NLRG was formed in 1957 to help in the study of birds in the Lancaster and District Birdwatching Society area. There are currently 12 active ringers. Species currently being studied include: Pied Flycatcher, Bearded Tit, Sand Martin, Twite, Goosander, Oystercatcher and Grey Wagtail. Migration has been studied for 28 years at Heysham. We welcome anyone who wants to observe, help or perhaps wish to become a ringer. Photo: A Heysham-ringed Twite on the Mull of Kintyre (thanks to Eddie Maguire)

Sunday 23 November 2008

How Long do Garden Birds Live?

A recent re-trap of a six year old Long-tailed Tit and a five year old Chaffinch at my feeding station made me trawl our data base to find out if these was our oldest birds of these species. Our record is a Chaffinch which was still going strong at 8 years and 324 days and a Long-tailed Tit 7 years and 287 days.

This made me search for the oldest records we have for other garden birds. The results are as follows

Blue Tit 7 years and 120 days

Long-tailed Tit 7 years and 287 days

Robin 7 years and 95 days

Greenfinch 5 years and 96 days

Wren 4 years 361 days

Blackbird 6 years 270 days

But the real surprise was a Great Tit at 11 years and 97 days! Quite a senior citizen! The British record for Great Tit is 26 days short of 14 years!

Almost all these birds were retraps so still going strong. Of course these are the exceptions. The life expectancy of a newly fledged Great Tit can be measured in months not years. One of the most important aspects of ringing is that it allows the calculation of survival rates. These of course do vary from year to year depending on weather and or food availability and of course predation. But a pair of Great tits can produce 10+ young per year so to keep the population stable only 2 need to survive to breed next year

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