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SCAR Bulletin No 135, October 1999

Summary Reports To XXV SCAR Concepción, Chile
27-31 July 1998

Group of Specialists on Seals

1. Introduction

Professor D B Siniff, Convenor, welcomed participants to Concepción. The SCAR Group of Specialists on Seals is charged with reviewing the status of Antarctic pinniped stocks, monitoring the number of seals killed and captured, encouraging and coordinating scientific research on Antarctic pinnipeds, and providing scientific advice and recommendations to SCAR and other international organizations associated with the Convention on the Conservation of Antarctic Seals (CCAS), the Antarctic Treaty, and the Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR).

The membership of the Group is: D B Siniff (Convenor), J L Bengtson (Secretary), M N Bester, I L Boyd, H R Burton, A W Erickson, R M Laws, Y Naito, and D Torres.

All members of the Group were present at the meeting except Drs. Boyd and Naito, who had relayed their regrets to the meeting, but were unable to attend because of scheduling conflicts.

As has been the Group's practice at its previous meetings, scientists with expertise in pinniped research were invited to participate in the meeting as observers. The participation of observers has been a valuable contribution to the Group's deliberations at past meetings, and the observers attending the current meeting were encouraged to participate fully.

2. Developments in Seal Research

Oral progress reports on developments in Antarctic pinniped research were presented by Drs. Bengtson, Bester, Bornemann, Boveng, Burton, Croxall, Plötz, Shaugnessy, Siniff, Southwell, Torres, and Vergani.

Brief summaries of progress reports are provided in Appendices 3-17 of the full report. The reports describe pinniped research being conducted by scientists in the following countries:

Argentina A R Carlini, D F Vergani
Australia H Burton, P Shaughnessy, C Southwell
Chile D Torres
Germany J Plötz/H Bornemann
South Africa M N Bester
United Kingdom I L Boyd
United States J L Bengtson/PL Boveng, D B Siniff

In keeping with its practice of promoting exchange of research results and disseminating relevant information, citations of recent literature pertaining to Antarctic pinnipeds have been appended to the full report in the references section. This list includes citations of publications and reports that had either been produced since the Group's previous compilation in 1996, or had not previously been included in the list.

3. Convention on the Conservation of Antarctic Seals

Review of Returns
The returns of Antarctic seals killed or captured by nations, as required under the Convention on the Conservation of Antarctic Seals (CCAS) and the Agreed Measures for the Conservation of Antarctic Fauna and Flora were reviewed.

The reporting requirements under CCAS specify that annually, by 30 June, each Contracting Party to the Convention is to prepare a report describing activities conducted during the previous year under 'special permits' (i.e., scientific research), and to provide these reports to other Contracting Parties and to SCAR.

In this regard, CCAS requires that information on all pinnipeds 'killed or captured' be reported annually. For the purposes of reporting under the Convention, 'killed or captured' refers only to those seals that are removed from populations, which in practice can be accomplished in one of three ways: 1) killing, 2) capture of seals to be taken into captivity, and 3) capturing seals and releasing them in a different location than the place where they were captured (i.e., removing them from their population and releasing them elsewhere).

In the event that no seals are killed or captured (either captured and removed from the Treaty Area or captured and released at a different locality within the Treaty Area) by a country in a given year, that country is required to provide other Contracting Parties and SCAR with a nil report (i.e., a report confirming that no seals were killed or captured).

It was noted that, at least in terms of the reports received over the past two years by the Group, reporting by nations continues to be incomplete. However, the Group also noted that there is no evidence that the number of Antarctic seals that have been 'killed and captured', if any, is at anything but a neglible level.

Status of Stocks
The Group reviewed recent information on the status and population trends of all species of Antarctic pinnipeds. Although the Group had prepared a 5-year update of Antarctic pinniped status and trends for CCAMLR at the Group's last meeting, these tables were again updated with available information. The next formal 5-year update of pinniped status and trends will be prepared at the Group's next meeting, in time for submission to CCAMLR's meeting in October 2000.

Antarctic fur seal (Arctocephalus gazella) populations continue to increase throughout most parts of this species' range. Fur seal abundance in the South Shetland, Macquarie, Heard, and Marion islands appears to be increasing, while the breeding population in the South Orkney Islands has been relatively stable since about 1973. Whereas the number of fur seals inhabiting the coastlines of the mainland of South Georgia continues to increase numerically and expand geographically, the number of fur seals at Bird Island seems to have stabilized or perhaps even declined slightly (presumably due to space limitations).

