Here we have an ecosystem, with biotic and abiotic factors, such as the bear and the rocks.
One such factor, are these fish, who live their lifes in the river. They are a food source for the local population of bears.
The bear, who is a consumer, looks for a meal in the river.
In order for the fish to survive, they eat kelp in the water, which uses photosynthesis to produce their energy.
In another part of the community, the woodpecker feeds on worms that it digs up from the ground. In this instance, the animal was a carnivore, but it normally eats both plants and smaller animals, making it an overall omnivore.
It's simply amazing to see how much biodiversity can be contained in such a seemingly simple ecosystem.