Pied flycatchers at Yarner Wood

Pied flycatchers are quintessential Dartmoor birds. They tend to live in upland Sessile oakwoods on the fringes of Dartmoor. They are migrant birds – spending the winter in Africa only to return to Britain in the spring to breed here. As their name suggests these birds feed on flies / insects – they sit on branches and then flit out to catch their prey. For me, they are very smart looking birds and I always try and see them once April arrives. The following set of photographs were taken in Natural England’s Yarner Woods north of Bovey Tracey on Thursday this week.

Pied fly 5
This is the male. For those who don’t know – ‘pied’ means black and white

Pied fly 6
 The two white blobs above the bill are a characteristic feature of the species. Note also the blue ring on the leg – this bird has been ringed in 2015 (or before) – either at Yarner or elsewhere and has returned after its migration to Africa

Pied fly 3
This bird at Yarner was very confiding – often they spend much of their time high up in the canopy and are hard to see

Pied fly 2
Pied  flycatchers are pretty vocal – their song / call is quite characteristic – listen to it here with David Attenborough

Pied fly 1
Traditionally pied flycatchers would have nested in holes in trees but they also nest in boxes. Here the male  is already feeding the female in the box. The widespread use of pied flycatcher nest boxes has undoubtedly helped the species. There are now less old trees with holes than there were formerly.

Yarner Wood 3
This is the classic habitat at Yarner Woods – sessile oak woodland with birch – just a few hundred metres up from the car park / Natural England Office.

Pied fly Devon Atlas
This is the distribution map of pied flycatchers in Devon from the fabulous Devon Bird Atlas 2007-2013 (a must have book- see here). Its strongholds on Dartmoor are in the Bovey, Teign and Dart Valleys. Fortunately its population appears stable.

A huge amount of research has been carried out on Devon’s pied flycatchers by Malcolm Burgess who runs a website PiedFly.net see  here. He, along with other researchers have recently published a paper which details the migration routes of pied flycatchers which have been ‘installed’ with geotrackers – see here.

 

Bog bush crickets – doing well?

The bog bush cricket is a pretty rare animal nationally and one of its strongholds is south east Dartmoor and its hinterland. There are two colour forms – a brown animal with a green line on the underside of the abdomen and a brown form with green lines on top and underneath. They are pretty smart looking animals!

Bog bush cricket maleHere is a male with green on the top of the body – you can clearly see the reduced wings which are used to stridulate i.e. make the characteristic buzzing noise – when I photographed this individual at Chudleigh Knighton Heath (the Devon Wildlife Trust reserve) I could clearly see the wing cases moving.

This is the song of this actual individual singing recorded through a bat detector

Bog bush cricketHere is the brown version – another male – again at Chudleigh Knighton Heath

Bog Bush-cricketHere is the female – again a green form – note the long sickle shaped ovipositor – I photographed this individual in 2008 at Yarner Woods

BBcricketHere is the distribution map of the bog bush cricket courtesy of the National Biodiversity Network

 Bog bush crickets are secretive animals and can be difficult to find. However using the bat detector their inaudible high frequency calls become audible and are a real help in locating individual males. One thing that has been obvious on my last few bog bush cricket trips has been the prevalence of another species – the long-winged cone-head in the same habitat. This is interesting as prior to 1990 long-winged cone-heads were absent from Devon (see here for the distribution maps) – on Chudleigh Knighton heath I would estimate that the cone-heads outnumber the bog bush crickets 3 to 1.

LWCH - femaleHere is a female long-winged cone-head (long sickle shaped ovipositor) photographed at Chudleigh Knighton – it was 12 ” away from the green male bog bush cricket above. This photograph demonstrates why they are called cone-heads
– their heads are shaped like a classic seaside ice cream cone!

Bog bush crickets appear to be flourishing and are common at their classic sites but I do wonder whether the cone-heads are having / might have an impact in the future- I guess time will tell and monitoring of their progress will be required.