Photo: Zooplankton

Welcome to the zooplankton 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 zooplankton.

Concentrations of phytoplankton lead to an abundance of grazers or zooplankton. In the Pacific North Coast Integrated Management Area (PNCIMA), this is usually found in areas with pronounced changes in depth over a small distance. These 'bathymetric edges, such as the numerous underwater canyons and the edge of the continental shelf, are the primary areas where zooplankton like krill aggregate.

Zooplankton are the link to nearly all other marine animals. Many marine mammals, seabirds, and fish feed directly on the great abundance of zooplankton found here. The flesh of salmon gets its characteristic orange colour from pigments found in zooplankton.

Why are zooplankton important to humans?

Because of their valuable protein and oils, worldwide demand for zooplankton is on the rise. Satisfying this demand, however, will come at the expense of all higher animals in the food web, including humans. Zooplankton's ecological role is comparable to a lighting director in a theatre production — no one really notices their role, but if there is no light there is nothing to see. Zooplankton are increasingly being used as indicators for forecasting the abundance of fish and bird populations, and for tracking the impacts of climate change on ocean ecosystems. There is a small, tightly regulated fishery for krill in British Columbia.

What can we do to protect them?

With increasing demand for their valuable oils, we need to make sure Canada does not expand the krill fishery. There is growing concern that the increasing acidity of the world's oceans due to rising CO2 in the atmosphere could have a devastating impact on zooplankton and the food webs reliant on them, which is basically every marine food web on the planet. Much of the zooplankton in PNCIMA are krill or copepods, which are small animals related to the more familiar crab, shrimp and lobster. These zooplankton have shells made of calcium carbonate, a compound that dissolves under acidic conditions. The effects of ocean acidification are already being witnessed in North Pacific waters.

> Next destination: Kelp forests and seagrasses
> Previous destination: Phytoplankton

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