Occurrence

Blue Whale Study aerial surveys, southern Australia 2002-2007

Latest version published by OBIS-SEAMAP on 24 April 2021 OBIS-SEAMAP
Original provider: Blue Whale Study Inc. Dataset credits: Blue Whale Study Inc. Abstract: Blue whales <i>Balaenoptera musculus</i> 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... More
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Publication date:
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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.

Data Records

The data in this occurrence resource has been published as a Darwin Core Archive (DwC-A), which is a standardized format for sharing biodiversity data as a set of one or more data tables. The core data table contains 408 records.

This IPT archives the data and thus serves as the data repository. The data and resource metadata are available for download in the downloads section. The versions table lists other versions of the resource that have been made publicly available and allows tracking changes made to the resource over time.

Downloads

Download the latest version of this resource data as a Darwin Core Archive (DwC-A) or the resource metadata as EML or RTF:

Data as a DwC-A file download 408 records in English (38 kB) - Update frequency: not planned
Metadata as an EML file download in English (13 kB)
Metadata as an RTF file download in English (13 kB)

Versions

The table below shows only published versions of the resource that are publicly accessible.

How to cite

Researchers should cite this work as follows:

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.

Rights

Researchers should respect the following rights statement:

The publisher and rights holder of this work is OBIS-SEAMAP. This work is licensed under a Creative Commons Attribution Non Commercial (CC-BY-NC) 4.0 License.

GBIF Registration

This resource has been registered with GBIF, and assigned the following GBIF UUID: e38a459a-06c4-4056-8f2c-4f0d2fc38605.  OBIS-SEAMAP publishes this resource, and is itself registered in GBIF as a data publisher endorsed by Ocean Biodiversity Information System.

Keywords

Occurrence,Aircraft,Sightings,pygmy blue whales; Observation; Occurrence

External data

The resource data is also available in other formats

OBIS-SEAMAP Dataset Page http://seamap.env.duke.edu/dataset/971 UTF-8 Interactive map
FGDC Metadata http://seamap.env.duke.edu/dataset/971/xml UTF-8 XML

Contacts

Who created the resource:

Peter Gill
Primary contact
Blue Whale Study Inc.
http://www.bluewhalestudy.org

Who can answer questions about the resource:

Peter Gill
Primary contact
Blue Whale Study Inc.
http://www.bluewhalestudy.org

Who filled in the metadata:

OBIS-SEAMAP
Marine Geospatial Ecology Lab, Duke University
A328 LSRC building
27708 Durham
NC
US
http://seamap.env.duke.edu

Who else was associated with the resource:

Distributor
OBIS-SEAMAP
Marine Geospatial Ecology Lab, Duke University
A328 LSRC building
27708 Durham
NC
US
http://seamap.env.duke.edu
Owner
Peter Gill
Primary contact
Blue Whale Study Inc.
http://www.bluewhalestudy.org

Geographic Coverage

Australia

Bounding Coordinates South West [-39.383, 134.058], North East [-35.053, 143.303]

Taxonomic Coverage

Scientific names are based on the Integrated Taxonomic Information System (ITIS).

Subspecies  Balaenoptera musculus brevicauda (Pygmy blue whale)

Temporal Coverage

Start Date / End Date 2002-01-19 / 2007-05-16

Project Data

No Description available

Title Blue Whale Study aerial surveys, southern Australia 2002-2007
Funding NA

The personnel involved in the project:

Owner
Peter Gill

Sampling Methods

NA

Study Extent NA

Method step description:

  1. NA

Collection Data

Collection Name zd_971
Collection Identifier zd_971
Parent Collection Identifier OBIS-SEAMAP

Additional Metadata

marine, harvested by iOBIS

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.&lt;br&gt;&lt;br&gt; 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.
Alternative Identifiers http://ipt.env.duke.edu/resource?r=zd_971