Joyce Fegan: Biodiversity provides evidence of climate change at home

Bewick's swans: This winter there were 'just five or six' of these birds recorded in Ireland. In the 19th century, tens of thousands of them would have wintered here.

A perennial question: When is the official start of spring? In school, we were often told it was February 1 but Met Éireann says it's officially March 1 — and that's meteorologically speaking. There is also the astronomical date, based on the alignment of the sun and the earth, making the start of spring March 22 this year. 

There is also phenological spring, which looks at the growth of plants, flowers, and trees. It is this measure that's showing spring is happening as much as a whole month earlier in Ireland when you compare records from 40-60 years ago. Scientists are linking this jump to climate change as it is temperatures that dictate when leaves unfold and flowers bloom.