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Foraging ecology of southern elephant seals in relation to the bathymetry and productivity of the Southern Ocean
It is suggested that the physiological requirements of feeding and digestion reduced the aerobic dive limit of elephant seals, and long distance travel to relocatable hydrographic or topographical features, such as shelf breaks, may allow large predators to locate prey more consistently than from mid-ocean searches. Expand
One-step N2-dilution technique for calibrating open-circuit VO2 measuring systems.
A simple one-step procedure that eliminates the need to calibrate the O2 analyzer or measure the flow past the animal is described for calibrating an open-flow respirometry system. The technique isExpand
Blubber and buoyancy: monitoring the body condition of free-ranging seals using simple dive characteristics
A mechanistic model based on body compositions and morphometrics measured in the field, published values for the density of seawater and various body components, and values of drag coefficients for objects of different shapes was used to examine the theoretical relationships between drift rate and body composition and carried out a sensitivity analysis to quantify errors and biases caused by varying model parameters. Expand
How long should a dive last? A simple model of foraging decisions by breath-hold divers in a patchy environment
Abstract Although diving birds and mammals can withstand extended periods under water, field studies show that most perform mainly short, aerobic dives. Theoretical studies of diving have implicitlyExpand
The Argos satellite system is commonly used to track and relay behavioral data from marine mammals, but their underwater habit results in a high proportion of locations of non-guaranteed accuracyExpand
A simple new algorithm to filter marine mammal Argos locations
During recent decades satellite telemetry using the Argos system has been used extensively to track many species of marine mammals. However, the aquatic behavior of most of these species results in aExpand
Technical Note: Animal-borne CTD-Satellite Relay Data Loggers for real-time oceanographic data collection
Abstract. The increasing need for continuous monitoring of the world oceans has stimulated the development of a range of autonomous sampling platforms. One novel addition to these approaches is aExpand
Energetics and mechanics of terrestrial locomotion. IV. Total mechanical energy changes as a function of speed and body size in birds and mammals.
It is suggested that the intrinsic velocity of shortening of the active muscle motor units and the rate at which the muscles are turned on and off are the most important factors in determining the metabolic cost of constant-speed locomotion. Expand
Measurement of the body composition of living gray seals by hydrogen isotope dilution.
The body composition of living gray seals (Halichoerus grypus) can be accurately predicted from a two-step model that involves measurement of total body water (TBW) by 2H or 3H dilution andExpand
Estimating space‐use and habitat preference from wildlife telemetry data
This work proposes a logistic, mixed-effects approach that uses generalized additive transformations of the environmental covariates and is fitted to a response data-set comprising the telemetry and simulated observations, under a case-control design, and concludes that flexible empirical models can capture the environmental relationships that shape population distributions. Expand