During spring and summer 2015 I had the great pleasure of working on a research project organised by the Stiperstones and Corndon Hill Landscape Partnership Scheme to try to establish why the local Curlew population, in common with those in many other areas, is in steady decline.
The aim of the project was to locate a minimum of 12 Curlew nests, install remote cameras to try to discover the causes of nest failure, monitor hatching success and hopefully radio-tag any resulting chicks to assess chick survival to fledging.
Curlew nest with 4 eggs in a silage field
Adult Curlew on a nest on common land
Click here to see a Curlew returning to its nest.
A couple of nights ago we held the second of two farmer and land-manager feedback evenings in one of the local village halls so I can now share the results with you too.
In total 13 nests were located but one of these was never seen to contain eggs. Of the 12 nest that had eggs only 3 managed to produce chicks, 1 x 4, 1 x 3 and 1 x 2.
Hatching Curlew egg - one of the few to survive long enough to do so
The causes of failure of the nine nests that failed at the egg stage are shown in the pie-chart below. The main predator was, unsurprisingly perhaps, the fox.
Caught in the act - a fox takes a selfie just before tucking into the 3 Curlew eggs
The cause of desertion at the one nest was not established but it was NOT the camera as the birds had been reacting normally for a number of days after it was installed.
The nine hatched chicks were all fitted with miniature radio-tags whilst still in the nest. Two complete broods (totalling 7 chicks) failed to last longer than 4 days before they were all predated!
Radio-tagged Curlew chick, about a week after tagging.
Nearly 75% had already been predated by this stage.
The remaining two chicks lasted about 10 days and 28 days respectively before they too were both predated by mammalian predators. Not a single Curlew chick survived to fledging!
Tagged Curlew chick at nearly 1 month old. Unfortunately this last surviving youngster was predated by a fox a few days later
Several other pairs, where no nest could be located, were also kept under observation and these too appeared to have failed completely. Despite a plea for records from volunteers in the three local Community Wildlife Groups there was not a single instance or report of any of the local Curlews alarm calling late on in the season.
Curlews are long-lived birds with the BTO longevity record standing at over 31 years and 10 months. Evenso they clearly need to get some young off to sustain the population. The project is aiming to run for another two breeding seasons, increasing the sample size of nests monitored and thereby more accurately determining the causes of nest failure on a local level. There are plans, working alongside the Game and Wildlife Conservation Trust, to instigate increased levels of predator control locally and maybe trial electric fencing around some nests but all this will depend on the project sourcing sufficient funding. If something is not done soon I fear that the iconic bubbling of the Curlew may be lost from the hills and valleys of South Shropshire in our lifetime and that would be an absolute tragedy.
Whilst carrying out this work I managed to locate and identify two nesting birds out of the 20 Curlews we had colour-ringed at the communal roost on the Montgomeryshire Wildlife Trust's Dolydd Hafren reserve on the Severn between Welshpool and Newtown. Another of these birds has since been recorded wintering at Devoran in Cornwall. I am hoping to colour-ring more adults there this winter, if the river levels allow.