Arthur Rylah Institute for Environmental Research, Department of Sustainability and Environment. P.O. Box 137, Heidelberg, 3084, Victoria, Australia.
The State of Victoria is situated in the south-east of the Australian mainland and has a total coastline length of 2512 km of which 644 km is associated with islands (Geoscience Australia 2012). There are in excess of 90 islands, reefs and rock stacks located along this coast. All Victorian islands are classified as ‘coastal’ rather then ‘oceanic’ with the most isolated being Lady Julia Percy Island (also known as Deen Maar), located 8 km off shore. Management of the islands is largely the responsibility of state government agencies, Parks Victoria and to a lesser extent, the Phillip Island Nature Park. Five Victorian islands are privately owned, three are managed by local government and one by the Australian Government.
Victoria’s islands, reefs and rock stacks are formed from a variety of rock types. Lady Julia Percy is the remains of an extinct volcano and is formed from a basaltic lava shield and associated flows (Edwards et al 2004). The rock stacks found in the Port Campbell National Park (commonly known as The Twelve Apostles) are formed from marine limestone (Parks Victoria 1998). This section of coast, including these stacks are subject to collapse due to the highly erodible nature of the substrate (La Canna and Murphy 2005; Mawby and Tullberg 2009). Islands around Wilsons Promontory are part of the granite mass that extends through Bass Strait to north-eastern Tasmania. Gabo and Tullaberga Islands in the far east of the state are also of granitic origin (Douglas 1978; Rosengren et al 1981,). The majority of Victorian islands however, are formed from accumulations of mobile silts and sands with examples including the Swan Island group, Mud Islands and the islands found within the Nooramunga archipelago (Rosengren 1988, 1989). The Mud Islands group in Port Phillip Bay is known to have comprised variously of three or four islands throughout recorded history with tidal influences continually reshaping the inlets and lagoons (Menkhorst 2010; Bird 2011). French Island has a mixed geology with sand/silt accumulations in the north and a basalt promontory in the south forming both Tortoise Head and Rams Island (Rosengren 1984; Lacey 2008).
Tenure and jurisdictional arrangements
Most of the islands that are of ‘conservation significance’, are wholly managed by the state government. Exceptions to this include;
- French and Phillip Islands in Western Port which both have an extensive freehold component in addition to their conservation reserves.
- Middle, Merri and Griffiths Islands, near Warrnambool, are managed through local government.
- Sunday Island, in the Nooramuga archipelago, is freehold land owned by the Para Park Co-operative.
- Swan Island, near Queenscliff, is managed by the Australian Government.
The other privately owned islands within Victoria are; Sandstone and Elizabeth islands in Western Port, and Little Dog and Big Dog Island that are located in the Nooramunga archipelago. These privately owned islands have been extensively cleared of native vegetation and are utilised for agricultural or other enterprise.
Marine protected areas
Thirteen marine national parks have been declared in Victoria with seven of these proximate to terrestrial national parks. These marine protected areas encompass the rock stacks of The Twelve Apostles, the islands/ reefs within Western Port, the islands located in the waters surrounding Wilsons Promontory, Corner Inlet and the Nooramunga archipelago. The Cape Howe Marine National Park adjoins Gabo Island which is itself managed as a ‘Lighthouse Reserve’.
Databases such as the Victorian Biodiversity Atlas (Department of Sustainability and Environment – Victoria) and Birdata (Birdlife Australia) provide recent and historical records of species occurrence throughout Victoria. Birdlife Australia, a non-government body, have declared several Victorian island groups as Important Bird Areas (IBA) that are considered to be sites of global importance for bird conservation. These sites are Lawrence Rocks, islands in Swan Bay and Port Phillip Bay (Swan, Duck, Mud Islands, Popes Eye, South Channel Fort), Western Port islands, Corner Inlet (including the islands of the Nooramunga archipelago), Wilsons Promontory Islands, Gabo and Tullaberga Islands. The supporting data for these IBA declarations is provided at www.birdata.com.au. Monitoring of shorebird populations at some of these islands occurs annually and is reported in the literature (e.g. Herrod 2010, Menkhorst 2010) and is currently the subject of scientific review (D. Rogers, pers. comm.).
Key Conservation Values
Islands are frequently known for their depauperate or endemic fauna. French Island is a typical example with respect to mammalian fauna in that there are no natural populations of possums, bandicoots, dasyurids and only one macropod species, the Long-nosed Potoroo (Potorous tridactylus). Other regionally common species such as the Superb Fairy-wren (Malurus cyaneus) are absent.
Fauna and flora
There are no known endemic fauna recorded on Victorian islands. Perhaps the closest to an endemic species may be the Bush Rat (Rattus fuscipes) on Great Glennie Island which have been isolated for at least 7000 years and are considerably larger than their conspecifics on the adjoining mainland (J. Egan, pers. comm).
Endemic flora such as the French Island Spider Orchid (Caladenia insularis) have been described (Duncan et al 2006). The Victorian distribution of the Island Celery (Apium insulare) is limited to the Wilsons Promontory islands but it is also found throughout the Bass Strait islands and Tasmania. Similarly, the Coast Boronia (Boronia anemonifolia subsp. variabilis) is recorded on Snake Island but is also found interstate. The white-flowered coastal form of Coast Hollyhock (Malva preissiana s.s.) is a coprophilic plant associated with seabird rookeries on Mud Islands (Yugovic 1998; Menkhorst 2010; D. Cheal and D. Cameron, pers. comm.).
