Tag Archives: fish

Chinook salmon (Oncorhynchus tshawytscha)

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Chinook salmon

The Chinook salmon is an important keystone species for the U.S. Pacific Northwest. It is a vital food source for a diversity of wildlife, including orca whales, bears, seals, and large birds of prey.

Chinook salmon is prized by people who harvest salmon both commercially and for sport. Chinook are the largest Pacific salmon species.

Big guys

On average, these fish are 3 feet long and weigh approximately 30 pounds. Some individuals can grow to over 5 feet long and 110 pounds!

Chinook salmon live about three to seven years. Juvenile salmon stay in freshwater habitat for the first year or so, before moving to the estuaries and then the open ocean. Estuaries provide a lot of food and nutrients to the developing salmon.

Return to breed

The fish spend approximately two to four years feeding in the ocean before returning to the spawning grounds to breed and die.

Endangered

The Chinook Salmon is on the U.S. Endangered Species List. The Sacramento River winter-run population in California is classified as endangered wherever it is found.

Other naturally spawned populations in California, Idaho, Oregon, and Washington are classified as threatened. Why the Chinook and other Pacific Northwest salmon have declined is no mystery.

4 H’s

The causes are known as “the four H’s”: harvest, habitat, hatcheries, and hydroelectric power.

Harvest refers to the overfishing by commercial fishing interests.

Habitat refers to degradation of a species home range, usually by pollutants. Another example would be increases in water sediments making a stream uninhabitable by the salmon or their eggs.

Captive-bred hatchery fish, released in the waterways used by native fish, compete and interbreed with the natives and weaken their stocks.

Hydroelectric dams have had perhaps the largest impact, blocking migration routes. Flood control and power generation were the original goals of these dams, rather than fish. As such, the dam construction changed the quality, quantity, rate of flow, temperature of the water, and species mix in rivers, lakes, and tributary streams.

Protection of Chinook salmon is crucial to maintain healthy Pacific Northwest ecosystems and to provide a delicious food source for years to come. 

Bald Eagle (Haliaeetus leucocephalus)

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There is a nest nearby. I can’t see it, but I know it is tucked high in the tall Douglas-fir overlooking the river.  

Photo from Oregon Dept. of Fish and Wildlife

Most Bald Eagle nests are within one-half mile of a body of water. After all fish is one of their favorite foods. The water, in this case, is a coastal shoreline and the Coquille River. Bald Eagles will also nest near bays, lakes, farm ponds, especially if they can find large trees, an unobstructed view of the water, and few humans.

Their shadows smoothly slide across the grass. Today they hunt.

Bald Eagles will hunt over large areas soaring up to 10,000 feet. In addition to fish, they will also take other animals such as birds, turtles, and mammals (like rabbits and rodents). They are not particularly fond of mammals, but will take them or mammal carrions.

Carrion, particularly in the winter, is frequently scavenged. They are considered to be an opportunistic predator meaning that they hunt when necessary and scavenge carrion when possible.

Every once in a while, they fly back to the nest clutching a large and noticeably heavy fish. Makes a weird shadow. Scares the little birds.

These large raptors are scary. They can sport a wingspan of up to 8 feet! Their body is just a few inches short of a yard. Adult birds can weigh upwards of 14 lbs. As with many birds, the females are larger than the males.

Bald Eagles will hunt other birds (such as geese and gulls). They are known to harass other eagles and Ospreys in an attempt to steal food from them. They are also known to occasionally steal food from other mammals and occasionally humans.

Big birds need big nests.

Bald Eagles build some of the largest nests of any bird. The size will depend on the supporting tree but are often 5-6 feet in diameter and 2-4 feet tall. The nest can weigh upwards of a ton! The largest recorded Bald Eagle nest was found in St. Petersburg, Florida. It measured nearly 9 ½ feet in diameter and just over 20 feet tall.

Building a nest is serious business and can take up to three months to build. These nests may be used over many years with additional materials being added each year. Sometimes ground nests, on cliff sides may be built.

One glance and you know what the little birds see.

Feathers of the adult Bald Eagle are quite distinctive with the white head and tail, brown body, with yellow beak, eyes, and feet. The distinctive color appears when the bird reaches four to five years of age. Both sexes have similar plumages.

Bald Eagles live a long time.

The oldest recorded wild bird, killed by a car in 2015, was at least 38 years old. Birds in captivity are known to live even longer.

Want to know more?

The Bald Eagle is one of the most studied North American birds and is the only sea-eagle found throughout North America. To learn more, visit the following references:
–Oregon Department of Fish and Wildlife, My ODFW “Raptors” (https://myodfw.com/wildlife-viewing/species/raptors)
–All About Birds, The Cornell Lab (https://www.allaboutbirds.org/guide/Bald_Eagle/…)
–Oregon Wild (https://oregonwild.org/wildlife/bald-eagle)
–USDI, Fish and Wildlife Service “Bald Eagle” (https://www.fws.gov/oregonfwo/articles.cfm?id=149489418)