scholarly journals Habitat selection by hooded seals (Cystophora cristata) in the Northwest Atlantic Ocean

2012 ◽  
Vol 70 (1) ◽  
pp. 173-185 ◽  
Author(s):  
Julie M. Andersen ◽  
Yolanda F. Wiersma ◽  
Garry B. Stenson ◽  
Mike O. Hammill ◽  
Aqqalu Rosing-Asvid ◽  
...  
Keyword(s):  
Habitat Selection ◽  
Atlantic Ocean ◽  
Habitat Use ◽  
First Passage Time ◽  
Additive Model ◽  
Adult Males ◽  
Northwest Atlantic ◽  
Search Effort ◽  
Cystophora Cristata ◽  
Adult Females

Abstract Andersen, J. M., Wiersma, Y. F., Stenson, G. B., Hammill, M. O., Rosing-Asvid, A., and Skern-Maurizen, M. 2013. Habitat selection by hooded seals (Cystophora cristata) in the Northwest Atlantic Ocean. – ICES Journal of Marine Science, 70:173–185. We examined annual habitat use for 65 hooded seals (32 adult females, 17 adult males, and 16 juveniles) equipped with satellite relay data loggers (SRDLs) in spring or summer during five field seasons (2004–2008). A combined approach using first passage time (FPT) analysis and a generalized additive model (GAM) was applied to test for habitat selection, with a focus on environmental parameters of depth, slope, ice, sea surface temperature (SST), and chlorophyll. The models were run on adult males, adult females, and juveniles separately, and the results identified SST, depth, and chlorophyll as the most important factors influencing habitat selection across all categories. Furthermore, males and females preferred similar habitat conditions, but were separated geographically, and by depth, at various times of the year. Males appeared to be more localized in their habitat use patterns, focusing their search effort in areas of complex seabed relief such as Baffin Bay, Davis Strait, and the Flemish cap, while females concentrated their search effort along shelf areas (e.g. the Labrador shelf). These findings support our hypothesis that hooded seals prefer areas where topography and oceanographic processes create favourable foraging conditions.

scholarly journals Investigating Annual Diving Behaviour by Hooded Seals (Cystophora cristata) within the Northwest Atlantic Ocean

PLoS ONE ◽  
2013 ◽  
Vol 8 (11) ◽  
pp. e80438 ◽  
Author(s):  
Julie M. Andersen ◽  
Mette Skern-Mauritzen ◽  
Lars Boehme ◽  
Yolanda F. Wiersma ◽  
Aqqalu Rosing-Asvid ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
Diving Behaviour ◽  
Northwest Atlantic ◽  
Cystophora Cristata

Association of Social Classes of the Wallaroo, Macropus robustus (Marsupialia : Macropodidae)

1983 ◽  
Vol 10 (1) ◽  
pp. 39 ◽  
Author(s):  
RJ Taylor
Keyword(s):  
Habitat Use ◽  
New England ◽  
New South ◽  
Adaptive Significance ◽  
Social Classes ◽  
Adult Males ◽  
Adult Females ◽  
South Wales ◽  
The Social ◽  
Large Adult

The association of individuals of different social classes of the wallaroo was examined on two properties (Lana and Newholme) in the New England Tablelands of New South Wales. The density of wallaroos on Lana was seven times greater than that on Newholme. Individuals of different social classes differed in the extent to which they were found alone. More animals were seen alone on Newholme than on Lana but this increase was not uniform over the social classes. Individuals of different social classes did not associate at random. Association patterns differed for individuals in groups of different size. No differences in habitat use were found between different social classes during grazing periods; however, during sheltering periods a greater proportion of large adult males was found in areas with many rocks compared with medium adult males or adult females with young-at-foot. The adaptive significance of the pattern of association of social classes is discussed.

Additions to the ichthyofauna of the Tristan da Cunha Group, South Atlantic Ocean

Zootaxa ◽  
2005 ◽  
Vol 1072 (1) ◽  
pp. 27
Author(s):  
M. E. ANDERSON ◽  
D. L. STEIN ◽  
H. W. DETRICH
Keyword(s):  
Atlantic Ocean ◽  
Rare Species ◽  
Axial Skeleton ◽  
South Atlantic ◽  
South Atlantic Ocean ◽  
Adult Males ◽  
Undescribed Species ◽  
Walvis Ridge ◽  
Tristan Da Cunha ◽  
Adult Females

Specimens of two, possibly three, rare species of fishes were collected at the Tristan da Cunha Group toward the end of a 2004 South Atlantic cruise (ICEFISH). The dragonet Synchiropus valdiviae (Trunov, 1981), was previously known from only two adult males taken on Walvis Ridge. We collected two adult females and three juveniles, which are described here. The pearlfish Echiodon atopus Anderson, 2005, was recently described from a specimen collected north of Inaccessible Island. It differs from congeners in its high precaudal vertebral count, equivalent dorsal and anal rays anterior to vertebra 31 and other features of the axial skeleton and fins. Lastly, an unusual specimen of the rockfish genus Sebastes taken in a commercial lobster pot represents either a previously unreported variant of S. capensis or an undescribed species. It differs from the typical South Atlantic S. capensis in its coloration and lack of supraocular spines.