Threatened fauna, including migratory seabirds listed under international agreements such as CAMBA, JAMBA, Ramsar and ROKAMBA use Victorian islands, rock stacks and reefs. The islands also host important populations of terrestrial birds, reptiles and mammals; for example, King Quail (Coturnix chinensis), Swamp Skink (Egernia coventryi) and Long-nosed Potoroo are recorded on French Island (DSE 2012, Johnston pers. obs). Marine mammals such as Australian Fur Seal (Arctocephalus pusillus) and New Zealand Fur Seal (A. forsteri) maintain breeding colonies on Lady Julia Percy, The Skerries, Seal Rocks as well as Rag and Kanowna islands (Littnan and Mitchell 2002; Kirkwood et al 2010).
Marooning of native wildlife species has occurred in historical and continues to the current day. Menkhorst (2008) provides a detailed account of the history of Koala (Phascolarctos cinereus) management in Victoria. This has included marooning of Koalas on five coastal islands; Phillip, French, Snake, Chinaman and Quail, for conservation purposes. These populations increased rapidly in the absence of predation, particularly in populations that were free of chlamydiosis, to unsustainable levels given the available food resource (Menkhorst 2008). Mass starvation events were observed on Quail Island in 1944 and the population of >1300 Koalas was translocated to mainland sites. Capture and translocation of Koalas from Phillip Island was also initiated in 1944 and from French Island in between 1954 (Menkhorst 2008) with animals sent to both mainland and island locations, e.g. Kangaroo Island, South Australia. Translocations from French Island continued until 2011, with a chemical sterilisation program now in place (Menkhorst 2004; M. Douglas, pers. comm.). A two-stage process (sterilise in year 1, re-catch and translocate to mainland in subsequent years) has been used on Snake Island with the intention of removing this population completely (Menkhorst 2008).
Common Ringtail Possums (Pseudochirus peregrinus) were taken to French Island in the early 1900’s but this population had become extinct by the 1940s (Kirkwood and Johnston 2006). A non-breeding population of 16 Eastern-Barred Bandicoots (Perameles gunni) were released within the French Island National Park in July/August 2012. This species has no known historic presence on the island. This release was undertaken by the Victorian Government with the objective of determining whether this species can establish a secure population in the absence of predation by Red Foxes (Vulpes vulpes). However, predation by Cats (Felis catus) has caused four deaths in this study population while a further four animals have died after contracting toxoplasmosis (R. Hill, pers. comm.). Transmitter failure has lead to the ‘loss’ of a further two bandicoots. Two macropod species, Tasmanian Pademelon (Thylogale billardierii) and Red-necked Wallaby (Macropus rufogriseus) may have established small populations on Phillip Island following escapes from captivity (R. Kirkwood, pers. comm.). Eastern Grey Kangaroo (Macropus giganteus) have also been infrequently observed on Phillip Island.
Silver Gull (Chroicocephalus novaehollandiae) and Straw-necked Ibis (Threskiornis spinicollis) have established large breeding colonies following recovery of shrubby vegetation on the Mud Island group. These colonies may affect the breeding success of White-faced Storm Petrel (Pelagodroma marina) populations (Menkhorst 2010).
Populations of exotic species are expected to be present, or at least visit, all Victorian islands (Johnston 2008). Due to the proximity to the mainland, introduced bird species such as Common Blackbird (Turdus merula), Common Starling (Sturnis vulgaris) and European Goldfinch (Carduelis carduelis) are recorded on the majority of Victorian islands (Johnston 2008; DSE 2012;). Little or no management has been undertaken to address this presence given the ongoing control that would be required to prevent re-invasion. Parks Victoria unsuccessfully attempted to trap Common Myna (Acridotheres tristis) on French Island during the mid 2000s. This species is a recent arrival on the island (M. Douglas, pers. comm.) but has now established a low density population across the island. Indian Peafowl (Pavo cristatus) are also dispersing from private land into the National Park (M. Douglas, pers. comm.). No populations of exotic herpetofauna are recorded from Victorian islands (Victorian Biodiversity Atlas 2012).
Intentional release of exotic species onto Victorian islands has taken place since the arrival of Europeans and continues to the present day. Brown Hare (Lepus capensis) were released on Phillip Island between 1861 -1863 (Lever 1992). Fallow Deer (Dama dama) were also released onto Phillip Island in 1851, prior to the establishment of the Acclimatisation Society of Victoria; however, this population died out ~1920 (Bentley 1988; Gooch 2006). Sambar (Cervus unicolor) were reported to have been introduced to French Island by 1859 (Bentley 1998; Anonymous in Gooch 2006). Like all deer species, Sambar are adept swimmers and have been reported to swim between mainland, French and Phillip Islands (Bentley 1998). Further releases of deer onto Snake Island took place with Hog deer (Axis porcinus) in 1856- 6 (Lever 1992), Sambar in 1866 (Bentley 1988) and Fallow Deer onto Sunday Island in 1967 (Menkhorst 1996).
In Victoria, deer species are afforded protection under the Wildlife Act 1975 (Wright et al 2009) which differs from the policy adopted in other states, such as South Australia which regulates feral deer as an invasive species that must be controlled (Williams 2009). While deer hunting in Victoria is permitted ‘in season’, this activity is heavily regulated and government enforcement officers take an active role in reducing ‘poaching’ (Department of Primary Industries 2012). The use of equipment such as night vision aids, including spotlights, and tracking collars on dogs “is considered highly unethical and is inconsistent with the concept of ‘fair chase’ ” (Department of Primary Industries 2012). No ‘legal’ recreational deer hunting occurs on Victorian coastal islands other than that undertaken on Sunday Island although there is interest from the hunting lobby to open Snake Island to a balloted hunting program for Hog Deer (McLennan 2012; Snake Island Hog Deer Project Group 2012). The Department of Sustainability and Environment (Victoria) does issue control authorities where damage can be attributed to deer although this is more common with mainland agricultural impacts rather than island-based biodiversity protection (e.g. Lindeman and Forsyth 2008). Rangers from French Island National Park has previously been issued with this permit. The ‘Reduction in biodiversity of native vegetation by Sambar (Cervus unicolor)’ was listed as a Potentially Threatening Process in 2007. The benefits of this declaration are yet to be seen.
