Remote dangers

Checking Bega's satellite tracker before fitting, Summer 2016

Checking Bega’s satellite tracker before fitting, Summer 2016

Flying into remote and dangerous areas is the norm for ospreys, particularly for those young birds making the migration for the first time. Every beat of their wings could bring them in range of water or banish them into sand; every dive could plunge them into crystal seas or into polluted sludge; every fish could be healthy or sick; every human encounter could be benevolent or inimical. Every day could be the first of many or the last. Satellite tracking can tell us a lot about the routes ospreys take, the heights they reach and the speed they go, but it can’t tell us the things that really matter to the bird. It doesn’t tell us the near misses with disaster, it doesn’t say if the water holds fish or not or whether there is a catch or empty claws. It doesn’t monitor exhaustion, dehydration, starvation, disease or injury.

From over 60 years of studying ospreys we know that only about 20- 30% reach adulthood to reproduce themselves, and this is the same for most species. For ospreys the majority of these fatalities occur in the first migration. Our own birds have proved this time and again, starting out so hopefully into the unknown. So for Bega, the travel inland into Guinea Bissau, an area where we know other ospreys have perished, is very worrying. Why has she chosen to leave the Senegal and Gambia estuaries? There seems to be water, but of what quality? Are other ospreys thriving there, or are there none?

 

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