WEST KIMBERLEY PLACE REPORT - Department of Sustainability ...

of note. More tetrapod species are found at Ducabrook, in Queensland, however these
younger remains are isolated, fragmentary bones and are Carboniferous in age
(Thulborn et al. 1996). Some track sites preserve footprints ascribed to tetrapods, the
most impressive of which is the Devonian Genoa River site in Victoria; however
these do not preserve body fossils of the trackmakers (Clack, 1997). None of these
sites, except perhaps Wee Jasper, can compete with Gogo in the diversity and
preservation of its fauna and Wee Jasper does not yet provide the fine resolution or
diversity of early tetrapodomorph features. While Gogo does not contain true
tetrapods, it preserves fish that are ancestral to this group and clarifies the anatomical
transitions that took place at the base of this radiation.
The Gogo fossil sites have outstanding heritage value to the nation under
criterion (a) for important transitional fossils that document the evolution of
early tetrapodomorph fish.
CONTACT, CHANGE AND CONTINUITY
The biological significance of the west Kimberley
The west Kimberley has nationally important areas of vertebrate species richness and
endemism, particularly in the rivers of the north and west, along the northern
Kimberley coast and islands, and at Roebuck Bay. These will be discussed below in
detail.
These and other places in the region also provide important 'ecosystem services' as
biological refugia.
This report considers refugia broadly, in terms of the ecosystem service they provide,
adopting the three categories identified by Morton and colleagues (1995):
evolutionary; seasonal or 'ecological' (Morton et al. 1995); changes associated with
the presence or absence of particular predators or competitors.
Refugia of the west Kimberley provide habitat for numbers of endemic species,
isolated populations or species at the limits of their ranges in many important taxa.
They provide seasonal refuges, refuge from introduced species and human activities,
and refuge over geological timescales. These refugial environments include
mangroves, vine thickets, archipelagos and peninsulas, mound springs, wetlands,
ranges and caves or subterranean systems including karst environments. A number of
these refugia, discussed below, are nationally important and illustrate the physical,
ecological and cultural evolution of northern Australia in response to plate tectonics,
climate, invasive species and human impact.
Rocky coast biodiversity
The rugged, highly dissected nature of the sandstone dominated coast of the north
Kimberley, including rocky islands, bays and peninsulas, has over time provided the
opportunity for the development of a complex pattern of ecosystems. Collectively,
these ecosystems support plants and animals of greater richness and higher local
endemism than is found to the south and west in the drier savanna woodland
communities. ANHAT analysis has shown the northern Kimberley coast and islands
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