Hog and Fallow Deer populations on the privately-owned Sunday Island are managed by the Para Park Co-operative Game Reserve Ltd. This organisation was established in 1965 and purchased the 1540 ha island (Bentley 1998). The stated objectives of the co-operative include; “to conserve the game animals and birds, which at present inhabit the island. To complement these with other game species … [and] to control noxious animals and birds” (Parapark 2012). Bentley (1988) reports that Hog Deer have been observed swimming between Nooramunga islands and Wilsons Promontory. It is likely that deer from the Parapark population disperse onto adjoining islands and mainland areas. Automated cameras have also recently detected Hog Deer on Phillip Island (S. Murphy, pers. comm.).
Clarke (2012) has identified that the small mammals, other than bats, present on Gabo Island are both exotic, being the Brown Rat (Rattus norveigicus) and House Mouse (Mus musculus). These species may be influencing breeding success and population viability of seabird species such as Little Penguin and Short-tailed Shearwater. Successful eradication programs in Victoria include removal of European Rabbits (Oryctolagus cuniculus) on Mud, Churchill, Rabbit and Citadel Islands, feral cats on Gabo Island (Twyford et al 2000) and feral pigs (Sus scrofa) on French Island (M. Douglas, pers. comm). The latter was required following intentional release of pigs during the late 1990’s. It was undertaken by Parks Victoria using a variety of techniques including cage trapping and active hunting. Feral pigs have also been released on Quail Island on at least two occasions recently (2010 and 2012) with follow-up removal projects undertaken by contractors with support from Parks Victoria (M. Legg, pers. comm.). The latter release is thought to involve 10 pigs with at least one of these still present on the island (M. Legg, pers. comm.). The removal of rabbits from Rabbit Island, achieved using poison baiting following a myxomatosis epidemic, occurred in 1966. This led to improved soil stability and an increase in floral diversity including return of the shrub layer (Norman 1988). Rabbits were also removed from Citadel Island at around the same time (Norman 1988; Williams et al 1995). The rabbit population on the Mud Islands was extinct by 1988 following control activity (baiting) during the 1970s (Menkhorst 2010). Rabbit browsing on this island group led to loss of shrubby vegetation and the creation of an extensive herbfield which was occupied by a large colony of White-faced Storm Petrel. Shrubs subsequently overgrew the herbfield following release from rabbit browsing (Menkhorst 2010). This author also notes that a single cat lived on this island group during the 1980s and that exotic rodents have not become established. The owner of Elizabeth Island has indicated that rabbits were previously present but are presumed to have died out during the late 2000’s without direct human intervention. This extinction occurred during prolonged drought, but may have been assisted by disease epidemic and predation by raptorial birds (A. Tillig, pers. comm.). A population of House Mouse remains on the island. There have been several unsuccessful attempts at eradicating the rabbit population on Lady Julia Percy Island. The procedures utilized do not appear to have met the specific principles required to successfully achieve eradication (Clout and Veitch 2002; Morrison et al 2011) as compared to a conventional maintenance control program. Particular examples that lead to failure of the eradication program include:
- The pattern of bait spread that left a proportion of rabbits not ‘at-risk’, particularly those rabbits that used the rocky shelves along the cliffs;
- Fire was used to provide for improved shooting opportunities but subsequently promoted the growth of highly palatable vegetation which precluded any further use of baiting;
- Follow-up control of surviving rabbits, even when the population was relatively low, was ‘piggy-backed’ on island visits by other projects rather than dedicated effort being undertaken. Insufficient resources were directed at provision of skilled expertise ‘on-island’; and
- The insufficient training and practices that led to project inefficiencies and ultimately the withdrawl of agency support (J. Amos, pers. comm.).
Other introduced mammals, essentially domesticated livestock, are no longer present on Lady Julia Percy Island. No rodents have been trapped or otherwise observed during annual visits over 10 years (R. Kirkwood, pers. comm.). Rabbit populations are managed on an ‘ongoing control’ basis on both French and Phillip Islands by both agency and freehold land managers. There are no current proposals to work towards eradication of rabbits on these larger islands.
Exotic plants are commonly found on Victorian islands. Radiata Pine (Pinus radiata) and Pinaster Pine (P. pinaster) were planted on French Island by prisoners encamped at the McLeod Prison Farm during the 1900’s (Gooch 2006). Felling of existing plantations is an ongoing process from within the National Park and the regrowth of seedlings is managed through a planned burning regime (Weir and Heislers 1998). An African Boxthorn (Lycium ferocissimum) infestation has been largely removed by Parks Victoria and volunteers on Tortoise Head where it was known to ensnare Short-tailed Shearwaters. All adult plants have been removed with follow-up work undertaken annually to remove seedlings (M. Douglas, pers. comm.). The French Island Landcare Group assists with management of invasive plants on freehold areas of the island. Boxthorn was deliberately planted as the ‘last line of defence’ during the 1880’s on the man-made South Channel Fort in Port Phillip Bay (Parks Victoria 2006). Recent restoration works to infrastructure on the island included removal of boxthorn and other weeds (Tuohy 2011) to improve the habitat for sea birds.
The Phillip Island Nature Park Environment Management Draft Plan 2012 –2017 (PINP 2012b) notes that there four nationally significant and 24 declared noxious weeds within the conservation reserves it is responsible for. Additional weed species are likely present on other parts of the island with volunteer groups such as Bass Coast Landcare assisting land managers to control these species.
