WEST KIMBERLEY PLACE REPORT - Department of Sustainability ...

A NATURAL AND CULTURAL REFUGE
For the people who live here, whether Traditional Owners or more recent arrivals, the
west Kimberley is home; for scientists, it is largely a tantalising unknown. The
Kimberley is vast and remote from southern centres. Travel is difficult during the wet
season, and many parts cannot be reached by ordinary means of transport at any time
of year. Along the coast, there are saltwater crocodiles and massive, powerful tides.
The west Kimberley coast, particularly at King Sound and Roebuck Bay, has the
greatest tidal range of any coastal area in Australia, and one of the greatest in the
world. Spring tides can reach up to 12 metres, and there are two tidal cycles each day.
The west Kimberley is also remarkable for having the most convoluted coastline in
Australia: it is comprised of an enormous number of islands, bays, coves and inlets,
which appear as an impossible tangle of lines on a map.
While most of the region has not yet been studied in detail, what survey work has
taken place indicates that the Kimberley is home to a highly diverse range of plants
and animals, and includes many species that live nowhere else (endemics), as well as
species that are under threat or have now disappeared elsewhere in Australia. Some of
the factors that make the Kimberley most challenging to study also make it a refuge –
providing greater resilience from introduced species and human actions, from
seasonal scarcity, and from longer term changes in climate – allowing unique
communities of species to thrive.
Kimberley country ranges from coastal mangroves and eucalypt woodlands, through
rugged ranges, flat-topped mesas and deep gorges, to rich pockets of rainforest and
savanna grasslands. Rainfall, geology, topography, soil types, and associated plants
and animals all vary significantly between the coast and inland, and from north to
south. For descriptive purposes, the west Kimberley mainland is divided into four
regions, reflecting changes in rainfall and geology: the north Kimberley, including the
Mitchell Plateau and the northern and north-western coastline; Yampi Peninsula;
central Kimberley, which includes the King Leopold, Napier, Oscar, Pillara and
Emmanuel ranges; and the south-west, made up of Dampier Peninsula and the
catchment of the Fitzroy River. The multitude of islands and reefs and other
outstanding marine features which lie off the coast are also described.
North Kimberley
The north Kimberley is an extensive area of rugged tablelands and distinctive flattopped
mesas stretching from Cape Londonderry in the north to Harding Range in the
south, and includes the Carson Escarpment, Mitchell Plateau (Ngauwudu to its
Wanjina–Wunggurr Traditional Owners) and Gardner Plateau. This is the wettest part
of the Kimberley: between 1,100 and 1,500 millimetres of rain falls on average each
year, mostly in the summer months. The area has high biodiversity values, including
the richest mammal populations in the west Kimberley, and is home to many endemic
species. The greatest diversity of plant and animal species in the Kimberley is found
in the coastal strip from the Mitchell Plateau north-east to Drysdale River.
The geology of the north Kimberley is dominated by sandstones, dolerites and other
volcanic rocks. Ancient rocks usually buried deep below Earth's surface are exposed
here. In places, these basement strata have been worn through by rivers, showing both
the long geological stability of the region which has allowed such features to be
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