Cuckoo patience rewarded

Given the appalling weather conditions in April, it’s no surprise that the Reed Warbler breeding season got off to a really slow start in 2012. A team of BTO staff monitor two populations near Thetford, one on the Nunnery Reserve and one at a site near Mundford, collecting data for the Nest Record Scheme and the Constant Effort Sites ringing scheme.

The first egg recorded in 2011 was laid on the 1st May, with many birds incubating by mid-May. The strong headwinds experienced during migration and the reduction in reed growth under low spring temperatures have conspired to delay the 2012 season, however; while the first female started to lay on 7th May, many birds have yet to complete their clutches.

All this must have been very frustrating for the Cuckoos, which have been back and bubbling away at both sites since the middle of April (click here for the latest developments in the BTO Cuckoo project). Their desperation to lay may explain the relatively high parasitism rates of the early clutches, with Cuckoo eggs appearing in four of the nests at Mundford thus far, the first of which hatched on 23rd May.

Before and after – the first Cuckoo egg of the year and the chick shortly after hatching on 23rd May, taking a breather between removing the first and second Reed Warbler eggs from the nest.

The first Cuckoo egg in a Reed Warbler nest at The Nunnery was recorded on the 28th May, a welcome return after a complete absence of parasitism in 2011 (although the warblers may beg to differ) save for a single egg in a Dunnock nest. Cuckoos continue to be very active at both sites so it will be interesting to see whether we can top the total of 12 parasitised nests monitored in 2011.

Thanks to Dave Leech for the pictures and writing the blog post.

Not a 'fair way' to go

We occasionally hear of some very unusual and unfortunate deaths of ringed birds, and the demise of Mute Swan W03598 is no exception. Originally ringed as an adult in September 2000 at St Dogmaels, Cardigan (Dyfed), it was seen in Llanelli (Carmarthenshire) in December 2011 (60 km from St Dogmaels). It presumably spent the winter in the area as it was rather bizarrely struck and killed by a golf ball whilst flying low over Machynys Golf Club, Llanelli yesterday.

It's rare for us to hear of golf-related deaths: a quick check of the database shows at least 12 recoveries attributed to golf balls, including such species as Canada Goose (Surrey), Mallard (Somerset), Kestrel (Dorset), Black-headed Gull (no fewer than seven birds), Swift (Merseyside) and Sand Martin (Tayside)! Even more unlucky was the Barn Owl that died after becoming tangled in golf netting in Devon.

King of the Sea

With the Constant Effort Site (CES) ringing in full swing, we were out yesterday at our local reed bed, Cranwich, Norfolk. The weather was excellent and the Reed and Sedge Warblers were singing at full volume. It was a great session with 54 birds caught, not bad for a 3 hour session before work.

One of the highlights was an adult male Kingfisher (below), caught in the top shelf as it flew between two pools. This bird was quickly processed and released.

We've had a few recoveries of BTO birds travelling between ringing sites and getting caught by other ringers in the UK and Ireland but very few go across the sea. This morning we heard of a Kingfisher that was caught by another ringer in the Netherlands! There have been nine reports of BTO Kingfishers going abroad and this is the second for The Netherlands and the fifth to be caught by another ringer abroad.


View Kingfisher to the Netherlands in a larger map

This bird was ringed by the Merseyside Ringing Group as a juvenile on 24/06/2011 at Woolston Eyes, Warrington, Cheshire (red pin) and caught at Kampen, Overijssel, Netherlands (blue pin) on 12/05/2012 (575km in 323 days).

Thanks to Rachael Barber for the photo.

The Peregrine Project in Aylesbury

Following the theme in our previous post we'd like to share some good news from Buckinghamshire. 


Dave Short writes:
In mid-2007 we noticed that a young pair of Peregrine had taken up residence in the middle of town, 200ft up on a Bucks County Council office building. Bill Robson and myself, who at the time were volunteering for Aylesbury Vale District Council Barn Owl Project, approached Bucks council about placing a nesting platform on the building. The two councils worked together and a platform was duly erected in spring 2008, although sadly no birds bred that year.


In both 2009 & 2010 two birds were seen together, but no evidence of breeding was seen and the platform remained vacant. Then, in 2011 things began to look more promising. In late spring, two Peregrines were seen copulating and an egg was laid on the platform, though sadly it didn't hatch. 


