Description
Original provider:
Blue Whale Study Inc.
Dataset credits:
Blue Whale Study Inc.
Abstract:
Blue whales Balaenoptera musculus aggregate to feed in a regional upwelling system during November–May between the Great Australian Bight (GAB) and Bass Strait. We analyzed sightings from aerial surveys over 6 upwelling seasons (2001–02 to 2006–07) to assess within-season patterns of blue whale habitat selection, distribution, and relative abundance. Habitat variables were modelled using a general linear model (GLM) that ranked sea surface temperature (SST) and sea
surface chlorophyll (SSC) of equal importance, followed by depth, distance to shore, SSC gradient, distance to shelf break, and SST gradient. Further discrimination by hierarchical partitioning indicated that SST accounted for 84.4% of variation in blue whale presence explained by the model, and
that probability of sightings increased with increasing SST. The large study area was resolved into 3 zones showing diversity of habitat from the shallow narrow shelf and associated surface upwelling of the central zone, to the relatively deep upper slope waters, broad shelf and variable upwelling of
the western zone, and the intermediate features of the eastern zone. Density kernel estimation showed a trend in distribution from the west during November–December, spreading south-eastward along the shelf throughout the central and eastern zones during January–April, with the central zone most consistently utilized. Encounter rates in central and eastern zones peaked in February, coinciding with peak upwelling intensity and primary productivity. Blue whales avoided inshore upwelling centers, selecting SST ~1°C cooler than remotely sensed ambient SST. Whales selected
significantly higher SSC in the central and eastern zones than the western zone, where relative abundance was extremely variable. Most animals departed from the feeding ground by late April.
Purpose:
A primary objective of the present study was to use modelling (i.e., general linear model [GLM]) to assess the relative importance of a range of biophysical habitat variables in explaining whale distribution (see
Redfern et al. 2006 for a review of cetacean habitat modelling). To do this we used blue whale sighting data from aerial surveys over 6 upwelling seasons, in combination with bathymetric, remote sensing, and temperature logger data. Another objective was to explain within-season patterns of distribution and
relative abundance of foraging blue whales in this upwelling system using density kernel estimation and monthly variabililty in encounter rates. Furthermore, the present study presented an opportunity to assess whether the Bonney Upwelling surface plume, representing a shoaling of the thermocline rarely observed in blue whale feeding grounds elsewhere, provided insights into relationships between whales and upwelling in this region.
Reference: Redfern, J.V., M.C. Ferguson, E.A. Becker, K.D. Hyrenbach et al. 2006. Techniques for cetacean-habitat modelling.
Marine Ecological Progress Series 310:271–295.
Supplemental information:
[2015-06-04] The identification of the species is updated from Balaenoptera musculus to Balaenoptera musculus brevicauda.
Enregistrements de données
Les données de cette ressource occurrence ont été publiées sous forme d'une Archive Darwin Core (Darwin Core Archive ou DwC-A), le format standard pour partager des données de biodiversité en tant qu'ensemble d'un ou plusieurs tableurs de données. Le tableur de données du cœur de standard (core) contient 408 enregistrements.
Cet IPT archive les données et sert donc de dépôt de données. Les données et métadonnées de la ressource sont disponibles pour téléchargement dans la section téléchargements. Le tableau des versions liste les autres versions de chaque ressource rendues disponibles de façon publique et permet de tracer les modifications apportées à la ressource au fil du temps.
Versions
Le tableau ci-dessous n'affiche que les versions publiées de la ressource accessibles publiquement.
Comment citer
Les chercheurs doivent citer cette ressource comme suit:
Gill, P. 2015. Blue Whale Study aerial surveys, southern Australia 2002-2007. Data downloaded from OBIS-SEAMAP (http://seamap.env.duke.edu/dataset/971) on yyyy-mm-dd.
Droits
Les chercheurs doivent respecter la déclaration de droits suivante:
L’éditeur et détenteur des droits de cette ressource est OBIS-SEAMAP. Ce travail est sous licence Creative Commons Attribution Non Commercial (CC-BY-NC) 4.0.
Enregistrement GBIF
Cette ressource a été enregistrée sur le portail GBIF, et possède l'UUID GBIF suivante : e38a459a-06c4-4056-8f2c-4f0d2fc38605. OBIS-SEAMAP publie cette ressource, et est enregistré dans le GBIF comme éditeur de données avec l'approbation du Ocean Biodiversity Information System.
Mots-clé
Occurrence,Aircraft,Sightings,pygmy blue whales; Observation; Occurrence
Données externes
Les données de la ressource sont disponibles dans d'autres formats
OBIS-SEAMAP Dataset Page | http://seamap.env.duke.edu/dataset/971 UTF-8 Interactive map |
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FGDC Metadata | http://seamap.env.duke.edu/dataset/971/xml UTF-8 XML |
Contacts
- Propriétaire ●
- Créateur ●
- Personne De Contact
- Fournisseur Des Métadonnées ●
- Distributeur
Couverture géographique
Australia
Enveloppe géographique | Sud Ouest [-39,383, 134,058], Nord Est [-35,053, 143,303] |
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Couverture taxonomique
Scientific names are based on the Integrated Taxonomic Information System (ITIS).
Subspecies | Balaenoptera musculus brevicauda (Pygmy blue whale) |
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Couverture temporelle
Date de début / Date de fin | 2002-01-19 / 2007-05-16 |
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Données sur le projet
Pas de description disponible
Titre | Blue Whale Study aerial surveys, southern Australia 2002-2007 |
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Financement | NA |
Les personnes impliquées dans le projet:
- Propriétaire
Méthodes d'échantillonnage
NA
Etendue de l'étude | NA |
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Description des étapes de la méthode:
- NA
Données de collection
Nom de la collection | zd_971 |
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Identifiant de collection | zd_971 |
Identifiant de la collection parente | OBIS-SEAMAP |
Métadonnées additionnelles
marine, harvested by iOBIS
Objet | A primary objective of the present study was to use modelling (i.e., general linear model [GLM]) to assess the relative importance of a range of biophysical habitat variables in explaining whale distribution (see
Redfern et al. 2006 for a review of cetacean habitat modelling). To do this we used blue whale sighting data from aerial surveys over 6 upwelling seasons, in combination with bathymetric, remote sensing, and temperature logger data. Another objective was to explain within-season patterns of distribution and
relative abundance of foraging blue whales in this upwelling system using density kernel estimation and monthly variabililty in encounter rates. Furthermore, the present study presented an opportunity to assess whether the Bonney Upwelling surface plume, representing a shoaling of the thermocline rarely observed in blue whale feeding grounds elsewhere, provided insights into relationships between whales and upwelling in this region. Reference: Redfern, J.V., M.C. Ferguson, E.A. Becker, K.D. Hyrenbach et al. 2006. Techniques for cetacean-habitat modelling. Marine Ecological Progress Series 310:271–295. |
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Identifiants alternatifs | http://ipt.env.duke.edu/resource?r=zd_971 |