Getting collared by a goose

Geese are one a special group of birds that can divide people's opinion in the same way that city pigeons or urban gulls can. Many assume that geese stay in the same place year after year, especially the ones that are fed in parks and urban areas. No one really knows for sure however and ringing is uniquely set up to be able to find this out.

Canada Geese taken by John Harding

One particular issue people have is that when geese moult during June or July, they drop all their flight feathers simultaneously and become flightless. Due to the fear of predation they remain very close to bodies of water for the month or so while they regrow their feathers. Geese can cause serious habitat degradation in certain locations like the reed beds at Hickling Board, Norfolk (.pdf) and understanding more about the reasons behind this can improve the situation for geese and people.

On our BTO Nunnery Lakes reserve, Thetford, Norfolk we have several fishing lakes and the geese usually choose the lake that has fencing around it. The downside of this decision is that the geese quickly eat all the accessible food and they have to be moved out onto another lake. During this process the geese are ringed, and in 2012 our ringers started to add uniquely coded plastic neck collars to Greylag and Canada Geese as part of the Hickling Broad project.

Canada Goose AEL - taken by Neil Calbrade

Neck collars are a safe marking method for large geese and have been used widely in previous studies on species such as the migratory Pink-footed Goose and White-fronted Goose, allowing individuals to be identified when on water as well as on land. This is particularly important if you are investigating moulting birds, where seeing their legs are an issue. Due to the size of the goose's head the collars actually have quite a lot of room inside to move around.

Greylag FHA bringing up the next generation - taken by Janet Foster

Since 2012, we have had a fantastic response from BTO staff, volunteers and members of the public who have submitted sightings of any geese with neck collars to www.ring.ac, specifying the species, combination on the colour ring, location (ideally with a grid reference) and the date.

The map below shows the sightings that we received between summer 2012 to summer 2014 away from the reserve itself. As you can see they did indeed go into town but also they explored the surrounding waterways and lakes.




What is amazing however, is after the summer of 2014 the geese were spotted much further away from the BTO reserve, see map below. The reason for this are under investigation and some individuals regularly return to the BTO after making these 'unusual' movements. Being able to identify each individual on the water should help us answer some interesting questions like 'do geese moult in the same place every year', 'do they winter in the same locations' and 'why do they move'.




If you do see a neck collared goose, please report it via www.ring.ac and you will receive information on the movements of that particular goose and at the same time increase our understanding of these birds.

The Goldrush

With all the excitement of the Yellow-browed Warbler influx at the moment, from Shetland to Cornwall, it could be easy to overlook the fact that Goldcrest is also doing very well (see the reporting rates on BirdTrack below). Weighing about 6g, this tiny bird was thought to ride on the backs of Woodcock to our shores (as they arrived at a similar time to Goldcrest) from Scandinavia and the Continent because they wouldn't be able to make it on their own; hence the old name of 'Woodcock pilot'. We now know this is not the case and they can make these massive migrations all on their own.

Ringers all over the country have been catching large numbers of Goldcrest with 150 ringed at Landguard Bird Observatory and 485 ringed at Spurn Bird Observatory over the last three days. This would be a small fraction of the number of birds actually moving through, as the 1,000+ estimate at Gibraltar Bird Observatory on one day can testify.

We have heard that a few have been caught wearing rings from different countries, for example the Mid Lincs Ringing Group caught a Goldcrest ringed in Denmark and a Polish-ringed bird was caught by Tees Ringing Group and Sandwich Bay Bird Observatory caught a Dutch and Latvian ringed Goldcrest. Mike Marsh and his team from Orfordness Nature Reserve managed to catch 109 Goldcrest last Sunday (11 Oct) and one of them was ringed on 6 October at Falsterbo Ringing Station, Sweden! Amazingly, the ring number was TM3052, which, if you put this as a grid reference on an OS 1km map, is only 15km from where the bird was caught. We don't believe this Goldcrest was pre-programmed to go here!

Goldcrest from Sweden. Image of ring taken by several photos of ring merged. By Dave Crawshaw

There are bound to have been more foreign Goldcrest captures over the past few days so feel free to share your stories below in the comments box.

Phylosc's, Acro's and lovely lady Sylvia

Adam Homer writes:

The numbers of warblers ringed at Stanford Reservoir, Northants has increased significantly over the last 5 years. An annual habitat management plan allows us to control tall scrub which then allows low scrub and vegetation such as Brambles, Hawthorn, Sedge and Phragmites to regenerate. This as we all know is very important habitat for breeding birds such as warblers.

A site that is as far inland from any coastal observatory that you could get, Stanford Ringing Group prides itself on the numbers of warblers caught annually. Over 3,600 warblers were ringed in 2014 and already this year we have ringed nearly 3,800 and we still have October to catch a few more Blackcap and Chiffchaff.



With all these warblers ringed and eventually setting off on their migration we do receive a few reports of birds controlled (caught by another ringer >5km from ringing site) and we occasionally control birds ringed at other sites. Every spring we also retrap some of our returning warblers and to me that is what bird ringing is all about. That a small bird such as a Garden Warbler or Willow Warbler can fly a round trip of 3,000 miles and return to the site it has been breeding at for 10 years in a row is amazing!

Garden Warbler taken by Lee Barber (tail obscured)

One of these record-breakers was once again retrapped this year. It was a Garden Warbler that was ringed as an adult female on 2 July 2005. She then disappeared for two years, returning in 2008 and retrapped every year since. I was on holiday when she returned this year and was caught during two of our CES sessions. On 8 August she became the longest known BTO-ringed Garden Warbler at 10yrs and 37 days, breaking the longevity record for this species by 7 days*.