Mirror bush (Coprosma repens) and Cape Wattle (Paraserianthes lophantha) have formed dense thickets on Cliffy Island and are becoming established on other Wilsons Promontory islands (N. Schumann, pers. comm.). These infestations reduce the area available to ground- nesting seabirds such as Short-tailed Shearwater. Similarly, the native Coastal Tea tree (Leptospermum laevigatum) is present on Citadel island and has the ability to limit the available nesting sites for seabirds (N. Schumann, pers. comm.). The spread of seeds from some of these plant species is likely to be assisted by birds.
The proximity of Victoria’s coastal islands to the mainland facilitated use of the islands by indigenous people for both food gathering and spiritual purposes. Lady Julia Percy Island and the adjoining mainland, known as Deen Maar, are a notable example and have been declared an Indigenous Protected Area reflecting the historical and spiritual significance of the area to the Gunditjmara people. The island is considered to be the place where Bunjil, the Creator, left the world and where the spirits of their dead await rebirth (Weir 2009; SEWPaC 2012).
Archaeological surveys have been conducted on an individual basis by local land managers in association with indigenous communities and other cultural heritage specialists (P. Fricker, pers. comm.). Evidence of indigenous occupation of the coastal islands in terms of midden sites and artefact scatters are known from many islands (e.g. French Island reported in Parks Victoria, 2004). Indigenous communities continue to use islands, such as Lady Julia Percy, for traditional reasons.
Lighthouses were constructed on four islands; Gabo Island (1853), Griffiths Island (1859), Cliffy Island (1884) and Citadel Island (1913) (Lighthouses of Australia, 2012). The Citadel Island light was withdrawn from service in 1982 while the others have been fully automated. The establishment and maintenance of this infrastructure on islands has lead to changes in vegetation, transport of domestic animals and invasive species.
Other noteworthy historical uses of islands include the site of the first farming activity by Europeans in Victoria on Churchill Island when Lieutenant James Grant established a cottage and grew wheat and corn from 1801 (Lee 1915). Gooch (2006) documents the discovery and development of French Island. An ambitious social welfare project included the allocation of land in 1893 on the island to people with no farming background. Seven villages, with a population of approximately 200 people, were established but the scheme was largely a failure. Agricultural enterprises such a chicory production, livestock grazing and seagrass harvesting continued.
The largest Victorian islands, French and Phillip (173 and 103 km2 respectively) are both located in Western Port and have considerable areas of freehold ownership. Phillip Island has been extensively developed for agricultural and tourism enterprises and residential uses. The resident population of approximately 10,000 people can increase to >50,000 during peak summer periods (Phillip Island Visitor Information Centre 2012).
In contrast to this, the absence of a bridge or other ‘attractions’ such as beaches has led to a greatly reduced development activity on French Island. Vegetation clearance was historically undertaken for agricultural and timber-harvesting purposes (Gooch 2006; Lacey 2008) however this practice is now regulated (Department of Planning and Community Development 2011). The original conservation reserve was declared in 1982 and the current French Island National Park encompasses two-thirds (121 km2) of the island (Weir and Heislers 1998). There is a resident population of ~90 people which is supplemented by a similar number of absentee landowners. Access is achieved via boat (passenger ferry, vehicular barge) or light aircraft. The island is an ‘unincorporated territory’ and as such there is no local government administration. This has led to complexities in administration of the Domestic Animals Act 1994 as the regulations and powers in this Act are conferred to local government. This Act requires animals to be permanently identified, registered and prevented from roaming from the owner’s property but in the case of French Island, these requirements are currently unenforceable. The management of domestic animals, with particular reference to cats, on French Island is effectively unregulated. This has lead to unrestricted breeding and subsequent impacts on native species via predation and disease transmission. In actuality, management of straying and feral cats across the island has defaulted to Parks Victoria and more recently, also the French Island LandCare Group.
Livestock are grazed on two of the crown-managed islands, namely Gabo and Snake Island. In addition, the Phillip Island Nature Park operates a ‘heritage farm’ tourism enterprise on Churchill Island. Grazing of a variety of livestock species occurs on freehold land on Phillip, French, Big and Little Dog islands. Agricultural and domestic species have either been removed or died out on other islands where they previously existed, such as; Lady Julia Percy, Griffiths and Sunday Islands.
Human visitor impacts
The development of infrastructure to support tourism enterprises has led to a range of impacts. The largest of these is on Phillip Island (and includes Churchill Island) which records over 3.5 million visitors annually (Phillip Island Visitor Information Centre 2012) with many of these visitors intending to experience natural attractions (viewing of Little Penguins, seals, surf beaches, landscapes, etc). This visitation is a major contributor to the local and state economies (Phillip Island Nature Park 2012a). The scale of development on Phillip Island to support the tourism industry is not replicated on any other Victorian island.
Tourism enterprises also seek to highlight the natural values of the French Island but are undertaken at a scale appropriate to the patronage. The French Island National Park receives less than 2000 visitors annually and is supplemented by an additional ~2500 visitors attracted to the various accommodation, food industry and guided tour enterprises on the French Island (M. Douglas, pers. comm.). A minority of these visitors bring their own car onto the island. The only other vehicle-accessible island is Swan Island although access to the causeway is regulated due to the presence of a Department of Defence facility.
At the lower end of the tourism-impact scale, some of the more accessible islands such as Middle and Griffiths have walking tracks and fencing installed to limit visitor impacts through sensitive areas such as seabird colonies.
Access to islands is governed by regulations associated with land tenure, proximity to mainland and ease of arrival. With respect to regulations, these differ between the various tiers of declared conservation reserve but most will generally prohibit transport of animals to the islands. The exception to this regulation is Snake Island which is subject to cattle agistment and an annual stock muster that involves cattle, horses and working dogs. In cases where the island is managed wholly as National Park, such as those around Wilsons Promontory, an authorisation under the National Parks Act 1975 is required to land. Domestic animals are permitted on French and Phillip Islands but are required to be kept out of the conservation reserve areas.
