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Roopak Gangadharan
28-05-2010, 10:30 AM
http://news.bbc.co.uk/earth/hi/earth_news/newsid_8702000/8702598.stm


The Alaotra grebe is extinct, according to the latest assessment of the world's rarest birds.

The last known sighting of the bird was in 1985 and experts have now confirmed its demise, killed off by a combination of poaching and predatory fish.

The Malagasy species, which lived in Lake Alaotra, is the first confirmed bird extinction since 2008.

However, fortunes have improved for rare birds such as the Azores bullfinch and Colombian yellow-eared parrot.

No escape

The Alaotra grebe (Tachybaptus rufolavatus) was a medium-sized bird with small wings that inhabited Lake Alaotra and surrounding areas in Madagascar.

Due to its tiny wings, the bird was thought incapable of flying long distances, living a mainly sedentary lifestyle on the lake and in surrounding ponds and highland lakes.

The only known photo of an Alaotra grebe
Twelve Alaotran grebes were sighted at Lake Alaotra in December 1982, and two near Andreba on Lake Alaotra in September 1985.

Some birds with characteristics of the grebe were seen in 1985, 1986 and 1988, but these are thought to be hybrids with another grebe species.

Surveys in 1999 and a visit by experts in 2000 found no individuals, or any grebes belong to the same genus Tachybaptus.

No direct observations of the species have been made since and hopes that the bird might survive were dashed after a recent expedition to nearby Lake Amparihinandriamabavy failed to find any grebes.

Officials have now declared the bird extinct in the latest update to the IUCN Red List of endangered and threatened birds.

The Red List, regarded as the most authoritative assessment of the state of the planet's species, draws on the work of scientists around the globe.

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"No hope now remains for this species. It is another example of how human actions can have unforeseen consequences," says Dr Leon Bennun of Birdlife International, which evaluates the status of rare birds for the IUCN Red List.

The grebe is thought to have been driven to extinction by a combination of factors.

The bird, usually found in pairs, fed almost exclusively on fish in Lake Alaotra, a large brackish lake which had shores once covered in dense papyrus and reeds.

But in recent years, fishermen have covered much of the lake with monofilament nylon gill-nets which can kill diving waterbirds.

These nets were introduced after the grebe had already significantly declined, though they may have killed remaining birds.

Carnivorous fish (Micropterus and Ophiocephalus) introduced into the lake are also thought to have significantly contributed to the grebe's extinction, while the introduction of other invasive mammals, fish and plants likely depleted the grebe's food sources.

Azores bullfinches are faring better
Poaching also reduced its numbers.

Knowing exactly when a species has gone extinct is extremely difficult, as records of sightings can be patchy or unsubstantiated.

Also, comprehensive surveys must be completed to ensure a species does not survive in previously unexplored habitats.

For those reasons, species are often declared extinct many years after they have last been seen.

The last bird species to be confirmed extinct is the Liverpool pigeon (Caloenas maculata), declared extinct in 2008.

However, this Pacific species is known from just two specimens, one of which has been lost. It likely went extinct before Europeans colonised the Pacific.

SOURCES

To view the conservation status of any bird, visit the IUCN Red List
Find out more about BirdLife International's Preventing Extinctions Programme
In 2005, the Thick-billed Ground-dove (Gallicolumba salamonis) was declared extinct, it too known from two specimens, the last caught in 1927.

Other birds declared extinct in the 21st Century include the Hawkins's Rail (Diaphorapteryx hawkinsi), Reunion Shelduck (Alopochen kervazoi) and Kamao (Myadestes myadestinus) among others.

Modern species thought to be extinct, but not yet confirmed, include the Po'ouli (Melamprosops phaeosoma).

The last known survivor of this honeycreeper species died in captivity in 2004, despite huge efforts to rescue it.

Surveys have yet to be done to confirm it no longer survives on the remote highland slopes of Hawaii.

Another species suffering from the impacts of invasive species is the Zapata Rail (Cyanolimnas cerverai) from Cuba.

Yellow-eared parrots have been downgraded
It has been updated to "Critically Endangered" on the latest Red List, under threat from introduced mongooses and exotic catfish.

Only one nest has ever been found of this species.

However the new Red List does highlight some conservation success stories.

The Azores bullfinch (Pyrrhula murina) has been downlisted from "Critically Endangered" to "Endangered" after efforts to restore its habitat.

In Colombia, the Yellow-eared parrot (Ognorrhynchus icterotis) has also benefited from protection of its nest sites and education programmes, leading to its status being downgraded to "Endangered".