			Year
	2011	2012	2013	2014	2015
Garden Warbler	84	42	66	108	116
Blackcap	710	205	402	1665	1608
Lesser Whitethroat	50	26	56	81	109
Whitethroat	491	261	480	455	469
Sedge Warbler	259	67	145	140	190
Grasshopper Warbler	17	3	2	1	1
Reed Warbler	287	87	242	246	314
Willow Warbler	192	224	178	215	215
Chiffchaff	379	178	388	717	741

 

As you can see from the table above, the numbers of warblers, particularly Blackcap and Chiffchaff, have increased significantly with Garden Warbler and Lesser Whitethroat also showing a positive upward trend.

*Eds - The longevity records will be updated when all the 2015 data has been sent to the Ringing Scheme and fully processed. This longevity record will then replace the previous longevity record... unless another ringer catches an older bird or Stanford Ringing Group catch this Garden Warbler again a few days older.

Exceptional Siskin Surge

The Siskin movement this autumn has been exceptional, for both the early start and vast numbers involved, as indicated by BirdTrack. With the peak movement and arrival of continental birds still to come, numbers in the UK are expected to increase considerably.


BirdTrack Siskin reporting rate

Jeff Kew from Thetford, Norfolk writes:

This has been an exceptional September for Siskins in the UK, with large numbers being reported across southern Britain, due to a major irruption from Northern Britain.

Last autumn Siskins were fairly scare in Southern England with a few being reported on feeders in February and March, the usual peak time to see and ring this species. Reports from Scotland indicate a bumper cone crop last summer and consequently most Siskins stayed at home for the winter, this Autumn with dwindling food supplies the picture is very different.

In the Norfolk / Suffolk Brecks area we have not seen anything like the numbers coming to feeding stations in September since 2005.

In our Thetford garden we have already ringed 611 Siskins this month (in just 4 ringing sessions), with an amazing 368 caught on the 18 September.

One of the hundreds of Siskins recorded taken by Jeff Kew

We have had birds ranging from exceptionally light (10.4g) to exceptionally heavy (17.0g) - which presumably indicates a mix of recently arrived birds and birds with serious intent to travel much further south. The majority are juveniles, which appear to have done less post juvenile moult than our local breeders.

Post juvenile moult strategies are interesting with the amount of post juvenile moult being variable and probably linked to both fledging date and food supply. We believe unmoulted juveniles (3JJ) can reach us from Scotland.

Thinking back to what we saw in 2005 we had high numbers through September, followed by two recoveries in Spain in Navarra and on Mallorca - which could give an indication of where some birds of this years birds may end up this winter.

Greg Conway from Thetford Forest Ringing Group writes:

The extent of post juvenile moult is highly variable, with some typically retaining one, or more, old greater coverts along with juvenile tertials and tail feathers, whereas others replace all coverts, tertials and tail (see below).  However, there are also many in between that replace different numbers of tertials and tail, often symmetrically but not always centrally!

Juvenile Siskin with replaced greater coverts, tail and tertials - Greg Conway

Juvenile Siskin with replaced greater coverts and two inner tertials - Greg Conway

Juvenile Siskin that has replaced outer pair and 2 central pairs of tail feathers contrasting with juvenile feathers (pointed and browner) - Greg Conway

To better understand the mix of different migration and post juvenile moult strategies occurring this autumn, and add to long-term data collected from Thetford Forest, ​any ringers catching Siskins are encouraged to record the following biometrics (in addition to age/sex, wing & weight):

All birds if possible!
1) Number of unmoulted greater coverts (including those with zero)
2) Fat score (0-8 scale)​

And if time allows!
3) Tertial moult (record in IPMR moult card)
4) Tail moult (record in IPMR moult card)
5) Pectoral muscle score (0-3 scale)

Nettlecreeper doing more than creeping

Mike Marsh writes:

On 4 July we controlled a German-ringed Whitethroat at Orfordness, Suffolk. The ringing information showed that this bird had been ringed earlier in the spring on the island of Helgoland, Germany and when I checked against the Online Ringing Reports I was surprised to find that this was only the second ringing movement of a Whitethroat between Germany and the UK, the other being in 1952.

Although it is hard to work out why a Whitethroat should be moving from Germany to the UK at this time of year it is interesting to note how similar the movement of the bird was to the one 63 years earlier. Both birds had been ringed off the NW German coast in late April/early May and then controlled in East Anglia in late June/early July, and the movements were 483km/WSW/54 days compared with 468km/W/59 days.

German ringed Whitethroat by Dave Crawshaw and several photos of the ring that have been merged to see full ring number

Ring number - 90212927
11-05-2015   ringed: Helgoland, Helgoland, GERMANY  54 10’N  07 55’E
04-07-2015   controlled: Orfordness, Suffolk  52 05’N  01 34’E
                         483 km WSW  -  54 days

Ring number - 9435010
29-04-1952   ringed: Wangerooge-Ost, East Friesland Islands, GERMANY  53 47’N  07 58’E
27-06-1952   controlled: Cley-next-the-Sea, Norfolk  52 57’N  01 03’E
                         468km W  -  59 days

Eds - Nettlecreeper is a local name of the Whitethroat. 'Controlled' is when a ringer catches a previously ringed bird, usually that he/she hasn't put on originally.