Poultry in motion – COVER STORY

Using the kind of technology that could knock you down with a feather, experts are following migrating birds by attaching lightweight electronic devices and tracing the signals with solar powered satellite transmitters. Data is then beamed back via satellite, enabling them to track every twist and turn of a bird’s journey. Satellite tracking is used to discover migration routes, the time taken and the stopping points used during migration. They can also determine where the birds spend the winter, the return routes used by adults during the spring migration and where first year birds spend the second summer of their life. In the event of losing the bird they also need to know where and under what circumstances death occurred. In order to receive and transmit location data and additional sensory equipment such as temperature and activity, a pecking order of bird tracking devices is available: * Backpack tags are designed primarily for birds. Bird tags weighing more than 4g are usually fitted with harness tubes. Smaller tags may be glue mounted. * Tail mount tags are the most common and safest method. These usually pose no problem for the birds and will fall out when the tail feather is moulted. * Leg mount tags are used where other methods are inappropriate. Useful for raptors and long legged waders, they are the last resort if the tail feathers are not fully developed and a harness is regarded as too risky.