The absence of secure anchorage or beach access affords a degree of protection for islands and rock stacks that are located in open waters such as Lady Julia Percy, Twelve Apostles, the Wilsons Promontory islands and Tullaberga Island. The islands within Corner Inlet and the Nooramunga archipelago and Mud Island group are more readily accessible to arrivals by small vessel given the relatively sheltered waters.
Maintaining an effective quarantine is a challenge as many islands are accessible at low tide or are ‘attached’ to the mainland via a man-made structure. The islands within the Nooramunga archipelago provide a good example. Foxes were reported to be eradicated from the ~1900 ha Saint Margaret Island (Parks Victoria 1999). However given the proximity to the mainland there is a requirement for ongoing maintenance effort to counter reinvasion.
Parks Victoria has since undertaken poison baiting for foxes in the ‘Corner Inlet Ramsar site’ which included baiting on both island and mainland areas adjacent to Saint Margaret and the sand barrier island unofficially known as ‘Dream Island’ (Department of Sustainability and Environment 2010; D. Farrar, pers. comm.).
Similarly, a network of permanent baiting stations established for fox control on Quail Island and adjoining mainland has led to the recovery of Southern Brown Bandicoot (Isoodon obselus) populations (M. Legg, pers. comm.) as part of the Western Port Ramsar Protection Program.
Bridges and causeways can provide for rapid access for invasive species onto islands. A 640 m bridge was built in 1969 that connects the towns of Newhaven on Phillip Island and San Remo. A motion-sensitive video camera system was trialed on this bridge to determine whether foxes were using the bridge but was removed following repeated vandalism (R. Kirkwood, pers. comm.). Despite the presence of the bridge, genetic studies have suggested that the fox population on Phillip Island is relatively isolated with migration of a fox occurring at a rate of one fox every five years (Berry and Kirkwood 2010; Lade et al 2008).
The accessibility of Middle Island to foxes and dogs has contributed to near-loss of the resident Little Penguin (Eudyptula minor) colony. This population had 292 active nesting burrows in 1999/2000 (Overeem and Wallis 2003, 2007) but had decreased to <10 birds in 2006 (van Bommel 2010). Guardian dogs (maremmas) were assessed to determine whether the presence of the dog was sufficient to protect penguins from predation (van Bommel 2010). The program has not been without setbacks (10 penguins were killed by the dogs in 2007) or legislative restrictions (i.e. use of electronic collars for virtual fencing is limited to a maximum of 12 hours per day) but the desired outcome of protecting penguins and Short- tailed Shearwaters (Puffinus tenuirostris) has been achieved. A rigorous dog training and handling regime is now used. The penguin population is reported to have increased to ~120 birds with no fox activity detected since the introduction of dogs onto the island (van Bommel 2010).
Given the number of islands along the Victorian coast, there is a gradient of impacts associated with human and non-human factors. Highly altered islands such as Phillip seek to achieve a balance between development and sustainability through regulations that facilitates management of biodiversity hotspots such as the sea bird and seal habitats. A 25 year government-funded campaign to acquire all private land on the Summerland Peninsula was completed in 2010. The objective of this program was to reduce threats to this penguin population (habitat destruction, predation, road kill etc) and simultaneously work towards restoration of this habitat (McPhee and Bloomfield 2004). Reducing predation of penguins by invasive species is the objective of another program that seeks to eradicate foxes from the island (Kirkwood et al 2005). The penguin population appears to responding positively with 2011 producing the highest count of the 35 year monitoring program. (Phillip Island Nature Parks 2012a). No penguins have been recorded killed by foxes in the last three years although predation by cats does remain an ongoing issue (S. Murphy pers. comm.). This program is being reviewed by an independent panel to verify that the science and methodology are consistent with achieving eradication (P. Dann, pers. comm.).
On French Island, increased investment by Parks Victoria into cat control has facilitated more effective programs that led to trapping and removal (i.e. euthanasia) of significant numbers of cats across the island; 39 (2009), 63 (2010), 121 (2011) and 257 (2012) (S. Coutts, pers. comm.). Follow-up trapping and shooting coordinated by the French Island LandCare Group caught a further 127 cats during 2012 (J. Tresize, pers. comm.). Management agencies seek a situation where the management (desexing, confinement) of domestic animals by landowners is improved on this island. Subsidised sterilisation of cats is currently being considered by island residents.
French Island National Park also has feral Goat (Capra hircus) and Sambar populations that are subject to opportunistic control by Parks Victoria. Browsing damage, pugging of wetland and saltmarsh and the creation of wallows are commonly observed in areas where these species frequent (Johnston pers. obs.). The distribution and activity of feral goats has been the subject of an academic study (Butler 2005) and it is likely that an appropriate resourced program could remove this population. Techniques used on Kangaroo Island, South Australia (Markopoulos et al 2009; Masters et al 2012) and internationally (Parkes 1990; Campbell and Donlan 2005) could be readily adapted to this island. Parkes and Forsyth (2011) suggest that eradication of Sambar from French Island is technically feasible but that success would be subject to community and agency support.
Management of fire on Victorian islands is generally less of a management priority on most islands than control of populations of invasive species. On French Island, Parks Victoria uses fire to suppress growth of pine species in addition to other ecological or fuel reduction (asset protection) objectives. Similar outcomes are adopted by the Phillip Island Nature Park. Wildfires are infrequent on the smaller, unpopulated islands and are generally left to burn out.