Around 190 bird species out of more than 10,000 known are thought to have gone extinct since modern records began

Lakshminarayanan Nataraja
28-05-2010, 10:06 PM
It is strange to note that more ducks are getting extinct. Quite recently in India pink headed duck was declared extinct.

The message is very clear. Our fresh water cycle is terribly disturbed and in years to come it is freightening to even think how we will manage to get clean water to drink.

Our advancements and rat race is set to pay too heavily for us if not we end the race immly..

Thanks for sharing, Roopak.

Sabyasachi Patra
03-06-2010, 01:36 PM
And when there is talk of clean water, one can see that the polluted streams are impacting our wildlife as well. Just see the deformities in the mega fauna ie. tumors, lessions etc.

Also, I am posting the press release issued by BNHS regarding the list of threatened bird species as it is in similar lines.
Sabyasachi

Press Release

List of threatened bird species in India rises to 154
Habitat destruction is primary reason behind decline in bird numbers

Mumbai: Recent studies by BirdLife International and BNHS (Bombay Natural History Society) in India have revealed that the list of threatened bird species in the country has risen from 149 in 2008 to 154. Destruction of habitat is the prime reason for all these disappearing species. According to BirdLife studies in Asia, the condition of Great Slaty Woodpecker has deteriorated from “Least Concern” to “Vulnerable”, while that of Rufous-backed Bunting has deteriorated from “Vulnerable” to “Endangered”.

Commenting on the decline in bird numbers, BNHS director Dr Asad Rahmani said, “It is extremely alarming that almost 13% of world’s birds are either critically endangered, endangered or vulnerable. Great Slaty Woodpecker is an addition from India into the vulnerable category, primarily due to habitat loss. The fact that now 154 bird species from India are threatened, as against 149 last year, is an indicator of further deterioration of the environment.”

Dr Rahmani, who is also a member of the Global Council of BirdLife and Chairman of BirdLife Asia Council added that supposedly common species in India like Nilgiri Blue Robin and White-bellied Blue Robin have been included in the endangered category. Himalayan Quail and Pink-headed Duck are considered extinct in India since they have not been seen for nearly 100 years. But as there is still hope to rediscover these birds, they have been included in the critically endangered category.

BNHS and IBCN (Indian Bird Conservation Network, which was set up by BNHS) have been working on several critically endangered species like Bengal Florican, Jerdon’s Courser, Sociable Lapwing, Forest Owlet and four species of vultures. Dr Rahmani has been working on the Great Indian Bustard for 30 years. This bird, one among the 16 endangered species in India, is very likely to become critically endangered soon, unless concrete steps are taken for the protection of its habitat.

Globally, the picture is no different. BirdLife has announced extinction of Alaotra Grebe in the 2010 IUCN Red List update for birds. This bird was restricted to a tiny area of east Madagascar and it declined rapidly after carnivorous fish and nylon gill-nets were introduced to the lakes in which it lived. “Invasive alien species have caused extinctions around the globe and remain one of the major threats to birds and other biodiversity”, said Dr Leon Bennun, BirdLife International’s Director of Science, Policy and Information.

Other bird species suffering globally include Zapata Rail, a wetland bird from Cuba that is now critically endangered due to the menace of introduced mongooses and exotic catfish and pressure on wetlands. The Great Knot and Far Eastern Curlew are now under serious threat due to drainage of wetlands and pollution. Wattled Curassow and White-bellied Cinclodes from the Americas, Australian Painted Snipe and Kofiau Paradise-kingfisher from the Pacific, Black Crowned-crane and Ludwig’s Bustard from Africa and Corsican Nuthatch from Europe are also seriously under threat. Only a few species like Azores Bullfinch from Europe and Yellow-eared Parrot from Columbia have shown some increase in numbers after they got strict protection.

In light of the alarming situation of several bird species in India, BNHS strongly urges the Government of India to start special programmes for the protection of birds and their habitats. BNHS has identified 466 Important Bird Areas (IBAs) across India, which are crucial bird habitats. At present 200 among them are not officially protected. BNHS feels that all such areas should be protected and the local communities should be involved in such conservation measures in such a way that it becomes a win-win situation for all with a sustainable development model.

