The latest update from Dunsford Woods from David Price...
Having provided an update for previous visits, I'm now in the situation of "I've started so I'll finish", so with apologies for the fact that this is becoming something of a rather rambling blog I'll carry on inflicting my home-spun observations on you.
Well, in Box 20, (where the "first Dunsford egg" was laid), three young had hatched yesterday with 4 eggs, still to do so. In their monograph on the Pied Flycatcher, Lundberg and Alatalo give a range of 13-16 days for incubation so this was just about on cue after 13 days. On the subject of incubation, I have noticed that in several cases on my previous visit (on 12th May) I recorded typically 6 or 7 eggs that were warm (or perhaps "warmish") so on the basis that incubation had started and I assumed the clutch was complete, only to find yesterday that the clutch size had increased by one or two eggs or in one case from 6 to 9. I started to doubt my ability to asses warm and cold. However looking at the chapter in the book on incubation more closely, they mention that the female "actually starts incubation by gradually spending more time on eggs during the laying period" and by the time they get to laying the 5th egg 82% of females will spend the night on the nest, though "full incubation normally begins when the last egg is laid". It would seem that these "warmish" eggs that caused me confusion are a result of this increasing occupancy of the nest towards the end of laying. There are several other pairs that are not far behind, and so should be hatching over the next few days - and as I sit here with the fire lit, and the wind and rain beating against the window, (and a rather unsettled weather forecast for the next few days) it's slightly worrying that this is perhaps not going to be great for feeding small young and trying to keep them warm. ...continue reading "Update from Dunsford Woods 18th May"
David Price has been monitoring nestboxes at Dunsford Woods in the Teign Valley since the 1980s. As he sends us such good updates we now include them here as a blog. Here is his update from 5th May.
The Pied Flys are now either laying or finishing off nests, I reckoned that there may be around 22 pairs - perhaps just a couple more than last year, though some nests not yet laid may in the end not be used, and others may still be built. Box 20, the celebrated "first egg box" had gone from one to 6 eggs (still cold), and 4 others had 1 or 2 eggs. I also re-captured a female - a bird ringed as a breeding adult in 2013 at Dunsford, and recaptured last year as well.
Though the tits seem quite numerous throughout the woods generally, they haven't been queuing up to use the nestboxes this year. There were perhaps 24 occupied in total, compared with 30 last year. Some are incubating, others still laying, though I did have several which seemed to have finished laying some days ago, but eggs were still cold - (perhaps they are having a "breather" before getting down to the serious business of sitting on eggs for hours on end). I hope they haven't abandoned. ...continue reading "Update from Dunsford Woods 5th May"
Funders: Woodland Trust, Natural England
Summary: We know spring temperature plays an important role in determining the timing of breeding of insectivorous woodland birds; invertebrate emergence and availability is strongly linked to spring temperature. This project is creating a fine scale temperature map of East Dartmoor NNR so we can examine this in more detail. We might expect warmer territories to be occupied first, and to initiate breeding earlier. The temperature data will also contribute to a Heritage Lottery Project on Barbastelle bats; the temperature data will be combined with radio tracking movement data to look at how temperature influences foraging behaviour.
Partners: University of Exeter, University of Edinburgh, British Trust for Ornithology, Ken Smith
Summary: Some animals can adapt to climatic change by altering timing of spring migration or emergence and the onset of breeding. In some species this has been shown to cause a mismatch between predators and prey, when phenological changes differ between species. Such a mismatch is thought to contribute to the 40% decline in UK Pied Flycatcher populations observed since 1990. Using national scale data we are investigating spatial variation in caterpillar availability (prey) and bird (predator) breeding parameters in relation to climate and its population consequences.
Partners: University of Exeter, British Trust for Ornithology, University of Groningen
Funders: Natural England, Devon Birds, British Ornithological Union
Summary: Using new technology (geolocators) we are determining migration timing, routes, strategies, stopover locations and sub-Saharan wintering locations of UK breeding pied flycatchers. We hope to gain insights into how, where and when pied flycatchers migrate through Europe and Africa as a fundamental gap in our knowledge is quantifying timing of spring migration and arrival date to breeding grounds by individual birds, the influence of climate on this, and potential carry-over effects from wintering locations and migratory stop-over sites.