Q:

Why do salmon swim upstream?

A:

Quick Answer

Salmon return to rivers from the ocean and swim upstream to their original hatching place to lay and fertilize their eggs. Swimming upstream is hard work, and only the strongest complete the journey and spawn the next generation of salmon.

Know More
Why do salmon swim upstream?
Credit: Daniel J Cox Photographer's Choice Getty Images

Full Answer

Each species of salmon follows its own schedule of return to the birth stream for reproducing. Experts believe that an inborn sense of smell guides each species of salmon to its original hatching grounds. When the fish leave the salt water of the ocean and enter the fresh water of the stream, they stop eating. Spawning is the last thing salmon do before they die.

Learn More
Sources:

Related Questions

  • Q:

    Are lionfish freshwater or seawater inhabitants?

    A:

    Lionfish are seawater inhabitants native to the warmer waters of the Pacific Ocean and the Indian Ocean. They were reported in the waters around southern Florida in 1985, and as of 2014, they have been sighted along the east coast of the Atlantic Ocean as far north as New York.

    Full Answer >
    Filed Under:
  • Q:

    What is a bristlenose catfish?

    A:

    Bristlenose catfish are algae-eating fish found in the tropics of South America. Males grow to 15 centimeters long, and females grow to 12 centimeters. Bristlenose catfish are also known as bushynose catfish, bristlenose pleco and bushynose pleco.

    Full Answer >
    Filed Under:
  • Q:

    What do lionfish eat?

    A:

    Lionfish eat fish and invertebrates. Juveniles eat mostly invertebrates, with fewer fish in their diet; adult lionfish eat mostly fish. They have been shown to cannibalize each other in the wild, with larger lionfish eating smaller lionfish. Their eating habits disrupt ecosystems by competing with native fish and overfeeding on species that control algae.

    Full Answer >
    Filed Under:
  • Q:

    How are fish born?

    A:

    There are three types of fish reproduction. The first and most common one, found in 97% of fish, is ovaparity. The other two types are oviviparity and viviparity. As in humans, male fish produce sperm, and female fish produce eggs in their ovaries.

    Full Answer >
    Filed Under:

Explore