Internal resolution of the issue of sovereignty in a minerals regime has no legal effect upon the rights and interests of the international community. Diplomats, scientists and government officials are now more ready to concede that some form of external accommodation must be made. Assertions of common heritage over Antarctic resources cannot be ignored, if only because of the power of the United Nations (UN) to develop a rival regime creating international discord and rendering unworkable any regime adopted by the Consultative Parties.

The notion that the United Nations should have some role in Antarctica is of long standing. Proposals for United Nations involvement were made after the Second World War and again by India in 1956. It was not, however, until September 1982 that the Malaysian Prime Minister, Dr Mahathir, raised the issue in a speech at the United Nations General Assembly in which he called for a meeting to ‘define the problem of these uninhabited lands’. He alleged that the Antarctic Treaty was a neocolonial document which ‘does not reflect the true feelings of the members of the United Nations’. He suggested further that all claimants to Antarctic territorial sovereignty ‘must give up their claims so that either the United Nations can administer these lands or the present occupants act as trustees for the nations of the world’.

In the following year, Malaysia successfully argued for Antarctica to be included on the agenda for the General Assembly. After debate, a resolution was adopted calling upon the Secretary-General to conduct a comprehensive, factual and objective study on Antarctica and to report back in 1984.

The big picture

Recently at the South Pole a group of scientists, diplomats, academics, international lawyers, journalists and environmentalists had the opportunity to view a graph of the increase in carbon dioxide levels during the past 20 years – over 25%, in a straight line. The data on which that graph is based underpins the so-called greenhouse effect theory.

This chapter is founded on the belief that it is important to keep Antarctica in perspective, against the backdrop of other developments in the world community, when determining policies for its future. For example, if scientists such as those responsible for a 1984 study by the US National Academy of Science are right about the implications of a continued build-up of carbon dioxide levels and the theory of the greenhouse effect, temperatures on earth will rise by 2 or 3 deg C during the next 75 years. That could cause the west Antarctic ice sheet to melt, raising the ocean levels by a significant – even radical – degree. What energy policy would it be prudent for world leaders to follow?

If those scientists who are concerned about the phenomenon of acid rain are correct that it will continue to bankrupt various components of the global ecosphere, and that its primary cause is the increased burning of fossil fuels in vehicles, power plants and smelters, the question arises as to the conservative approach which the world community should take concerning continued reliance on such energy sources.

Antarctica is the coldest, windiest and most inhospitable continent in the world, which differs from the Arctic in being a land-based continent and in having no indigenous population. Dr Phillip Law describes Antarctic activities as occurring during four periods: the trading, imperialist, scientific and resource eras ((1985) 10 (4) Interdisciplinary Science Review, 336–8). International interest in Antarctica began with commercial whaling and sealing expeditions through the eighteenth and nineteenth centuries. This trading era was followed by an imperialist era from 1890 to the 1940s which was a period of high adventure, heroism and colonial territorial aggrandisement, though predominately of a marine nature. Expeditions during this period were amateur and were engaged in preliminary scientific work collecting, describing and classifying information. It was not until the International Geophysical Year (IGY) of 1957–8 that scientific interests were generated in earnest. During the IGY, 50 stations were set up over the Antarctic continent and comprehensive scientific work was undertaken. Research during the IGY was subsequently maintained through a permanent committee of the International Council of Scientific Unions (ICSU), the Special Committee on Antarctic Research (SCAR). One of the dominating forces for the negotiation of the Antarctic Treaty in 1959 was to ensure that territorial claims should not retard comprehensive scientific research. With this objective, the Parties agreed that:

It was further agreed that all information regarding scientific programmes in Antarctica should be exchanged, that scientific personnel should be exchanged between expeditions and stations and that scientific observa-tions and results should be exchanged and made freely available.

Antarctica, known to most people as an ice blue and beautiful but isolated and fragile continent, has long been of interest to scientists, explorers and a handful of diplomats. Its history is redolent with dramatic images of courage and comradeship, tragedy and triumph. The exploitation of marine living resources, and more recently mineral and oil resources have, however, been the dominant forces behind international interest in Antarctica. Enticed by Cook's voyages, seal hunters explored the South Antarctic islands in the late eighteenth century. Over-exploitation of seal herds lead others in the 1830s to move closer to the Antarctic continent for elephant seals and whales. Today, the depletion of fish stocks and the expansion of coastal state sovereignty over 200 mile Exclusive Economic Zones has again focussed attention upon the southern oceans, this time to harvest krill. Extravagant hopes for mineral and oil wealth, inflamed by negotiations for an Antarctic minerals regime, have directed international attention to Antarctic non-living resources, thereby prompting fears for the conservation of this fragile and beautiful continent.

It was at a time when commercial interests in Antarctica had declined, and when individual scientific research was highly esteemed, that 12 states were able to negotiate the Antarctic Treaty in 1959. Compelled by the need to avert tension and disorder and by a determination that scientific research should continue unimpeded, these states successfully avoided the formidable legal issue of sovereignty and created the Antarctic Treaty regime of interlinked conventions and recommendations. This regime is justifiably hailed as a remarkably effective international system which has largely achieved its relatively modest objectives. Times, however, have changed.

