Gulf of Maine Distinct Population Segment of Atlantic Salmon (Salmo salar)—Beau Zacharia

Beau Zacharia

Gulf of Maine (GOM) District Population Segment (DPS) of Atlantic Salmon

                                                                

                         

 Description and Ecology

https://www.fws.gov/northeast/greenlake/images/atlantic_salmon_960x350.jpg

Geographic and Population Changes

Historically, Atlantic Salmon were divided up into three distinct groups: Long Island Sound, Central New England, and the Gulf of Maine. Both the Long Island Sound and Central New England districts have since become completely extirpated, as the GOM DPS Atlantic salmon is the last native salmon to secure its native habitat (eight total streams). Since the GOM district has stood alone they have experienced an extreme decay of the returning adults to spawn and rear newborns, climate change has disrupted both juvenile and adult populations, and more invasive and nonnative species have been introduced, which has caused the GOM Atlantic salmon to widely expand its geographic range. Also, from the water temperatures steadily increasing and more species being introduced these salmon have been forced to expand their geographic ranges. The freshwater range for the GOM Atlantic salmon occurs in the watersheds from the Adroscoggin River northward along the main coast to the Dennys river. The GOM DPS Atlantic salmon are spread throughout the Northern Atlantic Ocean when at sea.

https://www.fws.gov/mainefieldoffice/images/atlantic%20salmon%20map.jpg

Listing Date and Type of Listing

•      listed on December 17, 2000 as Endangered
•      listed by IUCN Red List (Endangered)
•             second status review and listing expanded on June 19, 2009: stating these salmon are in critical habitat (Gulf of Maine DSP)

Primary Cause(s) of Listing
There are five primary causes of listing for the GOM DPS Atlantic Salmon. The first cause being the overall current or vulnerable destruction, curtail, or modification of the species habitat and range. The second cause is how these Atlantic salmon are being over exploited from commercial, recreational, scientific, and educational activities. The third cause, how Atlantic salmon are very vulnerable to many different types of bacterial, viral, and fungal disease, which decrease their hatchery populations. Also, predators are a main concern due to their range expanding, letting in new nonnative species (problem because the higher possibility of predators lends to the endangerment of the few adult salmon left returning to spawn more fish). The fourth cause, is the insufficiency of the existing regulatory mechanisms related to dams. Both hydroelectric and non-hydroelectric dams make the travel between the sea and fresh water nearly impossible for the Atlantic salmon due to each dam being very small, not having a fish passage, and many of the dams being inoperable. The fifth cause is the natural or manmade factors that bring harm to the species overall survival. An example is dams, which cause water quality degradation and barriers for migration.
https://www.nefsc.noaa.gov/sos/spsyn/af/salmon/images/fig41_5.gif

Main Threats to Continuance of Existence

1.    Dams

Dams would be identified as a main threat to the GOM DPS Atlantic Salmon due to how they severely obstruct their migration pathways, which significantly increases the direct/indirect killing of these Atlantic salmon. Also, dams deter historically native habitats from salmon, embody hydroelectric turbines that causes an excess of mortality to kelts and smolts, reduce the water overall water quality, and change the salmon community’s composition, leading to a delay in their migration patterns.

http://atlanticsalmonrestoration.org/resources/documents/atlantic-salmon-recovery-plan-2015/recovery-plan-pages/salmo_graph.png/@@images/4ec76d88-b2c6-429a-be12-0be1f3ff88fe.png

2.    Inadequate Regulatory Mechanisms related to Dams

Another threat would be the inadequate regulatory mechanisms related to dams because it is a major concern for GOM DPS Atlantic salmon in regard to providing passage ways to assist their survival.  Most dams that cover the range of the GOM segment are not a helping factor to generating electricity, are too small to begin with, have absolutely no fish passageway, and most of the existing dams are dysfunctional or no longer in use.  The Federal Energy Regulatory Commission has not been helpful at either producing the necessary fish passageways or adopting any regulations for implementing new dams.

3.    Marine survival

There are four general sources that contribute to the decline of the GOM DPS Atlantic Salmon over the last 25 years (both direct and indirect):

Ø  Predation

Creates a disproportion between the increasing population of both native and nonnative species and the low number of adult Atlantic salmon that return to spawn and rear new babies. While the numbers of predators are rapidly increasing due to the change of range for this species, these more known predators are also significantly affecting the juvenile population of salmon as well.         

