Farmed salmon is endangering access to local fishes for poorer communities, warns study

Sub : Env

Sec: Species in news

Context:

Impact of Farmed Salmon Demand on Coastal Communities and Fisheries
Study published in Science Advances, October 16, 2024.

Key Findings:

The increasing demand for farmed salmon is impacting global coastal communities by limiting their access to affordable local fish like sardines and anchovies. These small fish are often diverted to produce fishmeal and fish oil (FMFO), primarily used as feed for farmed fish.
Implications for Coastal Communities:
- Local Deprivation: Many reduction fisheries operate in poor coastal regions, depriving communities of fish that are crucial for their sustenance and livelihoods.
- Global Impact: This raises concerns about the sustainability of the aquaculture industry‘s dependence on FMFO, especially in regions heavily reliant on small pelagic fish.
Fish-In-Fish-Out (FIFO) Ratio:
- Industry Practices: The study critiques the misleading use of the FIFO ratio, which measures how much wild fish is needed to produce farmed fish. By averaging feed inputs for herbivores and carnivores, the ratio conceals the high feed demands of carnivorous fish like salmon.
- Rising Demand for Fish Oil: Fish oil is a limited resource, heavily used in salmon farming. In 2020, farmed Atlantic salmon alone accounted for 60% of global fish oil consumption, with salmon farms now supplying 70% of the world’s salmon.

Challenges Ahead:

Climate Change: Fish populations, including Peruvian anchoveta, are declining due to climate change, particularly in warmer waters where fish contain less oil.
Overfishing Juveniles: Poor fisheries management is leading to higher juvenile fish catches, which reduces oil yields and threatens stock sustainability.

Reduction Fisheries:

Reduction fisheries are fisheries that “reduce,” or process their catch, into fishmeal and fish oil. They rely largely on small and medium-sized pelagic species; that is, fish found in the upper layers of the open sea, such as menhaden, anchovies, and sardines.
12 of the top 20 global fisheries (by volume) are reduction fisheries, where fish are processed into FMFO.
These fisheries exploit forage fish such as anchovies and sardines, which make up 26% of global fish catches by volume.
The largest reduction fishery, by far, is that for Peruvian anchoveta. The catch from some fisheries, such as the anchoveta in Peru or Gulf menhaden in the US are almost exclusively used for reduction purposes.

Salmon:

Salmon is a common food fish classified as an oily fish with a rich content of protein and omega-3 fatty acids.
Norway is a major producer of farmed and wild salmon, accounting for more than 50% of global salmon production.
Farmed and wild salmon differ only slightly in terms of food quality and safety, with farmed salmon having lower content of environmental contaminants and wild salmon having a higher content of omega-3 fatty acids.

Sardines:

Sardines (“pilchards”) are a nutrient-rich, small, oily fish widely consumed by humans and as forage fish by larger fish species, seabirds and marine mammals.
Sardines are a source of omega-3 fatty acids.

Peruvian anchoveta:

The Peruvian anchoveta (Engraulis ringens) is a species of fish of the anchovy family, Engraulidae, from the Southeast Pacific Ocean.
It is one of the most commercially important fish species in the world, with annual harvests varying between 3.14 and 8.32 million tonnes from 2010 to 2021.