The Treaty system as an alternative to sovereignty and universality

The current debate about the various alternatives for the regulation of activities in Antarctica is not at all new. Ever since international law became interested in questions posed by polar exploration, with particular reference to the issue of resource exploitation – an interest that was already evident by the beginning of the century – the various alternatives conceivable in legal and political terms were brought into play. Two basic proposals dominated the debate. The first purported to apply the traditional modalities of the organization of the modern state to Antarctica, extending the concept of sovereignty, with the necessary variations imposed by geography, climate and distance, to the polar regions. The second dominant approach sought to negate such a possibility and to introduce, instead, forms of international organization that were generally of a global nature and on a world-wide scale.

The approach relying on sovereignty alone proved not to be a viable alternative for the regulation of the activities of man in Antarctica. The reason for this was not strictly of a legal nature, and it was certainly entirely unrelated to the question of recognition or validity in international law. Rather it was one of political realities. Conflict and confrontation were constant features of the struggle between national sovereignties competing to become established, and such characteristics could not be the basis on which to found an effective Antarctic regime. On the other hand, this approach did not properly take into account other relevant interests which were present in Antarctica, thereby also affecting the viability of this alternative.

The subject I have been asked to discuss is commercial prospects for Antarctic minerals and a succinct summary of what follows could well be ‘virtually nil’.

Another contributor, Arthur Watts, has made the point, which I repeat, that minerals occur in widely scattered outcrops in Antarctica. It is important to set this fact in the context that first, more than 95% of the continent is ice and secondly, that there is a world of difference between an occurrence and a deposit. Mapping the occurrences may indicate the existence of a deposit of sufficient size to warrant detailed investigation (for example, by drilling), with a view to possible commercial exploitation.

Let us look at what minerals are known to exist in Antarctica. In summary, from what is presently known of the exposed area in Antarctica, only coal and iron in the Prince Charles Mountains, and coal in the Transantarctic Mountains might be mined if they were located on an inhabited continent. There are a lot of other known or suspected minerals. You have heard mention, for example, of the mineral potential of the Jurassic Dufek intrusion which is a layered deposit with a structure and composition which some geologists believe to be analogous to the South African Bushveld complex. In the absence of any detailed information, it is legitimate to work on the hypothesis that such complexes could, given the circumstances of their geological origin and physical properties, contain cobalt, chromium, nickel, uranium, copper and magnetite. Without a full-scale exploration programme we are left with a pattern of association (or assumption!) based upon the geological setting. This leaves the basic questions unanswered.

Since the 1970s the Consultative Parties have been concerned to regulate and to minimise man's impact on the Antarctic environment. At the Ninth Consultative Meeting the Parties formally recognised ‘their prime responsibilities for the protection of the Antarctic environment from all forms of human interference’. They have since recommended a Code of Conduct for Antarctic expeditions and station activities, established a meeting of experts to study the effects of oil pollution on the Antarctic environment, adopted a Statement of Accepted Principles and Good Conduct Guide for Tourist Groups and recommended that environmental impact studies be made to evaluate major operations proposed in the Antarctic Treaty area. These measures are hortatory not mandatory, and they depend for their effect upon implementation by those states which choose to accept them.

In 1980 the Consultative Parties negotiated the Convention for the Conservation of Antarctic Marine Living Resources. This Convention is remarkable in many respects. Firstly it was negotiated, ratified and came into force with great speed; a speed which was fuelled by the urgent need to establish some form of regulation for the harvesting of krill and other Antarctic fisheries. The Convention is notable, secondly, for its adoption of a single ecosystem approach to conservation in which the Antarctic Convergence provides the outer limits of jurisdiction. Thirdly, and for the first time within the Antarctic Treaty system, a permanent structure was established by the Convention to give effect to its aims and objectives.

Introduction

The amount of food eaten by a population of large mammalian herbivores affects their survival, reproductive success and, in the case of domestic stock, their economic performance. But intake by the herbivores also represents offtake from the pasture. Herbivores, by harvesting plant material from the pasture, have a feedback effect on biomass, growth and species composition of the pasture. Hence the herbivore and its rangelands pasture form an interactive relationship.

This chapter summarises the available information linking food intake of the major mammalian herbivores of the Australian sheep rangelands with food availability and identifies the factors, other than food availability, that modify intake. It then discusses the major feedback effects of this offtake on the vegetation.

The relationship between the food intake of a herbivore and vegetation biomass is known as the functional response. It can take a number of theoretical forms (Noy-Meir, 1975) but is most commonly expressed as an asymptoting function, often as a monotonically increasing curve (e.g. Allden & Whittaker, 1970; Arnold, 1975). At low biomasses the food intake of the herbivore is depressed because of the difficulties in locating and harvesting food. At high biomasses the intake of the herbivore is satiated and hence intake is relatively constant over a wide range of biomasses.