Sr Species Category
1 Himalayan Quail Ophrysia superciliosa CR
2 Pink-headed Duck Rhodonessa caryophyllacea CR
3 White-bellied Heron Ardea insignis CR
4 Christmas Island Frigatebird Fregata andrewsi CR
5 White-rumped Vulture Gyps bengalensis CR
6 Indian Vulture Gyps indicus CR
7 Slender-billed Vulture Gyps tenuirostris CR
8 Red-headed Vulture Sarcogyps calvus CR
9 Bengal Florican Houbaropsis bengalensis CR
10 Siberian Crane Grus leucogeranus CR
11 Sociable Lapwing Vanellus gregarius CR
12 Spoon-billed Sandpiper Eurynorhynchus pygmeus CR
13 Jerdon's Courser Rhinoptilus bitorquatus CR
14 Forest Owlet Heteroglaux blewitti CR
15 Large-billed Reed-warbler Acrocephalus orinus DD
16 Sillem's Mountain-finch Leucosticte sillemi DD
17 Green Peafowl Pavo muticus EN
18 Red-breasted Goose Branta ruficollis EN
19 White-winged Duck Cairina scutulata EN
20 Baer's Pochard Aythya baeri EN
21 White-headed Duck Oxyura leucocephala EN
22 Oriental Stork Ciconia boyciana EN
23 Greater Adjutant Leptoptilos dubius EN
24 Egyptian Vulture Neophron percnopterus EN
25 Great Indian Bustard Ardeotis nigriceps EN
26 Lesser Florican Sypheotides indicus EN
27 Masked Finfoot Heliopais personatus EN
28 Spotted Greenshank Tringa guttifer EN
29 Narcondam Hornbill Aceros narcondami EN
30 Black-chinned Laughingthrush Strophocincla cachinnans EN
31 Nilgiri Blue Robin Myiomela major EN
32 White-bellied Blue Robin Myiomela albiventris EN
33 Japanese Quail Coturnix japonica NT
34 White-cheeked Partridge Arborophila atrogularis NT
35 Satyr Tragopan Tragopan satyra NT
36 Tibetan Eared-pheasant Crossoptilon harmani NT
37 Hume's Pheasant Syrmaticus humiae NT
38 Falcated Duck Anas falcata NT
39 Ferruginous Duck Aythya nyroca NT
40 Lesser Flamingo Phoeniconaias minor NT
41 Painted Stork Mycteria leucocephala NT
42 Black-necked Stork Ephippiorhynchus asiaticus NT
43 Black-headed Ibis Threskiornis melanocephalus NT
44 Spot-billed Pelican Pelecanus philippensis NT
45 Oriental Darter Anhinga melanogaster NT
46 Laggar Falcon Falco jugger NT
47 Red Kite Milvus milvus NT
48 Lesser Fish-eagle Ichthyophaga humilis NT
49 Grey-headed Fish-eagle Ichthyophaga ichthyaetus NT
50 Cinereous Vulture Aegypius monachus NT
51 South Nicobar Serpent-eagle Spilornis klossi NT
52 Andaman Serpent-eagle Spilornis elgini NT
53 Pallid Harrier Circus macrourus NT
54 Little Bustard Tetrax tetrax NT
55 Andaman Crake Rallina canningi NT
56 Beach Thick-knee Esacus giganteus NT
57 Great Snipe Gallinago media NT
58 Asian Dowitcher Limnodromus semipalmatus NT
59 Black-tailed Godwit Limosa limosa NT
60 Eurasian Curlew Numenius arquata NT
61 Buff-breasted Sandpiper Tryngites subruficollis NT
62 Black-bellied Tern Sterna acuticauda NT
63 Andaman Wood-pigeon Columba palumboides NT
64 Andaman Cuckoo-dove Macropygia rufipennis NT
65 Nicobar igeon Caloenas nicobarica NT
66 Nicobar Parakeet Psittacula caniceps NT
67 Long-tailed Parakeet Psittacula longicauda NT
68 Andaman Scops-owl Otus balli NT
69 Andaman Hawk-owl Ninox affinis NT
70 Ward's Trogon Harpactes wardi NT
71 European Roller Coracias garrulus NT
72 Brown-winged Kingfisher Pelargopsis amauroptera NT
73 Blyth's Kingfisher Alcedo hercules NT
74 Austen's Brown Hornbill Anorrhinus austeni NT
75 Malabar Pied Hornbill Anthracoceros coronatus NT
76 Great Hornbill Buceros bicornis NT
77 Yellow-rumped Honeyguide Indicator xanthonotus NT
78 Andaman Woodpecker Dryocopus hodgei NT
79 Mangrove Pitta Pitta megarhyncha NT
