2024 Report

The 2024 SNRG Report is now published and available. If you would like a copy, please email the address at the top of the 'Reports' page - see tab at the top.

 

Allestree Park Bird Boxes – Friday 28 February

As part of the continuing bird monitoring at Allestree Park Rewilding, I had organised for the
inclusion of nest boxes on the site. On Friday, I met up with Jim and Sandra to install eight large nest boxes targetting birds of prey. These included two for Barn Owls, two for Kestrels and four for Tawny Owls. It may be too late for them to be used this year, but their longevity will hopefully allow increased nesting opportunities for these birds in the future. Monitoring these boxes will provide insights into predators around the park. The implementation of this project would not have been possible without the generous funding from Derby City Council, and Jim for constructing the boxes.

Josh

 

Brackenhurst - Sunday 2 March

A session at the Brackenhurst feeders on Sunday produced 45 birds. Yellowhammer was the most numerous species, and the catch included a male (pictured below) originally ringed in March 2020 as a 5. A flock of 4 House Sparrow were the first ringed on site since 2022.

The catch breakdown was as follows (new/retrap): Yellowhammer 16/1, House Sparrow 4/0, Dunnock 0/5, Blackbird 1/0, Blue Tit 3/6, Robin 0/2 and Great Tit 0/7.

Rowan

Broomfield Winter CES Visit 8 - Sunday 9 February

The final winter CES visit was made to Broomfield today, although it will not be the final ringing visit to the site this winter. As usual the weather forecast was wrong and we arrived on site in rain and with more of a breeze than forecast, but fortunately the rain stopped by the time we had set the first nets. 

We set the usual feeder nets and the Redwing nets, but were not expecting to catch any Redwing as they do not respond well to calls from sound lures late in the winter. There were however good numbers of Redwing and Starling feeding on one of the sports fields along with a couple of Mistle Thrush. 

The feeder nets caught the bulk of the day's catch which totalled 43, comprising: 12 Blue Tit, 3 Great Tit, 16 Long-tailed Tit, 3 Robin, 5 Chaffinch, 3 Blackbird and a surprise single Redwing. We also caught a single Bullfinch but we released it without a ring because it had scaly legs. 

The breeze increased as the morning progressed so all in all a good catch considering the conditions. Overhead we had Buzzard, Sparrowhawk and a decent flock of Lapwing.

Kev

 

Reed Pond Ringing Session - Saturday 1 February

Following a couple of site visits to the Reed Pond Nature Reserve in Lambley, it was agreed that South Notts Ringing Group would hold a ringing session there on 1 February 2025. Whilst I don't think the site lends itself to regular bird ringing, a demo session was useful as it allowed us to collaborate with another local wildlife group, with several of their members visiting on the day, and it possibly helps with their understanding of the birds on site.

After the initial visit, when there didn't seem to be too many birds on site, the volunteers have since established a couple of bird feeders, so as we arrived there seemed quite an encouraging amount of activity and bird song.

We put up three mist nets which resulted in a catch of 37 birds, thanks to the feeders, comprising:
13 Blue Tits, 6 Great Tits, 9 Long-tailed Tits, 3 Chaffinches and single Robin, Dunnock, Woodpigeon, Blackbird, Song Thrush and Kestrel.

Many thanks to the Reed Pond Nature Reserve and the people who came along.

Mick Pearson

 

Brackenhurst Winter CES Visit 7 - Sunday 2 February

On Sunday, the seventh winter CES visit was completed at NTU Brackenhurst. The 3 feeder nets produced a total of 51 birds. This included 15 new Yellowhammers, which seem to have been thin on the ground this winter with just one caught the previous visit. Some of the first year Yellowhammers showed obvious fault bars, like the bird pictured below with a fault bar across the greater coverts.

Totals were as follows (new/retrap): Yellowhammer 15/0, Blue Tit 3/14, Great Tit 3/5, Robin 2/3, Blackbird 3/1 and Dunnock 0/1.

Rowan

Swans

On Friday 31 January, six members of SNRG went to Codnor Park Reservoir with the intention of ringing the 5 cygnets there. We succeeded and we also managed to catch the adults so they were ringed too. Unfortunately, I was unable to obtain permission to colour-ring the birds, but hopefully the metal rings will be read in the future so we know where these swans end up. 

Many thanks to Cromford Canal and Codnor Park Reservoir group (who kindly donated money for the swan rings) and to Codnor Park Fishery.

