Nav: Home

Young salmon may leap to 'oust the louse'

August 10, 2018

A study by Simon Fraser University aquatic ecologists Emma Atkinson and John Reynolds reveals that young salmon may jump out of water to remove sea lice.

"Ideas about why fish leap include getting over obstacles during their upstream migration as adults, catching food and avoiding predators," says Atkinson.

"However, these reasons may not apply to young salmon since their diet is composed almost exclusively of underwater zooplankton and their tendency is to scatter rather than leap when escaping from predators."

Atkinson hypothesized that the leaping behaviour could be the fish's way of removing parasitic sea lice, which is a common condition for wild and penned salmon off the B.C. coast. Heavy sea-louse infestation is correlated with reduced growth, impaired swimming and competitive foraging ability for young salmon.

To test her hypothesis, Atkinson and her team caught wild juvenile sockeye salmon during their coastal migration away from the Fraser River. They held the fish in flow-through net-pen enclosures, half of which were covered with netting to prevent leaping and the other half were left uncovered to allow leaping. After three days, the team counted the lice on each fish.

The researchers found that, on average, the salmon that were allowed to leap in the uncovered pen had 22 per cent fewer sea lice compared to those that weren't allowed to leap in the covered pen.

The researchers also found that it may take more than 50 leaps for a young salmon to dislodge a sea lice, which Atkinson acknowledges is a substantial amount of energy to expend. She says these costs may be offset by the benefits of successfully removing sea lice, but will have to be investigated in another study.
-end-
Atkinson's study was recently published in the Journal of Fish Biology.

Simon Fraser University

Related Salmon Articles:

What does drought mean for endangered California salmon?
Droughts threatens California's endangered salmon population -- but pools that serve as drought refuges could make the difference between life and death for these vulnerable fish.
Salmon provide nutrients to Alaskan streambanks
Nutrient cycling of stream ecosystems dependent on portion of salmons' lifecycle.
Melting glaciers will challenge some salmon populations and benefit others
A new Simon Fraser University-led study looking at the effects that glacier retreat will have on western North American Pacific salmon predicts that while some salmon populations may struggle, others may benefit.
Bigger doesn't mean better for hatchery-released salmon
A recent study in the Ecological Society of America's journal Ecosphere examines hatchery practices in regards to how Chinook salmon hatcheries in the PNW are affecting wild populations over the past decades.
Salmon get a major athletic boost via a single enzyme
A single enzyme anchored to the walls of salmons' blood vessels helps reduce how hard their hearts have to work during exercise by up to 27%.
Salmon are shrinking and it shows in their genes
Male salmon are maturing earlier and becoming smaller, and it shows in their genes.
Young salmon may leap to 'oust the louse'
A study by Simon Fraser University aquatic ecologists Emma Atkinson and John Reynolds reveals that young salmon may jump out of water to remove sea lice.
Fishy chemicals in farmed salmon
The American Chemical Society journal Environmental Science & Technology featured research by Carla Ng, assistant professor of civil and environmental engineering at Pitt's Swanson School of Engineering, on the cover of its June 19 issue.
A little water could make a big difference for endangered salmon
A trickle of water flowing through a stream could mean life or death for endangered coho salmon in coastal California.
Coho salmon die, chum salmon survive in stormwater runoff research
In a recent paper published in the journal Environmental Pollution, scientists found that coho salmon became sick and nearly died, within just a few hours of exposure to polluted stormwater.
More Salmon News and Salmon Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Our Relationship With Water
We need water to live. But with rising seas and so many lacking clean water – water is in crisis and so are we. This hour, TED speakers explore ideas around restoring our relationship with water. Guests on the show include legal scholar Kelsey Leonard, artist LaToya Ruby Frazier, and community organizer Colette Pichon Battle.
Now Playing: Science for the People

#568 Poker Face Psychology
Anyone who's seen pop culture depictions of poker might think statistics and math is the only way to get ahead. But no, there's psychology too. Author Maria Konnikova took her Ph.D. in psychology to the poker table, and turned out to be good. So good, she went pro in poker, and learned all about her own biases on the way. We're talking about her new book "The Biggest Bluff: How I Learned to Pay Attention, Master Myself, and Win".
Now Playing: Radiolab

Uncounted
First things first: our very own Latif Nasser has an exciting new show on Netflix. He talks to Jad about the hidden forces of the world that connect us all. Then, with an eye on the upcoming election, we take a look back: at two pieces from More Perfect Season 3 about Constitutional amendments that determine who gets to vote. Former Radiolab producer Julia Longoria takes us to Washington, D.C. The capital is at the heart of our democracy, but it's not a state, and it wasn't until the 23rd Amendment that its people got the right to vote for president. But that still left DC without full representation in Congress; D.C. sends a "non-voting delegate" to the House. Julia profiles that delegate, Congresswoman Eleanor Holmes Norton, and her unique approach to fighting for power in a virtually powerless role. Second, Radiolab producer Sarah Qari looks at a current fight to lower the US voting age to 16 that harkens back to the fight for the 26th Amendment in the 1960s. Eighteen-year-olds at the time argued that if they were old enough to be drafted to fight in the War, they were old enough to have a voice in our democracy. But what about today, when even younger Americans are finding themselves at the center of national political debates? Does it mean we should lower the voting age even further? This episode was reported and produced by Julia Longoria and Sarah Qari. Check out Latif Nasser's new Netflix show Connected here. Support Radiolab today at Radiolab.org/donate.