scholarly journals Drift Diving by Hooded Seals (Cystophora cristata) in the Northwest Atlantic Ocean

PLoS ONE ◽  
2014 ◽  
Vol 9 (7) ◽  
pp. e103072 ◽  
Author(s):  
Julie M. Andersen ◽  
Garry B. Stenson ◽  
Mette Skern-Maurizen ◽  
Yolanda F. Wiersma ◽  
Aqqalu Rosing-Asvid ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
Northwest Atlantic ◽  
Cystophora Cristata

Reproductive state leads to intraspecific habitat partitioning and survival differences in greater sage-grouse: implications for conservation

2018 ◽  
Vol 45 (2) ◽  
pp. 119 ◽  
Author(s):  
Kurt T. Smith ◽  
Jeffrey L. Beck ◽  
Christopher P. Kirol
Keyword(s):  
Habitat Selection ◽  
Habitat Use ◽  
Bird Species ◽  
Reproductive Investment ◽  
Population Persistence ◽  
Habitat Partitioning ◽  
Reproductive State ◽  
Sage Grouse ◽  
Brood Rearing ◽  
Adult Females

Context Inter- and intraspecific habitat partitioning is widespread across taxa, yet limited information is available on differences in intraspecific habitat selection by same-sex individuals among differing reproductive states. Understanding habitat selection by conspecifics of different reproductive states may help optimise conservation efforts, particularly for gallinaceous bird species such as greater sage-grouse (Centrocercus urophasianus), which are long-lived but have only moderate reproductive rates. Aims We predicted that habitat use differed between grouse under different reproductive states and that reproductive investment decreased survival of adults in summer. Methods We compared habitat characteristics used by brood-rearing and broodless female sage-grouse and evaluated the influence of reproductive investment and habitat use on survival of adult females. Key results We found that brood-rearing and broodless female sage-grouse partitioned habitat at micro- and macrohabitat scales. Broodless females were more likely to survive the summer. Conclusions Our findings suggest reproductive state variability in habitat selection by female sage-grouse. Broodless females were roosting and foraging in concealed habitats with intermediate visual obstruction and annual vegetation productivity, but less food forb availability compared with early and late brood-rearing females. In contrast, brood-rearing females likely selected more herbaceous understoreys to predictably maximise foraging opportunities and promote growth of their chicks, which appeared to mitigate the influence of reproductive costs on summer survival, particularly during the late brood-rearing period. Implications Survival of adult females is critical for population persistence of sage-grouse and other long-lived Galliformes, yet conservation efforts generally focus on habitats used during nesting and brood-rearing. Our results suggest that habitat partitioning is a potential risk-aversion strategy where individuals across different reproductive states likely select habitats to maximise their survival. Conservation efforts should focus on conserving habitats used by both brood-rearing and broodless sage-grouse to ensure population persistence.

Migration, overwintering, and reproductive patterns of Taricha granulosa on southern Vancouver Island

1974 ◽  
Vol 52 (4) ◽  
pp. 541-545 ◽  
Author(s):  
M. G. Oliver ◽  
H. M. McCurdy
Keyword(s):  
Habitat Selection ◽  
Reproductive Cycle ◽  
Vancouver Island ◽  
Adult Males ◽  
Taricha Granulosa ◽  
Reproductive Patterns ◽  
Nonbreeding Season ◽  
Adult Females ◽  
Reproductive Cycles

Sexual dichotomy in habitat selection during the nonbreeding season was studied in the rough-skinned newt Taricha granulosa from November 1970 to August 1973 on southern Vancouver Island. Field results show that in this area adult females normally migrate from breeding ponds to overwinter on land. Adult males normally remain permanently aquatic. Related observations on the reproductive cycle of T. granulosa show that females, who lay their eggs singly, deposit them for a period of a few days, followed by a period of nonegglaying. This process is repeated at intervals. Oviposition can occur from late April to July in this area. Females who were induced to ovulate in the laboratory each deposited three eggs per day for 5 days before opposition ceased. Thus the reproductive cycles of field and taboratory-acclimated females are correlated.

Multiple-colony winter habitat use by murres Uria spp. in the Northwest Atlantic Ocean: implications for marine risk assessment

2013 ◽  
Vol 472 ◽  
pp. 287-303 ◽  
Author(s):  
LA McFarlane Tranquilla ◽  
WA Montevecchi ◽  
A Hedd ◽  
DA Fifield ◽  
CM Burke ◽  
...  
Keyword(s):  
Risk Assessment ◽  
Atlantic Ocean ◽  
Habitat Use ◽  
Winter Habitat ◽  
Northwest Atlantic
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