Wednesday 23rd March 2022

Female Cirl Bunting – 23rd March 2022

A scheduled meeting with Nick Townsend, Vic Tucker and Graham Burton, one of Devon Birds’ two new Conservation Advisors, saw me taking the opportunity to arrive at dawn and get some nets up. I had a good four hours before the others turned up to start their tour of the reserve. The intervening hours weren’t the most productive I have ever spent, with just eleven new birds out of a total of seventeen, but there was enough variety to keep me on my toes and a surprise at the end.

The wintering collybita Chiffs all seem to have departed, including the obese individual I trapped last time. These have been replaced by local breeders, already with what seem to be well established territories. Three Siberian (tristis) Chiffs found themselves in the nets by the sewage works again. These were all re-trapped birds that had been present throughout the winter and, like the bird caught last week, all were having the avian equivalent of a bad hair day, moulting body, mantle, head and tail feathers. At this time of year the moulting process, with the olive edges of the retained flight feathers becoming more obvious, can make them look less like tristis but the brown head, prominent white eyestripe and lack of yellow on the breast and around the vent makes it easy to confirm their identity.

Three moulting Siberian Chiffchaffs – 23rd March 2022

I was going to say that the fact that these birds were in the middle of their pre-breeding moult was also a pretty strong indicator that they were from the east, where the breeding season doesn’t really get going until June. Then a dead-ringer for a collybita chiff, equally tatty and in the same stage of moult as the tristis, ploughed into a net. It remains my ambition to discover where these wintering birds come from. Wherever it is, there doesn’t seem to be much ringing!

Moulting collybita? Chiffchaff – 23rd March 2022. Any guesses where it might be from?

In between photographing the Sibes, to keep the Devon Birds records people happy, and removing their moulted body feathers from my sweaty hands, I processed a 1st year male Sparrowhawk, a female Cirl Bunting and, right at the end, a nice male Coal Tit. Surprisingly, this is the first Coal Tit I have ever seen at SML let alone ringed. I tried to string it into a migrating Continental bird but there was just too much olive on the mantle for that!

Coal Tit – 23rd March 2022

Final totals: 11 Chiffchaff, 1 Cirl Bunting, 1 Coal Tit, 1 Dunnock, 1 Great Tit, 1 Sparrowhawk and 3 Wren.

March 14th 2022 – A Chiffchaff smorgasbord

Moulting Siberian Chiffchaff

A beautiful spring day, only let down by a lack of birds. Out of 20 trapped this morning just five were new and only one of these was a migrant. There was a real mixture of Chiffchaffs present, identified by their ring numbers, including returning local breeders, lingering wintering birds, and one particularly scruffy looking Siberian tristis. The weight of one of the wintering Chiffs had increased from a portly 8.7g at the end of January up to a colossal 11.2g today, the heaviest I have ever encountered. Anticipating a protest from the recording software, (correctly as it happens!) I had checked the weight on two sets of scales, both of which were calibrated last week. Blowing the bird’s breast feathers apart revealed that its belly was yellow with fat. If it doesn’t depart soon it won’t get off the ground!

The Siberian Chiffchaff, which was first trapped on 21st December 2021, had managed to avoid recapture until today and what a sorry looking specimen it was. As the snow doesn’t clear from most of their breeding range until well into May, these eastern birds have a delayed pre-breeding moult relative to western european birds and most winters one or two remain at South Milton Ley until late April before departing. Todays’ bird was moulting its head, body and tail feathers and won’t be winning any beauty contests until at least mid-April!

The same bird back in December 2021

Wednesday 12th January 2022

Tristis Chiffchaff

The first ringing session of the year, with perfect weather, wind strength and direction. The reedbed is currently both unproductive and underwater so I concentrated on the area downwind of the sewage works. This proved to be a good call and 65 birds were trapped with 44 Chiffchaff, including 3 tristis and 2 UK control collybita. Also 6 Goldcrest, 3 Bullfinch, 3 Blue Tit, 3 Great Tit, 3 Robin, 1 Dunnock, 1 Blackbird and 1 Wren.

Two of the tristis were classic birds with olive limited to the margins of their flight feathers and tail and completely lacking in yellow tones except in the underwing coverts. A few years ago, the third bird would have been relegated unceremoniously to the form colloquially known as fulvescens, showing more olive on the mantle, a hint of yellow in the supercilium, undertail coverts and around the thighs. It was assumed that these birds were intergrades from the zone of overlap between tristis and abietinus. However, all the mtDNA analyses done on these birds for me by Martin Collinson’s team at Aberdeen University have come back as 100% tristis. Whilst this method only gives the maternal ancestry, I think it unreasonable to assume that hybridisation only occurs between male abietinus and female tristis.

