15 September 2010

New Whimbrel longevity record

Allan Perkins writes:
This summer I spent 3 months on Fetlar, Shetland, studying the breeding success of Whimbrel to help investigate their 'recent' declines. Previous studies by Murray Grant on Fetlar and Unst in the 1980s had involved catching and colour-ringing adult Whimbrel, to monitor brood survival and returning rates of adults from their tropical wintering grounds in subsequent breeding seasons. During 1986-88, 97 Whimbrel were colour-ringed and of those the returning rates were high - c. 89% seen the year after ringing - and most birds returned to breed at the same site used in the previous year. Sightings of some of these birds on Fetlar continued up until the mid-1990s, but none had been recorded since then.

It was on 9 May, this year when I first saw one of these colour ringed birds feeding on the short cliff-top turf of Strandburgh Ness, at the extreme northeast tip of Fetlar. Frustratingly it wasn't until 31 May that I managed to get good views of the colour ring combination and amazingly it was a bird ringed in the 1980s.

The bird was identified as EK92102, ringed as an adult breeding on Fetlar on 1 June 1986, and sexed as a male from subsequent observations. Given that Whimbrels do not normally start to breed until they are two or three years old, this bird must be at least 26 years old, making it the oldest known Whimbrel in the world! This surpasses the previous longevity record of 16 years, held by a Whimbrel ringed as a chick on Mainland Shetland in June 1979 and shot in northern France in August 1995.

EK92102 was last recorded in 1995, but it seems likely that it had been returning, undetected, to Fetlar each year since then. Maybe it will return again next year for potentially its 26th breeding season.

Thanks to Allan for letting us know about this bird and also to Murray Grant for the lower photo.

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