With high hopes for 2012, we decided to put two web cameras on and around the platform in order to get closer to the action, and an anonymous donor kindly paid for their purchase and installation. Sure enough, the Peregrines bred this spring, and we now have two chicks age 3 days and 2 days--the first confirmed Peregrine breeding record for Buckinghamshire! If all goes well, we will be colour ringing the chicks in due course.




To keep up to date with what's going on in the the first ever Aylesbury Peregrine nest all you need to do is follow the Aylesbury Vale Channel on You Tube here.
Here is their latest video from 2 days ago. Enjoy.


To read more stories about Peregrines in the Demog Blog go here!

Muddy Peregrine finds a mate

We recently heard of a fascinating colour ring story... On 22nd April, a pair of Peregrines were seen hunting offshore at Selsey Bill, Sussex, catching a pigeon and bringing it to the beach. They then spent an hour taking turns eating it in front of the gathered sea-watchers, where it was noted that the female of the pair was ringed (pale blue CG). Video of the birds was also posted on BirdForum TV.



The origin of this bird was a rather more interesting story, though. It wasn't ringed as a chick in the nest, but soon after fledging in 2010 had been found stuck in the mud of the River Severn! It was taken into care at the RSPCA centre at Westhatch, given a good bath and then needed to be 'hacked' back into the wild. Thanks to the Hawk Conservancy, it was kept in a release pen near Ringwood, Hampshire, along with three others birds from around the southwest and all were successfully released.

Thanks to Ed Drewitt and Graham Roberts for the details of this happy ending, and to the Hawk Conservancy for the photo of the four hacked birds.

Reed Warbler in the Net

The humble Reed Warbler doesn't often feature in blog posts about passage or migration as it is too ubiquitous. The home range of the scirpaceus subspecies spans across Eurasia and Africa and they can be found in a variety of habitats, typically near water. Breeding in the northern hemisphere as far as 60 N in Scandinavia and wintering as far south as the Congo basin or sometimes even further.

During recent weeks the arrival of reed warblers across the country has been documented "in the net" - both by ringers using mist nets and birders via the web.

The table below shows where Reed Warblers have been submitted by 'BirdTrack-ers', with the earliest records coming from eastern and south counties of England.

Numerous reports of Reed Warblers can be found in the blogosphere, as you can see from the selection below.

The earliest report I found was a reed warbler singing on the 12th april in Cotswold Water Park. Peter Alfrey reported one in Beddington on the 15th of April in his blog, and the same day one was reported in Pierrepoint Holme by the South Notts Ringing Group. A few days later, on the 19th, an early bird was reported in Walney BO. In South Bucks Chirs and Denise Lamsdell reported their first reed warbler of the summer on the 21st April, the same day that Julia wrote about ringing one in the Bristol area. By the end of April many had arrived in the UK, including one reported 'in the nets' at Trimley Reserve on 26 April by volunteer Anna Alum in 'Mick’s Blog'. The Avon Birds blog tells us that a reed warbler with a Portuguese ring was controlled in a ringing session on the 28th. And finally, Rachel Barber recently told us about reed warbler ringing in Cranwich in Norfolk.

However it was not the excitement caused by witnessing the wave of reports of Reed warblers in Britain that prompted me to write this post. What really helped to illustrate the feat of migration was news of a bird with a GBT ring trapped at Merzouga (Morocco) as it completed its crossing of the Sahara Desert. Standardised ringing is carried out there every spring by a Catalan ringing group.

Yasmina, Merzouga, Morocco; photo from the Yasmina blog.

A visit to the Yasmina blog is worth the click as the pictures are great and the array of species is amazing, including some UK-ringed birds.

From the totals summary below we can see that so far in 2012, they have caught 122 reed warblers - not bad for a little oasis in the desert!

Ringing totals from Yasmina, (Acrocephalus scirpaceus = Reed Warbler). Source: Yasmina blog

So, Reed warbler passage is ongoing - some birds will be still on the move while others will already have begun breeding. No doubt you will be hearing about breeding Reed warblers very soon, as BTO staff based in the Demography Unit are undertaking a great little project examining the breeding biology of the species at a site in Norfolk. Watch this space...