Big fish | Marine planning and conservation | Oceans | Science & policy | Marine planning and conservation | Issues
Photo: Big fish

Big fish like this basking shark showed constitute a major part of PNCIMA's economic resources. (Credit: Greg Skomal)

Welcome to the big fish page of the 'I Am Fish' tour. These three guiding words, I am fish, appear simple. But they reflect an ancient and extraordinary web of biological activity that connects humans with the ocean.

I am big fish

One fish, two fish, red fish, blue fish — over 400 species of fish use the waters of the Pacific North Coast Integrated Management Area (PNCIMA). While many are small but approximately 50 of them are big. Some are very big, such as the highly endangered basking shark, the second largest fish in the world, and the renowned predatory white shark.

Many of the big fish species — including sole, halibut, lingcod, sablefish, rockfish, spiny dogfish and skate — end up being eaten by the most dominant marine predator in PNCIMA, humans. Scientists are finding that a fish's body size is the best predictor for its risk of endangerment. Big fish are typically old lived, slow growing, late maturing and heavily exploited by humans. We have species of rockfish that can live over 200 years. In the time span of a seafood dinner, decades of growth and survival is often being consumed. Meanwhile, the rockfish will have eaten thousands of meals itself during its life cycle and have avoided being the meal of yet a bigger fish or marine mammal.

Why are big fish important to humans?

Around 40,000 tonnes of big fish are pulled out of PNCIMA's waters every year. That amounts to approximately a pickup truck load a minute, 24 hours a day, for 70 days. The 20-odd big fish species netted in this catch constitute PNCIMA's most valuable economic resource. Equally in demand by the numerous fishing lodges and guides who profit from fishing, these fish employ people and provide sustenance to coastal communities that rely on them as a primary source of food. Big fish also have intrinsic value by contributing to the ecological and evolutionary processes that sustain PNCIMA's ecosystem.

What can we do to protect them?

There is no single human activity in the world's oceans that has as much direct impact on the ecosystem as fishing. Many big fish like halibut, sablefish and rockfish are the target of commercial fisheries in PNCIMA. There are many fish species here that are recognized as 'threatened' or of 'special concern' by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC).

While new technology and practices enable sustainable fishing practices, they often require substantial reforms to management that include gear restrictions, reduced catches and closed areas. Sustainable fishing also requires a comprehensive survey and assessment program to keep track of fish populations. Many fisheries in PNCIMA have undergone significant reforms in recent years towards becoming more sustainable.

> Next destination: Salmon
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http://www.davidsuzuki.org/issues/oceans/science/marine-planning-and-conservation/big-fish/

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