Mick P

 

Broomfield Winter CES Visit 7 – Saturday 25 January

Another frosty morning at Broomfield as we set the feeder nets and a few others, plus some traps. The clear skies meant the sun was soon shining on some of the nets, particularly the Redwing net which failed to catch any Redwing. In fact the feeder nets caught all but 3 of today's birds as the rest of the site was very quiet. Thankfully the feeders were fairly busy, although the majority of the birds caught were tits and retraps, much the same mix as being experienced at our other CES site at Brackenhurst. We finished with 38 birds as follows: Blue Tit 14, Great Tit 4, Long-tailed Tit 6, Robin 4, Dunnock 5, Chaffinch 3, Blackbird 2.

Kev

Broomfield Winter CES Visit 6 - Sunday 12 January

Kev H, Gary, Josh, Laura, Kev B and I made the sixth Winter CES visit to Broomfield College. We had nets up by the feeders and sports field, as well as a net and spring traps in the orchard, two nets by the allotment and a walk-in trap for Starlings.

The ground was frosty as we’ve experienced sub-zero temperatures all week, and we were expecting a good catch by the feeders as birds would be hungry in the cold conditions. Although we came back with birds every net round, the numbers weren’t as high as we’d hoped.

The spring traps baited with apple in the orchard did well at catching Robins and a nice continental female Blackbird. However, the walk-in trap baited with mealworms for Starlings remained empty. On two previous visits, flocks of 50+ Starlings had been seen nearby but only a handful were seen going over the base late in the morning.

Armed with mealworms and misplaced optimism, we moved the walk-in trap to the car park in the unlikely effort to catch a Pied Wagtail, and needless to say, success eluded us.

We caught a total of 38 birds, including 21 retraps, comprising: Blue Tit 12, Redwing 6, Robin 6, Great Tit 5, Dunnock 3, Long-tailed Tit 2, Blackbird 2, Wren 1, Goldcrest 1.

Thank you to Josh who brought some very tasty homemade blueberry mini muffins. 

Holly

 

Broomfield supplementary visit – Saturday 4 January

A cold frosty morning on Saturday, but overcast and still, which is perfect for mist-netting. Some investigation work had been carried out over the holidays to find why the fat balls we were putting out were all disappearing quickly after the feeders had been filled and this resulted in the culprits being identified. It was Jackdaws that were emptying the feeders in double-quick time, so a quick modification was made to the feeders to deter them, which as of today seems to working. 

No doubt the cold weather had made more birds head to the feeders and the result was the best catch of the winter in the feeder nets, including 7 Robins. A Woodpigeon in the net was a new species ringed at the site. A Great Tit showing unusual moult limits was captured, the fourth bird I have seen this autumn/winter having never seen it before. The bird had been ringed as a 1st winter bird in November 2023 so was of known age and should have had a full moult after breeding in 2024 but for some reason failed to moult all of it's primary coverts. 

We ended with a catch of 44, 42 of them from the feeder nets which is the best catch of the winter so far at these nets. The catch comprised: Woodpigeon 1, Dunnock 4, Robin 7, Redwing 2, Long-tailed Tit 10, Coal Tit 1, Blue Tit 7, Great Tit 11, Chaffinch 1.

Generally there were quite a few birds around including a Kestrel, but few winter thrushes again.

Kev

Wood Pigeon (KJH)

Unusual Great Tit moult, a bird born in 2023 with some retained juvenile primary coverts (KJH)

 

Broomfield Winter CES Visit 5 – Sunday 29 December.

More bad weather meant we had not visited for two weeks when we held a ringing session on Sunday. There seemed to be a little more bird activity at the site and we had a slightly better catch the compared with the previous visit. All the small hanging feeders had been emptied within three days, so something is busy feeding there. We had a catch of 18 birds made up of: Dunnock 1, Robin 3, Redwing 1, Coal Tit 1, Blue Tit 7, Great Tit 4, Chaffinch 1.

Other birds around were the Ravens, a few Redwing and a Red Kite passed over quite low. After the fog of the previous few days the sun was out and it was quite warm, this no doubt was what prompted a Mistle Thrush and Blackbird to burst into full song.

Kev

Brackenhurst Winter CES Visit 4 - Friday 27 December

Today was the fourth winter CES visit to the NTU Brackenhurst site. It was a calm and misty morning resulting in 51 birds, of which 32 were retraps. We had the usual feeder nets and then two extra nets in the field with a Redwing sound lure. These nets caught 3 new Redwing, a new Song Thrush and a flock of Long-tailed Tits. At the feeders we caught mainly retrap tits, mostly adults. This is the same as previous visits and the lack of first-year birds is worrying.

