Mutualistic Relationships:
* Seabirds: Harbor seals and seabirds often share feeding grounds. The seals may flush fish from the seabed, making them easier for the birds to catch. In return, the birds may alert the seals to potential dangers, like approaching predators.
* Crabs and Other Invertebrates: Some species of crabs and invertebrates benefit from the seals' feeding activities. They may scavenge on scraps left behind by seals, or find new food sources exposed by their foraging.
Competitive Relationships:
* Other Pinnipeds: Harbor seals compete with other pinnipeds, such as gray seals and harbor porpoises, for food and territory.
* Fish: Harbor seals are apex predators in their ecosystem, and they can significantly impact fish populations.
Predatory Relationships:
* Orcas: Orcas are the primary predators of harbor seals. They can hunt and kill seals in open water or on land.
* Great White Sharks: In some areas, great white sharks are also predators of harbor seals.
* Polar Bears: While not typically found in the same areas, polar bears may prey on harbor seals if their ranges overlap.
Other Relationships:
* Parasites: Like all animals, harbor seals can be host to various parasites, such as roundworms, flukes, and mites.
* Commensalism: Some species, like barnacles, may attach themselves to harbor seals without harming them, benefiting from the seal's movement and access to food.
It's important to note that the specific nature and strength of these relationships can vary depending on the location and the time of year.
Overall, harbor seals play a vital role in their ecosystem, interacting with a diverse array of species in both beneficial and competitive ways. Their presence and activities significantly influence the dynamics of their marine environment.