Results from the ringings
History of ringing results
At first the yearly numbers of ringings increased slowly. It was
not until the 1930's that yearly totals of over 10,000 individuals
were reached, while the total amount of 100,000 ringings was reached
in 1939. With the war the number of ringings plunged, as ringers found
themselves in a different position. During the last twenty years 180,000
- 260,000 birds per year have been ringed in Finland. Of these, nestlings
form some 40%.
Shortly after the wars the enthusiasm for ringing grew at a rapid
rate with the one million ringed birds limit being exceeded in 1966,
three million in 1978 and five in June 1988. In all, over 8.8 million
birds have been marked with an individual ring in Finland between
1913 and 2004. In the statistics for the entire period the most commonly
ringed birds are: the Great Tit, the Pied Flycatcher, the Willow Warbler,
the Goldcrest, the Blue Tit, the Robin, the Black-headed Gull, the Sedge Warbler, the Redpoll and the Barn Swallow.
The rather large variation between different years in respect to
the number of ringings is during recent years due to the breeding
success, the varying occurrence of irruptive species, the unstable
manning situation at bird observatories and changes in the activity
of ringers, whereby old projects have died out and new ones been born
Ring recoveries
In 2004, the Ringing Centre processed a total of 48,530 recovery
and recapture reports of Finnish rings. The grand total of recoveries
filed in the database for the years 1913-2004 was over 875,000 at
the end of 2004.
A large part of the recoveries consists of ordinary, "less interesting"
retraps from the same place within a few days. Thus, when annual statistics
are calculated only those recoveries that fulfil any of the following
criteria are accepted:
- The bird was found dead (dead nestlings excluded) or
- The bird was alive but had moved at least 10 km from the ringing
site, or from the previous "accepted" retrap place.
- The bird was alive at the same site as before, but the time elapsed
from the ringing, or from the previous "accepted" sighting,
was at least three months.
Using the method mentioned above makes the number of "interesting"
recoveries 19,824 in 2004, while the total accumulation for 1913-2004
is almost 410,000. These numbers best describe the amount of recoveries
suitable for most analyses.
The majority of recoveries of birds ringed in Finland come from Finland.
Some 20% of the recoveries defined as "interesting" are
reported from abroad. However, only 11% of all recoveries included
in the database are foreign.
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