The highlights were a Song Thrush and a few large Blackbirds. We also caught the third Jay of the winter. This isn't regular for Brackenhurst, with 5 being caught in 2021 and 2 in 2012.

The catch comprised (new/retrap): Long-tailed Tit 5/2, Great Tit 2/7, Blue Tit 0/13, Robin 0/4, Dunnock 3/5, Redwing 3/0, Song Thrush 2/0, Blackbird 3/1, Jay 1/0.

Alex T

Long-tailed Tit

Jay

 

Recent recoveries

This post is to summarise some of the recoveries of ringed birds over the course of 2024.

One of our redwings ringed at Trowell in December 2022 was recaught in Tauvo, Finland in
September 2023. This is a distance of 1973 km.

A Blue Tit initially ringed by Sorby Breck Ringing Group near Longshaw, Derbyshire, has been
recovered twice by us in Longford, Derbyshire. At over 600 days and 41 km between ringing and
recapturing, this Blue Tit has travelled quite a distance for usually sedentary birds.

The group’s Goldfinch colour-ringing project had its first success. A Goldfinch was identified by the
unique colour ring code by a member of the public just 1km from where it was ringed in Carlton,
Nottinghamshire.

A Reed Warbler from Skylarks in August was recovered by Titchfield Haven Ringing Group in
Hampshire, having travelled 237 km in just 12 days.

During the CES at Attenborough, we retrapped a Reed Warbler, which had been ringed last August at Stanford Reservoir in Northamptonshire.

A Chiffchaff ringed at Skylarks Nature Reserve in July 2024 was recaught in Sandwich, Kent two months later.

A Garden Warbler ringed in Icklesham, Sussex in August 2023 was recaught by us at Skylarks in July. 

Sand Martin ringed as a chick in Rutland in 2022 was found dead at the Sand Martin colony at
Attenborough in May 2024.

A Cormorant that was colour-ringed in the nest in April 2019 was resighted in August of this year,
back at Attenborough Nature Reserve. Cormorants can move around the country extensively, but
tend to frequent familiar sites as they travel.

Two Black-headed Gulls have been resighted at Trent Bridge by the group, one in February and one
in March. One was ringed in Frognerkilen, Norway in August 2019, and the other in Kalvia, Finland in 2002.

Also resighted at Trent Bridge in February was a Mute Swan, which had been ringed in October 2022 in Manchester by the Loganhurst Ringing Partnership.

A brood of four Peregrine chicks were colour ringed near Langford, Nottinghamshire this May. In
July, one of them was identified sitting on a pylon near Newark, a 12km distance.

Josh

Colour-ringing a Peregrine chick

Finding evidence of eccentric moult in historic specimens

As touched on in my previous post about eccentric moult, it seems to be a firmly held belief that
young birds are undergoing a more extensive post-juvenile moult than they used to, and that
this is a result of climate change.

While we are looking closely at the Goldfinches we catch, we cannot know if they are doing
more moult now without first knowing how much they did in the past. To gather data on this, we
are visiting natural history collections to study their specimens and complete moult score cards.

In October, Josh and I visited the National History Museum in Tring. It houses the largest
collection of bird skins in the world, with over 750,000 skins from 8,000 species, representing
95% of all species on Earth. However, we’d gone specifically to look at their collection of 112
British Goldfinches (Carduelis carduelis britannica).

Nearly all of the birds we handled dated from the mid-1800s to mid-1900s. The oldest bird we
studied was from 1824. They had been carefully preserved, some using arsenic and lead, and
so we handled them with extreme care.

Surprisingly, we did find evidence of eccentric moult in two birds! One bird had only replaced
P6, another had replaced P5 and P6. Two other specimens appeared to show evidence of a
descendant moult, though it was difficult to determine the age of the inner primaries given that
the wings had been fixed in a closed position. The best we could say with any accuracy was
that these two birds had moulted P4-P7.

We didn’t expect to find any evidence at all so to find four examples, all from the 1800s, was
quite a surprise. We will continue visiting more collections to increase this data set.

Thank you very much to the curator, Mark, for organising our visit and encouraging us to come
back.

Holly

 

How to spot eccentric moult in Goldfinches

This year, we wanted to get to the bottom of whether juvenile Goldfinches were undergoing an eccentric or descendent primary moult. Eccentric moult is when only a few central primaries are replaced, compared to descendent which follows the usual moult pattern by starting at the inner primaries and working outwards.

