Albatross Petrel Watch On Remote Islands by Tim Roberts and Emily Mowat, ecologist at Eco Logical Australia
World Migratory Bird Day this month raises the perennial question of how to preserve the breeding grounds of these birds that roam the world and fly the sea. When the nesting preference is an island, the question of elimination of introduced predators and exotics becomes top of mind for both bird-lovers and conservation ecologists. History is full of examples of where the introduction of an exotic species has led to disastrous consequences for the local flora and fauna. Think about our huge island - the rabbit, the fox, and the cane toad to name but a few. For the remote and much smaller islands of the world read rats, mice, cats, goats and rabbits for the culprits that through their prolific breeding and lack of predators have wreaked devastation on both the landscape and also the endemic wildlife.
From 1810 with the advent of fur seal, harvesting the ecology of Macquarie Island was affected. First by rats and mice, then by the cats introduced to control the rodents, then by rabbits causing damage to the vegetation. In 2000, the last of the nearly 2,500 cats were culled in an effort to save the seabirds, and the rabbit and rat population soared. Finally, at a cost of $24million dollars the island was officially declared pest-free in 2014.
On the 31st of May Newcastle two dedicated ecologists, Emily Mowat and Susanne Callaghan speak publicly of successful island pest eradication projects aimed at re-establishing albatross, petrel and other seabird colonies on Macquarie and Broughton Islands respectively. Two good news stories indeed.
It is another story on Lord Howe Island where debate has raged furiously for the last 17 years over plans to eliminate the rats plaguing the island. Taken alongside the brumby debate of the Snowys and the deer debate in the Royal National Park we are reminded once again that social licence is key to successful conservation outcomes.
A capacity crowd of 80 people came to hear Emily Mowat and Susanne Callaghan talk about their seabird surveys on islands near and far at the joint Hunter Environmental Institute and Tom Farrell Institute FREE Seminar that was held on Wednesday 30th May 2018 5:30 til 7:00 at NewSpace Room X502 (Cnr Hunter and Auckland Sts Newcastle).
EMILY MOWAT is a fauna ecologist at Eco Logical Australia, has just returned from a year working as part of the Albatross and Giant Petrel Program on subantarctic Macquarie Island collecting data on the breeding success and population trends of four albatross and two giant petrel species. Emily is passionate about wildlife conservation and management and has worked or volunteered on a wide range of projects in Australia and New Zealand, with a particular focus on birds.
SUSANNE CALLAGHAN is a Ranger with NPWS, and has worked extensively on the ecology of the Broughton Group of offshore islands: including coordinating seabird surveys resulting in the discovery of the threatened Gould’s Petrel on Broughton Island; the successful eradication of rabbits, black rats and house mice off the Broughton Group of islands; and co-ordinating Green and Golden Bell Frog surveys which has resulted in the development of a draft site-specific Plan of Management for the species.
For more information...
Presentations by Emily and Susanne both echoed similar themes of the effect of past exploitation, invasive species, and present day pressures on two different islands.
Emily shared her scientific wonder and excitement for working as a volunteer on Macquarie Island. She told us about the several types of albatrosses and the Giant Petrel that she observed and recorded. Macquarie Island this exemplar of a remote location, and challenging topography, with a legacy of human exploitation combined with invasive rabbits, cats, rats, and mice.
Macquarie Island (affectionately known as Macca) has been recently declared pest free and Emily taught us of some of the challenges involved in this great success. Whereas numbers of the Sooty Albatross and smaller colonies of the Black-browed Albatross and Grey-headed Albatross appear to be recovering, the Wandering Albatross numbers remain critically low, with fewer than 10 breeding pairs remaining. Innovative ways of attracting the Wandering Albatross are being deployed using decoy dummies.
Susanne gave us an insight into restoration and rehabilitation of Broughton island. Broughton island is the largest in a group of islands just offshore north of Port Stephens and is part of the Myall Lakes National Park.
We learnt of the history of the human occupation and use of Broughton Island, and their effect on the natural environment, from the traditional custodians, the Worimi, to sailors and fishermen, and, more recently, tourists. Interestingly, government actions and regulations, since the mid nineteenth century, have delivered a fair degree of protection for the Broughton group of Islands. The government’s motives included preserving a fresh water resource for distressed sailors, as well as as a reserve protecting bird diversity.
Broughton Island, compared to its relatively inaccessible neighbouring islands, has suffered greatly from introduced pests and weeds. Weed control is an ongoing battle on the island with Bitou Bush infestations being tackled by NWPS.
The most damaging pests were rabbits and rats. The rats, it is believed, came with fishing boats, and predate on eggs and chicks in birds nests and burrows. The rabbits were deliberately introduced in the early 1900s as part of a Myxomatosis virus research program. The program was a disaster and they flourished on the island causing significant damage.
A controlled release of the Calicivirus combined with an island wide aerial baiting program for the eradication of rats and rabbits was undertaken in 2009. The program was a resounding success with the island being declared pest free two years later. Significant regrowth of native plants has occurred where rabbits denuded areas, and now approximately 55,000 breeding pairs of Wedge-tailed Shearwaters (Mutton Birds) are nesting on the island.
The Gould’s Petrel and White-Faced Storm Petrel are yet to return to the island in significant numbers, but are being enticed back with nesting boxes and nightly bird-calls on speakers during the nesting season. What this space!