UNIVERSITY OF TASMANIA
SCHOOL OF GEOGRAPHY AND ENVIRONMENTAL STUDIES
2006 FRIDAY FORUM SERIES – THE THING ABOUT ISLANDS
Environmental Planning and Management of Australia’s
Sub-Antarctic Macquarie and Heard Islands
Dr Lorne Kriwoken
29th September 2006. Geology/Geography Lecture Theatre,
Earl Street Entrance, Sandy Bay Campus, 4 pm
Macquarie Island (MI) and Heard Island and McDonald Islands (HIMI) are spectacular and
remote Australian sub-Antarctic islands located in the Southern Ocean. MI is 1,500 km
SSE of Hobart (54030’S, 158055’E) and half way between Tasmania and Antarctica. Steep
rocky beaches rise sharply to an undulating glacier-free plateau roughly 100-300 m above
sea level, with Mt Hamilton the highest point at 433 m. MI is 34 km long, up to 5 km wide
with an area of 12,785 ha. Heard Island (36,800 ha) and McDonald Islands (360 ha) are
4,100 km SSW of Perth (53005’S, 73030’E) and about 1,700 km north of Antarctica. The
most prominent feature on Heard Island is Australia’s tallest mountain and only active
volcano, Big Ben, rising to 2,750 m. Recent volcanic activity has in fact doubled the size of
the McDonald Islands.
Both islands lie in the path of the ‘Furious Fifties’, the winds that circle the high southern
latitudes. The Southern Ocean at these high latitudes is characterised by very rough seas,
cold mists, sea-fogs and strong average wind speeds. MI lies just north, and HIMI just
south, of the Antarctic Convergence where cold Antarctic waters mix with relatively
warmer northern water. These extreme sub-Antarctic environmental conditions, and the
location of the islands above and below the Antarctic convergence, are key factors
influencing the flora and fauna. The harsh climate and geographical remoteness have
largely prevented permanent settlement at both locations.
HIMI and MI are home to an abundant and diverse array of unique sub-Antarctic wildlife.
The vastness of the Southern Ocean and the isolation of limited landmass mean that MI
and HIMI provide crucial habitat for birds, seals and sub-Antarctic vegetation. On MI and
HIMI 3.5 and 1.3 million seabirds annually breed and moult, largely represented by five
penguin species. 850,000 pairs of endemic Royal penguins are found on MI and 1 million
pair of Macaroni penguins on Heard. Endemic cormorant species are found on both MI
and HIMI. Of particular importance is the breeding habitat for threatened migratory
species, such as the Wandering albatross, with less than 20 breeding pairs known for MI
and only one for Heard Island. Seals represent the other major vertebrate on MI and HIMI,
and include Antarctic, sub-Antarctic fur seals, and Southern elephant seals on HIMI, plus
New Zealand fur seals on MI. One seventh of the world's population of elephant seals
(80,000) are found on MI (PWS 2003). In addition to wildlife, HIMI and MI provide remote
outposts for a specialised suite of vegetation, notably on Heard Island, which has been
affected by the dramatic glacial retreat of 70 to 80 per cent over the past 50 years. The
cold, windy environment means slow growth and low profiles, with no trees and the tallest
species are slow growing mega-herbs, and three endemic vascular species on MI. Plant
communities include cushion beds, herbfields and tussock grasslands.
The aim of this presentation is to compare and contrast MI and HIMI and provide an
analysis of the most important and emerging issues over the next decade. The
presentation begins with a brief outline of early discovery, industry and science. This is
followed by an overview of legislative, institutional and management arrangements, with
particular attention made to World Heritage status. Emerging issues are then presented.
The management, scale and impact of human activities are introduced focusing on both
science activities and commercial tourism. This is followed by an assessment of relevant
issues associated with quarantine, disease and alien introductions. Commercial fishing
pressure is examined along with problems of enforcement. The presentation concludes
with a comparative analysis of emergent issues for both Australian sub-Antarctic islands.
Dr Lorne Kriwoken is a Senior Lecturer in the School of Geography and Environmental
Studies and a Research Associate with the Antarctic Climate and Ecosystems CRC. He
teaches units in natural environment and wilderness management, environmental impact
assessment and environmental technology. His research interests include environmental
planning and management, oceans policy and law, protected areas, sustainable polar
tourism and environmental impact assessment.