Weddell Seal underwater calling rates during the winter and spring near Mawson Station, Antarctica

During the winter and spring of 2002, underwater calling rates were measured near mid-day on an opportunistic basis at 7 breeding sites and, at two breeding sites, over 24 hour periods once a month. The data were analysed with respect to reproductive season (early ice formation, prebreeding, pupping and mating) and if the recordings were made when it was dark or twilight/light.

Taken from the abstract of the paper referenced below:

Underwater vocalisation monitoring and surveys, both on ice and underwater, were used to determine if Weddell seals (Leptonychotes weddellii) near Mawson Station, Antarctica, remain under the fast ice during winter within close range of breeding sites. Daytime and nighttime underwater calling rates were examined at seven breeding sites during austral winter and spring to identify seasonal and diel patterns. Seals rarely hauled out at any of the sites during winter, although all cohorts (adult males, females, and juveniles) were observed underwater and surfacing at breathing holes throughout winter (June-September) and spring (October-December). Seal vocalisations were recorded during each sampling session throughout the study (n=102 daytime at seven sites collectively, and n=5 24-h samples at each of two sites). Mean daytime calling rate was low in mid-winter (July) (mean = 18.9 plus or minus 7.1 calls per minute) but increased monthly, reaching a peak during the breeding season (November) (mean = 62.6 plus or minus 15.7 calls per minute). Mean nighttime calling rate was high throughout the winter and early spring (July-October) with mean nocturnal calling rate in July (mean = 61.8 plus or minus 35.1 calls per minute) nearly equal to mean daytime calling rate in November (during 24-h daylight). Reduced vocal behaviour during winter daylight periods may result from animals utilising the limited daylight hours for nonvocal activities, possibly feeding.

The following study sites were among those used in this project (provided by Phil Rouget):

- Forbes site (identified as Site 6 in the paper) is located at Forbes Glacier (approx. 0.5 km to the west of the glacier tongue and approximately 200 meters offshore of the mainland). (67 degrees 35.256 minutes S, 62 degrees 16.756 minutes E)

- Kista site is located in the middle of Kista Strait (site 7 in the Marine Mammal Science paper). (67 degrees, minutes 33.840 S, 62 degrees 47.402, minutes E)

- SPA site was our site located just west of the western boundary of the SPA which itself is located west of Mawson and east of Forbes Glacier. (Site 2 in Marine Mammal Science paper). (67 degrees 35.179 S, 62 degrees 25.425 minutes E)

- McDonald Islands (or Rocks) was the site located North/NorthWest of Kista Strait, as it is named so on the Framens Mtn. Nautical Chart. From memory, it was approximately 12 km north/north west of Mawson Station. (This was site 5 in the Marine Mammal Science paper). (67 degrees 29.414 minutes S, 62 degrees 41.011 minutes E)

- Stewart Rocks (also named Sewart Rocks on an alternative map) is located due north of Mawson Station, also by about 12 km. (East of McDonald site, and North East of Kista). This was site 4 in the Marine Mammal Science paper. (67 degrees 29.933 minutes S, 62 degrees 51.765 minutes E)

- Anderson Rocks is an extensive group of rocky islets west of Auster Island (approximately 6-7 km offshore). This was site 3 in the Marine Mammal Science paper. (67 degrees 26.445 minutes S, 63 degrees 25.414 minutes E)

- SEAL MO was located just north of Macey Hut by about 2 km. This was site 1 in the Marine Mammal Science paper. (67 degrees 23.399 minutes S, 63 degrees 47.977 minutes E)

- Aside from SEAL MO and SPA, the names from all these sites are indicated in the Framnes Mountain Chart.

An image showing the locations of the fields sites is also part of the download file.

The fields in this dataset are:

Site

Period

Day

Calling rate

photoperiod

Sun time

Identification info

Alternate title: Weddell Seal underwater calling rates during the winter and spring near Mawson Station, Antarctica

Date (Publication): 2007-06-20

Edition: 1

Citation identifier

Dataset DOI

Title: Information and documentation - Digital object identifier system

Date (Publication): 2012-04-23

Citation identifier: ISO 26324:2012

Citation identifier: doi:10.4225/15/54D0480835B71

Originator

Terhune, J.T., Rouget, P.A. and Burton, H.

Publisher

Australian Antarctic Data Centre

Principal investigator

TERHUNE, JOHN MOORE

Department of Biology

PO Box 5050

University of New Brunswick

Saint John

New Brunswick

E2L 4L5

Canada

+1 506 648 5633

+1 506 648 5811 (facsimile)

Collaborator

TERHUNE, JOHN MOORE

Department of Biology

PO Box 5050

University of New Brunswick

Saint John

New Brunswick

E2L 4L5

Canada

+1 506 648 5633

+1 506 648 5811 (facsimile)

Collaborator

ROUGET, PHIL A

Department of Biology

Saint John

PO Box 5050

University of New Brunswick

New Brunswick

Canada

Collaborator

BURTON, HARRY

Australian Antarctic Division

203 Channel Highway

Kingston

Tasmania

7050

Australia

Name: CAASM Metadata

Website: https://data.aad.gov.au/metadata/records/ASAC_1132-1

Status: Completed

Custodian

AU/AADC > Australian Antarctic Data Centre, Australia - AADC, DATA OFFICER (DATA CENTER CONTACT)

Australian Antarctic Division

203 Channel Highway

Kingston

Tasmania

7050

Australia

+61 3 6232 3244

+61 3 6232 3351 (facsimile)

Topic category

Biota
Oceans

Extent

Description: Temporal Coverage

Temporal extent

TimePeriod: 2002-05-29 2002-12-11

Title: Weddell seal underwater calling rates during the winter and spring near Mawson Station, Antarctica.

Date (Publication): 2007

Edition: 23

Author

Rouget, P.A., Terhune, J.M. and Burton, H.R.

Name: Marine Mammal Science

Page: 508-523

Title: Diurnal and seasonal trends in the vocal behavioir of the Weddell seal (Leptonychotes weddellii).

Date (Publication): 2004

Author

Rouget, P.A.

Publisher

University of New Brunswick

Saint John

Name: M.Sc. thesis

Page: 120

Other citation details: NB, Canada