The current thinking seems to be that if it looks like a tristis, sounds like a tristis and has tristis DNA then that’s what it is. Fortunately, all the birds were attracted into the net using a tristis song lure and gave the soft, short ‘peep’ call on release, which, as far as I am concerned seals the deal! I have posted photos of all three birds and a collybita Chiff below for comparison purposes.

tristis 1 with more olive than usual and a hint of yellow in the eyestripe.
tristis 1 – note hint of yellow in the undertail coverts and around the thighs.
tristis 1 – yellower underwing coverts than usual
tristis 2 – a ‘classic’ example
tristis 2 – note lack of yellow tones apart from faint underwing coverts.
tristis 3 – another ‘classic’ bird
tristis 3 – no yellow here either
collybita Chiff for comparison
collybita breast and underwing coverts

Wednesday 14th December 2021

Tristis 1

After three weeks with two named storms and seemingly endless days of wind and rain, I finally escaped the house and got in 3 hrs ringing at South Milton Ley before the next band of drizzle swept in. In reality, it was windier than I had hoped for and, with leafless trees and the reeds having died back for the winter, the breeze was sweeping up the valley unimpeded, keeping most birds on the opposite side of the sewage treatment works to my net rides. Just 10 new birds were trapped, which is not a good return on the six litres of fuel it takes to get there and back from Plymouth. There were compensations though; First out of the net – 2 tristis Chiffchaffs followed by 5 collybita Chiffchaffs, 2 Goldcrests and a Blue Tit.

Tristis 2

One of the Chiffchaffs had an overgrown upper mandible. This is first time I have seen this in in over 2,500 Chiffs I have ringed there. It didn’t seem to have affected its feeding though with a healthy winter weight of 7.7g.

Finally, in May this year I heard a female sparrowhawk soliciting food from a nearby male quite close to one of my net rides. On two subsequent visits I heard what I assumed to be nestlings begging for food and saw the female carrying prey into the same, inaccessible clump of trees. When I mentioned this to the reserve manager, he was, to say the least, dismissive, telling me “Sparrowhawk has never bred inside the reserve.” Not one to take kindly to having my field skills questioned, I had been waiting for the leaves to drop before investigating further and the lack of birds today gave me the perfect opportunity.

Nest located and photographic evidence secured!

Sparrowhawk nest

It was a few metres from where I had expected to find it and the tree was surrounded by impenetrable bramble, which was a shame as I’d been hoping to get close enough to look for rings in regurgitated pellets or to get a ladder up to look in the nest itself. Never mind. It was a moral victory anyway!

Friday 9th April 2021 – A little bit of quality

Adult male Cirl Bunting

I’m not keen on cold mornings and was not exactly overjoyed whilst clearing ice from the mist net poles and ringing table at 06:30 today. However, despite the low temperature, conditions were almost perfect for ringing with virtually no wind at all first thing. Unfortunately, there were virtually no birds either! Just 24 were trapped in a six-hour session and fourteen of these were re-traps. There was little evidence of passage of any kind apart from a solitary Grasshopper Warbler reeling away somewhere in the reedbed and a lone swallow which moved through later in the morning.

It wasn’t all bad though. Two of the re-traps were resident male Cetti’s Warblers and another four were local Chiffchaffs returning to their breeding site for the second or third year in succession. Of the new birds, the highlights were an adult male Cirl Bunting and a late Siberian Chiffchaff, both of which were trapped in nets beside the STW. There cannot be many places in the country where a ringer can trap Cetti’s Warblers, Cirl Bunting and Siberian Chiffchaff in the same ringing session.

Siberian Chiffchaff Phylloscopus collybita tristis

The lack of birds gave me the opportunity to start spring cleaning the boards across Marsh Ride. These gradually disappear under a thatch of grass if left untended, which makes it all too easy to misjudge where their edges are. In the interests of my personal health and safety, I like to cut away the grass to expose the boards. This is a slow process, using edging shears to slice through the matted roots along both sides of the net ride, a total distance of 96 metres. Once completed, the cut material must be raked to one end of the ride for disposal. It’s surprising just how heavy wet, matted turf is! All that remains now is for me to repeat the exercise, using hand shears, and cut the remaining 48 metres between the boards along the middle of the ride. This will enable me to set the bottom of the net a little lower in future, rather than having to avoid birds in the bottom shelf potentially encountering cold damp vegetation. Final totals were: 2 Blackcap, 3 Blue Tit, 2 Cetti’s Warbler, 8 Chiffchaff, 1 Cirl Bunting, 2 Long-tailed Tit and 6 Wren.

Tuesday 1st December 2020

Sunrise at South Milton Ley

Today’s weather forecast was too good to ignore, with a light northerly breeze expected. Any wind direction between NW and NE is ideal for trapping Chiffchaffs by the sewage works at SML as the midges (and birds) concentrate on the leeward side of the plant where I have 30m of nets. Unfortunately, the prevailing SW wind usually means that the birds gather frustratingly on the other site of the works. Nothing is ever perfect though and the bright sunshine made the nets a little too obvious resulting in a lower catch than last Thursday, although another 19 Chiffs were processed, including the first Siberian Chiffchaff of the winter.

