Alauda arvensis – EHEDYDD – Breeding resident and passage migrant
|No of tetrads occupied||421 (of 478)|
|Percentage of tetrads||88.1%|
Both Mathew (1894) and Lockley et al. (1949) considered the Skylark to be a common resident. Although still widely distributed it is probably less abundant now. There have been major changes in land management since Mathew’s day, many of which have not suited Skylarks. A Camrose farmer has commented that they are less numerous on his farm than they used to be. He has converted from mixed farming to a large dairy herd with an intensive grazing regime and cultivates long silage paddocks which are not ideal habitat for the species.
The Breeding Birds Survey of 1984-1988 found Skylarks to be sparser on the dairy farms than in Mountains, the St Davids commons and the offshore islands of Skokholm and Skomer. Allowing for this and taking an average density of 15 pairs per tetrad, the total breeding population is probably about 8,000 pairs.
There is a strong diurnal passage towards Ireland from late September to mid- November but no comparable visible spring return movement. This could mean they largely return at night, and they have been seen at lighthouse attractions at the South Bishop in late February and at the Smalls in March. They also migrate at night in the autumn, when casualties occur at the same lighthouses.
Skylarks flock during the mild winters normally experienced in Pembrokeshire, large areas then being devoid of them as they group in single fields or rough patches. Large numbers accumulate in the coastal strip during severe weather when many also pass through towards Ireland; for example, a count of a broad movement was made at Marloes on 26 January 1952 when 300-400 passed west in just 15 minutes (Conder 1954). Should the hard conditions persist many of those that stay may die, sometimes in thousands (Lockley et al. 1949). On Skomer, during hard weather in January 1962, Harris (1962) noted that large numbers of Skylarks were present but suffered little. A year later hundreds of weakened Skylarks were killed and eaten by Carrion Crows at Goodwick during the arctic winter of 1963.