Factors Affecting Flora Conservation - Victorian Environmental ...

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Humpback whale (Megaptera novaeangllae)
Like the southern right whale, the humpback
has been extensively hunted since the 1840s.
However, exploitation of this species
continued for longer, with more than 20 000
humpbacks taken by Australian shore stations
between 1949 and 1962. It is now estimated
that less than 2000 remain in the Southern
Hemisphere (Watson 1981). The species is
classified as endangered in both Australian
(CONCOM 1990) and Victorian waters.
Two virtually independent populations are
recognised and each spends the summer in
dift'erent areas of Antarctic waters. Each
population migrates north, one up the west
coast of Australia and the other up the east
coast, including the islands of the south-west
Pacific. The westem edge of the east coast
migration route follows the east coast of
Tasmania and New South Wales; however,
some animals enter Bass Strait and several
have been off the study area coastline.
Significant Taxa - Birds
Little penguin (Eudyptula minor)
The little penguin - the world's smallest
penguin - is the only species to breed in
Australia. It nests on islands and
occasionally on the coast of the southem
mainland and Tasmania, mainly in burrows
(Emison et al. 1987). It feeds at sea, tending
lo keep within 20 km of the coast, where it
catches small schooling fish and squid. In
Vicloria it breeds in suitable habitat along the
entire coastline. The largest breeding
colonies occur on Gabo Island in eastern
Little penguins
Victoria and on Phillip Island. In 1978
Harris and Norman (1981) estimated
approximately 20 000 little penguin burtows
in the State (an index of the size of the
breeding population), with about 30% on
PhUlip Island and 30% on Gabo Island.
Outside the breeding season, little penguins
may forage at sea for many weeks. Those on
Phillip Island appear to move mainly into
Port Phillip Bay in the non-breeding season
(Weavers in prep.).
The Phillip Island population has declined
substantially, but now shows signs of
stabilising (Dann in prep.). Substantial
efforts have been made to protect breeding
habitat and remove infroduced predators from
nesting colonies. The pilchard and anchovy
fishing industry is a potential competitor for
food resources, and a recent increase in the
commercial harvest of whitebait in Port
PhUlip Bay is of concern. Parts of Port
Phillip Bay and Bass Strait have primary
importance as foraging areas for adult little
penguins from Phillip Island. As an
important step to ensure conservation of the
colony on PhUlip Island, these areas require
special care to protect them from disturbance
(for example, oU spills, dredging,
overfishing).
Short-tailed shearwater (Puffinus tenuirostris)
The short-tailed shearwater is a sea-bird that
breeds exclusively in Ausfralia and lives at
sea for extended periods of time, feeding on
krill and small squid. It leaves each year in
May to winter in the northern Pacific and
returns in the following September to breed
on islands in south-eastern Ausfralia. In
Victoria, it breeds in excavated burrows in
soil under vegetation. Most nesting takes
place on Gabo Island, on islands off Wilsons
Promontory and off Port Fairy, and, in the
study area, on Phillip Island and French
Island. The largest numbers nest on the
north-western and southern coasflines of
Phillip Island (Andrew et al. 1984). The
number of nesting burrows (an index of the
population size) in Victoria was estimated in
1979 to be 1.45 million, or approximately
10% of die world total (Blakers et al. 1984).
At this time, the Phillip Island population
was estimated to be 540 OCX), or
approximately 30% of die State total (Harris
and Bode 1981). The majority of nesting
colonies occur on public land managed by
DCE. Factors such as a reduction in fish