The foundation on which bird conservation is based is the in depth knowledge of bird species, their biology, ecology and how their populations change over time. We can learn a great deal about birds by observing and counting them, but in order to investigate things like how long they live and where and when they move, we need to identify birds as individuals. Ringing birds with light-weight uniquely numbered rings makes this possible. This allows us to investigate the life history traits of individual birds and to track them over time. This valuable research tool allows us to collect information on dispersal, migration, longevity, behaviour, survival rate, reproductive success and population trends. By ringing birds, we can ascertain the productivity of a population of birds (i.e. how many young birds leave the nest and survive to become adults) and the survival rates of adults in the population from one year to the next. We can assess how stresses such as breeding, migration, severe weather and human disturbance affect populations. Armed with this information, we can understand the causes of population declines and implement the appropriate conservation actions.
In general, bird ringing involves placing a metal ring on a bird’s leg. While these rings are uniquely numbered, the inscription is very difficult, if not impossible, to read in the field, and so the bird must be recaptured in order to learn anything from it. However, the use of colour-rings negates the need to recapture birds, as these conspicuous rings can be read in the field using a telescope or a camera. This means that researchers and birdwatchers can identify individual birds numerous times with minimum disturbance to their behaviour.
|Colour-ringed Brent Goose Branta bernicla. Paddy Dwan|