Keystone species are animals that play such an essential role in their environment, that if they were no longer here, the ecosystem would drastically change for the worse. They have an enormous effect within an ecosystem, not necessarily through sheer size, number or biomass, but because of the pivotal roles they play. They are so important, in fact, that policies are made to guide their habitat management.
Nine Important Keystone Species in Oregon
and what they do that makes them so important
Coyotes limit mesocarnivore populations and increase bird diversity and abundance, keep rodent and rabbit populations in check, control disease transmission, and as scavengers, they provide an ecological service by helping to keep our communities clean of carrion.
Even though there are, reportedly only 16 wolf packs in Oregon, our Wolves are important in regulating prey populations. They enable many other species of plants and animals to flourish. In this regard, wolves initiate a domino effect – “touching” songbirds, beaver, fish, and butterflies.
- Sea otters
exert top-down pressure via predation on sea urchins, which are grazers upon kelp. As urchin density decreases from sea otter predation, so does the grazing pressure on kelp and as a result kelp forests flourish in the presence of sea otters.
play a fundamental role in creating and maintaining a diversity of flora and fauna associated with the Pacific Northwest’s streams, rivers, and wetlands, and protecting them is key to restoring and maintaining healthy waterways in Oregon.
- Brown Bear
they contribute to nutrient cycling of salmon and carrion, indirectly assist with seed dispersal over large areas, regulate prey species such as ungulates, which in turn leads to increased plant biomass, and assist with soil aeration when digging for roots and rodents.
- Canadian Lynx
are a keystone species and could assist with controlling deer numbers, which would increase biodiversity and habitat structure in our woodlands.
- Pacific salmon
Anadromous salmon are a “keystone” species in both aquatic and terrestrial environments, meaning they influence survival or reproduction of other species. Even as carcasses, salmon help ensure overwinter survival of many freshwater fish by providing nutrients at summer’s end.
Two Important Keystone Species that are returning (or possibly returning) to Oregon
Sea Otter photo credit: unsplash.com