南亞鴇( Ardeotis nigriceps )已被列入極危等級(CR)，是受威脅的最高等級。狩獵、人為干擾、棲地流失與破碎讓這種鳥類數量減少到僅剩250隻。
另一個瀕危的物種是巴哈馬黃鸝(Bahama Oriole，Icterus northropi )，也是極危(CR)名單中的新面孔，根據最近的調查，這種黃黑相間的加勒比海鳥類可能僅剩下180隻。
這種黃鸝鳥生長在成熟林地，在椰子樹上築巢。致命的椰子樹黃化病讓巴哈馬黃鸝過去築巢的椰子樹不復存在。黃鸝鳥也受到最近燕八哥( shiny cowbird，Molothrus bonariensis )入侵的威脅，他們會將卵產在別的鳥類的巢內。
坎貝爾島水鴨( Anas nesiotis )則受惠於大規模的滅鼠方案，加上對存活個體的人工養殖，現在該物種已經回到紐西蘭的坎貝爾島，並且在那裡順利繁衍，其受威脅等級也被重新調整成瀕危(EN)。
白頭藪雀( Atlapetes pallidiceps )，由極危(CR)升為瀕危(EN)。
黑被刺嘴鶯( Ramphomicron dorsale )，由少受關注(LC)升至瀕危(EN)。
領海燕( Pterodroma brevipes )，由易危(VU)升至瀕危(EN)。
薩摩亞鶲( Myiagra albiventris )，由易危(VU)降至接近威脅(NT)。
蘇拉塚雉( Megapodius bernsteinii )，由接近威脅(NT)升至易危(VU)。
白頷鷦鷯( Rimator pasquieri )，由少受關注(LC)升至瀕危(EN)。
蛇鷲( Sagittarius serpentarius )，由少受關注(LC)升至易危(VU)。
巾冠兀鷲( Necrosyrtes monachus )，由少受關注(LC)升至瀕危(EN)。
小紅隼( Falco naumanni )，由易危(VU)降至少受關注(LC)。
索科特拉鵟( Buteo socotraensis )是新描述種，被列為易危(VU)等級。
One of the planet's largest species of bird is on the edge of extinction, according to the 2011 IUCN Red List of Threatened Species for Birds, released today by BirdLife International, an IUCN Red List partner.
The Great Indian Bustard, Ardeotis nigriceps, has been uplisted to Critically Endangered, the highest level of threat. Hunting, disturbance, habitat loss and fragmentation have reduced this species to as few as 250 individuals.
Standing a meter (39 inches) in height and weighing in at nearly 15 kg (33 pounds), the Great Indian Bustard was once widespread across the grasslands of India and Pakistan but is now restricted to small and isolated fragments of habitat.
This year's update brings the total number of threatened bird species to 1,253, or 13 percent of the world's total number of bird species.
"In the space of a year, another 13 bird species have moved into the threatened categories," said Jean-Christophe Vié, deputy director, IUCN Global Species Programme.
"Birds provide a window on the rest of nature. They are very useful indicators of ecosystem health. If they are faring badly, then so is wildlife more generally," said Dr. Stuart Butchart, BirdLife's Global Research and Indicators coordinator.
Another species on the brink is the Bahama Oriole, Icterus northropi, also newly listed as Critically Endangered. Recent survey work suggests the population of this black and yellow Caribbean bird could be as low as 180 individuals.
These orioles live in mature woodland, and nest in coconut palms. Lethal yellowing disease of these palms has wiped out nesting trees in areas where the Bahama oriole was previously common but is now absent. The oriole is also threatened by the recent arrival of the shiny cowbird, Molothrus bonariensis, a brood parasite that lays its eggs in other species' nests.
In Africa, the Secretarybird, Sagittarius serpentarius, has been uplisted from Least Concern to Vulnerable. In 2009, this species was assessed as Least Concern due to its "extremely large range" wrote Butchart in Secretarybird's listing in the IUCN Red List of Threatened Species. "Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over 10 years or three generations)."
The Campbell Island teal, Anas nesiotis, has benefitted from a massive programme to eradicate rats, plus captive breeding of remaining individuals. The species has now returned to New Zealand's Campbell Island and the majority of birds are now thriving, resulting in a reclassification of the threat status to Endangered.
Dr. Bennun said, "Birds are so intertwined with human culture all around the world that they present a very visible picture of the state of nature. Good examples abound of how we can save threatened birds. We need to redouble our efforts to do so, otherwise we risk not just losing magnificent creatures like the Great Indian Bustard, but unravelling the whole fabric of our life support systems."
Other regional highlights of the newest bird assessment:
Pale-headed Brush-finch, Atlapetes pallidiceps,, has been downlisted from Critically Endangered to Endangered.
Black-backed Thornbill, Ramphomicron dorsale, has been uplisted from Least Concertn to Endangered.
Collared Petrel, Pterodroma brevipes, has been uplisted from Near Threatened to Endangered.
Samoan Flycatcher, Myiagra albiventris, has been downlisted from Vulnerable to Near Threatened
Sula Megapode, Megapodius bernsteinii, has been uplisted from Near Threatened to Vulnerable
White-throated Wren-babbler, Rimator pasquieri, has been uplisted from Least Concern to Endangered
Secretarybird, Sagittarius serpentarius, has been uplisted from Least Concern to Vulnerable.
Hooded Vulture, Necrosyrtes monachus, has been uplisted from Least Concern to Endangered.
- Europe and the Middle East
Lesser Kestrel, Falco naumanni, has been downlisted from Vulnerable to Least Concern
Socotra Buzzard, Buteo socotraensis, is newly described and has been listed as Vulnerable.