Show simple item record

dc.contributor.authorRiordan, Julie
dc.contributor.authorJohnston, Greg
dc.date.accessioned2017-05-03T14:40:48Z
dc.date.available2017-05-03T14:40:48Z
dc.date.issued2013
dc.date.modified2014-06-18T05:57:56Z
dc.identifier.issn15244695
dc.identifier.doi10.1675/063.036.0114
dc.identifier.urihttp://hdl.handle.net/10072/60573
dc.description.abstractBlack-faced Cormorants (Phalacrocorax fuscescens) are endemic to marine environments in southern Australia and little is known of their biology. Development of a reliable and practical method for sexing adult birds in the field is necessary to aid research into their behavior and life-history. Eleven measurements from museum specimens (27 male; 31 female) were used to document sexual dimorphism in Black-faced Cormorants using discriminant function analyses (DFA). A simultaneous DFA correctly sexed 81% of birds, while a stepwise DFA correctly sexed 85% of birds based on two measurements (bill length and mid tail length). However, terminal wear of the retrices make this measurement unreliable. A logistic regression using bill length correctly predicted the sex of 78% of individuals. Black-faced Cormorants with a bill = 76 mm long are likely female and = 77 mm long are likely male, therefore providing a reliable method for assigning sex in the field. Black-faced Cormorants exhibit the same pattern of sexual dimorphism found in all other cormorants studied to date: males are larger, more robust and have a longer bill compared to the smaller, relatively gracile and shorter-billed females. The use of this general rule to assign sex to adult Black-faced Cormorants was confirmed through the observation of mating behavior. Therefore, this study provides a dependable and practicable technique for assigning sex in the field without the need to capture birds and disturb their behavior.
dc.description.peerreviewedYes
dc.description.publicationstatusYes
dc.languageEnglish
dc.language.isoeng
dc.publisherWaterbird Society
dc.publisher.placeUnited States
dc.relation.ispartofstudentpublicationN
dc.relation.ispartofpagefrom94
dc.relation.ispartofpageto101
dc.relation.ispartofissue1
dc.relation.ispartofjournalWaterbirds
dc.relation.ispartofvolume36
dc.rights.retentionY
dc.subject.fieldofresearchZoology not elsewhere classified
dc.subject.fieldofresearchZoology
dc.subject.fieldofresearchcode060899
dc.subject.fieldofresearchcode0608
dc.titleMorphological Sex Determination in Black-Faced Cormorants (Phalacrocorax fuscescens)
dc.typeJournal article
dc.type.descriptionC1 - Articles
dc.type.codeC - Journal Articles
gro.facultyGriffith Sciences, Griffith School of Environment
gro.hasfulltextNo Full Text
gro.griffith.authorRiordan, Julie A.


Files in this item

FilesSizeFormatView

There are no files associated with this item.

This item appears in the following Collection(s)

  • Journal articles
    Contains articles published by Griffith authors in scholarly journals.

Show simple item record