After the high failure rate of our first broods, a successful round two of nests, we were hopeful but unsure what any third breeding attempts would bring for our Stonechats. In previous years, we’ve had only a couple of pairs try for a third brood. This time, with so many failures on the first broods, we were more hopeful that more pairs would attempt another nest.
Once again the weather was kind to us for our third nesting attempts and with the timings of the pairs again spread out, any bad weather didn’t have a significant impact. So round three proved to be a mixture of pairs who attempted three nests and succeeded, while some pairs managed technically their second broods. In total, 9 pairs went for a third nesting attempt and we managed to ring 36 chicks. Once again, we missed one nest which fledged a minimum of 4 young, so we had a minimum of 40 young fledged from those 9 pairs.
So the big news for the project is that we crossed the century mark for the first time which was an amazing achievement, both for the birds and the volunteers. Ringing the 100th chick felt like quite a landmark and a cause for celebration. We didn’t quite wet the baby’s head but it was a close run thing…
In total over the whole season, we had found 33 nests, missed 2 more nests and ringed 113 chicks, with a further 8 chicks to add to the total from nests we missed. Considering that it was as recently as 2013 that we only had 2 pairs of Stonechats on Dersingham Bog, producing 10 chicks over a whole season, the increase in the population has been nothing short of remarkable.
In trying to sum up the various territories, this is where it gets complicated… Overall, 8 of our Stonechat pairs made three nesting attempts, with 6 of those pairs being successful. One of those pairs was remarkably prolific in terms of numbers, with 5 chicks from the first nest, 6 from the second and 4 from the third.
4 of our pairs nested twice, with 3 of those pairs successfully raising two broods and one pair failed on both of their nesting attempts. 3 territories held 5 pairs of Stonechats in total, 2 of those territories changing occupants partway through the season. Those 5 pairs made a single nesting attempt each and 3 out of the 5 pairs were successful.
The territories where the occupants changed was a result of territories being abandoned by their original pairs after the first breeding attempt and later being replaced by new pairs. Curiously, one of those abandoned territories had been successful with a first nesting attempt so it was puzzling why the successful pair left. Those supposedly empty territories took everyone by surprise when they were reoccupied, with one of our volunteers literally making a chance discovery of a pair carrying food, but it shows the value of checking all the territories regularly. It perhaps also reflects the increasing numbers of Stonechats in the area now that suitable territories don’t remain empty for long during a breeding season. It’s a comforting thought that Dersingham Bog may now be a Stonechat nursery for the repopulation of West Norfolk.
It’s been a fascinating season and our Stonechats continue to be an absorbing, yet at times frustrating, species to study and our volunteers have put in a huge amount of time and effort to ensure we found as many nests as possible. It remains to be seen if next season will be just as busy and even if any more territories can be squeezed onto the reserve or whether we’ve reached our carrying capacity. We’re conscious a lot could depend on whether we experience a bad weather winter, for the first time in several years, which could have a significant impact on the numbers which return to breed. Our luck can’t hold forever.
We’ll attempt to monitor what Stonechats remain on the reserve through the winter as we did last year, to continue to build up a clearer picture of winter territory occupation. We’d very much welcome any reports of our dispersing Stonechats, both adults and juveniles, through the winter around Norfolk and perhaps beyond, as well as those which continue to occupy territories on Dersingham Bog. Meanwhile our volunteers, Roger and Irene, can probably be found recovering in a home for the bewildered through the winter… (aka the pub).