Repository logo
 
Publication

Sex differences in residency patterns of Risso's dolphins (Grampus griseus) in the Azores : causes and management implications

dc.contributor.authorHartman, Karin L.
dc.contributor.authorFernandez, Marc
dc.contributor.authorWittich, Anja
dc.contributor.authorAzevedo, José M. N.
dc.date.accessioned2017-05-25T12:33:17Z
dc.date.available2017-05-25T12:33:17Z
dc.date.issued2015
dc.description.abstractKnowledge of the residency patterns of marine mammals is an important element for management and conservation strategies. Here we investigate a population of Grampus griseus off Pico Island, Azores. Our data set covers the period 2004–2007, based on at-sea observations of 1,250 individually identified animals, 303 of known or assumed sex. Using photo identification and GPS locations we calculated mean monthly sighting rates and lagged identification rates to analyze temporal patterns, and estimated kernel density to study the home range. Our results show site fidelity and relatively restricted home ranges, which corroborate the existence of a resident population on the study site. We further document sex differences, including a higher number of males present in the area at any given time but females staying for longer consecutive periods, and male home ranges with significantly less overlap than those of females. These observations are consistent with a mating system based on multimale pods defending areas where females periodically return. We hypothesize that squid distribution is a major factor in structuring these patterns. These findings reinforce the need for a precautionary management approach that would include limiting pressure from commercial activities.en
dc.description.versioninfo:eu-repo/semantics/publishedVersionpt_PT
dc.identifier.citationHartman, K.L., Fernandez, M., Wittich, A., & Azevedo, J.M.N. (2015). Sex differences in residency patterns of Risso's dolphins (Grampus griseus) in the Azores: causes and management implications. "Marine Mammal Science", 31(3), 1153-1167. DOI:10.1111/mms.12209pt_PT
dc.identifier.doi10.1111/mms.12209pt_PT
dc.identifier.issn1748-7692
dc.identifier.urihttp://hdl.handle.net/10400.3/4171
dc.language.isoengpt_PT
dc.peerreviewedyespt_PT
dc.publisherWileypt_PT
dc.subjectGrampus griseuspt_PT
dc.subjectResidency Patternsen
dc.subjectSex Differencesen
dc.subjectSite Fidelityen
dc.subjectHome Rangeen
dc.titleSex differences in residency patterns of Risso's dolphins (Grampus griseus) in the Azores : causes and management implicationsen
dc.typejournal article
dspace.entity.typePublication
oaire.citation.endPage1167pt_PT
oaire.citation.issue3pt_PT
oaire.citation.startPage1153pt_PT
oaire.citation.titleMarine Mammal Scienceen
oaire.citation.volume31pt_PT
rcaap.rightsrestrictedAccesspt_PT
rcaap.typearticlept_PT

Files

Original bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
2015_Hartman_et_al Sex differences in residency patterns.pdf
Size:
606.29 KB
Format:
Adobe Portable Document Format
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.73 KB
Format:
Item-specific license agreed upon to submission
Description: