BIRDWATCH at RSPB Pulborough Brooks with Peter Hughes

AT THIS time of year, the reserve is full of families. Families of blue tits, great tits, green finches, lapwings, redshanks, swallows, foxes, badgers, and stoats to name but a few.

This year we have two very special families successfully nesting on the reserve, barn owls. If you have visited the reserve in previous years, you may have been lucky enough to watch the live pictures from the barn owl nest box above the visitor centre.

This year, both pairs have chosen to nest in new boxes, which have been put up over the last few years, and currently the adults can often be seen hunting across the reserve in the evenings or early morning.

Barn owl populations are famously bound to the fortunes of their main prey, the field vole.

Large vole populations generally mean good barn owl populations, as long as their nest sites are undisturbed. Vole numbers naturally go up and down over the course of several years and very low numbers can have a big effect on barn owls, as well as other birds of prey such as kestrels.

Last year the national press were reporting a disastrous year for barn owls. Apparently many pairs were not breeding or they were attempting to breed and having very low success. Last year was certainly rather poor for barn owls at Pulborough Brooks, however, 2005 had been an exceptionally good year, and we have been confident that the birds would bounce back over the next few years.

After looking out for signs across the reserve of these spectacular birds, we were thrilled to see activity around the boxes earlier in the year. Then we had a particularly wet spring, with a full flood event occurring as late as the first week of March.

This would have caused barn owls serious problems by removing a large section of the reserve from potential hunting areas. May and June also had periods of very wet weather, which means the adults would have struggled to hunt. The BBC's Springwatch programme graphically illustrated what can happen if there is not enough food being brought in by the adults.

This is the first year we have had two pairs of barn owls successfully nesting so close together on the reserve. We know that one of the pairs, using a nest box on the edge of the reserve, has three healthy chicks. The chicks have been ringed and the eldest, who was about a month old, was confirmed as being female, however, the other two, who were only a couple of weeks old, were too small to tell.

For full feature see West Sussex Gazette July 18