Foraging trip strategies and habitat use during late pup rearing by lactating Australian fur seals

2011 ◽  
Vol 59 (4) ◽  
pp. 216 ◽  
Author(s):  
Roger Kirkwood ◽  
John P. Y. Arnould
Keyword(s):  
Habitat Use ◽  
Marine Mammal ◽  
Hot Spots ◽  
Marine Reserves ◽  
Central Place ◽  
Shelf Edge ◽  
Fur Seals ◽  
Eastern Australia ◽  
Management Perspective ◽  
Latitudinal Range

Australian fur seals (Arctocephalus pusillus doriferus) are the most conspicuous and abundant marine mammal in shelf waters of south-eastern Australia. To successfully rear offspring, the females must encounter sufficient prey on each foraging trip out of a central place for periods up to11 months each year. We investigated foraging trip strategies and habitat use by the females in three winter–spring periods, 2001–03, from four colonies that span the species’ latitudinal range and contribute 80% of pup production. Trip durations of 37 females averaged 6.1 ± 0.5 (s.e.) days, although >90% of the seal’s time at sea was spent <150 km travel (<2 days) away. Most females exhibited strong fidelities to individually preferred hot-spots. Females from colonies adjacent to productive shelf-edge waters generally had shorter trips, had smaller ranges, foraged closer to colonies and exhibited less diversity in trip strategies than did those from colonies more distant from a shelf-edge. From a management perspective, there was minimal overlap (<1%) between where females foraged and a system of marine reserves established in 2007, suggesting that habitats visited by lactating Australian fur seals currently receive minimal legislative protection.

Cumulative and Synergistic Effects of Physical, Biological, and Acoustic Signals on Marine Mammal Habitat Use (PSU)

2008 ◽  
Author(s):  
Jennifer L. Miksis-Olds ◽  
Jeffrey A. Nystuen
Keyword(s):  
Habitat Use ◽  
Marine Mammal ◽  
Synergistic Effects ◽  
Acoustic Signals

scholarly journals Diving deep into trouble: the role of foraging strategy and morphology in adapting to a changing environment

2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Monique Ladds ◽  
David Rosen ◽  
Carling Gerlinsky ◽  
David Slip ◽  
Robert Harcourt
Keyword(s):  
Foraging Strategy ◽  
Central Place ◽  
Dive Duration ◽  
Foraging Strategies ◽  
Body Morphology ◽  
Sea Lions ◽  
Fur Seals ◽  
Adequate Food ◽  
Physiological Capacity ◽  
Total Body Oxygen

Abstract Physiology places constraints on an animal’s ability to forage and those unable to adapt to changing conditions may face increased challenges to reproduce and survive. As the global marine environment continues to change, small, air-breathing, endothermic marine predators such as otariids (fur seals and sea lions) and particularly females, who are constrained by central place foraging during breeding, may experience increased difficulties in successfully obtaining adequate food resources. We explored whether physiological limits of female otariids may be innately related to body morphology (fur seals vs sea lions) and/or dictate foraging strategies (epipelagic vs mesopelagic or benthic). We conducted a systematic review of the increased body of literature since the original reviews of Costa et al. (When does physiology limit the foraging behaviour of freely diving mammals? Int Congr Ser 2004;1275:359–366) and Arnould and Costa (Sea lions in drag, fur seals incognito: insights from the otariid deviants. In Sea Lions of the World Fairbanks. Alaska Sea Grant College Program, Alaska, USA, pp. 309–324, 2006) on behavioural (dive duration and depth) and physiological (total body oxygen stores and diving metabolic rates) parameters. We estimated calculated aerobic dive limit (cADL—estimated duration of aerobic dives) for species and used simulations to predict the proportion of dives that exceeded the cADL. We tested whether body morphology or foraging strategy was the primary predictor of these behavioural and physiological characteristics. We found that the foraging strategy compared to morphology was a better predictor of most parameters, including whether a species was more likely to exceed their cADL during a dive and the ratio of dive time to cADL. This suggests that benthic and mesopelagic divers are more likely to be foraging at their physiological capacity. For species operating near their physiological capacity (regularly exceeding their cADL), the ability to switch strategies is limited as the cost of foraging deeper and longer is disproportionally high, unless it is accompanied by physiological adaptations. It is proposed that some otariids may not have the ability to switch foraging strategies and so be unable adapt to a changing oceanic ecosystem.

