Marsworth, Autumn is upon us.

After a week of wind and rain we grabbed the chance to go out on Wednesday even though it still looked fairly breezy. We put up a few nets in the more sheltered eastern corner of the site and a new net between some hazel trees. I had planned to fill the time with some scrub clearing but it was a busier morning that expected with that interesting mix of the last summer migrants and autumn visitors. We started with Chiffchaffs and Blackcaps and then a flurry of Goldcrests came to the tape lure along with four Bullfinch.

The new net was a success and caught four Lesser Redpoll, a new species for Claire, plus a Chaffinch. The Chaffinch was a young male that had unusually moulted all the secondaries and a couple of primaries on one wing Given the terrible condition of the feathers on the other wing it was likely that he had had to replace similarly damaged feathers. 

Juvenile Chaffinch with new secondaries on right wing compared with tatty feathers on left wing.

All the Redpolls were juveniles, aged according to the shape of the tail feathers and a moult limit along the greater coverts. None were showing any red feathers on the breast so we could not sex them.

Redpoll wing showing 6 old greater coverts

Lesser Redpoll

The last bird of the day was a new Great Spotted Woodpecker which was still moulting its primaries as part of its post juvenile moult. The contrast between the black lesser coverts and the duller greater coverts plus the good condition of the unmoulted outer primary, aged the bird as a juvenile. Its body moult was nearly complete and there were just a few little red feathers left in the crown but the new bright red nape patch means this is a male.

Greater Spotted Woodpecker wing. 

The bright red nape of a male Greater Spotted Woodpecker with just a few red juvenile feather left in the crown.

We finished with 56 birds (11 retraps/45 new)

Bulbous Honey Fungus on dead willow

Marsworth 27th and 29th October - Faulty feathers

Two very different days ringing just two days apart.
Friday was beautiful weather, sunny and calm, so I took the opportunity to get out and tried a new net near the nyger seed feeder that I put out last week. Nothing seems to have found the feeder yet but it is still a nice position for a net at the edge of the trees in the low willow scrub. The Redwing tape brought in a few individuals and I also caught the first Redpolls of the year; we generally only catch Redpolls in October and November when they are passing through. The new net also caught a new Great Spotted Woodpecker with quite dramatic fault bars across his flight feathers. Fault bars are  caused by an interruption in nutrition while the feathers are growing and when the fault lines up across the feathers like this they indicate that the feathers all grew simultaneously. Fault bars are not unusual in juvenile birds.

Great Spotted Woodpecker with pale fault bars across unmoulted secondaries and primary coverts.

There were some interesting fault bars to be seen on other birds as well as the woodpecker. An adult Blue Tit had a fault bar across three of his tail feathers, it looked as though he had replaced his tail as part of the normal post-breeding moult and then had to replace three feathers from some accidental loss. Why the replaced feathers had a fault bar is curious - perhaps he had a near miss with a sparrowhawk and had been below par in his foraging for a few days? In any case it was a good example of how a fault bar can be present on adult type feathers.

4M Blue Tit with fault bar across three feathers

I also caught a new control Cetti's Warbler that was ringed at Rutland Water in June as a 3J. This bird had very poor feathers. The primaries were extremely tatty and the tail had some of the feather tips completely broken off apparently caused by a combination of fault bars and feather mites. Five of the feathers looked as though they had already been replaced and it will be interesting if we retrap this bird to see if she carries on replacing tail feathers as necessary.

Juvenile Cetti's Warbler from Rutland Water

Thankfully the hornets have largely disappeared now that there has been some colder weather, I spotted one later on in the morning when the temperature rose which hurried me into taking the nets down. I have had enough of cutting nets to release them!

After the pleasant day on Friday the weather on Sunday was very different. The forecast had been for breezy weather but when Gabor, Chris and I got there at 06:30 it was more like 25mph. We stood around for a while trying to decide whether to bother but the wind started to drop so we put a few nets up in the more sheltered areas. We managed to get five nets up in the end and caught Goldcrests, two more Redpolls and four Chiffchaff. We tried a hopeful tape lure of Hawfinch call following numerous sightings of Hawfinch passing over in the last week but no luck. A few Goldcrests, a Bullfinch and a Long-tail Tit flock of mainly retraps brought the total for the day up to 33.