80 Andaman Drongo Dicrurus andamanensis NT
81 Andaman Treepie Dendrocitta bayleyi NT
82 Rufous-vented Prinia Prinia burnesii NT
83 Grey-headed Bulbul Pycnonotus priocephalus NT
84 Nicobar Bulbul Hypsipetes nicobariensis NT
85 Rufous-rumped Grassbird Graminicola bengalensis NT
86 Long-billed Bush-warbler Bradypterus major NT
87 Tytler's Leaf-warbler Phylloscopus tytleri NT
88 Rufous-throated Wren-babbler Spelaeornis caudatus NT
89 Long-tailed Wren-babbler Spelaeornis chocolatinus NT
90 Blackish-breasted Babbler Sphenocichla humei NT
91 Chevron-breasted Babbler Sphenocichla roberti NT
92 Giant Babax Babax waddelli NT
93 Chestnut-backed Laughingthrush Garrulax nuchalis NT
94 Rusty-bellied Shortwing Brachypteryx hyperythra NT
95 Firethroat Luscinia pectardens NT
96 Black-and-rufous Flycatcher Ficedula nigrorufa NT
97 Nilgiri Flycatcher Eumyias albicaudatus NT
98 Nilgiri Pipit Anthus nilghiriensis NT
99 Nicobar Megapode Megapodius nicobariensis VU
100 Swamp Francolin Francolinus gularis VU
101 Manipur Bush-quail Perdicula manipurensis VU
102 Chestnut-breasted Partridge Arborophila mandellii VU
103 Western Tragopan Tragopan melanocephalus VU
104 Blyth's Tragopan Tragopan blythii VU
105 Sclater's Monal Lophophorus sclateri VU
106 Cheer Pheasant Catreus wallichi VU
107 Lesser White-fronted Goose Anser erythropus VU
108 Baikal Teal Anas formosa VU
109 Marbled Teal Marmaronetta angustirostris VU
110 Lesser Adjutant Leptoptilos javanicus VU
111 Dalmatian Pelican Pelecanus crispus VU
112 Socotra Cormorant Phalacrocorax nigrogularis VU
113 Lesser Kestrel Falco naumanni VU
114 Saker Falcon Falco cherrug VU
115 Pallas's Fish-eagle Haliaeetus leucoryphus VU
116 Nicobar Sparrowhawk Accipiter butleri VU
117 Indian Spotted Eagle Aquila hastata VU
118 Greater Spotted Eagle Aquila clanga VU
119 Eastern Imperial Eagle Aquila heliaca VU
120 Houbara Bustard Chlamydotis undulata VU
121 Sarus Crane Grus antigone VU
122 Hooded Crane Grus monacha VU
123 Black-necked Crane Grus nigricollis VU
124 Wood Snipe Gallinago nemoricola VU
125 Great Knot Calidris tenuirostris VU
126 Indian Skimmer Rynchops albicollis VU
127 Pale-backed Pigeon Columba eversmanni VU
128 Nilgiri Wood-pigeon Columba elphinstonii VU
129 Pale-capped Pigeon Columba punicea VU
130 Red-faced Malkoha Phaenicophaeus pyrrhocephalus VU
131 Dark-rumped Swift Apus acuticauda VU
132 Rufous-necked Hornbill Aceros nipalensis VU
133 Great Slaty Woodpecker Mulleripicus pulverulentus VU
134 White-naped Tit Parus nuchalis VU
135 Grey-crowned Prinia Prinia cinereocapilla VU
136 Yellow-throated Bulbul Pycnonotus xantholaemus VU
137 Bristled Grassbird Chaetornis striata VU
138 Broad-tailed Grassbird Schoenicola platyurus VU
139 Marsh Babbler Pellorneum palustre VU
140 Rusty-throated Wren-babbler Spelaeornis badeigularis VU
141 Tawny-breasted Wren-babbler Spelaeornis longicaudatus VU
142 Snowy-throated Babbler Stachyris oglei VU
143 Jerdon's Babbler Chrysomma altirostre VU
144 Slender-billed Babbler Turdoides longirostris VU
145 Bugun Liocichla Liocichla bugunorum VU
146 Black-breasted Parrotbill Paradoxornis flavirostris VU
147 Beautiful Nuthatch Sitta formosa VU
148 Grey-sided Thrush Turdus feae VU
149 White-browed Bushchat Saxicola macrorhynchus VU
150 White-throated Bushchat Saxicola insignis VU
151 Kashmir Flycatcher Ficedula subrubra VU
152 Yellow Weaver Ploceus megarhynchus VU
153 Green Avadavat Amandava formosa VU
154 Yellow-breasted Bunting Emberiza aureola VU