Friday, 14 September 2012

Noisy Neighbours

Once hit, never Arctic Tern on the Farnes 

Food supply was excellent this year 

Silver ghost... 

Up close and personal 

Friday 14th September comments: In the latest seabird review, we take a closer look at our ‘noisy neighbours’ the Arctic Terns...

The first Arctic Terns started arriving in Farne waters from mid-April and aerial courtship displays soon followed, with the first eggs discovered on 13th May (an average laying date). The population remained stable on the Farnes with a slight increase on the previous year with 1,866 pairs nesting (an increase of 36 pairs on 2011). The following figures represent the total number of breeding pairs per island, with the bracketed figures representing the breeding totals for the previous season: Inner Farne 1,282 (1,170), Staple 11 (0) and Brownsman 573 (660).

The ranger staff monitored 1,010 nests (representing 55% of the population) which produced 654 fledged young (an overall productivity rate of 0.65). Once again, the highly disturbed courtyard on Inner Farne remained the most productive – the presence of visitors keeping away predatory Gulls, resulting in some excellent returns from that area. In other more exposed areas of the colony (away from the public) predation levels were high. This tactic works well for Arctic Terns, as they prefer to nest near high disturbance areas – something which surprises many people!

Elsewhere the colony within the lighthouse compound on Inner Farne continues to increase in size as the first few pairs nested in 2009 increasing to this years impressive 246 pairs. Overall, food supply was excellent (one of the best in recent years) with breeding success only being limited by the weather, as heavy rain and below average temperatures resulting in small chicks succumbing to the elements.

Overall, it was a difficult year for Arctic Terns, with poor weather at the wrong time of year (June-July) resulting in reduced breeding success although despite this (it could have been a lot worse), as a good number of chicks still went on to fledge.

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