O. Price et al., PATTERNS OF SPECIES COMPOSITION AND RESERVE DESIGN FOR A FRAGMENTED ESTATE - MONSOON RAIN-FORESTS IN THE NORTHERN-TERRITORY, AUSTRALIA, Biological Conservation, 74(1), 1995, pp. 9-19
Monsoon rainforests occur as small patches in the extensive Eucalyptus
-dominated landscape of northern Australia. This distribution presents
for formidable conservation problems. On a coarse scale (1:1,000,000)
, monsoon rainforests are currently relatively well represented in the
existing reserve network. However, inspection at a finer resolution s
hows that six of 16 variants are unreserved, and about 18% of plant sp
ecies have not been captured by the existing reserve system. Inspectio
n of inventory data for 1245 monsoon rainforest patches and 570 associ
ated plant species in the Northern Territory revealed very idiosyncrat
ic species composition for individual patches and a large number of re
stricted species (e.g. 20% of species are known from five of fewer pat
ches). Vertebrate distributions were less idiosyncratic, although samp
ling effort was far less intensive (45 patches and 58 associated speci
es). A minimum selection algorithm (CODA) was used to design a reserve
system which captures all occurrences of singleton species and at lea
st two representations for all other plant species. This selected 139
patches, with a total area of 6413ha. Inclusion of vertebrate records
increased the number of selections only marginally (to 141 patches). H
owever, this solution has profound practical limitations: the number o
f selected patches is probably politically unacceptable, the managemen
t required to protect the patches adequately is beyond the economic al
lowance for conservation of all existing NT parks, and the solution do
es not adequately consider the spatial arrangement of patches which is
probably critical for the maintenance of ecological processes. It is
not possible to design an efficient solution in which patches are clus
tered together. The conservation of the monsoon rainforest estate will
be reliant upon (1) the identification and active intense management
of particularly restricted and vulnerable species, and (2) conservatio
n planning for the whole landscape, which integrates monsoon rainfores
t conservation with that of the surrounding savanna woodlands.