Populations of sub-Antarctic fur seal (A. tropicalis) are increasing rapidly, and a small population appears to have established itself at Macquarie Island together with Antarctic fur seals and New Zealand fur seals (A. forsteri).

Southern elephant seal (Mirounga leonina) populations continue to decline at Marion and Macquarie islands, but are perhaps stabilizing at Crozet and Kerguelen; the South Georgia stock appears to be stable.

No new information concerning pack ice seal densities was yet available since the Group's 1996 updating of Table 4. It was noted that the data anticipated to be forthcoming from the APIS Programme's coordinated circumpolar survey of pack ice seals will provide comprehensive information on the distribution and abundance of all four species of Antarctic pack ice seals.

4. Convention for the Conservation of Antarctic Marine Living Resources

It was noted that copies of the workshop report on APIS Survey Design and Implementation had only recently become available. CCAMLR has an interest in this report because it may provide a foundation for developing standard methods for surveying pack ice seals as part of CCAMLR's Ecosystem Monitoring Programme (CEMP). The Secretary indicated that he would send a set of these reports to the CCAMLR Secretariat in the near future so that the reports could be available for the next meeting of WG-EMM

There had apparently been some confusion over the Group's most recent submission to CCAMLR of its 5-year update on the status and trends of pinnipeds. The Secretary was asked to check with Dr Everson of WG-EMM to ensure that CCAMLR had a complete record of the most recent 5-year update and accompanying text.

5. APIS Program

The APIS Programme has been in the field since 1996, with major efforts occurring in 1997/98, 1998/99, and planned for 1999/2000. Table 1 briefly summarizes the current status of the several national programmes that have participated and other planned activities.

The following sections briefly discuss some of the APIS topics covered at the meeting. A complete discussion of the decisions reached is presented in the full report.

Survey protocols
An extensive discussion of the APIS Programme during the meeting included many details of data collection protocols that it was essential to agree so that data from the various national programmes will be comparable when analysis workshops begin. Discussions focused on standardizing such variables of concern during census operations as speed and altitude for helicopter censuses, problems associated with species identification, decisions regarding the definition of a group of seals, measurements of the probabilities of missing seals during censuses, and classification and recording of environmental conditions during census operations. The details of these discussion will be presented in the full report of the meeting

Sea ice
Since the 1996 APIS workshop on survey design, the ASPeCt Program has developed methods for collecting sea ice data along vessel transects. ASPeCt researchers have indicated through informal contacts that data collected on APIS cruises according to the ASPeCt protocols would be very useful. These methods include hourly classification of ice type, thickness, floe size, and topography. During APIS studies, aboard Australia's Aurora Australis, the methods were found to be feasible but time consuming, and required considerable training for observers.

It may not be possible, therefore, to collect the full complement of data desired by ASPeCt in APIS cruises that are too limited in personnel to devote a large fraction of one or more observers' time to collection of sea ice data. Where it is possible, however, either by including additional personnel or by including ASPeCt researchers on APIS cruises, data should be collected in a manner so as to be of mutual interest to both of these SCAR programmes.

A task group was established (Drs Bester, Boveng, and Erickson) to provide recommendations on the minimum set of variables that should be monitored and the appropriate sampling frequency for adequate characterization of sea ice. The Group was asked to continue this work and make the results available as soon as possible so that preparations could be made for surveys scheduled for the 1998/99 austral summer.

During the aerial survey portions of APIS cruises, it will not be possible to assess ice thickness (and perhaps other parameters) in the manner required by the ASPeCt protocols. Classification of ice from aerial platforms is likely to be limited to ice types, floe sizes, and percentage cover. These variables should be measured or estimated by methods that minimize the distraction of observers whose primary duties are counting and identifying of seals, and that produce data that are consistent with those collected in the shipboard portions of the surveys.

One technique that frees observers' time and allows considerable flexibility in analysis is to use downward looking (digital) video to record the ice under the path of an aerial survey platform. The imagery can be analyzed quantitatively following the survey. It was recommended that this technique be included in future APIS aerial surveys. Drs Bengtson and Plötz offered to provide advice on camera configurations that have been tested successfully on helicopters and fixed-wing aircraft.

