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Welsh Ramsey island bird news


This video from Wales is called RSPB Ramsey Island – why is it special?

From Wales Online:

Ramsey Island conservation staff serenade Manx Shearwaters as part of population survey

20:43, 1 July 2015

By Liz Day

It is thought that Pembrokeshire‘s three islands are home to more than 50% of the world’s population of Manx Shearwater

Conservation staff on an important island nature reserve in West Wales are spending their days serenading seabirds as part of a population survey.

Wardens on Ramsey Island in Pembrokeshire lower an MP3 player into each burrow and play a recording of a duetting pair of Manx Shearwaters, encouraging the birds inside to call back.

Site manager Greg Morgan said: “This is the only way to accurately survey a species that spends most of its life either at sea or underground.

“We play a short burst of a recording and listen for a response. At this time of year, the birds are incubating eggs, so you have the best chance of getting a response because at least one of the pair should be home by day.”

Success story

Greg, who has counted thousands of burrows on the island, is accompanied by his sheepdog Dewi.

“He loves Shearwater surveys, as he can sniff them out long before I get to the burrow,” he said.

“He usually lies down outside a burrow to tell me if it’s occupied or not. He is very well trained and it’s not unusual for dogs to be used to for seabird surveys.”

Greg describes Manx Shearwaters, which have amber conservation status, as the island’s biggest “success story”.

When the RSPB took over Ramsey in 1992, it was full of rats that arrived on shipwrecks in the 1800s and nearly wiped out the species by eating eggs and chicks.

Puffins had become extinct on the island and a survey in 1998 revealed there were just 850 pairs of Manx Shearwaters.

Last year, volunteers on the island installed a puffin sound system and planted decoys in an attempt to lure the distinctive birds to breed on the island, so far without success.

Healthy bird populations

Rats were eradicated from the island in 1999 and although Puffins have not been reintroduced, the population of Manx Shearwaters has rocketed. The most recent population census, carried out in 2012, recorded 3,800 pairs.

It is thought that Pembrokeshire’s three islands – Ramsey, Skomer and Skokholm – are home to more than 50% of the world’s Manx Shearwaters. Skomer is home to 300,000 pairs, while Skokholm has 45,000 pairs.

Greg and his wife Lisa, the island warden, carried out the last full population census in 2012 and between them counted more than 12,000 burrows.

The next full census is due to take place next summer and the wardens are hoping the population will have continue to grow.

“Fingers crossed our next survey will see the population go from strength to strength,” said Greg.

“We have no reason to think that the number will not have increased again. There is plenty of habitat here and the island is still rat-free.”

Migration monitored

To ensure that no rats access the island, there is a quarantine process for visitors and all supplies are inspected before arriving.

Other surveys carried out this year have revealed there are currently 4,400 Guillemots on Ramsey – the highest number ever recorded. There are also 1,200 Razorbills.

“This number is down slightly on previous years, but Razorbills are one of the species hardest hit by the storms in 2013, so it is not surprising,” explained Greg.

Later this month, he will attach data loggers to the Manx Shearwaters to monitor their migration to South America.

The birds leave their nest sites in July to migrate 7,000 miles to Argentina where they spend the winter before returning in late February and March.

For more informations, see rspb.org.uk/ramseyisland.

Good bird news from Wales


This video is called Skomer Island, June 2013.

From the Skomer Island Blog in Wales:

Wednesday, 1 July 2015

Seabirds doing well on Skomer

Skomer’s seabird counts have come to an end for 2015 and we’re pleased to say it’s good news. Most of our seabirds appear to be doing very well with record counts of Puffins and the highest counts of Guillemots and Razorbills since modern records began. The graphs show that there have been ups and downs but things haven’t looked this good for a while.

After a good year for gulls last year, it seems that things are back to a slow decline in breeding numbers. Our once 20,000 strong Lesser Black-backed Gull [colony] is now down to around 8,000 pairs and Herring Gulls are also clearly having a hard time of it. But it’s not all bad news. Great Black-backed Gulls, however, are doing well with 123 pairs breeding around the island this year. Kittiwakes also, which are struggling in other areas of Britain, are doing well (or perhaps ‘less badly’ is a better term) with an increase of 4% from 1,488 nests in 2014 to 1,546 in 2015.

