Fish and Invertebrates

The Georgia Basin is home to many fish and invertebrates, which make up the basis for aquatic (water) food webs.

ig_adamsriver1Invertebrates in the Georgia Basin range from the tiny shrimp-like copepods (crustaceans) to the prized Dungeness crab, as well as a variety of bivalve shellfish, such as clams and oysters.

Of the many fish living in freshwater (lakes and rivers) or saltwater (ocean) habitats in the Georgia Basin, salmon are one of the most fascinating types as they migrate between these two environments during their life. Fish that do this are called anadromous (a-na-dro-mus).

Salmon show how everything is connected in nature, from the bottom of the food chain to the top, and between terrestrial, freshwater and saltwater habitats. When salmon return to rivers and lakes to spawn, wildlife, including grizzly bears, catch them and often carry them deep into the forest. Uneaten salmon parts then breakdown and release important nutrients that are used by plants and trees to grow.

Each fish and invertebrate species in the Georgia Basin can tell a story about pollution because of their special life history features and habitat use, for example:

  • Some species are big (salmon), some are small (copepods).
  • Some live a very long time (clams), others do not (crab).
  • Some need a lot of space to live (herring), while some cling to a single rock for their whole life (mussel).
  • Some, such as salmon, live in more than one habitat.

Some are grazers and eat algae (sea urchins), some filter plankton out of the water (clams), some eat other animals (salmon), and some are scavengers and feed on dead or dying plants and animals (crabs).

While all of these creatures may be exposed to pollution, some are at higher risk for pollution effects than others. For example, those that are bigger, live a long time, live in many habitats where more pollution sources occur, feed higher on the food chain, or never move and are continuously exposed to pollutants, could be at a higher risk.