Svensson 5th edition says that “A few British juveniles and a higher proportion from more southerly populations moult tertials, tail feathers, and one or several central primaries in Autumn.” It also gives the juvenile moult strategy as “Young: sp; (SC-)”, with the hyphen after SC indicating that any complete moult is typically arrested. If some birds may be starting a complete moult, while others replace only a few central primaries, we could be looking for birds with either an eccentric or descendent moult pattern.

There are a number of features that we can look for:

• vibrancy and shape of the yellow outer web
• brightness and shape of the white terminal dot
• black glossiness
• wear on the tips 

Let's look at some of these variations in detail -

Above: Age 3, Moult P.
This is a typical juvenile wing showing no primary moult. You can clearly see that the yellow webs are dull, all the tips are buff, and the white dot is concave in shape. However, there is a lot of variation so it’s worth comparing this with one that is a bit more tricky.

Above: Age 3, Moult P.
This is also a juvenile wing showing no moult. But you can see that the yellow is much brighter, the black background is glossier, and the white dots have less buff. However, these features are consistent across the whole wing - there’s no difference in yellow between one feather and the next, the angle of the yellow tip even, wear on the tips is even, the white dots are all concave, and the black gradually fades to brown on the outer feathers as we would expect.

Above: Age 3, Moult F, Moult score 0000550000.
This is my most obvious example of a juvenile showing eccentric moult. The difference in the brightness of the yellow is clear to see on P5 and P6. There’s a big difference in wear on the tips with P4 being frayed and P5 being completely fresh. Between P6 and P7, you can see a step change in the black background as P6 is glossy and P7 is faded. However, again, not all are this easy so let’s compare…

Above: Age 3, Moult F, Moult score 0000550000.
This is my most subtle example. With no active moult, and no difference in colour across the wing, you can see how this would be easy to miss. But anyone looking out for eccentric moult will notice the difference in wear on the tips of P4 and P5. If you look even closer, the new P5 and P6 have a less acute angle on the yellow tip, giving them a slightly blunt ended appearance in comparison to the others. Arguably, the yellow web on P5 and P6 is also longer.

Above: Age 3, Moult F, Moult score 0000550000.
Beware the black background! This is another subtle example, and a warning against using the black background as a key feature. If you recall the first two photos of birds that weren’t showing any primary moult, the black background gradually and naturally fades from dark and glossy on the inner primaries to faded brown on the outer primaries. This bird has replaced P5 and P6, but there is no difference in black glossiness between the old P4 and the P5, which may lead the uninitiated to miss this moult entirely, or to assume it was descendent. The change in black from P6 and P7 is visible, as we would expect. However, if you look at the wear you can clearly see a difference in age between P4 and P5, and now that you know what to look for, you can see that the yellow web is more rounded on P5 and P6 too.

I advocate using all the features to reach a conclusion. Wear on the tip is the most reliable as it doesn’t vary between birds, unlike shape, vibrancy and glossiness.

Out of 268 Goldfinches I’ve caught in the garden this year, 15 have completed an eccentric moult, which is 5%. Jenni and Winkler say in ‘Moult and Ageing of European Passerines’ that 3-4% of British Goldfinches undergo a complete moult, but I am yet to be lucky enough to find evidence of that!

Why this is important

You may be wondering why any of this matters. It is, after all, only a couple of replaced feathers. But it is important to record eccentric moult accurately because:

• At worst, some ringers may misidentify active primary moult as the main moult completed by adults. This means that they would incorrectly age juveniles as adults which affects national data.
• Other ringers may assume the primary moult is descendant rather than eccentric, and they record inaccurate moult scores. This gives a false indication of the extent of post-juvenile moult. As everyone keeps talking about how birds these days are moulting more because of climate change, it’s more important than ever that we collect accurate data to evidence any change.
• For juveniles that have completed an eccentric moult, it is very easy to miss the newly replaced feathers from Autumn onwards. This means that the number of birds that undergo an eccentric moult is not accurately recorded.
• The scientific journals on eccentric moult are out of date. British studies were last conducted in the 1980s, and more recent studies were undertaken on a different subspecies of Goldfinch on the Balearic Islands. If birds have changed in the 40 years since these papers were published, it means that the field guides are out of date and we need to be looking more closely at birds when they are in the hand.

If nothing else, I hope this analysis helps you to appreciate the variety that can be found in a very common garden bird if you look hard enough.

Holly