The Salmon Connection
Salmon are a keystone species in the Fraser River, which means there are many different organisms that depend upon them for survival. Click the photos of each species to explore the many ways salmon are connected to other animals (and even plants!) throughout the Fraser Watershed. Then, click the buttons at the top and bottom of the circle to see what happens if there are more or fewer salmon in the water. How do the populations of the other organisms change?
KEYSTONE SPECIES
Think of keystone species as the glue that holds an ecosystem (a community of living things) together. Keystone species can be any living thing that has a big effect on many other living things that share its ecosystem. This connection is so important that, if the population of a keystone species were to change, the entire ecosystem would change, too. Keystone species can come in all shapes and sizes – from beavers to wolves, and even some types of plants! Each keystone species plays a very important role in its ecosystem’s food web.
Over 130 species of plants and animals rely on Pacific salmon for survival. Without this important keystone species, the Fraser River ecosystem will look very different!
Salmon
The five species of Pacific salmon – chum, coho, Chinook, pink, and sockeye—all play an important part in the Fraser River ecosystem. These amazing fish begin their lives in freshwater, migrate to the salty Pacific Ocean, then return back to freshwater to reproduce. In each stage of their lives, they can be predators or prey—and sometimes both! Learn more about their connections to other species by clicking on the circles that surround the salmon.
Zooplankton
Tiny zooplankton are connected to salmon in a few different ways. Young salmon fry will feed on zooplankton – they are an important source of energy for the growing salmon. Then, after migrating salmon die, their bodies become a food source for the zooplankton.
Western Red Cedar
Even plants rely on salmon! When a bear catches a salmon, it will bring the fish inland to eat. The bears don’t eat the entire salmon, though – what’s leftover can serve as food for scavengers, and the remaining parts break down on the forest floor, leaving behind soil filled with nutrients that help trees grow. Without salmon, these important, ocean-rich nutrients would never make it to the forests.
Mosquitoes
In the early stages of life, salmon fry and smolts feed upon insects, like mosquitoes, and their eggs. Without salmon to eat up these insects, mosquito populations will rise!
River Otters
River otters are opportunistic feeders and excellent hunters. They have a keen sense of smell and will follow migrating salmon back to shallow water, where they become easier to hunt. Spawning salmon make a great meal for a family of river otters, considering the salmon can be larger than the otters themselves!
ORCAS
Off the coast of British Columbia lives a population of orcas, known as the southern resident killer whales. These whales love to eat salmon—specifically, Chinook! They live in this region year-round and need a healthy population of Chinook salmon in order to survive.
BEARS
Salmon are an important food source for grizzly and black bears. A single bear can eat up to 15 salmon each day! A healthy salmon population means a healthy bear population (and fewer bears rooting around in garbage cans looking for food!)
Sandpiper
Salmon fry and smolts are an important source of food for migratory birds, like sandpipers. The Fraser estuary is an important habitat for migratory birds—if salmon disappeared from this area, birds like sandpipers wouldn’t have enough food to fuel their long migrations.
