Sunday, April 19, 2015

Macquarie Island wildlife recovering after rabbit eradication

By Fiona Breen
Updated
Seals and king penguins off the coast of Macquarie Island Photo: Seals and king penguins on the beach at Macquarie Island (ABC News: Dave Hudspeth)

After decades of being overrun with feral rabbits, World Heritage-listed Macquarie Island is on its way to returning to the wildlife haven it once was. At Sandy Bay on the east coast, royal penguin colonies are coming down from the steep hillsides, with groups of breeding pairs waddling down a well-worn track to the ocean. It is a precarious route. Along the way hungry petrel seabirds hope to pick off a weak penguin for dinner.

A hut on Macquarie Island is removed by helicopter
 
Photo: Huts used by hunters during the Macquarie Island rabbit eradication program were removed by helicopter. (ABC News: Fiona Breen)
 

It is the penguins' annual trek. "They're heading off to seas to the north-east, near New Zealand, for winter foraging,"

Macquarie Island ranger Chris Howard said.
These penguins have had a successful breeding season, living off shrimp and fish in nearby waters.

But as temperatures recently dropped, so too did their food supplies. So they are headed to relatively warmer waters. "They'll fatten up in warmer seas over winter and return in about October to start breeding again," Mr Howard said.

Just a week ago there were thousands of royal penguins shuffling in their circles, slowly moving round and round to keep warm. Now the colonies are nearly empty. However, there are plenty of king penguins left. "They do leave, but it depends on when they breed, so there is always some king penguins on the island," Mr Howard said.

Closer to Macquarie Island's main base, at the northern end of the island, there are small numbers of gentoo and rockhopper penguins as well. Penguins and seabirds shelter themselves in the island's growing vegetation.

Successful rabbit eradication gives Macquarie a fresh start

Seabird scientist Rachael Aldermann spent most of this trip down the south-west end of the island.
"I've been down on these slopes with some of our field team assessing how the vegetation is recovering since the successful pest eradication, which has been a real threatening process for seabirds on the island," Ms Aldermann said.

Chris Howard
Photo: Macquarie Island Ranger, Chris Howard (ABC News: Dave Hudspeth)
 

Rabbits came to Macquarie Island with sealers in the early 1800s as a source of food. By the 1980s their numbers had exploded. This prompted a massive island rescue mission that included releasing the callici virus into the rabbit population, large-scale bait drops, and teams of hunters and sniffer dogs.

Last year, the eradication program was declared a success. And now that the Macquarie Island pest eradication team's mission is complete, they have left. And there is little evidence they were ever there — just the way they want it. "Within a couple of years the footprints [of us being there] will fade and they will be photos on a hard drive," eradication team manager Peter Preston said. They will, however, be leaving an island in a state of recovery.
 
"I think it's incredible. I came down here in 2010 and I could see rabbits on the hillside and a lot of the damage and now we are still seeing rapid change, with increasing tussock coverage on the hillside, little fungi popping up all over the place, insects, and it's going to just keep going," island ranger Angela Turbett said. 
 
 King penguins and their chicks
 
It is now clean-up time on the island and the extra huts used by hunters and dogs during the eradication program are being removed. Mr Preston said the huts made a great short-term home. "They were great places, in bad weather they were really a very friendly little home to come home to," he said. "They had everything you needed — two bunks, a gas oven, gas heater, plenty of supplies, and a cold porch where you could put your wet gear outside. They made the life of hunters considerably easier."

Tasmanian Parks and Wildlife rangers have been given special permission to keep one of the huts on the island's wild west coast, the last of the shelters used by hunters. "The plan is that researchers into the future, coming through here, will be able to use the hut as a safe refuge whilst they work through here," Mr Howard said. "Typically we're looking at southern petrels, gentoos, a bit of marine resurveying, and the southern elephant seal senses."

***
 Macquarie Island station

Reporting from Macquarie Island

The ABC has followed Macquarie Island's journey from ecological disaster to recovery since 2011, recording this island's transformation along the way. For cameraman Dave Hudspeth and myself it's our second subantarctic adventure, and it's taken some grit and determination to work in such changeable conditions.
One of Macquarie Island's Gentoo penguins

We've had five days on land crisscrossing the mountainous landscape in snow, rain hail and even some sunshine. Every hill climbed has been worth it. We've been mingling with king and royal penguins, sharing beaches with elephant seals and hungry seabirds and experiencing amazing auroras. We've met a passionate group of scientists, rangers, and tradespeople excited about this island's vegetation recovery now the rabbits rats and mice are gone. They're a tough and fit group, appointing themselves as protectors of this World Heritage-listed land in the middle of the Southern Ocean. The journey is coming to an end, we're on the Aurora Australis but we've left 13 hardy expeditioners on the island as caretakers for the winter. It'll be six months before they see anyone else again.
 Royal penguins move to an east coast beach on Macquarie Island

source

No comments: