Alarm bells jangling on future of Scotland's small population of breeding choughs

Chough - a restricted genes pool  is thought to be undermining overall fertility of Scottish population 

IN-breeding has been identified as a key threat to Scotland's last remaining choughs - the 50 or so pairs that survive on the two  islands of Islay and Colonsay.

Parasites and lack of natural food are also implicated in the decline according to a report published earlier this week by the BTO and Nature.

Would introducing captive-bred choughs from other populations solve the genetics problem?

Not necessarily so says the report, authored by David Norfolk and Gavin Siriwardena.  

"There is no guarantee that captive-bird releases will succeed in adding to the gene pool

"Released birds may not interbreed with the existing population - there is evidence that this was the case with such a project in Cornwall."

The report says there is a need for research collaboration with Irish colleagues to establish if lessons are to be learned from a similar breeding range contraction in Donegal - home to the nearest chough  population to the ones in Scotland.

It is thought this could have "significant implications" for naturally dispersing Irish birds that represent potential natural Scottish colonists.

As "stepping stones" between Islay and established populations on the Isle of Man and in Ireland, it earmarks Kintyre, Arran, Galloway or coastal Northern Ireland as potential options for introduction initiatives.

                                             

What can be done? A 'parliament' of choughs - photo NatureScot