As the seasons change our thoughts inevitably turn to the colder months ahead. So what better time to look back to those bright early days of spring, when East Dartmoor’s woods were bursting into life. By pairing the stats from this year’s bird breeding season, with some stunning photos of the birds in action, this blog is an opportunity to celebrate the pied flycatcher, a migrant species that’s been monitored here since the 1950’s. Arriving in April to breed, pied flycatchers have long since left our shores departing in early to mid June, but they have certainly not been forgotten. The results from this season’s nest box monitoring provides valuable data that is being used by RSPB scientist, Malcolm Burgess, to inform conservation work for this species. Although the overall picture for pied flycatchers is one of decreasing numbers, the results from this season at East Dartmoor are positive…
From the first week of April until mid June, RSPB scientists and a team of Natural England volunteers spend hours in the woods recording vital data from all different aspects of the bird breeding season: from studying the abundance of food; to checking nest boxes throughout Yarner Wood and the Bovey Valley Woods. During the season, Reserve Warden, Bryan Thorne, and the Natural England volunteers make weekly checks of over 500 nest boxes – a huge but rewarding task. Malcolm Burgess, RSPB, has been ‘number crunching’ the data they collected this season and these are the 2018 results:
Highest ever number of pairs of pied flies nesting on the reserve, 87 pairs (previous high was 86 pairs in 1990).
Numbers of pied flycatcher pairs increased for the fifth consecutive year.
Note: This is partly because of a recent increase in the number of nest boxes 28% of boxes were used by pied flycatchers in 2018, the highest rate since 2010 but not near the 45% occupancy rate of 1990.
Clutch size was a little below the long term average, the number of young fledged per nest was around average at
4.6 young per nest.
But there is more than one way of recording the activity of the pied flycatchers and when Reserves Warden, Bryan Thorne, is not out surveying the nest boxes around the reserve, he can be found behind the lens of his SLR camera. He uses a clever device called a remote trigger – this enables him to stand further away from the birds and not disturb them. As a result he has been able to record the antics of the pied flycatchers using the nest boxes, in beautiful detail. His stunning photographs, showcased here, really capture the fast moving action of the bird breeding season.
Pied flycatchers fly over 5,000 miles from West Africa to breed in East Dartmoor’s woods. In early spring, the fresh new leaves of the oaks are very palatable for caterpillars and as the migrant birds arrive there is an abundance of food for them in East Dartmoor’s woods. As a separate study from the nest box monitoring, scientists are also monitoring the availability and quantity of food available for the migrant birds during the breeding season, they do this by studying the two main food sources, caterpillars and flying insects.
Other spring migrant species, such as the redstart and more familiar species, such as blue tits will also use the nest boxes. The data from these more numerous species is equally as important as the pied flycatcher records, as it helps build a whole picture of the breeding season. The following data was recorded for 2018:
Occupation of boxes by blue tits has declined a little in recent years, and in 2018 clutch size and the number fledged was also low
29 pairs of great tit nested in the boxes
We also had small numbers of marsh tit, coal tit and redstart breeding in the nestboxes
The headline stats from this year’s nest box monitoring scheme look positive and we would like to thank the Natural England volunteers for the never-ending enthusiasm and experience that they bring to the Nest Box Monitoring Scheme, year after year. Many of these spring migrant birds are in steep decline. But data collected this year will inform vital conservation efforts as scientists continue to look for answers. With thanks to Malcolm Burgess for providing this year’s data from the nest box monitoring at East Dartmoor and to Bryan Thorne for sharing his stunning photographs.
Written by Kate Smith, Woodland Trust
To find out more about the conservation work for pied flycatchers visit http://www.piedfly.net/
You can also read more about Malcolm Burgess’s research at East Dartmoor in these two blogs (Part 1)Woodland birds’ response to climate change
(Part 2) Woodland birds’ response to climate change
Camera used for the photographs: Canon 7d Mark 2, Canon 100-400mm lens
There are numerous remote trigger devices – a list can be found on Amazon here – Remote triggers for Canon