Chocking cities, receding glaciers, drying rivers and sinking islands are the known consequences of global warming. But climate change could ring the death knell for at least 400 types of birds in the next four decades.
Even under the most optimistic scenarios, the future of at least 400 bird species are in danger due to drastic reductions in natural habitat, the scientists have warned. The effects are expected to be visible by 2050.
If things continue more or less in the same fashion, then over the next hundred years, 950 to 1,800 bird species may become endangered or even driven to extinction by climate change and habitat destruction, they said in a research published in the journal, Public Library of Science: Biology on Tuesday. 
Most of these birds are currently not under the shadow of extinction.
Carried out by researchers from University of California, San Diego and Princeton University, the study probably is one the first global assessment of how climate change and habitat destruction may impact the future of birds. Currently there are 8,750 bird species.
Climate change and deforestation have already led to the extinction of many vertebrate animals in the recent decades. But the loss of diversity appears to be accelerating. The most visible consequences will be seen in the Scandinavian countries, Alaska, north of Canada and vast swaths of northern Russia.
What will happen to the Indian birds? Though much research has not been done on this, there are indications of birds shifting their natural habitat possibly on account of temperature change.
Studies carried out by Mumbai’s Bombay Natural History Society (BNHS) in the Kodaikanal hills shows that birds, which were seen at lower elevation in the 1970s, have now moved upwards, BNHS scientist Dr Asad Rahmani told Deccan Herald.
Asserting the need for more research on the topic, he said climate change and deforestation could well have profound impacts on the migratory birds. “They require rest and refuelling during their journeys. If the forests are destroyed where they will take rest?” he asked. 
"Dramatic levels of deforestation and land conversion are projected to continue or even increase in the tropics. There, the birds are diverse and tend to have small ranges, making them vulnerable to extinction,” said Dr Walter Jetz from the University of California.
The US researchers made the estimate after integrating future projections on global warming, agricultural expansion and human population growth with geographical distribution of existing 8,750 bird species.