Naomi Davis, volunteer at RSPB Ynys-hir summarises how the nest box survey and other nests has gone this year...
Small nestbox monitoring comes to an end for another year. The late cold-snap pushed back the breeding dates of the blue and great tits to coincide with the pied flycatchers, normally the tits nest 2 weeks earlier, but didn’t appear to affect our later continental migrants too badly. Our woodlands of ancient oak provide perfect natural nest sites for pied flycatchers, but they will readily take to boxes in patches of younger trees or conifer. Due to the inaccessible nature of the natural nests the best way we can monitor breeding in our birds is to use nestboxes.
We had 35 nesting attempts by pied flycatchers in boxes, and just over half the broods successfully fledged. Sadly the pieds, as well as blue and great tits, came under attack by nest predators; barely a single nest survived in one particular wood. So whodunnit? What we know is the predator in question was meticulous enough to find multiple boxes and has a territory large enough to cover the woodlands of the blue trail. My best guess is a weasel. These are known opportunists, smart enough to recognise a nestbox and to remember sources of good prey year on year. The same area of woodland suffered a few losses last year from a weasel, I know because I found it in a box munching on some pied flycatcher eggs!
In happier news, I was quite surprised to find 3 boxes occupied with wren nests this year, something I’ve not come across before. The entire box is stuffed with moss and a small chamber created inside for the young. This brood is quite close to fledging and I’m glad I got to see them before they moved out.
Nestboxes are fantastic in that they allow us a unique insight into the world of birds, but only a small portion of our birds will use boxes, so what about everything else? The oystercatchers returned to their preferred nesting spot atop the wall by Domen Las hide; 3 eggs produced 3 young which all survived through to fledging! As I write another pair has setup shop on the wall again and is currently brooding 3 eggs.
We’ll have to see what nesting late in the season will mean for that plucky pair. A pair of blue tits nested in our nest-cam box just outside the visitor centre, and many enjoyed watching the attentive pair caring for their five chicks which all fledged successfully.
This year I was lucky enough to find a few different “wild” nests around site, most notably (and audibly) 3 great-spotted woodpecker holes containing some very noisy young. One tree in particular became a temporary visitor attraction being right next to the path on the green trail – just shows how close you can get to the wildlife here!
My first find was a song thrush, their nests are very similar to those of the blackbird but the song thrush lines their nest with muddy clay to create a firm base onto which she lays her beautiful blue eggs. 4 chicks fledged from this nest, what a difference 2 weeks can make!
The best nest treat this year however was won by the humble pair of blue tits who chose to nest inside a broken bow of an oak right next to Ynys-hir hide! Watching the frantic antics of the parents from less than 4 feet away definitely proved a hit with visitors.
We are just at the beginning of the best time to see our key woodland species, knowing a little bit about the habitats these birds use and their behaviour can be the key to getting to see them. Below I will go through some of the best places to spot one of our key species and how to give yourself the best chance of memorable encounter. Pied Flycatcher’s are the species a lot of people come to Ynys-hir wanting to see, here’s a bit of advice on seeing these beautiful small birds.
Pied Flycatcher’s are a small bird, slightly smaller than a sparrow, the males are black and white with two white dots above their beak and the females are brown and white. They are busy birds, often moving quickly between perches, however they will sometimes perch for longer and can provide great views and photo opportunities.
Pied Flycatcher’s are a species associated with open canopy, predominantly Oak woodland, they prefer an open understory (woodland ground level vegetation) with lots of access to the ground. Early in the season, before the caterpillars are abundant on the Oak leaves they feed a lot by picking small invertebrates from the ground. Access to the ground is also vital when there is heavy rain in the spring, this rain can knock caterpillars (their main food source) from the leaves which requires the Pied Flycatcher’s to go foraging for them at ground level. Despite their name they don’t actually catch that many flies on the wing when in Britain, they will do it on and off later in the season but this flycatching behaviour has been seen much more on their migration staging areas and wintering grounds in sub-saharan Africa.
