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Satellite imagery paints picture of New Britain's disappearing forest birds

News from BirdLife International

09-1-2008

Analyses of satellite images have revealed for the first time the extent of deforestation occurring on the island of New Britain, Papua New Guinea, indicating that many more bird species are threatened with extinction than previously feared.

An eighth of lowland forest on the island –a stronghold for a number of birds found nowhere else on Earth- disappeared between 1989 and 2000, largely driven by a rapid and uncontrolled expansion in global demand for palm oil.

The findings, published in the journal Biological Conservation [1] mean that the total number of threatened or ‘near threatened’ birds on the island will almost double to 21. [2]

Conservationists are now calling for an effective system to adequately protect the crucial lowland forests that remain on New Britain.

In the paper, scientists from the RSPB (BirdLife in the UK), BirdLife International, Conservation International, an independent consultancy and Institute of Environment and Sustainability, EC JRC, analysed ‘before-and-after’ high resolution images of New Britain, showing that approximately 12% of forest cover was lost between 1989 and 2000, including over 20% of forest under 100 m altitude, with substantial areas cleared for commercial oil palm plantations. [3]

“Examining the satellite images of New Britain, we were struck immediately by the clear and extensive loss of forest in many parts of the island”, explained Dr Graeme Buchanan of the RSPB and lead author of the paper. “Deforestation was particular severe in the flat coastal lowlands.”

The authors of the paper then overlaid the maps of forest loss with known habitat preferences of New Britain’s birds. These analyses suggested that extensive habitat loss will have forced significant declines for 21 of the island’s bird species, bringing some to the edge of extinction.

“By comparing this information against the altitudinal ranges of each of the birds that live in New Britain, we estimated the potential effects on species  – a ‘before and after’ of disappearing habitat, and of disappearing populations”, said Buchanan.

The novel study represents the first time that that the use of satellite imagery (‘remote-sensing’) has been used to determine the likely threat status of a complete set of birds present in a given region or locality.

The technique has potential for use in other places where field-data are lacking in areas that may be too extensive or too difficult to survey on the ground, as is the case on New Britain.

The island of New Britain is a hotbed of rare and unusual bird species, home to 37 endemic (occurring nowhere else on Earth) or ‘restricted-range’ bird species. Species most affected by deforestation on the island are those which cannot tolerate degraded or non-forest habitats, and that only occur in the lowlands. [4]

The paper reports that hardest hit is the strikingly iridescent Bismarck Kingfisher Alcedo websteri –a specialist of lowland forest streams- which lost a fifth of its habitat during the ten year period. [5]

Other birds to suffer include the Green-fronted Hanging-parrot Loriculus tener, which lost 18% of its habitat in the same period.

Southeast Asia’s largely unregulated and expanding palm oil industry –fuelled by increasing global demand- is highlighted as the main factor behind the extensive lowland forest loss on New Britain.

“The findings show that New Britain’s endemic birds are being driven to extinction by our thirst for palm oil, which is widely used in foodstuffs and industry”, said Dr Stuart Butchart, BirdLife’s Global Species Programme Coordinator and co-author of the paper. “After wiping out the lowland forests of Malaysia and Indonesia, companies are now moving eastwards, to New Guinea and Melanesia, where they now threaten a whole new suite of species.”

Based on further analysis of the satellite images, an estimated 320 km2 (11%) of the land cleared had already been converted to plantation, mainly for palm oil. Much of the remainder is likely to be planted up in the next few years: “it is likely that oil palm plantations will continue to increase rapidly: by 2001, oil palm estates at just two sites totalled c.295 km2 with one company planning to expand its plantations on New Britain to 800 km2 by 2014”, the authors assert.

The paper recommends potential areas to designate as protected areas, concluding “there is clearly a pressing need to survey these areas to confirm that they are refuges for New Britain’s endemic fauna, and to ensure their immediate and effective protection”. [6]

Notes:
[1] Using remote sensing to inform conservation status assessment: estimates of recent deforestation rates on New Britain and the impacts upon endemic birds – Buchanan, G.M., Butchart, S.H.M., Dutson, G., Pilgrim, J.D., Steininger, M.K., Bishop, K.D. & Mayaux, P. 2008. Biological Conservation. 141: 56-66 (doi:10.1016/j.biocon.2007.08.023)

[2] BirdLife is the Red List Authority for birds on the IUCN Red List, each year submitting a revised list of species to the IUCN to include in its annual Red List update.

Ten of the bird species on New Britain will be ‘uplisted’ to higher categories of threat on the IUCN Red List next spring, based on the results of the satellite study.

‘Threatened’ species include those listed on the IUCN Red List as Critically Endangered (facing an extremely high risk of extinction in the wild), Endangered (facing a very high risk of extinction in the wild) and Vulnerable (facing a high risk of extinction in the wild). Near Threatened is defined as those species close to qualifying for Vulnerable.

[3] Scientists from the following organisations were involved in the research: BirdLife International, RSPB (BirdLife in the UK), Conservation International, Institute of Environment and Sustainability, EC JRC.

[4] New Britain is crescent-shaped, approximately 600 km (370 miles) along its southeastern coastline, and from 30 to 110 km (20-70 miles) wide, not including a small central peninsula. The island is the 38th largest in the world, with an area of 37,800 km² (14,600 mile²), according to Wikipedia.

The island of New Britain, east of New Guinea, is of very high global conservation importance, and home to 37 endemic or restricted-range bird species.

The island forms part of a high priority Endemic Bird Area (EBA) with New Ireland and satellites which together support 38 endemic bird species. For a factsheet on New Britain with information on habitat types and species present, visit BirdLife’s Data Zone

[5] BirdLife Species Factsheets: Bismarck Kingfisher Alcedo websteri, Green-fronted Hanging-parrot Loriculus tener

[6] This year saw the launch of BirdLife’s Preventing Extinctions initiative, working to save the world’s threatened birds by finding companies and institutions to act as BirdLife Species Champions, funding conservation efforts working on the ground. For more information: BirdLife’s Preventing Extinctions

http://www.birdlife.org/news/pr/2008/01/new_britain.html