Context and questions

In this book we examine the sheep rangelands of Australia, not as they were but as they are today. We focus particularly on the chenopod shrublands, a plant association that covers 5–10% of the arid and semi-arid areas of Australia (Goodall, 1979) and which occurs mainly in the winter rainfall zone (150–500 mm per year) of southern Australia (Oxley, 1979).

Our main region of study is the Menindee District (Fig. 1.1) of western New South Wales. Within this we studied two areas, the first being Kinchega National Park (440 km2). Here we examined the structure and dynamics of a grazing system comprising a vegetation dominated by perennial chenopods and annual grasses and forbs, grazed and browsed by a suite of herbivores dominated by the red kangaroo and the western grey kangaroo. The second study area is Tandou sheep station (810 km2, of which we measured the vegetation on 200 km2 and the kangaroos on about 400 km2) which abuts Kinchega to the south. There we studied much the same system as on Kinchega, but with sheep added to it.

Rainfall averages 236 mm per year but varies prodigiously between years (see Chapters 2 and 3). The weather is the driving variable of this arid-zone system, largely determining the biomass of the pasture layer month by month (see Chapter 4) and through its influence on that layer determining what the herbivores eat at any given time (see Chapter 5), how much they eat (see Chapter 6), and how far they have to move to get it (see Chapter 7).

Introduction

The sheep rangelands, a subset of the arid and semi-arid lands of Australia, form a broad semi-circular arc from northern Queensland, through New South Wales, South Australia and the southern two-thirds of Western Australia (Fig. 1.5). It covers approximately 1.7 million km2 or 22% of the area of Australia. Climate determines the outer margin of the zone in the southern half of the continent: being the amount and incidence of rain sufficient to cultivate crops, particularly wheat. In southern New South Wales, South Australia and Western Australia this approximates the 260–290 mm isohyet. In southern Queensland the sheep rangelands extend into country receiving nearly 600 mm of rain per annum. The inner margin, where the sheep pastoral zone abuts either cattle rangelands or desert, is at about the 150 mm isohyet in the south and the 300 mm isohyet in the north.

This chapter examines the climate, soils, vegetation and fauna of the sheep rangelands of Australia, focusing on Kinchega National Park and a neighbouring sheep station, Tandou. These are located near the town of Menindee (elevation 61m) at approximately 32 degrees S and 142 degrees E in western New South Wales on the floodplain of the Darling River. Almost all data in succeeding chapters were collected on Kinchega and Tandou. Both were formerly part of a much larger pastoral lease and have been grazed by sheep since 1860. In 1967 Kinchega was declared a national park under the control of the New South Wales National Parks and Wildlife Service.

The research project that forms the basis of this book was commenced within the New South Wales National Parks and Wildlife Service in 1977. It was designed primarily to examine the relationship between high kangaroo densities and vegetation in an arid-zone national park (Kinchega National Park). By examining kangaroo dynamics in relation to weather and pasture availability, and studying kangaroo movement, diet, and techniques for monitoring population change and well-being, it was also hoped to provide information relevant to management of kangaroos on rangelands. Most of the research on the Park was duplicated on the adjoining grazing lease (Tandou).

The years 1977 to 1980 saw the development of techniques for handling the peculiarities of rangeland vegetation, weather and herbivores. In late 1979 CSIRO Division of Wildlife Research (now the CSIRO Division of Wildlife and Rangelands Research) was invited to participate. The invitation was accepted and a formal agreement was drawn up in August 1980 to conduct a joint project for five years. The project was then modified and expanded, proceeding to the end of the contract period in November 1985. This book deals largely with the period of the joint study.

Introduction

This chapter explores the following questions about vegetation in the sheep rangelands:

1. (1) How does rainfall affect plant biomass?

2. (2) How do rainfall and plant biomass affect plant growth?

3. (3) How does soil texture affect plant biomass?

4. (4) How does grazing by kangaroos and sheep affect plant biomass?

5. (5) Do any of these factors dominate to explain trends in plant biomass and species composition?

These questions will be addressed using data derived from Kinchega and Tandou. Pasture and shrubs are dealt with separately. Pasture includes all vascular plants in the herbaceous layer including chenopod sub-shrubs. Shrubs occupy the mid-layer of the vegetation and comprise perennial, deep-rooted, long-lived species relatively resistant to drought. The major shrub species is black bluebush (Maireana pyramidata), a 1.5 m high chenopod shrub not very palatable to kangaroos and sheep but eaten in times of severe food shortage.

Research methods

Pasture measurements

Pasture biomass and species composition were measured and species phenology was recorded at 213 sites on Kinchega National Park and at 100 sites on Tandou for each quarter between August 1980 and February 1984. Sites were located 1 km apart on parallel east-west lines separated by 2 km.

On each sampling occasion the pasture was measured at each site on three 0.25 m2 circular plots positioned at random within the site. These plots were then caged to exclude grazing by kangaroos, sheep and rabbits and were remeasured three months later.