Fulmars are holding their own and this years count was only 28 different from last years with 584 occupied sites. Counting the Manx Shearwaters is a little more of a challenge but signs from this year’s census show that the population remains healthy.

In terms of coming to see the wonderful assemblages of seabirds on Skomer, July remains a good month to visit. Guillemot and Razorbills chicks, known as ‘jumplings’, because of the fact that they jump off the cliffs before they can even fly properly, are most obvious as they grow and prepare to leave. The Puffins are furiously feeding young in burrows and soon the ‘pufflings’ will be popping out to stretch their wings before leaving under the cover of darkness. Other birds are more leisurely in their breeding cycle. Fulmars and Kittiwakes are either still sitting on eggs or have small chicks and gull chicks will be in evidence right through July and August.

Ed
(Skomer Warden)

Australian fur seals, new research


This video is called The Life of Australian Fur Seals, Arctocephalus pusillus doriferus, Montague Island, 2011.

From Deakin University in Australia:

July 2, 2015

Humans once hunted them, but may now hold key to fur seal survival

Oil rigs and artificial reefs are often given a bad rap for their environmental impact but they may be playing a vital role in feeding one of Australia’s largest sea creatures, still recovering from centuries of hunting by humans, new research led by Deakin scientists has found.

Researchers from Deakin’s Centre for Integrative Ecology within the School of Life and Environmental Sciences teamed up with National Geographic, the University of Tasmania and University of California Santa Cruz to investigate the feeding behaviour of the Australian fur seals in Bass Strait.

Associate Professor John Arnould said some seals carrying the National Geographic “crittercams” revealed they and other individuals congregated around human-made structures which act as artificial reefs attracting fish.

“These findings mean that man-made structures such as pipelines, cable routes, wells and shipwrecks could play a vital role in helping to improve the recovery rates of our fur seals,” he said.

“The Australian fur seal population is increasing at just two per cent a year and still sit at population levels below 60 per cent of what it was before the commercial sealing era in the 18th and 19th centuries.”

The researchers tracked the foraging patterns of 36 Australian fur seals from Kanowna Island in Bass Strait, using GPS loggers and dive recorders.

The research is published today in the latest edition of science journal PLOS One.

“While we know fish congregate around these structures, scientists don’t know a lot about their use by marine mammals and we were surprised at first to find the Australian fur seals were going to these area[s],” Associate Professor Arnould said.

“We found that 72% of the 36 seals we tracked spent time around the man-made structures, with pipelines and cable routes being the most frequented. More than a third of animals foraged near more than one type of structure.”

Associate Professor Arnould said man-made changes to natural habitats could often have negative effects on animals which lived in the regions surrounding them, including a reduction in foraging habitat, breeding sites and refuge from predators.

“Some species, however, can adapt to, and even benefit from, changes to their habitats,” he said.

“Indeed, man-made structures can provide a range of benefits for some species, from predator avoidance, thermoregulation, and breeding sites, to acting as important foraging areas.”

Associate Professor Arnould said seals and sea lions around the world had experienced variable rates of population recovery since the end of the sealing era.

“We have seen species that feed close to the surface have experienced rapid growth in numbers, populations of species that feed on the ocean floor, such as the Australian fur seal, have increased very slowly, are stable or in decline,” he said.

“It has been suggested that the low population recovery rates of these species could be due to them hunting in environments which for decades have been the focus of commercial fisheries using bottom trawlers that disrupt the habitat and remove the larger size-classes of species that the seals depend on for food.

“The Australian fur seal (Arctocephalus pusillus doriferus) feeds exclusively on the sea floor of the continental shelf on a wide variety of fish, octopus and squid species.”

Associate Professor Arnould said all but one of the Australian fur seal’s breeding colonies occurred on islands within Bass Strait, between the Australian mainland and Tasmania, which has an average depth of 60 metres and is considered to be a region of low food availability for marine predators.

“Therefore, structures like oil and gas rigs and pipelines that occur on the relatively featureless sea floor could provide a valuable prey habitat and promote foraging success for the species,” he said.

Explore further: Fur seal population bounces back while sea lions struggle