Ø  Starvation

Due to the ocean temperature increase in the North Atlantic, the abundance of plankton which GOM DPS Atlantic salmon feed on are disappearing. From this lack of food at sea the adult GOM salmon that return to spawn and rear are becoming extremely starved, sometimes to the point of death, when migrating upstream.

Ø  Disease and parasites

Disease and parasite outbreaks occur in both natural and hatchery settings. The GOM DPS Atlantic salmon is already at high risk for disease due to how easily susceptible they are too multiple viral, bacterial, and fungal diseases. Parasites can also affect this species too, mostly occurring during hatcheries. There are federally managed conservation hatcheries, which help control the spread of disease and parasites through strict protocol. These hatcheries strive to manage and prevent pathogens spreading between their facilities and river systems.

https://upload.wikimedia.org/wikipedia/commons/2/2c/Shrimp_hatchery.jpg

Ø  Changing ocean conditions (abiotic factors)

Due to the increase of overall temperature around the world (Climate Change), it has caused the oceans which Atlantic salmon roam to increase in temperature. This increase in ocean temperature causes the water to become acidified. Since the ocean water is acidified (decrease in pH), it decreases the quality of one of their primary prey, Capelin. Also from the changing ocean conditions it raises ocean sea levels, which has decreased the growth and wellness of plankton. Due to the decay of plankton, it has caused salmon who travel back upstream to rear and spawn to become starved and unhealthy.

Description of Recovery Plan

•          November 2005

The Discovery Plan for the GOM DPS Atlantic salmon:

1.        Habitat connectivity: make the transition between freshwater and ocean habitats
2.          Preserve the genetic diversity of Atlantic salmon population for future success.
3.         Conservation hatchery: increase the number of adult spawners, this should be done through more conservation hatchery programs.
4.         Fresh water conservation: the main focus is to increase adult spawners through fresh water production of smolts. Aim to make dams more functional and not as harmful for water conditions.
5.        Marine and estuary: to maximize Atlantic salmon survival by providing a better understanding of their ecosystem. This would help others identify the spatial and temporal restrictions to salmon marine productivity, and enlighten and support management activities that increase survival.
6.        Federal/Tribal Coordination: Discuss and approach all involved Tribes on a government-to-government basis.
7.       Outreach, Education, and Engagement: Reach out and team up with partners, while engaging with parties willing to work towards the recovery efforts for the GOM DPS.

Main hope in recovery plan: To bring listing of GOM DPS Atlantic salmon from Endangered to Threatened

What can YOU do?

The public contributes a great amount in the Atlantic salmon recovery by following the implemented practices that can help protect these Atlantic salmon. One crucial thing that is important to do is maintain and protect the areas that provide shade and nutrients which are essential in supporting Atlantic Salmon. The second way you could help this species would be to maintain native vegetation near waterways, which can help decrease erosion of topsoil to conserve healthy forests. Many Atlantic Salmon use the space between rocks to lay their eggs and protect their juvenile fish from any predators. Lastly, people in the community can participate in programs that focus on conserving resources that are important for Atlantic Salmon’s shelter as well as making sure that water resources continue to be provided for the future.  

Other Resource

US Fish and Wildlife Service: https://www.fws.gov

•          purpose is to work with the community to protect, conserve, and strengthen fish, plants and their habitats America’s future benefit

National Oceanic and Atmospheric Administration: http://www.noaa.gov

•     focuses on keeping the population informed of the changing environment from the sun to the depths of the ocean floor.

  

Work-Cited

https://ecos.fws.gov/docs/recovery_plan/Atlantic%20salmon%20draft%20recovery%20plan.pdf

http://www.nmfs.noaa.gov/pr/species/fish/atlantic-salmon.html

https://www.fws.gov/northeast/greenlake/images/atlantic_salmon_960x350.jpg

http://www.nmfs.noaa.gov/pr/species/fish/atlantic-salmon.html

https://www.nefsc.noaa.gov/press_release/pr2016/scispot/ss1607/

https://www.nefsc.noaa.gov/sos/spsyn/af/salmon/