What do Energy Pyramids tell us? The importance of the Spotted Owl

Energy Pyramids show the flow of energy through an ecosystem Ecologists study energy pyramids

3 rd level consumers mostly carnivores & some omnivores 2 nd level consumer carnivores & omnivores 1 st level consumer herbivores Producers: green plants make their own energy from sunlight 10,000 Kcal 1000 Kcal 100 Kcal 10 Kcal 1 Kcal An energy pyramid from the Andrews

10,000 Kcal 1000 Kcal 100 Kcal 10 Kcal 0.1% 1% 10% 100% 1 Kcal 0.01% When an owl eats a flying squirrel it uses about 90% of the calories to live— move, digest, produce body heat, reproduce and escape from predators. When a frog eats a cricket or a cricket eats a plant, they use 90% of those calories to move, digest, produce body heat, reproduce and escape from predators.

Bushy tailed wood rat Red- backed voles Deer Mouse Chipmunk Red Tree Vole Flying Squirrels are about half the owl’s diet Spotted Owls need a large home range. Home range is the name ecologists give the amount of living area animals need to hunt enough prey to survive. You can tell how healthy an ecosystem is by the number of 3 rd level consumers living there. If there is not enough energy (prey) in an ecosystem the area won’t be able to support 3rd level consumers. Brush Rabbit Snow Shoe Hare Spotted Owls are 3 rd level consumers

Spotted Owls mate for life. They live about 10 years. Mating pairs usually return to the same nest every summer to raise their young. When winter comes, the young leave the nest and mating pairs separate to find their own home range because prey is scarce.

Young Spotted Owls are born in nests at the top of tall snags. They become fledglings when they are old enough to leave the nest and fly After two months the fledglings leave home and find their own mate and home range. around the nest area.

Northern Goshawk Great Horned Owl Barred Owls Spotted Owl predators and competitors include the Northern Goshawk and the Great Horned Owl and The Barred Owl. These birds attack Spotted Owls, prey on their young, compete for prey and try to drive them out of their home range.