The biosecurity aspects relating to Victorian islands are currently poorly addressed. There are no enforced requirements to conduct searches of equipment or vehicles (including boats and aircraft) that access islands other than the anticipated compliance with permit conditions.
This situation should be reviewed and improved procedures introduced across prioritised islands, such as those that where exotic rodents are currently absent. A wash down for vehicles accessing French Island may have prevented transport of Cinnamon Fungus (Phytophora cinnamoni) onto the island. The presence of this fungus on the island was first confirmed in 2010 (M. Douglas, pers. comm.).
Several opportunities to restore island habitats by eradicating the invasive species are apparent. Each would require thorough planning and peer review component prior to initiation of operations and necessarily include analysis of the likelihood of re-invasion. An understanding of the reasons for previous failures, both within Victoria (i.e. rabbits on Lady Julia Percy) and internationally, (see the Database of Island Invasive Species Eradications at http://eradicationsdb.fos.auckland.ac.nz/ ) would be included in this analysis.
These sites are:
- Red Fox on Phillip Island (currently in progress);
- European rabbits on Lady Julia Percy Island;
- Feral Goats (and Sambar) on French Island; and
- Brown Rats, House Mouse, cattle and invasive grasses on Gabo Island
There are a range of challenges (regulatory, geographical, social and financial) associated with each of these potential operations but as with many similar ventures the over-riding challenge is to confirm agency support for the program. Co-funding island restoration programs between the private sector through philanthropic donations and government, such as occurred with the Tasman Island restoration may be worthy of investigation (Tasmanian Parks and Wildlife Service 2009).
Preventing the arrival of new species to high conservation value islands in Victoria should also remain a priority for management agencies. It is surprising that exotic rodents have established populations on so few of the Victorian islands, particularly given the various land use histories. Investment in maintaining the ‘pest-free’ status of these islands may be more cost-effective than dealing with outbreaks at later dates (Commonwealth of Australia 2009).
Management plans are in place for the Victorian islands that are of conservation significance. These plans may include areas of mainland and neighbouring islands (i.e. Wilsons Promontory National Park) or include a large number of islands (i.e. Nooramunga Marine and Coastal Park Draft Plan) or a component of an island (i.e. French Island National Park). These plans are subject to scheduled review. Delivery of the stated objectives in these plans is always subject to adequate resourcing and this remains the greatest challenge in effectively managing Victoria’s islands as biodiversity hotspots.
I am indebted to the many people who have provided insights to Victoria’s islands that are represented here as personal communications; David Cheal, David Cameron, Peter Menkhorst, Richard Hill and John Amos (Department of Sustainability and Environment – Victoria); Peter Dann, Roger Kirkwood and Stuart Murphy (Phillip Island Nature Park); Mick Douglas, Scott Coutts, David Farrar, Lachlan Jackson and Pat Fricker (Parks Victoria), Nicole Schumann and Lachlan Clarke (Deakin University), Anne Tillig (Elizabeth Island), Julie Tresize (French Island LandCare Group), Chris Chandler (French Island), James Egan (Acacia Environmental Management and Consultancy) and Malcolm Legg (Mal’s Environmental and Ecological Services).
This paper benefited from recommendations suggested by Peter Menkhorst, Matthew Bruce and Lindy Lumsden.
Bass Coast (2012) website accessed 3 December, 2012. http://www.basscoast.vic.gov.au/
Bentley, A. (1998) An Introduction to the deer of Australia. The Australian Deer Research Foundation Ltd. Croydon. 367p.
Berry, O. and Kirkwood, R. (2010). Measuring recruitment in an invasive species to determine eradication potential. Journal of Wildlife Management 74(8): 1661-1670.
Bird, E. (2011) Changes on the Coastline of Port Phillip Bay. Office of the Environmental Monitor. Department of Sustainability and Environment, Victoria. ISBN 978-1-74287-020-5.
Butler, K. (2005) Distribution, habitat use and diet of the feral goat (Capra hircus) in the French Island National Park: implications for management. Bachelor of Science (Honours) thesis. Department of Zoology, University of Melbourne.
Campbell, K., and Donlan, C. (2005). Feral goat eradications on islands. Conservation Biology 19(5): 1362-1374.
Clarke, L. (2012) Invasive rodents on Gabo Island: A study of their presence, distribution and activity. Bachelor of Environmental Science (Honours) thesis. School of Life and Environmental Sciences, Deakin University.
Clout, M. and Veitch, C.R. (2002) Turning the tide of biological invasion: the potential for eradicating invasive species. In: Veitch, C.R. and Clout, M.N. (eds.) Turning the tide: the eradication of invasive species. IUCN SSC Invasive Species Specialist Group. IUCN, Gland, Switzerland and Cambridge, UK. Viii +414pp.
Commonwealth of Australia (2009). Background document for the threat abatement plan to reduce the impacts of exotic rodents on biodiversity on Australian offshore islands of less than 100000 hectares. Department of Environment, Water, Heritage and the Arts, Canberra.
Department of Planning and Community Development (2001). Planning for French Island, Sandstone Island and Elizabeth Island: A User’s Guide ISBN 978-1-921940-10-1. Victoria
Department of Primary Industries (2012) Victorian Hunting Guide 2012. website accessed 3 December 2012. http://www.dpi.vic.gov.au/game-hunting/about-game- hunting/publications/hunting-guide
Department of Sustainability and Environment (2010). Media Release: Caring for our Country Corner Inlet – Ramsar site. 20 Sept 2010. Website accessed December 3, 2012. http://www.docstoc.com/docs/79631521/pr_1424
Department of Sustainability and Environment (2012) The Victorian Biodiversity Atlas. Website accessed 3 December 2012. https://vba.dse.vic.gov.au/vba/
Douglas, J.G. (1978). Geology of Tullaberga Island and the adjacent mainland. F.D. Atkinson, Melbourne.
