Marsh Harrier - Status

Circus aeruginosus

Scarce passage migrant, winter visitor and former breeder.

The Marsh Harrier breeds throughout the Western Palearctic, wintering southwards as far as Africa but it is resident in some areas.

Said to be formerly a common resident in Pembrokeshire, it had become a rare visitor by the time of Mathew (1894). How rare can be judged by there being only eight recorded occurrences between 1880 and 1941. Eighteen individuals were noted between 1942 and 1980, an increase that cannot be entirely due to a growth in the number of active observers.

From a single pair in 1971, the British breeding population increased by about 20 % per year to reach a minimum of 363 pairs by 2005. Although Pembrokeshire is peripheral to the main breeding area in eastern England and the species remained scarce in the county, its frequency of occurrence increased during the British population expansion.

Pembrokeshire: birds per annum, 1982 – 2011.

 

A pair summered in both 2010 and 2011 but breeding was not proven.

Graham Rees

(Covers records up to and including 2011)