Modelling habitat use suggests static spatial exclusion zones are a non-optimal management tool for a highly mobile marine mammal

2020 ◽  
Vol 167 (5) ◽  
Author(s):  
Sarah L. Dwyer ◽  
Matthew D. M. Pawley ◽  
Deanna M. Clement ◽  
Karen A. Stockin
Keyword(s):  
Habitat Use ◽  
Marine Mammal ◽  
Management Tool ◽  
Optimal Management ◽  
Spatial Exclusion

At-sea movements and habitat use of adult male Australian fur seals (Arctocephalus pusillus doriferus)

2006 ◽  
Vol 84 (12) ◽  
pp. 1781-1788 ◽  
Author(s):  
Roger Kirkwood ◽  
Michael Lynch ◽  
Nick Gales ◽  
Peter Dann ◽  
Michael Sumner
Keyword(s):  
Habitat Use ◽  
Continental Shelf ◽  
Adult Male ◽  
Maximum Distance ◽  
Commercial Fisheries ◽  
Southeastern Australia ◽  
Foraging Area ◽  
Fur Seals ◽  
Water Columns ◽  
Foraging Ranges

Foraging by adult male otariids, a demographic component that often interacts with commercial fisheries, are poorly known. To assess movement patterns and habitat use, nine adult male Australian fur seals ( Arctocephalus pusillus doriferus Wood Jones, 1925) from Seal Rocks, in northern Bass Strait, southeastern Australia, were tracked for periods ranging from 66 to 223 d during 1999–2001. Mean ± SD at-sea and on-land durations were 6.9 ± 2.1 d (range 2.3–10.3 d, n = 9 seals) and 2.4 ± 0.9 d (range 0.8–4.1 d), respectively. All seals foraged almost exclusively in continental shelf waters and mostly (65%–97% of time at sea) in water columns that were between 40 and 100 m deep. Six of nine seals tracked for >30 d spent 64%–98% of their time-at-sea foraging at distances <200 km from Seal Rocks, although the maximum distance achieved from the colony was 1208 km. The seals’ foraging ranges overlapped with the ranges of operation of virtually all fin-fish fisheries in southeastern Australia, but fisheries overlap was low in the most frequented foraging area of central-western Bass Strait.

Maximizing surveillance through spatial characterization of marine mammal stranding hot spots

2020 ◽  
Vol 36 (4) ◽  
pp. 1083-1096
Author(s):  
Jennifer K. Olson ◽  
John Aschoff ◽  
Alice Goble ◽  
Shawn Larson ◽  
Joseph K. Gaydos
Keyword(s):  
Marine Mammal ◽  
Hot Spots ◽  
Spatial Characterization

Edge geometry influences patch-level habitat use by an edge specialist in south-eastern Australia

2008 ◽  
Vol 23 (4) ◽  
pp. 377-389 ◽  
Author(s):  
Rick S. Taylor ◽  
Joanne M. Oldland ◽  
Michael F. Clarke
Keyword(s):  
Habitat Use ◽  
South Eastern ◽  
Edge Geometry ◽  
Eastern Australia ◽  
South Eastern Australia

Habitat use and movements of Australian grayling (Prototroctes maraena) in a Victorian coastal stream

2018 ◽  
Vol 69 (8) ◽  
pp. 1259 ◽  
Author(s):  
D. R. Dawson ◽  
W. M. Koster
Keyword(s):  
Habitat Use ◽  
Conservation Management ◽  
Radio Telemetry ◽  
Management Strategies ◽  
Movement Ecology ◽  
Ecological Requirements ◽  
Management Actions ◽  
Eastern Australia ◽  
The World ◽  
Australian Grayling

