• When here in the Outer Hebrides and looking at a bird, have you ever wondered how rare it is? The status of all species can vary enormously from island to island. How rare is Shoveler on Barra, has Stock Dove been seen on Harris, does Dotterel occur on Benbecula in the autumn, and how common is Blue Tit on North Uist? Well, fret no longer! The Status and Distribution of birds here on the Outer Hebrides has been completely updated and summarised for every species and each of the main islands and outliers. Available as an online resource at https://status.outerhebrides-birdreports.org/ or via our shop

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Decline of Leach’s Storm Petrels at the largest colonies in the northeast Atlantic

Hawkeye

Eyes and Ears Everywhere
The latest study of Leach's Petrel on St Kilda indicate and very worrying decline of 68% between 2000 and 2019.

Leach’s Storm Petrel Hydrobates leucorhous has undergone substantial population declines at North Atlantic colonies over recent decades, but censusing the species is challenging because it nests in burrows and is only active at colonies at night. Acoustic playback surveys allow birds present in nest sites to be detected when they respond to recordings of vocalisations. However, not all birds respond to playback on every occasion, response rate is likely to decline with increasing distance between the bird and the playback location, and the observer may not detect all responses. As a result, various analysis methods have been developed to measure and correct for these imperfect response and detection probabilities. We applied two classes of methods (calibration plot and hierarchical distance sampling) to acoustic survey data from the two largest colonies of breeding Leach’s Storm Petrels in the northeast Atlantic: the St Kilda archipelago off the coast of northwest Scotland, and the island of Elliðaey in the Vestmannaeyjar archipelago off the southwest of Iceland. Our results indicate an overall decline of 68% for the St Kilda archipelago between 2000 and 2019, with a current best estimate of ~8,900 (95% CI: 7,800–10,100) pairs.

The full article and links to the open access report can be found here
 
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