Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Salmon and other fish predators rely on 'no guts, no glory' survival tactic

16.09.2011
The phrase "no guts, no glory" doesn't just apply to athletes who are striving to excel.

Salmon and other fish predators take the adage literally, by having up to three times the "gut" capacity they need on a daily basis just so they can "glory" when prey is abundant, University of Washington researchers have discovered.


Bluegill forage on snails in Florida.
Credit: Jonathan Armstrong

It's a previously unrecognized survival tactic that might apply to other top predators, such as wolves, lions and bears, according to Jonathan Armstrong, a UW doctoral student in aquatic and fishery sciences and lead author of a letter published recently in the journal Nature.

"The predatory fish we examined have the guts to consume two- to three-times the amount of food that they regularly encounter. This much excess capacity suggests predator-prey encounters are far patchier – or random – than assumed in biology and that binge-feeding enables predators to survive despite regular periods of famine," Armstrong said. Co-author on the paper is Daniel Schindler, UW professor of aquatic and fishery sciences.

"Guts are really expensive organs in terms of metabolism," Armstrong said. For instance, maintaining a gut can require 30 to 40 percent of the blood pumped by an animal's heart.

Some animals have some capacity to grow or shrink their guts in response to changing conditions. For example, the digestive organs of birds that are about to migrate expand so they can eat more and fatten up. This is followed by a period when their guts atrophy and then, freed of the baggage of heavy guts, the birds take off.

That and results from lab studies led some scientists to assume that predators eliminate excess digestive capacity to save energy in times of famine. But the UW findings show that many fish species maintain a huge gut, which enables them to capitalize on unpredictable pulses of food.

"For predator fish, the world is a slot machine – sometimes they stumble upon small meals and other times they hit the jackpot. It's just not as predictable as some have thought," Armstrong said.

"Unlike some other animals, fish can't just hoard their food behind a rock in the stream and eat it later. They need to binge during the good times so that they can grow and build energy reserves to survive the bad times."

Armstrong and Schindler hope that their results can help with ecological models used in conservation and management.

"Ecosystem models typically assume relatively constant interactions between predator and prey but our results suggest such interactions are extremely patchy. We're excited to see if including this ecological realism might improve the predictions of these models."

The work was funded by the UW School of Aquatic and Fishery Sciences, National Science Foundation and the Gordon and Betty Moore Foundation.

For more information:

Armstrong, 541-840-6017, jonny5armstrong@gmail.com

Possible websites:

Armstrong http://fish.washington.edu/news/newsletter/sprsum_2011/studentprofiles.html#armstrong

UW School of Aquatic and Fishery Sciences http://www.fish.washington.edu/index.html

Abstract Nature letter http://www.nature.com/nature/journal/v476/n7358/full/nature10240.html?WT.ec_id=NATURE-20110804

Daniel Schindler http://fish.washington.edu/research/schindlerlab/index.html

National Science Foundation http://www.nsf.gov/

Gordon and Betty Moore Foundation http://www.moore.org/

Sandra Hines | EurekAlert!
Further information:
http://www.uw.edu

More articles from Ecology, The Environment and Conservation:

nachricht Dry landscapes can increase disease transmission
20.06.2018 | Forschungsverbund Berlin e.V.

nachricht 100 % Organic Farming in Bhutan – a Realistic Target?
15.06.2018 | Humboldt-Universität zu Berlin

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Graphene assembled film shows higher thermal conductivity than graphite film

22.06.2018 | Materials Sciences

Fast rising bedrock below West Antarctica reveals an extremely fluid Earth mantle

22.06.2018 | Earth Sciences

Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View

22.06.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>