How to see them
Listening for these birds can give you a better opportunity of seeing them but their song is quite subtle, it took me a long time to learn and to distinguish from all the other birdsong in the woods. If you don’t know the song then there are other ways to get a look at these beautiful birds.
It is important to remember that Pied Flycatcher’s are birds of woodland edge, fringe habitats allow access to open areas for feeding, so standing in an open area at the edge of the woodland is a where you want to be. The Blue route at Ynys-hir takes you through a series of these edge habitats and is often where visitors get best views of Pied Flycatchers.
Helpfully these small birds have a real preference for nest boxes, we have lots of these boxes dotted round the woodlands, if you see a nest box then it is worth taking a moment to see if anything is hanging around it, if you’re lucky then it will be occupied by a Pied Flycatcher. Please remember not to get too close, if you observe from a distance you are far more likely to see some interesting behaviour.
Finally, and this by far the most important piece of advice I can give you – stop and be still, don’t talk or think or move around, just be still and quiet and observe. If you put yourself in the right habitat and you stay nice and quiet and wait then things will start happening around you. Just because you don’t see anything doesn’t mean they aren’t there, often your presence will have spooked the birds and given time they will begin to settle back down and get braver. All our trails are loops but that doesn’t you mean you have to walk all the way round them, there are plenty of benches and tree stumps around the reserve, no one is going to stop you sitting under a tree and watching the world go by. Watching wildlife is a mixture between a bit of knowledge, a lot of patience and blind luck, there’s nothing you can do about luck but the other two are in your hands.
The good thing is that all of the above also applies to one of our other migrants, the redstart, these birds share the same sort of habitat so keep your eyes out for a flash of red when looking for Pied Flycatchers.
Why not join our Wardens on our Dawn Chorus event on the 12th May where you will have their expert advice on hand. Click on the link below for booking information or ring 01654 700222.
Did you know, we have just over 300 nest boxes at Ynys-hir for our small birds? In the past few weeks we’ve been busy cleaning out all boxes and mending any problems before the birds start surveying for potential nest sites in the coming weeks. Raising a brood of chicks can leave a box looking (and smelling) pretty bad so we give the birds a helping hand by removing any old nest material from the previous year, this helps keep the vast amount of fleas and parasites away from any young vulnerable chicks.
The target species we’re hoping to attract is pied flycatcher (Ficedula hypoleuca), but we also get a fair amount of blue tit (Cyanistes caeruleus) and great tit (Parus major) too. The pied flycatcher is a long-distance migrant, travelling all the way from sub-Saharan Africa to spend the spring and summer with us. Sadly their numbers are declining fast but mid-west Wales is a hotspot for these birds and Ynys-hir is no exception. Pied flycatchers breed here every year and studies have shown that these birds are very faithful to their breeding sites, often returning year after year to raise a brood in the same woodland or even the same nestbox- that’s pretty impressive!
Our interns and conservation volunteers have been working hard in the woodland over the winter to remove sections of bramble (in some places by hand!) to reduce vegetation grow-back in the spring and summer. Having clear areas of understorey to forage is vital for pied flycatcher as they increase their intake of caterpillars and other leaf-munching bugs to feed their chicks. More boxes have been installed in these areas of management so we can monitor the effects (if any) on the pied flycatcher breeding population.
This year we’re also adding 10 new boxes along the red trail for redstarts (Phoenicurus phoenicurus). These birds are spring migrants too and like to nest in rot holes and open cavities but will happily take to artificial boxes provided the hole is big enough (at least 42mm). Their nests look very similar to pied flycatcher, a cup woven from grass and leaves but then furnished with a layer of soft feathers whereas flycatchers leave theirs bare.
National Nest Box Week takes place every year in the second full week of February, this year it’s the 14th-21st February. Why not get into the spirit at RSPB Ynys-hir by making a nest box on Wednesday 21st February 1-3pm Nestbox’s £5 per kit.