Genetic studies
During APIS field studies, many opportunities will be presented to obtain small samples of tissue from individual seals handled, which can be used for genetic studies. Drs Curtis Strobeck and Ian Stirling, Canada, have agreed to be the depository and to carry out analyses on these samples.

Two areas of study to be examined are: 1) the patterns of genetic diversity in relation to species life history patterns, and 2) the evolutionary history of the four species of pack ice seals (Weddell, Ross, crabeater, and leopard). Microsatellite techniques will be used in these analyses and it is anticipated that samples from all areas of the Antarctic pack ice region will be obtained during the APIS studies.

Data management
The circumpolar survey will represent the joint efforts of several nations throughout the Antarctic pack-ice. It is important that these data be analysed in a consistent and unified manner. To this end, compilation of the data from each nation's survey effort into a single database is essential. Also, there is much data from earlier survey work that will provide valuable comparisons in time or space with the current circumpolar survey. Compilation of these data into the same database would greatly facilitate such temporal and spatial comparisons.

Design of such a database will not be a simple task, as earlier data will differ in form from data to be collected in the circumpolar survey, and even in the circumpolar survey, some differences in the form of data, due to differences in survey platforms, will exist. It is proposed that a workshop be held in 1999 to identify existing data sets, design a database that can accommodate both existing data sets and data from the circumpolar survey, examine means for analysis of circumpolar survey data, and consider possible re-analysis of existing data in light of recent advances in knowledge of survey issues and seal behaviour.

Liaison with other research programmes
The second international EASIZ (Ecology of the Antarctic Sea Ice Zone) cruise of the RV Polarstern in 1998 also included seal research of the APIS Programme. The joint project between scientists of several nations linked studies on the demersal and pelagic fish communities with the feeding ecology, migratory behaviour, abundance and distribution of pack ice seals in the eastern Weddell Sea. In order to gain new insights into the trophic relationships between top consumers and their prey, this venture demonstrates fruitful cooperation between scientists of different disciplines working within both the EASIZ and APIS Programmes.

6. Other Business

Antarctic pinniped tagging and marking
A report (San Diego, USA 21-31 July 1997) from the CCAMLR Working Group on Ecosystem Monitoring (WG-EMM) was discussed by Dr Torres, and he brought to the attention of the Group the decision by WG-EMM to standardize color codes of tags placed on fur seals to make the locations of tagging obvious upon resighting. This was of particular interest to the Group since it attempts to maintain an Antarctic seal tagging and marking database at the National Marine Mammal Laboratory, Seattle. The Group suggested that if the tagging database was to be kept current, information relative to tagging plans, colour, and numbering sequences needed to be forwarded to the Seattle laboratory for inclusion. Further, members of the Group were also reminded that recent tagging operations should be forwarded to the Seattle laboratory. The purpose of the tagging database is to provide information on resighting to research programmes when their own tagging records do not contain information on the tags that are sighted at their field camps.

In considering the colour codes suggested by WG-EMM, it was noted that the recommended procedure was to have the male and female portions of the individual tags separate colours. The Group felt that this recommendation might create identification problems in the future, because of color fading, as well as confusion that might arise because of seeing only one side of a tag during resighting efforts.

The Group would be willing to comment in more detail if requested.

Release of indigenous species
The Chairman of the Working Group on Biology requested the Group consider whether SCAR Recommendation XXIV-3 be allowed to stand or should be removed. This recommendation essentially urges National Committees to discontinue the practice of the rehabilitation of Antarctic species that stray to the southern continents, and if the rehabilitation is successful, seek to return the specimens to the Antarctic environment. The Group agreed that this recommendation should stand and the practice be discouraged for the reasons indicated in the original resolution.

Plastics in the Antarctic marine environment
The existence of small particles of plastic in seal faeces (scats) suggests that bioaccumulation of such particles may be taking place in Antarctic marine ecosystems. The route(s) such particles might travel through the ecosystem could involve several trophic levels and species groups. Monitoring these particles for abundance, distribution, and species involved would seem to be a very important research effort and the Group encourages SCAR Groups to discuss this issue and to encourage members to develop plans to monitor such occurrences.

