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  • Underwater vocalisations of Weddell seals were recorded at Casey (1997) and Davis (1992 and 1997) Antarctica. The goal of the study was to determine if it would be possible to identify geographic variations between the Casey and Davis seals using easily measured, narrow bandwidth calls (and not broadband or very short duration calls). Two observers measured the starting and ending frequency (Hz), duration (msec) and number of elements (discrete sounds) of four categories of calls; long duration trills, shorter descending frequency whistles, ascending frequency whistles and constant frequency mews. The statistical analyses considered all calls per base, single and multiple element calls, and individual call types. Except for trills, discriminant function analysis indicated less variation between the call attributes from Davis in 1992 and 1997 than between either of the Davis data sets and Casey 1997. The data set contains measures from 2966 calls; approximately 1000 calls per base and year. Up to 100 consecutive calls were measured from each recording location per day of recording so the data set indicates the relative occurrence of each of the call types per base and year. There were very few ascending whistles at Casey. All of the trills and mews contained a single element. This data set was published in Bioacoustics 11: 211-222. The fields in this dataset are: Observer Station Location Time Call Number Call Type Frequency Duration Elements Overlap In 2011, another download file was added to this record, providing recording locations made during the project in 2010. Furthermore: In 1997 Daniela Simon made some opportunistic recordings for the project near Casey. The recording locations were: Berkley Island 110 38'E, 66 12' 40"S Herring Island 110 40'E, 66 25'S O'Brien Bay 110 31'E, 66 18' 30"S Eyres Bay 110 32'E, 66 29" 20"S The Davis sites: IN 1990 THERE WAS ONLY ONE RECORDING SITE - 78 12.5' E, 68 31.6' S IN 1997 RECORDINGS WERE MADE AT THE FOLLOWING SITES EAST SIDE OF WEDDELL ARM - 78 07.55' E 68 32.17' S PARTIZAN ISLAND - 78 13.66' E 68 29.57' S LONG FJORD - 78 18.95' E 68 30.24' S TOPOGRAV ISLAND - 78 12.40' E 68 29.33'S OFFSHORE - 77 58.73'E 68 26.35'S TRYNE BAY - 78 26.25'E 68 24.87'S LUCAS ISLAND - 77 57.00'E 68 30.36'S WYATT EARP ISLANDS - 78 31.51'E 68 21.31'S ================================================================================ The attached document is "a listing of the Weddell seal breeding locations near Mawson where Patrick Abgrall in 2000 and Phil Rouget in 2002 made underwater recordings". The sound recording effort in 2000 was not as high as it was in 2002, hence fewer locations are listed. The Abgrall sites are referred to in the paper 'Variation of Weddell seal underwater vocalizations over mesogeographic ranges' that Abgrall, Terhune Burton co-authored, published in Aquatic mammals in 2003. This paper also refers to the Casey and Davis sites above. The Rouget sites relate to the metadata record 'Weddell Seal underwater calling rates during the winter and spring near Mawson Station, Antarctica' Entry ID: ASAC_1132-1 In general the seals can create breathing holes in areas where tide cracks form, namely close to grounded icebergs, the shoreline and islands. I doubt that they could/would create breathing holes through solid 2 m ice.

