WEST KIMBERLEY PLACE REPORT - Department of Sustainability ...

The National Heritage significance of these snails is discussed as part of vine thickets
below.
ANHAT analysis showed that the Prince Regent Nature Reserve is particularly rich in
possums, reptiles, Grevillea and the annual pavement plant families discussed under
the Kimberley Plateau above.
A nominator claimed that the Drysdale River National Park possessed high richness
and endemism for plants, mammals, reptiles, frogs, birds and freshwater fish.
ANHAT analyses partly supported this claim with the highest national endemism
score for reptiles recorded in the area. The area surrounding the Drysdale River
(including between Drysdale River National Park and north towards the coast)
possess one of the highest national endemism scores for bats (Vespertilionidae
family), whistler birds (Pachycephalidae), blind snakes (Typhlopidae), Dasyuridae
(carnivorous marsupials such as the northern quoll, Dasyurus hallucatus), frogs
(Myobatrachidae), lizards (families Varanidae, and Scincidae; genera Lerista and
Oedura), land snails (particularly for the families Pupillidae, Camaenidae and
Achatinellidae) and trapdoor spiders (Ctenizidae). ANHAT analysis also returned
nationally high values for the plant family Tiliaceae for endemism. Fish were also
confirmed as having an exceptionally high rate of endemism, drawing on information
in the literature.
The present day Kimberley Islands (dominated by the Buccaneer and Bonaparte
Archipelagos) were likely part of the mainland coast as recently as 8,000 years ago
(Nix and Kalma 1972). It is reasonable to assume therefore that the present day island
terrestrial fauna was derived from northwest Kimberley mainland fauna, and has been
evolving in isolation since the islands became separated (Burbidge et al. 1978).
The Kimberley islands, based on the evidence from recent biological surveys, are
proving to be a faunal refuge from human-induced changes. The Bonaparte and
Buccaneer archipelagos are particularly sheltered from threatening processes such as
changed fire regimes, weeds (with the exception of weeds such as Passiflora foetida)
and invasive species (for instance, the recent arrival of the cane toad to the
Kimberley). As such, the islands are likely to be important refuges for fauna and have
the potential as future safe havens for translocated species that are under threat on the
mainland (Gibson et al. 2008).
With the exception of mammals, a lack of historic biological data has likely obscured
the significance of richness and endemism values of the Kimberley islands. The true
significance is gradually being revealed through modern survey work. In December
2006, a multi-year biological survey led by WA Department of the Environment and
Conservation (DEC) began documenting the plants and animals of the largest
Kimberley islands. These and previous surveys have recorded 91 reptile (including
several specimens yet to be described), 22 frog and 21 mammal species (excluding
bats) on islands of the Kimberley (Gibson et al. 2008, Russell Palmer pers. comm.
Nov 2009). Mammal species such as the western chestnut mouse (Pseudomys nanus),
red-cheeked dunnart (Sminthopsis virginiae) and agile wallaby (Macropus agilis) are
newly recorded as existing on the Kimberley islands, the latter two being the first
records found on any Western Australian island. Collection has also included 63
species of Camaenid land snails, 27 of these being new to science with at least two
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