BTO PUBLISHES VALUABLE NEW RESEARCH ON NOMADIC LIFESTYLE OF SHORT-EARED OWLS

Short-eared owl - a life on the move

THE nomadic lifestyle of the short-eared owl has been underlined by the travels of a bird fitted with a satellite tag while at her nest site in Scotland.

She is now wintering near Oualidia in Morocco having been tagged on June 11 this year on the island of Arran. 

From Scotland via Devon and France to Morocco

The BTO, which is steering  research on the species, this week issued a statement about her travels.

"The bird left Arran to visit Bute and Kintyre from 15-17 July, returning to Arran for 10 days and then moving to mainland Ayrshire on 27 July. 

"She remained here (near Dalmellington) until the end of October, then moved to Devon, where she was present on 8 November, leaving the following evening to head south. 

"With the help of a strong tail wind, she travelled 495 km into France in just six hours - that's an average of 82.5 km/h! 

"She then continued south, crossing the Pyrenees on 13 November and the Strait of Gibraltar on 24 November to reach Morocco."

The BTO’s short-eared owl tracking project aims to find out more about their fine-scale habitat requirements in order to provide advice on how best to create and maintain suitable conditions. 

The trust is also keen to learn more about the species'  migration strategies and connectivity between populations.

The data should prove helpful in providing guidance to policy-makers and land managers.

These tags are solar powered and record the birds’ locations to within an accuracy of a few metres. 

So long as they receive enough light to charge the battery, the tags record precise fixes every three hours (less frequently during dark winters), then relay these to the project scientist, John Calladine.

John Calladine with a tagged bird

So far, the BTO, working with local collaborators, has tracked nine short-eared Owls in Scotland since 2017. 

All have provided detailed information on habitat and landscape use, and some have gone on to show astonishing movements and behaviours which differ markedly both between birds and also by the same bird between years.

A female tagged in Stirlingshire in 2017 overwintered locally, then undertook a wide-ranging exploratory flight within Scotland before settling down to breed again in Perthshire in March 2018. 

Not long after her chicks had hatched she left her mate to continue feeding them and flew to Norway where the tracking data strongly-suggest that she bred for a second time within the same year. 

The tag then tracked her movements to Ireland, Cornwall and Norfolk before recording her final hours as she attempted to migrate back to Norway in spring 2019, sadly perishing in storm close to the Norwegian coast.

The trust aims to tag between three and  five short-eared Owls each year for the next few years.

Illustrations: BTO

A female tagged in Stirling is thought to have  bred in both Scotland and Norway in the same year