  • Underwater recordings of vocalisations of Weddell seals were obtained at 8 locations within the Vestfold Hills (7) and Larsemann Hills (1). The recordings were made near groups of seals on the ice during the mid to late part of the breeding season. Recordings were obtained using a variety of hydrophones and both Sony Digital Audio Tape (130 during 1992 season) and standard analogue cassette (60 during 1991 season) formats. Over 11,000 vocalizations were analyzed. The calls were classified into 12 major call types (Pahl et al. 1997 Australian Journal of Zoology 45:171-187). The underwater repertoire is different than that of the seals at McMurdo Sound or the Palmer Penninsula (Thomas et al. 1988 Hydrobiologica 165:279-284). The Weddell seals at the Vestfold Hills do not exhibit the between-fjord vocal differences reported by Morrice et al. (1994 Polar Biology 14:441-446). The relative usage of each call type did not vary between the earlier and later recordings (Pahl et al. 1996 Australian Journal of Zoology 44:75-79). The recordings are currently being used to support other studies on Weddell seal vocalizations. Legend for ASAC_556.csv - csv text format. The following legend describes the 39 variables in this file. The codes for some of the variables are presented in the 1997 publication: Pahl, B.C., Terhune, J.M., and Burton, H.R. 1997. Repertoire and geographic variation in underwater vocalisations of Weddell seals (Leptonychotes weddellii, Pinnipedia: Phocidae) at the Vestfold Hills, Antarctica. Australian Journal of Zoology 45: 171-187. The fields in this dataset are: VariableSubject or code 1LOCATION; recording location; see AJZ article, Figure 1 2DATE; reference day, (date of day 1 has been lost) 3YEAR; 1 = 1991, 2 = 1992 4CASSETTE; cassette number, identifies individual recordings 5CALNO; call number, case numbers of each call, sequential 6CTYPE; call type, provisional call type, subjective initial classification (see below) 7NOELM; number of elements (discrete sounds) in the call 8EL_NO; element within that call relating to next 12 variables, for variable 8, only data from the first element is used 9WVFRM; waveform of element, see AJZ article for codes 10CLSHP; call shape, see AJZ article, Figure 2 for codes 11E_D; duration of the first element (seconds) 12IND1; duration of the interval between the end of the first element and the start of the second element (seconds) 13CALLD; total duration of the call (all elements; seconds) 14INCD; duration between sequential calls (seconds) 15O_LAP; overlap, is call overlapped by another call? 0 = no, 1 = yes 16S2STM; unknown measure 17SFREQ; frequency at start of first element (Hz) 18EFREQ; frequency at end of first element (Hz) 19HFREQ; highest frequency of first element (Hz) 20LFREQ; lowest frequency of first element (Hz) 21E_NO; element number, half way through the call. Data for the next 9 variables relate to this element, applies only to multiple element calls 22CLSHP; call shape of the middle element, same code as variable 10 23WVFRM: waveform of the middle element, same code as variable 9 24E_D; duration of the middle element (seconds) 25IND1; duration of the inter-element interval before the middle element 26IND2; duration of the inter-element interval after the middle element 27SFREQ; frequency at start of the middle element (Hz) 28EFREQ; frequency at end of middle element (Hz) 29HFREQ; highest frequency of middle element (Hz) 30LFREQ; lowest frequency of middle element (Hz) 31E_NO; element number of the last element of the call. Data for the next 8 variables relate to this element, applies only to multiple element calls 32CLSHP; call shape of the last element, same code as variable 10 33WVFRM: waveform of the last element, same code as variable 9 34E_D; duration of the last element (seconds) 35IND2; duration of the inter-element interval before the last element 36SFREQ; frequency at start of the last element (Hz) 37EFREQ; frequency at end of last element (Hz) 38HFREQ; highest frequency of last element (Hz) 39LFREQ; lowest frequency of last element (Hz) Codes for call types (variable 6). The provisional call types were amalgamated into 50 call types that were arbitrarily numbered from 201 to 250. These were subsequently classified into 13 broad categories (Pahl et al. 1997). The amalgamation of the provisional call types of variable 6 into the 50 call types presented in Pahl et al. (1997) is as follows: Call TypeProvisional Call Types (variable 6) 2011 7, 24, 36, 72, 31, 40, 73, 77, 107, 110, 31, 136 2023, 46, 54, 128, 33, 13, 140, 10, 25, 9, 139, 88, 46, 27, 126, 67, 91, 27, 126, 135 20359 204113 20514, 48, 69, 64, 49, 19, 92, 43, 75, 127, 99 206122, 124 2072, 41, 58, 93 20847, 138 20962, 132 210102 211115 21221, 23, 45, 35 21368, 80, 84 214114 2154 216118 21752, 78 2185, 6, 11 219104 22017, 22, 65, 97, 32, 26 22128 22283, 100, 101, 111, 105 22329, 30, 42, 51, 44, 94, 95 22487 22512 22682 2278 22818, 20, 57, 108 229109, 119 23034, 70, 130, 53, 121 23163 23298, 120 23389 23490 23556, 117 23671, 106 23785 238103 23974 24096 24176, 123, 133 24281, 86 24315 244112 24538 24679 24739, 127, 129, 55, 60 24816, 37, 50 249116 25066 For additional information or clarification, please contact Dr. J. Terhune, Dept. of Biology, University of New Brunswick, P.O. Box 5050, Saint John, NB, Canada E2L 4L5, terhune@unbsj.ca or +1 506 648 5633. See the link below for public details on this project.