Riverine fishes are among the most imperilled fauna in the world; however, for many species, there is little or no understanding of their ecological requirements. The Australian grayling (Prototroctes maraena) is a small diadromous fish endemic to rivers in south-eastern Australia that has declined considerably in range and abundance and is listed as threatened nationally. To improve understanding of the species’ movement ecology and to inform the development of conservation management actions, we examined the day-to-day movements and habitat use of Australian grayling (n=7) over 8 weeks by using radio-telemetry. Tagged individuals of Australian grayling typically occupied restricted (i.e. tens to hundreds of metres) reaches of stream, and were mostly located in moderate- to fast-flowing habitats (i.e. glide or run), although, at night, use of slower-flowing habitats (i.e. pools) increased. They also undertook longer-distance downstream movements during a period of increased streamflow. Incorporation of such information into management strategies has the potential to improve our capacity to maintain or re-instate the conditions required to conserve and restore Australian grayling populations.

scholarly journals Correcting Positional Errors in Shore-Based Theodolite Measurements of Animals at Sea

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Ophélie Sagnol ◽  
Femke Reitsma ◽  
Christoph Richter ◽  
Laurence H. Field
Keyword(s):  
New Zealand ◽  
Habitat Use ◽  
Marine Mammal ◽  
Positional Information ◽  
Physeter Macrocephalus ◽  
Sperm Whales ◽  
Vertical Angle ◽  
Position Accuracy ◽  
Wide Range ◽  
The Difference

Determining the position of animals at sea can be particularly difficult and yet, accurate range and position of animals at sea are essential to answer a wide range of biological questions. Shore-based theodolite techniques have been used in a number of studies to examine marine mammal movement patterns and habitat use, offering reliable position measurements. In this study we explored the accuracy of theodolite measurements by comparing positional information of the same objects using two independent techniques: a shore-based theodolite station and an onboard GPS over a range of 25 km from the shore-based station. The technique was developed to study the habitat use of sperm whales (Physeter macrocephalus) off Kaikoura, New Zealand. We observed that the position accuracy fell rapidly with an increase in range from the shore-based station. Results showed that the horizontal angle was accurately determined, but this was not the case for the vertical angle. We calibrated the position of objects at sea with a regression-based correction to fit the difference in distance between simultaneously recorded theodolite fixes and GPS positions. This approach revealed the necessity to calibrate theodolite measurements with objects at sea of known position.

scholarly journals Oceanographic conditions associated with white shark (Carcharodon carcharias) habitat use along eastern Australia

2020 ◽  
Author(s):  
KA Lee ◽  
PA Butcher ◽  
RG Harcourt ◽  
TA Patterson ◽  
VM Peddemors ◽  
...  
Keyword(s):  
Habitat Use ◽  
White Shark ◽  
Carcharodon Carcharias ◽  
Eastern Australia ◽  
Oceanographic Conditions

scholarly journals Influence of environmental variation on spatial distribution and habitat-use in a benthic foraging marine predator

2021 ◽  
Vol 8 (10) ◽  
Author(s):  
Cassie N. Speakman ◽  
Andrew J. Hoskins ◽  
Mark A. Hindell ◽  
Daniel P. Costa ◽  
Jason R. Hartog ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Habitat Use ◽  
Large Scale ◽  
Environmental Variability ◽  
Southern Oscillation ◽  
Environmental Variation ◽  
Climate Indices ◽  
Marine Systems ◽  
Marine Predators ◽  
Eastern Australia

The highly dynamic nature of the marine environment can have a substantial influence on the foraging behaviour and spatial distribution of marine predators, particularly in pelagic marine systems. However, knowledge of the susceptibility of benthic marine predators to environmental variability is limited. This study investigated the influence of local-scale environmental conditions and large-scale climate indices on the spatial distribution and habitat use in the benthic foraging Australian fur seal ( Arctocephalus pusillus doriferus ; AUFS). Female AUFS provisioning pups were instrumented with GPS or ARGOS platform terminal transmitter tags during the austral winters of 2001–2019 at Kanowna Island, south-eastern Australia. Individuals were most susceptible to changes in the Southern Oscillation Index that measures the strength of the El Niño Southern Oscillation, with larger foraging ranges, greater distances travelled and more dispersed movement associated with 1-yr lagged La Niña-like conditions. Additionally, the total distance travelled was negatively correlated with the current year sea surface temperature and 1-yr lagged Indian Ocean Dipole, and positively correlated with 1-yr lagged chlorophyll- a concentration. These results suggest that environmental variation may influence the spatial distribution and availability of prey, even within benthic marine systems.

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