Isle of May seabird studies in 2003

• Main Authors: Wilson, L. J., Wanless, S., Harris, M. P., Jones, G.
• Format: Report
• Language: unknown
• Published: JNCC 2004
• Subjects: Zoology; Fulmar; Atlantic puffin; Black-legged Kittiwake; common guillemot; Northern Fulmar; Razorbill
• Online Access: http://nora.nerc.ac.uk/id/eprint/6600/; http://www.jncc.gov.uk/pdf/jncc362_web.pdf

During 2003, weather conditions on the Isle of May, like much of the UK, were considerably warmer and drier than in recent years. Most seabird species experienced a reasonably productive breeding season, with breeding success for all species except common guillemot and razorbill being close to, or above, the long term average. European shag productivity saw its highest value on record and continued the trend of very high breeding success seen during the previous three seasons. Black-legged kittiwakes had their second most productive season since 1990. Breeding success of both northern fulmars and Atlantic puffins was close to the long term average, and similar to 2002. Common guillemot productivity was no higher than in 2002, and was still below the long term average. Razorbill breeding success was well below the long term average and lower than that of 2002. Timing of breeding was earlier for European shags and common guillemots, but normal for northern fulmar, black-legged kittiwake, Atlantic puffin and razorbill. Return rates of colour-ringed European shags, black-legged kittiwake and Atlantic puffins were close to, or above, the long term average, while those for common guillemots and razorbills were slightly lower. As in previous years, lesser sandeels were the predominant prey species for all species, except for guillemots, which mainly brought back clupeids for their chicks. Northern fulmar breeding success (0.44 chicks per pair) was similar to that of 2002, and close to the long term average. European shags had another productive season, with timing of breeding (the first eggs were laid on 23 March) being much earlier than in 2001 and 2002. Breeding success was 1.83 chicks per pair, the highest ever recorded here. As in 2002, return rate was high at 92.7%. Timing of breeding for black-legged kittiwakes was normal, but 15% of birds occupying a site did not start nest building. Those pairs that did complete a nest, however, produced an average of 0.77 chicks per pair. This value is much higher than that ...