The Importance of Herring for The Great Bear Sea

Herring are small forage fish up to thirty centimeters long and 500 grams in weight. The Pacific herring is silver and has unspined fins and a deep caudal fin. The life cycle of herring is unique and includes spawning, feeding, migration and maturation stages.

Herring Spawning

Pacific herring spawn in the late winter and early spring from about mid-February to early April. The adhesive eggs are deposited on vegetation and rocks along the shoreline between the high and low tide marks. Photo credit: Gerald Corsi on iStock

Herring gather in large schools in shallow waters or estuaries during their spawning period. A single spawning event can stretch over many kilometers of shoreline. 18% of British Columbia’s coast has been classified as herring spawning habitat. Females lay their sticky eggs on seaweed, sea grass, or rocks, which are then fertilized by the milt (sperm) male herring release in the water. The milt turns the water in the spawning ground a distinctive chalky white. A single mature female herring can spawn 20,000 eggs annually, with the average lifespan of herring being ten years. After hatching, juvenile herring feed mainly on zooplankton until they reach maturity at two years of age. Mature herring migrate to deeper water, where they feed on various organisms such as crustaceans, mollusks, worms and other small fish.

Killer whales or orcas hunt herring using a coordinated strategy. The whale first gathers the herring, then it then slaps at them with its tail to debilitate its prey. Photo credit: Brian Skerry on National Geographic

Herring and The Great Bear Sea

Herring are one of the most important keystone species on the Great Bear Coast and are considered the foundation of the coastal food web. Their importance for the coastal food web begins when they are eggs, as the spawning grounds become a weeks-long feast for many marine species and coastal land mammals, including black bears, wolves, sea lions, seals, humpback whales, gray whales, orcas, and birds. They converge on the spawning grounds to feed on herring and their eggs. The herring spawn is so important to the Great Bear Coast ecosystem that surf scoters and gray whales time their northward migrations to feast on it. In the wider Great Bear Sea, herring are an essential part of the diet of many fish. For example, the diets of Chinook Salmon, Coho Salmon, and Lingcod consist of 62%, 58%, and 71% herring respectively. This means that herring transfer the energy from the plankton they feed on to the entire Great Bear Coast ecosystem.

Why are Herring Important for Communities on The Great Bear Coast?

Herring are the foundation of the Great Bear Coast communities, with First Nations’ harvesting of this fish going back at least 10,000 years. In fact, “throughout the Pacific Northwest, herring bones are among the most abundant fish remains found in ancient coastal settlements, indicating that herring were a critical food resource.” One traditional herring harvesting technique First Nations use is the sustainable roe on kelp. Instead of taking the entire fish, roe on kelp involves harvesting the roe from hemlock branches, seaweed or kelp. Herring roe is a source of protein, iron, vitamin B1, and riboflavin for coastal First Nations.

First Nations practicing sustainable herring roe harvesting
To harvest their herring roe, the Kitasoo Xai’xais practice sustainable harvesting methods that collect the eggs but do not kill the fish. Photo credit: Kitasoo Xai’xais Nation

Herring Decline

Under the guidance of the DFO, Pacific herring numbers have decreased up to 96% in some areas in the last fifty years. There are several reasons for this decline, but researchers have identified commercial overfishing and DFO mismanagement as the main culprits. The most detrimental type of commercial fishing for herring is the sac roe herring fishery, as the entire fish is harvested just for the roe. The remaining 90% of the catch biomass, including the entire male, is processed into dog food, fertilizer, and feed for farmed salmon.

The DFO has consistently made bad decisions about herring fisheries. One flaw in the DFO approach to herring stock management is that it lacks essential spatial considerations. First Nations have always understood that herring form distinct sub-stocks, each connected to specific spawning areas, resulting in First Nations herring management taking place at the level of individual spawning sites. Because the DFO has used a much larger regional spatial approach, four of the five Pacific herring fishing grounds collapsed following the 2015 opening. The 2022 opening of the Strait of Georgia herring fishery was disastrous and illustrates that the DFO once again overestimated herring biomass. First Nations on the coast, such as the Heiltsuk, have consistently advocated for sustainable herring fisheries. However, the DFO has constantly gone against the science and management agreements with First Nations. 

 “The most parsimonious explanation for the difference between the modern pattern of variability in herring abundance and the long-term archaeological record is the onset of industrial-scale commercial fishing.”

McKechnie et al.

Protecting Herring

A seals face is covered in herring roe
“Everything out there, the salmon, the seals, the sea lions, all types of fish up to the whales rely on the herring to survive.” – Tsawout Hereditary Chief Eric Pelkey. Photo credit: Mars Media on Reddit

The only way forward to ensure that herring are protected is the establishment of the Great Bear Sea Marine Protected Network. The Great Bear Sea MPA Network will cover about 30% of the sea’s area and consist mostly of existing MPAs. Establishing MPAs at critical spawning areas will allow herring populations to recover. When keystone species like herring thrive, so will other marine animals and, by extension, the marine ecosystem as a whole. A healthy marine ecosystem is critical not only for future biodiversity, but also for the sustainability of coastal economies – it’s one more reason to support the Great Bear Sea MPA Network.

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