| Reason for ringing is
understanding and monitoring - - migration and movement - productivity, age and numbers of young - health and development Ring usually has address of British Museum and a unique combination of letters and digits . It is of a light alloy - eg manganese and aluminium |
|
| Reason
for ringing is understanding and monitoring - - migration and movement - productivity, age and numbers of young - health and development Ring usually has address of British Museum and a unique combination of letters and digits . It is of a light alloy - eg manganese and aluminium |
|
| Birds are weighed and this is
recorded with the time, as a 20% change can occur over a day. A 12 gm bird can lose a gram over night and 2 or 3 grams when migrating. Annual moult to repair wear and tear on plumage is "expensive", but some birds moult twice a year. First set of feathers are grown quickly to get fledged, and these are of lower quality. Later, in the Autumn a partial set may be grown to replace the worn feathers of the wings. A 15 month old bird will grow new flight feathers, body feathers might last several years - the whole life of a Tit. |
|
| The first catch to be examined
was a male Great Tit - a broader belly band showed this. Wing length was 77mm and weight 16.7 gm. The second bird was a female with similar wing length but greater weight. The picture shows her as bird 198. |
|
| Fat strategy was discussed.
Reed warblers put on enough fat for a whole journey, but swallows just enough to carry them to the next stop. This means that when habitats are lost and staging posts are not there for refuelling a migrating bird may die prematurely. Lighter birds die earlier. |
|
| BTO
catch and ring 850,000 birds a year - 2000 trained licensed ringers are at
work. 50% of small birds die in a winter, their clutch is of up to 15 eggs to compensate for losses. The miracle of migration brought to our attention by ringing replaces myths such as the hibernation of swallows in farm pond mud! |
|
| Black Tailed Godwits mate for
life but migrate to different wintering countries: they return within a few
days of each other and to the same nesting place. They return via New Zealand and East Asia, where estuarine habitats have been decreased by draining saltmarshes - so cannot always complete their journey. |
|
| Questions included - do coloured
rings increase predation? Answer - apparently not, evasion is not affected and this is the main defence. Which ringers use blue plastic nose-clips on ducks beaks? Answer - the Portuguese: they can be seen while swimming. |
|