Global warming driving migration of species in India

Rising temperatures are forcing a huge, untold number of species to move their homes northward or climb to higher altitudes, says an alarming study.

Global warming and changing rainfall patterns have resulted in shifts or extensions in species' range in every terrain, region and ecosystem in India, the findings showed.

"If it is indicative of a wider unfolding process related to climate change, it would suggest that a staggering number of species in India are moving home," said lead study author Nagraj Adve, member of India Climate Justice Collective - a group of social movements for climate justice.

"This would adversely affect human habitat as well," Adve added.

As the globe warms, species are moving away from rising temperatures to places with temperatures are more suited to them.

The other causes driving the migration of species could be changing rain patterns and the availability of food.

While a number of state action plans on climate change and significant official reports largely discuss this process in shifts or extensions in species' range as something that will happen only in the future; this study demonstrates that it is already happening.

"To the best of my knowledge, such an overview has not been done for India before, and it should, ideally, influence the way that climate change is thought about in this country," Adve maintained.

Indicating how such shifts in the geographical location of species could affect human lives, Adve pointed out that major fish species, crucial to diets and incomes, are moving north off both coasts of India because the ocean waters have been getting warmer.

Sea surface temperature over 1967-2007 has increased by 0.15 degrees Celsius every decade along the western coast.

Oil sardines were not present at all off the south-east coast until the mid-1980s, but have spread there in a major way since the 1990s.

Mackerel has become more prominent off the east coast as its range too has moved, from Andhra Pradesh to parts of waters off southern Bengal.

The same northward move has also happened for mackerel off India's west coast.

"These shifts or extensions in range are also occurring in India's rivers as their waters warm," Adve stressed.

The most well-known example of species creeping higher could be the case of apples in Himachal Pradesh.

"With fewer days of freezing weather at 1,500 metres, apples are now flourishing only at altitudes of 2,200-3,000 metres," Adve maintained.

It involved a reading of nearly all the 22 state action plans on climate change (SAPCCs) drafted and in the public domain thus far, besides other studies, a few interviews and personal conversations.

The study appeared in the journal Economic and Political Weekly.