags near the catch basin area. When the released fish swims though the wire loop of an antenna, the PIT tag is energized and sends a signal with the embedded tag number to a data logger which records the fish tag number, the date and time. In this way each individual fish's movement can be tracked.
Not only will this information help answer several questions about the herring and the river system, it is also a great way for the public to become involved by "adopting a fish."
The CRT has been manually counting migrating herring on the Coonamessett for more than 10 years. Volunteers count for an hour every evening between 7 and 10 PM from mid-April through May. They count at night because Coonamessett River herring do not like to move upstream during daylight, perhaps due to the lack of trees covering the river that leaves them vulnerable to overhead osprey and gulls. The estimate of the 2014 migration was 44,000 fish.
Although it is not known how many fish pass under the berm between Lower and Middle bogs, tagging the fish will help the trust understand and answer important questions about where they travel within the system. There are three potential ponds where alewives can spawn. It is assumed the majority of the alewives head all the way up to Coonamessett Pond, several miles upstream. But that is not known for certain. Some of them may stop at Pond 14, an old flooded cranberry bog just south of Sandwich Road. Then there are others that might make a right turn into the Flax Pond system. It is unclear which one is the main spawning area.
This information will assist herring warden/deputy director R. Charles Martinsen in ongoing efforts to identify and make passage improvements.
Humans have modified the river for centuries with mill construction and cranberry cultivation along the banks and its river valley. Numerous culverts and barriers now exist as a result of those activities. Some of these structures restrict fish movement and degrade habitat by modifying flow, changing water temperatures and/or altering streambed characteristics.
It is unknown what percentage of the river herring population are alewives and which are bluebacks. Bluebacks spawn in the river, unlike their pond spawning cousins. Perhaps one type prefers one area of the system to another.
It is also unknown how long the adults stay after they spawn. Do they go downstream right after spawning or do they stay awhile before returning to the sea?
River herring live five to six years and always return to their natal river. In 2016, the tagging program will show how many of the tagged fish return to the river.
There will be three counting stations. One will be near where the herring enter Lower Bog. This will reveal when the tagged fish move through the Lower Bog barrier and move upstream. A second will be at the entrance to Flax Pond, and the third will be at the entrance to Coonamessett Pond. These two stations will allow an estimation of the percentage of herring that spawn in each pond.
These counting stations were made possible by Linda Deegan, who uses counting stations in Alaska to monitor the migration of arctic grayling. Dr. Deegan is a senior scientist at the Ecosystems Center of the Marine Biological Laboratory.
The public can participate in this effort by "adopting" a fish for $10 each or three for $25. Donors can name their fish, and at the end of the season, the trust will be able to tell each person when their fish was tagged, where it went, and when it left and headed back to the ocean.
Those interested in adopting one or more herring may contact Charles Cooper at This email address is being protected from spambots. You need JavaScript enabled to view it. or Lou Turner at This email address is being protected from spambots. You need JavaScript enabled to view it. .
Bluebacks and alewives are anadromous fish in that they spawn in fresh water and spend the rest of the year in salt water. The CRT is hopeful that the collected data will ultimately help identify and prioritize fish river passage improvements, reduce mortality, and increase reproductive success to help return these fish to their historic populations.