Featured Research

from universities, journals, and other organizations

Humpback Whales' Dining Habits And Energy Costs Of Feasting On Tiny Prey, Revealed

Date:
November 27, 2008
Source:
University of British Columbia
Summary:
As most American families sit down to Thanksgiving dinner, a University of British Columbia researcher is revealing how one of the largest animals on earth feasts on the smallest of prey -- and at what cost.

Humpback whales, one of the largest animals on earth, feasts on the smallest of prey.
Credit: iStockphoto/Robert Friedman

As most American families sit down to Thanksgiving dinner, a University of British Columbia researcher is revealing how one of the largest animals on earth feasts on the smallest of prey – and at what cost.

Some large marine mammals are known for their extraordinarily long dive times. Elephant seals, for example, can stay underwater for an hour at a time by lowering their heartbeat and storing large amounts of oxygen in their muscles.

"Weighing up to 40 tons, humpback whales and their close relatives have relatively short dive times given their large body size," says UBC zoology PhD candidate Jeremy Goldbogen, whose study is featured on the cover of the current issue of The Journal of Experimental Biology. "Our study suggests that this has to do with the enormous energy costs of its unique foraging behaviours."

Humpbacks belong to a group of whales – called rorquals – that includes the fin whale and the blue whale, the largest animal that has ever lived. Characterized by an accordion-like blubber layer that goes from the snout to the naval, these whales take deep dives in search of dense patches of tiny zooplankton, such as krill or copepods.

While foraging, the whales literally drop their jaws during a high-speed dive – called a lunge – creating enormous drag akin to a race car driver opening a parachute. The drag forces the blubber to expand around a large volume of prey-laden water, which is then filtered out through a comb-like structure called baleen when the mouth closes.

Goldbogen and colleagues from the University of California, San Diego and Cascadia Research Collective, a non-profit organization in Washington, recorded the foraging behaviour of two humpback whales off the coast of California using a non-invasive, temporary digital tag that records depth, body angle and other acoustic data. After multiple tagging attempts, the team successfully recorded data over an eight-hour period; one whale performed 43 dives and 362 lunges while the other executed 15 dives and 89 lunges.

The team found that lunge-feeding requires a large amount of energy compared to other behaviours – humpback whales breathe three times harder after returning to the surface from a foraging dive than from singing. Lunge-feeding whales also spent half as much time under water compared to singing whales.

Not surprisingly, the team found that the longer the dive, the more lunges were taken – and more time and breaths were required before the next dive. The whales also stuck to the uppermost level of dense krill patches to maximize prey catch for its energy expenditure, according to the study.

By integrating tag data and hydrodynamic theory inspired from parachute inflation studies, Goldbogen now plans to compare lunge-feeding performance among blue, fin and humpback whales to determine whether the energy cost of a lunge is higher for bigger rorquals.

"We believe lunge feeding is related to the overall evolutionary and ecological success of rorquals, but the high energy cost may impose a physical limit on how big, and also how small, a whale can get."


Story Source:

The above story is based on materials provided by University of British Columbia. Note: Materials may be edited for content and length.


Cite This Page:

University of British Columbia. "Humpback Whales' Dining Habits And Energy Costs Of Feasting On Tiny Prey, Revealed." ScienceDaily. ScienceDaily, 27 November 2008. <www.sciencedaily.com/releases/2008/11/081127074620.htm>.
University of British Columbia. (2008, November 27). Humpback Whales' Dining Habits And Energy Costs Of Feasting On Tiny Prey, Revealed. ScienceDaily. Retrieved October 1, 2014 from www.sciencedaily.com/releases/2008/11/081127074620.htm
University of British Columbia. "Humpback Whales' Dining Habits And Energy Costs Of Feasting On Tiny Prey, Revealed." ScienceDaily. www.sciencedaily.com/releases/2008/11/081127074620.htm (accessed October 1, 2014).

Share This



More Plants & Animals News

Wednesday, October 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Newsy (Sep. 30, 2014) A new study published by the World Wide Fund for Nature found that more than half of the world's wildlife population has declined since 1970. Video provided by Newsy
Powered by NewsLook.com
Dolphins Might Use Earth's Magnetic Field As A GPS

Dolphins Might Use Earth's Magnetic Field As A GPS

Newsy (Sep. 30, 2014) A study released Monday suggests dolphins might be able to sense the Earth's magnetic field and possibly use it as a means of navigation. Video provided by Newsy
Powered by NewsLook.com
How To Battle Stink Bug Season

How To Battle Stink Bug Season

Newsy (Sep. 30, 2014) Homeowners in 33 states grapple with stink bugs moving indoors at this time of year. Here are a few tips to avoid stink bug infestations. Video provided by Newsy
Powered by NewsLook.com
California University Designs Sustainable Winery

California University Designs Sustainable Winery

Reuters - US Online Video (Sep. 27, 2014) Amid California's worst drought in decades, scientists at UC Davis design a sustainable winery that includes a water recycling system. Vanessa Johnston reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins