Friday morning saw a somewhat bleary-eyed and hilarious group of A Rocha Kenya staff and volunteers return from another all-nighter on Mida Creek catching and ringing waders – or doing our best to, at least! We’ve been focussing on trying to ring waders (shorebirds) at Mida over the past few months in particular the past 4-6 weeks to try and get data on the weights of birds and their moult patterns in the build up to them departing on migration back to their breeding grounds in Asia and eastern Europe.
This is one of the most interesting times of the bird calendar in terms of these birds. They have just spent possibly even nine months in Kenya after the last breeding season hanging out on Mida where life is pretty easy for a wader – warm conditions so no cold to fight, not many predators to worry about just a bit of disturbance from fishermen and tourists. As a result they don’t need to feed too heavily nor carry much fat to survive any potential harsh conditions – unlike their cousins who are wintering in Europe where a cold spell can come in and freeze their food source and can lead to death if you’re not fat enough to live it out till a thaw comes in.
However at this time of the year, March-May, birds are frantically foraging to fatten for the 6,7 or even 10,000km journey that they’ll be making back to their breeding grounds in Asia. This means as we catch them for ringing and weigh them, over this period you can see the weights of the birds increasing steadily and then numbers of adults suddenly start to reduce as adults leave for the north while mostly the youngsters from last year’s season stay behind and probably won’t migrate but will chill til next year when they’ll head home to join the fray of trying and find a territory and a mate to raise a family.
Moult-wise, it is also interesting. Adults have all completed their non-breeding season wing moult and have fresh, new, strong feathers to take them back to Asia and bring them back to Mida in August. Young birds, depending on the species and the population, will either have simply retained the feathers they grew in the nest last year, or will be moulting some in preparation for the next year spent in the harsh sunlight of the tropics which bleaches feathers like crazy and wears them out fast.
The other neat thing to see is to go to Mida in the evening in early May and watch for flocks of birds that are setting off for Asia. We did that not long ago – headed out about 6pm with the tide low and birds spread all over foraging away. There was already a clear reduction in the numbers of birds around but still there were adults in 70-90% breeding plumage who would be heading north at any point. At about 6:15pm a flock of c.40 very handsome Curlew Sandpipers in their brick-red breeding plumage landed about 60m from us calling excitedly and looking alert. They only were there a few minutes before they took off trilling loudly and started climbing higher calling as they went. They climbed steadily heading off across the water and then started circling whilst still climbing making 2 or 3 circuits still calling quite clearly. After the last circuit they then adjusted their bearings and headed off just east of north still climbing as they went and flew on and on until they were out of sight.
Amazing to think that within a matter of hours they would be over Somalia and only a couple of days easily beyond the Middle East. Below is a photo of a Curlew Sandpiper on its nest in its lovely plumage. Then a few images of one of our recent wader nights..
by Benjo Cowburn
by Benjo Cowburn