Siberian Chiffchaff

The other highlight was a 1st year male Sparrowhawk, caught in the bottom of Blaca net by just one leg. I approached it cautiously, not wishing to fall foul of its flailing talons or bill but, in the event, it was extracted quickly and without any blood spilled. I wasn’t so lucky when I processed it. A momentary lapse of concentration enabled it to latch the talons of its right foot onto the end of my right index finger. This is not the first time this has happened and I have had to be extricated from the grasp of a particularly aggressive Kestrel chick in the past. However, with no one else to assist and the bird increasing its grip every time I tried to free my hand, I had to use some initiative or let the bird go without weighing it. Fortunately, I was able to hold my pen in my mouth and use the tip to gently prise the hind claw off my finger whereupon the bird let go!

1st year male Sparrowhawk

Final totals were 36 birds with 28 new: 1 Blue Tit, 1 Cetti’s Warbler, 18 Chiffchaff, 1 Dunnock, 1 Siberian Chiffchaff, 1 Firecrest, 1 Goldcrest, 1 Reed Bunting, 3 Robin, 1 Sparrowhawk and 5 Wren

New year, new photos.

Siberian Chiffchaff Phylloscopus collybita tristis 26 January 2018

Given the continuing overcast weather, combined with other commitments over the festive period, I decided to make a start on revising some of the other pages on this blog. I’ve been working on a paper detailing the population dynamics of Chiffchaffs wintering at South Milton Ley. British Birds sent the first draft out to five reviewers and it returned with a lot of comments. Fortunately, these were almost entirely constructive and I have recently resubmitted a significantly revised second draft. When (or if) this is eventually published, I intent to expand the section on wintering Chiffchaffs in the blog considerably. However, in the meantime I have updated and sorted all the photos of Siberian Chiffchaffs ringed at SML since December 2014 into a thumbnail gallery, which can be accessed here:

https://earlywormringing.wordpress.com/wintering-chiffchaffs/

Back again! Friday 11th January 2019

kyd 418 1

Siberian Chiffchaff 11th January 2019

The welcome arrival of a stable anticyclone over the UK and ideal weather conditions for ringing coincided almost exactly with a debilitating back injury, which also pinched the nerves to my right arm and confined me to the house for the next two and a half weeks! However, by the 11th, cabin fever had got the better of me and I felt up to driving to South Milton and getting a few nets up. The discomfort was tolerable and my worries about reduced mobility proved groundless. The birds cooperated as well, arriving in the nets in a steady trickle and managing to remain relatively straightforward to extract. 40+ birds processed in four hours is just one every 6 minutes and I can manage that pace all day.

In the event Chiffchaffs dominated the catch, making up 31 of the 41 birds trapped. This equals the previous winter Chiffchaff record set on January 26th last year. One of the birds was a classic Siberian Chiffchaff and there was at least one more, un-ringed bird present, which avoided the nets. Maybe next time! Final totals were: Blue Tit 2, Cetti’s Warbler 1, Chiffchaff 30, Goldcrest 1, Long-tailed Tit 2, Robin 2, Siberian Chiffchaff 1 and Wren 2.

In addition, there were 13 buzzards displaying over Horswell Wood, 11 Teal flushed from Ham Ditch and 3 Water Rail present. Reassuringly, after two very quiet years, at least two male Cetti’s Warblers were singing from opposite ends of the ringing area so fingers crossed for a more productive year.

Friday 26th January 2018

JPA984 tristis

The first of three Siberian Chiffchaffs trapped on 26th January 2018

At last, a dry day with winds, which were low enough to get some nets up. In fact, at times in mid-morning it felt positively balmy. The sunny periods were enough to produce swarms of midges, whirling about in mating dances on the leeward sides of taller trees and a north-westerly breeze drifted them towards the net ride beside the sewage treatment plant. Things were looking good for decent numbers of Chiffchaffs. These midges are a major component of their winter diet, often turning their droppings black, when the midges are swarming. When the sun goes in the midges disappear and the warblers disperse making them harder to trap.

JPA971 tristis

The second Siberian Chiffchaff

In the event, the morning’s tally of 47 birds included 30 Chiffchaffs, 4 Firecrests and 2 Goldcrests. Three of the Chiffchaffs showed all of the characteristics of tristis and two of them obligingly gave the characteristic short “peep” call when released.JPA 978 tristis

 

Wednesday 10th January 2018

A lovely day but not many birds.  Just 14 new birds were ringed including: 5 Chiffchaff, 3 Firecrest, 2 Goldcrest and 1 Reed Bunting.

Also on site: another 20+ Chiffchaff, 1 Siberian Chiffchaff, 2 Redwing, 5 Water Rail, 1 Sparrowhawk, 1 Tawny Owl and 1 Great Spotted Woodpecker. There were 3 Hares in the middle of the field to the south of the reedbed and a weasel ran across the footpath by the sewage treatment works.