1992 Wintering Field Season at Heard Island.

Taken from the report:

Genesis of the Expedition

The concept of the 1992 expedition arose from the need to gain access to animals at Heard Island for research at precise times of the year to deploy and retrieve time-depth recorders. An Antarctic Science Advisory Committee workshop on the Southern Ocean Ecosystem was held on 10-11 September 1989 to discuss future plans for ANARE areas of operation. The workshop was attended by myself (KG - Ken Green) and Harry Burton (HRB) for the Land-based Biology section. It became apparent that the two consecutive summers needed to deploy and retrieve the recorders (one leaving Heard Island in the autumn, the next arriving early in the spring) could not be accommodated in the planning process because of planned commitments in the eastern sector of the Australian Antarctic Territory. The suggestion was therefore made by us that if two summers were impossible then perhaps the best solution was a wintering party. A memo to this effect was drafted by us and submitted on 26 September 1989. This was considered at a Heard Island Committee meeting on 18 October 1989 when changes to the shipping program were suggested that would allow two consecutive summers on Heard Island and it was concluded that "this arrangement should.....negate the need for a wintering program in the near future".

The suggested rearrangement did not fully match the times required and the Land-based Biology section was loathe to deploy equipment in one summer without guaranteed access to the animals in the following spring. It was felt that this could only be assured if the biologists were on the island through the whole period. An additional advantage was that dietary studies of the main fish predators could be continued throughout the winter period. To this effect the proposal for a wintering party was re-submitted on 26 February 1990 with the suggested personnel being three biologists and three people in support. The proposal was re-submitted in more detail on 4 May 1990 and was examined by the ANARE Annual Planning Committee who referred it to the Assistant Director (Science) to "examine the options for conduct of this program and that following this the Heard Island Planning Committee and to the Assistant Director (Science) who was requested to prepare a paper for distribution to committee members for consideration at a meeting to be held on 17 July 1990.

At this point the maiden voyage of the Aurora Australis took place with one aim being to deploy a party of four on Heard Island for a period of one month to undertake research into seals and penguins. This party included two of the subsequent wintering party (see Green 1990). This expedition returned in time for the Heard Island Planning Committee meeting which was held to hear reports on the 1990 expedition and to consider the proposals for 1993. A reduced complement of four expeditioners was suggested in a proposal appearing under the signature of the acting Assistant Director (Science). The committee voted to forward the proposal to the ANARE Annual Planning Committee on 26 July 1990 with the suggested alteration in timing so that the wintering expedition occurred in 1992 rather than 1993 to avoid clashing with science requirements for the Lambert Traverse.

The ANARE Annual Planning Committee referred the matter to the executive and on 27 August 1990 the Heard Island Planning Committee agreed to "support a limited winter program on Heard Island in 1992 on the condition that it is to be a purely land-based exercise with work restricted to the Spit Bay area" with "a final decision on the conduct of a Heard Island wintering program (to) be made by the Executive in the near future.". Approval was given at the Heard Island Committee meeting of 24 September 1990, subject to approval by the Antarctic Research Evaluation Group (AREG) of the major programs suggested by the Land-based Biology section. At the Heard Island Planning Committee meeting of 12 December 1990 it was confirmed that AREG had provisionally approved the Land-based Biology programs and that the Executive "have supported the program subject to ASAC endorsement of the three proposals put forward."

At this stage the Heard Island expedition was expected to proceed on that basis with additional programs to be considered by AREG. From this point the expedition had sufficient momentum to keep going and subsequent meetings of the Heard Island Committee dealt mainly with questions of logistics, infrastructure and procedures (these are covered in Antarctic Division file number 89/754). The final composition of the personnel for the party was not settled until 14 October 1991. The expedition sailed from Hobart on 8 January 1992 on board the Aurora Australis.

Assessments of the possibility of landing by zodiac at Spit Bay were made on 24 and 28 January and on 28 January the party was deployed at Atlas Cove using three inflatable rubber boats. For a narrative of the expedition see the Log (later in the report).

Scientific Background

A commercial Soviet fishery has existed in the Iles Kerguelen region from the early 1970s and catches averaged about 20,000 tonnes per year between 1979 and 1986, dropping to 7886 tonnes in 1987 and 773 tonnes in 1988. Before 1978, the benthic species Notothenia rossi and N. squamifrons were mainstay of this fishery. The icefish, Champsocephalus gunnari increased in importance after that to constitute the majority of the catch. There has been little commercial fishing around Heard Island, and none since a 200 nautical mile Australian Fishing Zone (AFZ) was declared in 1979 (Williams and Ensor 1988). Catches of icefish by the Soviet research vessel RV Professor Mesyatsev on banks to the north-east of Heard Island indicated concentrations of this species in commercial interest, but other species, including benthic fishes also occurring in the diet of the seals, are not sufficiently abundant for commercial interest at this time (Williams and Ensor 1988). Results from the 1987/88 Heard Island ANARE suggested that there was a potential for competition between the increasing numbers of Antarctic Fur Seals and any future commercial fishery (Green et al 1990). Winter data were, however, lacking. In 1990 the first ANARE expedition to be present on the island into the winter period since the 1954 wintering expedition took place, with the main program being an attempt to examine the winter diet and feeding areas of Antarctic Fur Seals. Subsequent assessment of the diet of Southern Elephant Seals comparing Macquarie and Heard Islands (Green and Burton in press) also showed this species to be a potential competitor, both with Antarctic Fur Seals and with a potential fishery.

Bearing in mind the possibility that a request for commercial fishing rights within the Heard Island AFZ might be made in the foreseeable future, probably as an adjunct to the Kerguelen or Antarctic fishery rather than a new venture, a full assessment of the role of fish predators was indicated. The analysis of a potential interaction between wildlife and fisheries depends on the collection of three primary sets of data: the availability of commercial fish species, the diet of the predator, and the spatial overlap in the demands of the two competing interests. The aim of the 1992 ANARE was therefore to collect all of these data. The Marine Science cruises to the area collected data on fish location and relative abundance, continuing the work of previous voyages such as Professor Mesyatsev and the Aurora Australis on its maiden voyage. The work of the shore party would be to investigate the diet of fish predators through scat collections and examination of stomach contents. The main objectives of the 1992 ANARE program on Heard Island were therefore to collect data on the feeding ecology of the major warm-blooded predators of fish in the Heard Island region (excluding whales), to provide baseline data in their ecology in the absence of a nearby fishery, and to provide an estimate of the degree of interaction between these animals and a potential fishery. This was considered to be a major scientific program, both in resources and time and was expected to net valuable scientific information from a very small deployment of personnel. In addition to the main objectives, a number of additional research programs were to be conducted by the wintering party including meteorological observations, glaciology, coastal erosion surveys and marine debris surveys.

Field Party

Erwin Erb, Medical Officer

Ken Green, Biologist

Geoffrey Moore, Biologist

David Slip, Biologist

Attila Vrana, Engineer