Duncan, M., Pritchard, A. and Coates, F. (2006). National Recovery Plan for Fifteen Threatened Orchids in Victoria and South Australia. Department of Sustainability and Environment, Melbourne.
Edwards, J., Cayley, R.A. and Joyce, E.B. (2004). Geology and geomorphology of the Lady Julia Percy Island Volcano, a late Miocene submarine and subaerial volcano off the coast of Victoria, Australia. In: Environmental History of the Newer Volcanic Province of Victoria. Edited by: Kershaw, A.P. 116: 15–35. Proceedings of the Royal Society of Victoria.
FICA (2012) French Island Community Association. Website accessed 3 December, 2012. http://www.frenchislandinfo.com/
Geoscience Australia (2012) Coastline lengths. Website accessed 3 December, 2012. http://www.ga.gov.au/education/geoscience-basics/dimensions/coastline-lengths.html
Gooch, R. (2006) Frontier French Island. Prahran Mechanics Institute Press. Windsor, Victoria, 335p.
Herrod, A. (2010). Migratory shorebird population monitoring within the Port Phillip bay (Western Shoreline) and Bellarine Peninsula Ramsar Site. Birds Australia Report, Melbourne.
Johnston, M. (2008) Introduced animals on Victorian islands: improving Australia’s ability to protect its island habitats from feral animals. Arthur Rylah Institute for Environmental Research Client Report. Department of Sustainability and Environment. Victoria. ISBN. 978- 1-74208-274-5.
Kirkwood, R. and Johnston, M. (2006). Terrestrial mammals of Phillip and French Islands, Western Port, Victoria. The Victorian Naturalist 123(3): 146-156.
Kirkwood, R., Pemberton, D., Gales, R., Hoskins, A., Mitchell, T., Shaughnessy, P.D. and Arnould, J.P.Y. (2010). Continued population recovery by Australian fur seals. Marine and Freshwater Research 61: 695-701.
La Canna, X. and Murphy, M. (2005) Ninth Apostle crumbles. The Age newspaper. July 4, 2005. Website accessed December 3, 2012. http://www.theage.com.au/articles/2005/07/03/1120329326001.html
Lacey, G. (2008) Reading the Land. Australian Scholary Publishing, North Melbourne. ISBN 978 1 74097 155 3.
Lade, J.A., Murray, N.D., Marks, C.A., and Robinson, N.A. (2008). Microsatellite differentiation between Phillip Island and mainland Australian populations of the red fox Vulpes vulpes. Molecular Ecology, 5(1), 81-87.
Lee, I. (1915). The logbooks of the ‘Lady Nelson’, with the journal of her first commander Lieutenant James Grant., London: Grafton, p. 48. Website accessed 3 December, 2012. http://www.archive.org/stream/logbooksofladyne00leei#page/n13/mode/2up
Lever, C. (1992). They dined on Eland. The Story of the Acclimatisation Societies. Quiller Press, London. 224p
Lighthouses of Australia. Website accessed December 3, 2012.
Lindeman, M.J. and Forsyth, D.M. (2008) Agricultural impacts of wild deer in Victoria. Arthur Rylah Institute for Environmental Research Technical Report Series No. 182. Department of Sustainability and Environment, Heidelberg, Victoria.
Littnan, C.L. and Mitchell, A.T. (2002). Australian and New Zealand fur seals at The Skerries, Victoria: recovery of a breeding colony. Australian Mammalogy 24: 57-64.
Markopoulos, N., Masters, P. and Florance, B. (2009). Trial eradication of feral goats on Kangaroo Island: Progress report on 2006–2008 control activities. Unpublished report to the Kangaroo Island Natural Resources Management Board.
Masters, P., Markopoulos, N. and Florance, B. (2012). Feral goat eradication on Kangaroo Island, South Australia. In: Island Arks Symposium II.
Mawby, N. and Tullberg, J. (2009) Another apostle collapses – seven limestone stacks left of the Twelve Apostles. Herald Sun newspaper. September 25, 2009. Website accessed 3 December, 2012. http://www.heraldsun.com.au/news/another-apostle-collapses-seven- limestone-stacks-left-of-the-twelve-apostles/story-e6frf7jo-1225779728441
McLennan, C. (2012) Deer hunters look to Snake Island. Weekly Times newspaper. November 27, 2012. Website accessed 3 December, 2012. http://www.weeklytimesnow.com.au/article/2012/11/27/551122_national-news.html
McPhee, S. and Bloomfield, T. (2004). Strategy for the Eradication of Foxes from Phillip Island, Part 2: Detailed Review of the Eradication Strategy. Unpublished report prepared for the Phillip Island Nature Park.
Menkhorst, P. (1996) Mammals of Victoria. Distribution, ecology and conservation. Oxford University Press.
Menkhorst, P. (2004) Victoria’s koala management strategy. Department of Sustainability and Environment, Victoria, 2004.
Menkhorst, P. (2008) Hunted, marooned, re-introduced, and contracepted: A history of Koala management in Victoria. In: Too Close for Comfort: Contentious Issues in Human-wildlife Encounters (Eds. D.Lunney, A.Munn and W.Meikle), pp. 73–92. Royal Zoological Society of NSW, Mosman, NSW.
Menkhorst, P. (2010). A Survey of Colonially-breeding Birds on Mud Islands, Port Phillip, Victoria, with an annotated list of all terrestrial vertebrates. Arthur Rylah Institute for Environmental Research, Technical Report Series Number 227. Department of Sustainability and Environment, Heidelberg, Victoria.