The distribution and abundance of marine debris, which is principally composed of plastics, in the Southern Ocean has been studied both by monitoring beach debris at selected sites such as certain west-facing beaches of sub-antarctic islands and by towing neuston (surface) nets behind ships. Both these techniques have severe limitations. Beach debris surveys are size selective as small plastic pieces are more difficult to see and quantification is related to substrate as dark fine sand better highlights small light-coloured plastic than do pale pebbles and cobbles. There is also the problem that debris on a beach at any time is the resultant of the interplay of the rates of debris accumulation, removal and destruction. These are not constant as they are very much weather dependant. Plastic arrives and is carried above high-tide lines with certain currents and wind speeds and is removed in other conditions. Thus the beach debris documented on any date is directly related to the weather conditions of the few days previous to the survey.

At sea, debris assessments are bedevilled by the very low concentrations of plastic on the southern ocean surface. The few neuston tows taken in the Southern Ocean have generally failed to collect any plastic at all; and so this direct sampling technique is an unsuitable approach to monitoring year-to-year variation of the sea-surface burden of floating plastic. However another method of monitoring plastics composition and abundance is to take advantage of the biological concentration of these sea-surface materials. Due to their densities being almost always less than 1, plastic fragments are held on the surface of the sea which is a zone of intensive foraging effort by a variety of organisms including fish and birds. Plastic materials within certain size ranges (usually 1 to ~10 mm) are taken by foraging error. At the top of the food web are large mammals such as seals and recent collections of faecal samples from sub-antarctic fur-seals show that in some sites at least plastic pieces are relatively common. There is, therefore, great scope for collaborative research between SCAR countries to sample widely throughout the Southern Ocean to establish the commonality of the processes described above and to elucidate more precisely the routes and fluxes of plastics concentration between species in different areas. It might be expected, for example, that as the relative abundance of various species of surface-feeding fish change so too will the availability of plastics to seals also change. The number of faecal samples necessary to be collected for useful information to be extracted from them is large. Sample sizes of 100+ are recommended.

7. Membership and Future Priorities

Professor Siniff expressed his desire to step down as Convenor of the Group. The Group expressed its sincere thanks to Professor Siniff for his dedicated service to the Group over the past 25 years, as co-Convenor from 1973-1988, and as Convenor for the past ten years.

Drs Erickson, Laws, Naito, and Siniff would cease to be members of the Group.

The Group thanked them for their dedicated service to the Group over the years, and expressed their regrets that the Group would no longer have the benefit of the leadership and depth of experience in Antarctic pinniped research represented by these scientists. Much of the success that the Group has enjoyed over the past 26 years was due in large measure to the insight, wisdom, and energy generously provided by Drs. Erickson, Laws, Naito, and Siniff. The Group was encouraged, however, that each of the four members stepping down as a full member of the Group had indicated their wish to continue as associate members of the Group.

The Group was originally formed to provide expert advice in support of the Convention on the Conservation of Antarctic Seals (CCAS). Since its formation in 1973, as the first SCAR Group of Specialists, it has been a central source of information and advice about the status, conservation, and management of Antarctic seals to other international organizations; including CCAMLR and IUCN. In addition, it published the book 'Antarctic Seals: Research Methods and Techniques' (Laws, 1993; Cambridge University Press) and was responsible for planning, coordinating, and implementing the APIS Programme. It has collated information about population sizes and trends, seal harvesting, and research activities, was involved in some of the early developments in satellite tracking methods for marine mammals, and continues in this interest.

Review of Membership
Despite these valuable activities, the Group agreed that it was timely to consider:

Updating the membership of the group on the retirement of four members, to include new and younger participants,

Examining the size of the Group with a view to reducing the number of full members while maintaining effectiveness, and

Creating an efficient core group of active members, representative of the full range of research currently being undertaken on Antarctic seals. The key areas of interest in terms of species are: 1) fur seals, 2) elephant seals, and 3) pack ice seals, and in terms of scientific disciplines: 1) ecology and behaviour, 2) population dynamics, 3) physiology, 4) survey design and methodology, and 5) electronic technology.

The current membership of the Group is nine. It is proposed that the number of core members should be seven, comprising:

J L Bengtson, Convenor (ecology, diving behaviour, technology, ice seals, fur seals)
I L Boyd, Secretary (behavioural ecology, population dynamics, energetics, fur seals, ice seals)
M N Bester (census, ecology, ice seals, elephant seals)
A S Blix (diving physiology, pack ice seals)
H Burton (food habits, contaminants, Weddell seals, elephant seals)
J Plötz (behaviour, energetics, pack ice seals)
D Torres (population ecology, fur seals)

All these individuals have active interests in Antarctic seals and are leading scientists within their national Antarctic research programmes. They represent a broad range of expertise and influence, and have an appropriate balance of experience of the operation of the Group of Specialists on Seals in the past, new blood and wider participation in the activities of SCAR. They also bring wide geographic representation from Europe, North and South America, Australasia, and Africa.

