Free-swimming northern elephant seals have low field metabolic rates that are sensitive to an increased cost of transport

Open Access Peer Reviewed Publication 2014

The Journal of Experimental Biology

Widely ranging marine predators often adopt stereotyped, energysaving behaviours to minimize the energetic cost of transport while maximizing energy gain. Environmental and anthropogenic disturbances can disrupt energy balance by prompting avoidance behaviours that increase transport costs, thereby decreasing foraging efficiency. We examined the ability of 12 free-ranging, juvenile northern elephant seals (Mirounga angustirostris) to mitigate the effects of experimentally increased transport costs by modifying their behaviour and/or energy use in a compensatory manner. Under normal locomotion, elephant seals had low energy requirements (106.5±28.2 kJ kg-1 day-1), approaching or even falling below predictions of basal requirements. Seals responded to a small increase in locomotion costs by spending more time resting between dives (149±44 s) compared with matched control treatments (102±11 s; P<0.01). Despite incurred costs, most other dive and transit behaviours were conserved across treatments, including fixed, rhythmic swimming gaits. Because of this, and because each flipper stroke had a predictable effect on total costs (P<0.001), total energy expenditure was strongly correlated with time spent at sea under both treatments (P<0.0001). These results suggest that transiting elephant seals have a limited capacity to modify their locomotory behaviour without increasing their transport costs. Based on this, we conclude that elephant seals and other ocean predators occupying similar niches may be particularly sensitive to increased transport costs incurred when avoiding anticipated disturbances.

Link To Publication

Similar Research

Anthropogenic sound and marine mammal health: measures of the nervous and immune systems before and after intense sound exposure

Pay-walled Journal Article 2004

Canadian Journal of Fisheries and Aquatic Sciences

Anthropogenic sound is a potential stressor for marine mammals that may affect health, as has been demonstrated in other mammals. Therefore, we have initiated investigations on...
Read More

A Brief Review of Anthropogenic Sound in the Oceans

Open Access Journal Article 2007

International Journal of Comparative Psychology

Sound in the oceans is generated by a variety of natural sources, such as breaking waves, rain, and marine animals, as well as a variety of...
Read More

Effect of anthropogenic low-frequency noise on the foraging ecology of Balaenoptera whales

Pay-walled Journal Article 2006

Animal Conservation

The human contribution to ambient noise in the ocean has increased over the past 50 years, and is dominated by low-frequency (LF) sound (frequencies <1000 Hz)...
Read More

Response and Responsibility: Regulating Noise Pollution in the Marine Environment

Pay-walled Journal Article 2007

Journal of International Wildlife Law and Policy

The ocean is becoming an increasingly noisy environment. With a rise in com-mercial shipping, resource extraction activities, and military-related activities,the underwater ocean environment is a virtual...
Read More

Influences of man-made noise and other human actions on cetacean behaviour

Pay-walled Journal Article 1995

Marine and Freshwater Behaviour and Physiology

Behavioral reactions of cetaceans to man-made noises are highly variable, ranging from attraction (e.g. bow riding by dolphins) or no response through short-term changes in behaviour...
Read More

International Regulation Of Transboundary Pollutants: The Emerging Challenge Of Ocean Noise

Open Access Journal Article 2001

Ocena and Coastal Law Journal

Transboundary pollution law poses the challenge of addressing environmental problems irrespective of boundaries in an international legal system that values, above all, territorial sovereignty of individual...
Read More

Determination of environmental sensitivity of acoustic propagation on continental shelves using an equivalent fluid parabolic equation model

Pay-walled Journal Article 1995

The Journal of the Acoustical Society of America

A coupled environment and acoustic prediction system was developed to evaluate the sensitivity of acoustic propagation on the continental shelf to water column and sediment properties....
Read More

Effects of underwater noise on auditory sensitivity of a cyprinid fish

Pay-walled Journal Article 2001

Hearing Research

The ability of a fish to interpret acoustic information in its environment is crucial for its survival. Thus, it is important to understand how underwater noise...
Read More

Effects of noise exposure on click detection and the temporal resolution ability of the goldfish auditory system

Pay-walled Journal Article 2005

Hearing Research

Hearing specialist fishes investigated so far revealed excellent temporal resolution abilities, enabling them to accurately process temporal patterns of sounds. Because noise is a growing environmental...
Read More

The effects of noise on the auditory sensitivity of the bluegill sunfish, Lepomis macrochirus

Pay-walled Journal Article 2002

Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology

As concerns about the effects of underwater anthropogenic noises on the auditory function of organisms increases, it is imperative to assess if all organisms are equally...
Read More