Morrison, S.A., Faulkner, L.A., Vermeer, L.A., Lozier, L. and Shaw, M.R. (2011) The essential non-science of eradication programmes: creating conditions for success. In: Veitch, C.R., Clout, M.N. and Towns, D.R. (eds.) Island Invasives: Eradication and Management. Proceedings of the International Conference on Island Invasives. Gland, Switzerland: IUCN and Auckland, New Zealand: CBB xii +542pp.
Norman, F.I. (1967). The interactions of plants and animals on Rabbit Island, Wilson’s Promontory, Victoria. Proceedings of the Royal Society of Victoria. 280, 193-200.
Norman, F.I. (1988). Long term effects of rabbit reduction on Rabbit Island Wilson’s Promontory Victoria. Victorian Naturalist, 105, 136-141.
Overeem, R.L. and Wallis, R.L. (2003). Little Penguin Eudyptula minor at Middle Island, western Victoria: current status. The Victorian Naturalist 120, 76–83.
Overeem, R. and Wallis, R. (2007). Decline in Numbers of Little Penguin ‘Eudyptula minor‘ at Middle Island, Warrnambool, Victoria. The Victorian Naturalist, 124(1), 19.
Parapark (2012) Parapark – Sunday Island. Website accessed 3 December 2012. http://www.parapark.com
Parkes, J.P. (1990). Eradication of feral goats on islands and habitat islands. Journal of the Royal Society of New Zealand, 20(3): 297-304.
Parkes, J. and Forsyth, D. (2011). Eradicating new populations of introduced large herbivores in Victoria: Part II Feasibility of eradicating Sambar deer on French Island. Unpublished report for the Department of Primary Industries, Victoria. 19p
Parks Victoria (1998) Port Campbell National Park and Bay of Islands Coastal Park Management Plan. ISBN 0 7311 3133 9.
Parks Victoria (1999) Rangers outfox a wily islander. Canopy 9: 2. ISSN 1329 9239
Parks Victoria. (2006) South Channel Fort Conservation Management Plan. Unpublished report. Website accessed 3 December 2012. http://parkweb.vic.gov.au/__data/assets/pdf_file/0019/313435/South-Channel-Fort- Conservation-Management-Plan.pdf
Parks Victoria (2004) French Island National Park Aboriginal Cultural Heritage Assessment. Unpublished report by Andrew Long and Associates. 69p.
Parks Victoria (2012) Gabo Island Light Station Reserve. Parknotes Visitor Guide, Melbourne. Phillip Island Nature Parks (2012a) Annual Report 2011-12. ISSN 2200-8756. 76p.
Phillip Island Nature Parks (2012b) Phillip Island Nature Parks Environment Plan 2012 -2017. Draft. 107p
Phillip Island Visitor Information Centre (2012) Phillip Island. Official Visitor Guide. 33p.
Rosengren, N.J., McRae-Williams, M.S. and Kramers, S.M. (1981) Sites of Geological and Geomorphological Significance in Central Gippsland, Environmental Studies Series No. 341, Ministry for Conservation, Victoria.
Rosengren, N.J. (1984) Sites of Geological and Geomorphological Significance in the Westernport Bay Catchment, Department of Conservation, Forests and Lands, Melbourne.
Rosengren, N.J. (1988) Sites of Geological and Geomorphological Significance on the coast of Port Phillip Bay, Victoria. Technical Report Series, Making the Most of the Bay. Ministry for Planning and Environment, Victoria.
Rosengren, N.J. (1989). Sites of Geological and Geomorphological Significance in the South Gippsland Marine and Coastal Parks. Unpublished report.
SEWPaC (2012) Deen Maar Indigenous Protected Area. Website accessed 3 December, 2012. http://www.environment.gov.au/indigenous/ipa/declared/deen-maar.html
Snake Island Hog Deer Project Group (2012) Balloted hog deer hunting on Snake Island. Website accessed 3 December 2012. http://snakeisland.org.au/
Tasmanian Parks and Wildlife Service (2009) Conservation fund contributes to cat eradication planning. In: Buttongrass Newsletter, June 2009. Website accessed 3 December 2012. http://www.parks.tas.gov.au/file.aspx?id=13904
Tuohy, S. (2011) South Channel Fort reopens. Coastline 56. Department of Sustainability and Environment, Victoria. ISSN 1329 0835.
Twyford, B.K.L., Humphrey, P.G., Nunn, R.P. and Willoughby, L. (2001). Eradication of Feral Cats (Felis catus) from Gabo Island, south-east Victoria. Ecological Management & Restoration, 1(1), 42-49.
van Bommel, L. (2010) Guardian Dogs: Best practise manual for the use of Livestock Guardian Dogs. Invasive Animals CRC, Canberra.
Weir, I. and Heislers, A. (1998). French Island National Park Management Plan. Parks Victoria. Kew, Victoria, Parks Victoria. 55 p.
Weir, J.K. (2009) The Gunditjmara land justice story. Australian Institute of Aboriginal and Torres Strait Islander Studies. Native Title Research Unit, No. 1/2009. ISBN: 9 7808 5575 4396.
Williams, C.K., Parer, I., Coman, B.J., Burley, J. and Braysher, M.L. (1995). Managing Vertebrate Pests: Rabbits. Bureau of Resource Sciences / CSIRO Division of Wildlife and Ecology, Australian Government Publishing Service, Canberra.
Williams, M. (2009). Wild deer in South Australia: position paper for National Deer Workshop. In: McLeod S ed. Proceedings of the national feral deer management workshop, Canberra, November 2005. Canberra, Invasive Animals Cooperative Research Centre. Pp. 66–69.
Wright, J., Varcoe, T. and Toop, S. (2009). Management of deer in Victoria. In: McLeod S. Proceedings of the national feral deer management workshop, Canberra, November 2005. Canberra, Invasive Animals Cooperative Research Centre. Pp. 45–49.