In addition, there should be financial provision to invite at least one individual with specific essential expertise to particular meetings. Specifically, the Group wishes to co-opt Dr Colin Southwell, Australia, for two years to continue to guide it on APIS Programme survey design and protocols and on population assessment.

This composition means a basic group of eight.

In addition, a comprehensive system of Associate Membership should be developed to provide formal support for other scientists working on seals (or on disciplines relevant to the Group's tasks), to help them to obtain funds from their national sources to support their attendance at meetings.

The Group proposes Dr Bengtson as new Convenor. Dr Bengtson has been a member of the Group for the past 15 years, serving as its Rapporteur from 1983-1986, and as Secretary for the past twelve years. In addition, he has served as Chairman of the APIS Programme Steering Committee since its inception in 1994.

Dr Boyd is proposed as the Group's new Secretary. He has been a member of the Group since 1994, and has served as Secretary of the APIS Programme for the past four years.

8. Next Meeting

The Group agreed that it would be worthwhile to hold an APIS data management workshop sometime in mid-1999 (April-July). It was agreed that SCAR should be asked to provide US$10,000 to enable members to attend this meeting.

It was agreed that it will be necessary for a full meeting of the Group to be held in approximately two years time. The Group recommended that its meeting should be scheduled to precede the meeting of XXVI SCAR, to be held in Japan in 2000. It was agreed that SCAR should be asked to provide US$12,000 to enable members to attend this meeting.

9. Recommendations

Membership: The membership of the SCAR Group of Specialists on Seals should be revised as follows:

Dr A W Erickson, U.S.A; Dr R M Laws, UK; Dr Y Naito, Japan; and Professor D B Siniff, USA to retire as members,
Professor A S. Blix, Norway; and Dr J Plötz, Germany to become full members,
Dr C J Southwell, Australia, to be added to the Group's membership for two years during the APIS Programme,
due to his special expertise in survey design, and Dr J L Bengtson, USA; and Dr I L Boyd, UK be designated as the Group's
new Convenor and Secretary, respectively.

With the proposed reduction in the Group's size, it is also recommended that a designation of 'Associate Member' could be conferred on additional scientists who can facilitate the Group's work through their expertise in pinniped science or through other relevant disciplines.

APIS Data Workshop: A workshop should be held in 1999 (e.g., April-July) to evaluate requirements and possible mechanisms for combining and jointly analyzing relevant data collected within the APIS Programme's circumpolar surveys (e.g., aerial and ship survey sightings, survey conditions, sector coverage, sea ice observations, remote sensing imagery of sea ice concentrations). SCAR is requested to provide financial support to assist participants with their travel expenses.

Next Meeting of the Group of Speceialists on Seals: The Group of Specialists on Seals should hold its next full meeting in 2000 prior to the meeting of XXVI SCAR. SCAR is requested to provide financial support to assist participants with their travel expenses.

Reintroduction of Indigenous Species: SCAR Recommendation XXIV-3, which discourages the practice of returning rehabilitated wildlife to the Antarctic environment, should stand for the reasons indicated in the original resolution.

10. Closing of the Meeting

The report of the meeting was reviewed and adopted by the Group. Copies of the final report were to be distributed to participants and other Antarctic pinniped researchers following the meeting.

It was agreed that the SCAR Secretariat would be asked to publish and distribute the report, including its appendices, as part of the SCAR Report series.

In closing the meeting, the Convenor thanked all participants for their assistance in the effective running of the meeting.

The meeting was adjourned.

Acronyms

APIS Antarctic Pack Ice Seals Programme
CCAS Convention for the Conservation of Antarctic Seals
CCAMLR Convention for the Conservation of Marine Living Resources
CEMP CCAMLR Ecosystem Monitoring Programme
WG-EMM Working Group on Ecosystem Monitoring (CCAMLR)
ASPeCt Antarctic Sea-Ice Processes, Ecosystems and Climate (GLOCHANT)
EASIZ Ecology of the Antarctic Sea Ice Zone
IUCN International Union for the Conservation of Nature

Scientific Committee on Antarctic Research

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