Lynne

Marsworth 24th September 2017 - some fat Blackcaps

Marsworth
Warm, calm at first becoming breezy
06:00 - 11:00am
Tapes playing - Blackcap on one 60' net and the german Chiffchaff/Goldcrest/Yellow-browed Warbler mix from Chris at the double net (100').

I also put a couple of nets around the hopper which was where the reed buntings were caught.

SPNAME	Row Summary	New Bird	Retrap
Blackbird	1	1
Blackcap	19	18	1
Blue Tit	3	2	1
Chiffchaff	6	6
Goldcrest	2	2
Great Tit	1	1
Reed Bunting	8	5	3
Robin	2	1	1
Wren	1	1
Total	43	37	6

There were only 6 retraps and one of them was a male Blackcap ringed 20/04/2011 and last trapped in June 2013. 

Quite a few of the Blackcaps are now carrying fat, There were two very fat ones (Fat 6+) weighing in at 22.5g and 23.2g, plus a couple at Fat 5 (around 20g). There was also a Chiffchaff at Fat 4, weighing 8g. One of the Blackcaps had a very mottled head with unusually wide brown fringing to the feathers (see photos).

I caught 8 reed buntings, only one already had colour-rings so another seven were colour-ringed bringing the total up to 33. Hopefully we will be able to re-sight these over the winter. One of the retrap female Reed Buntings was still in main moult.

A Goldcrest still in post-juvenile moult was replacing just the two innermost greater coverts.

There were two Cetti's Warblers singing and Robins singing autumn song. The  Hobbies are still here; I must have disturbed them when I arrived because they started calling from the trees above the reed bed in the dark.

Lynne

 Male Blackcap with brown fringed head feathers

Marsworth - Tapes playing and tricky Chiffchaffs

Marsworth
Summary of three sessions in September
03/09/2017 LL, KB, CK
10/09/2017 LL & AM
15/09/2017 LL & AL

We have had three sessions at Marsworth using tape lures, mainly Blackcap and Chiffchaff song with a bit of Willow Warbler, Goldcrest and also tried Redstart (must have been feeling optimistic).
The weather has been quite poor over the last couple of weeks with strong winds and a fair bit of rain but the birds seem to be in good condition. The adults and most of the juveniles have completed moult although we are still getting a few late 3J Wrens and Chiffchaff. With moult mainly over it is starting to get harder to pick out the adults from the juveniles - see below for a couple of photos which show how careful you have to be!
In the latest session today we started to get a few more birds carrying some fat but nothing higher than F3. The Willow Warblers and Reed Warblers are few and far between now but there is no sign yet of any of the autumn migrants such as Goldcrest.
We have been treated to the displays of 4 Hobbies over the ringing site.

Species	Total Summary	unaged	3	3J	adult
Blackcap	94	3	80	4	7
Blue Tit	5		5
Bullfinch	1			1
Chiffchaff	73	1	62	9	1
Dunnock	1				1
Goldcrest	2		2
Great Tit	7		7
Long-tailed Tit	5	5
Reed Bunting	12*				12
Reed Warbler	3		3
Robin	5		4		1
Treecreeper	1		1
Willow Warbler	2		2
Wren	12		6	6
Total	223	9	172	20	22

Here are two photos of known-age Chiffchaffs which show that they are not always easy to age!

This juvenile had quite rounded tail feathers (juvenile tail feathers are usually more pointed than adult tail feathers) but it did have 5 OGC visible which helped to age it as juvenile. It is possible that it had replaced the tail but I don't think so because there is a hint of a fault bar showing in the photograph on the left hand side, and possibly T5 has been replaced on the right . 

The adult Chiffchaff had surprisingly pointed tail feathers - the feathers are quite broad and they have the pale grey edging which seems characteristic of adults but it would be easy for this bird to be misaged as a juvenile if you looked at tail shape alone.

Juvenile Chiffchaff KEA648 15/09/2017 (5OGCs)
Originally ringed 29/08/2017 as 3JP 

Adult Chiffchaff JYV145 15/09/2017
Originally ringed 15/05/2017 as 4(M)