11 January 2020

French Shag on Looe Island

Recently we've been going back through some records and making sure that all of the French colour-ringed gulls seen on Looe Island (or more correctly St George's Island) over the years have been processed at the BTO end, thanks to the efforts of Claire the Warden's Assistant. There's been a Great Black-backed Gull colour-ringing project on the island since 2010 and Claire's efforts reading the colour rings are key to the success of the project. More details of the project can be found on the Cornwall Birds website.

But in amongst the gull records was a sighting of a colour-ringed Shag which is pretty unusual in the southwest. Claire photographed the bird by the jetty in December and it turns out it belonged to a French project, perhaps not surprising considering the closest UK projects are in west Wales and southern Ireland. K26 had been ringed as a chick in 2015 on Chausey, a small group of islands off the Normandy coast, geographically part of the Channel Islands group and managed as a bird reserve by the Groupe Ornithologique Normand.

It turns out that this is just the seventh record of a French-ringed Shag to be found in the UK. Of the previous six, three have been in Cornwall, sadly all young birds found dead in fishing nets (in 1982, 1984 and 1985). Of the other three, two were also in the southwest, found dead on the Isles of Scilly in 1981 and in Devon in 1989 (actually ringed 11 years earlier).

The only other record was also from the same French colour-ringing project, of a bird ringed as a chick in 2017 and seen later that year in Sheringham, Norfolk. The project on Chausey has ringed 1550 Shag chicks and remarkably these are the only two birds to have been seen in the UK, with the only other 'international' movements being two birds seen in The Netherlands. It's quite remarkable that these birds don't wander more widely, but know we all know what to look for we can hopefully find some more!

Thanks to Claire on Looe Island for sorting out all the records (and spending hours reading colour rings) and to Fabrice Gallien in France for the information on the birds and the project.

1 January 2020

New Year, new Chiffs

It's been a long time since we've blogged, but what better time to change that than New Year. Today was a rare calm day and despite not being very cold we decided to have a couple of hours at Gwennap Sewage Works anyway. The vagaries of ringing at sewage works is that we often only use the smallest size rings (AA) and today was no exception. In the two hours (and just three nets) we ringed 28 Chiffchaffs, including this very smart tristis Siberian Chiffchaff. Unfortunately we didn't recatch any ringed birds from last winter (when we ringed 44 Chiffchaff here), but once the colder weather arrives I'm sure we'll be catching more.

There were well over 40 Chiffchaff on site (and two Yellow-browed Warblers), so plenty more to keep us occupied on the next calm day. The bycatch wasn't too bad either: Firecrest, two Long-tailed Tits and the obligatory Wren.

11 October 2019

Another German Med Gull

It's been a long time since we've blogged, but having received this photo we had to share. Yellow AZTN was one of 166 Mediterranean Gull chicks ringed in Saxony, Germany this summer. Of those 36 have been seen since, 25 in the UK, so it was nice to see AZTN at Stithians Reservoir earlier in the week.

In total almost 500 German-ringed Med Gulls have been seen in the UK, with just 20 seen in Cornwall. Thanks to Andreas for the quick reply on the sighting and the photo.

6 August 2019

Month-old French Kittiwake at Portreath

Following the depressing failure of the Trewavas Head Kittiwake colonies (see here), it's vaguely encouraging that the colony in Western Cove, Portreath seems to be thriving. A late evening visit to catch up on some nest recording saw a very busy colony, with some birds already fledged.

It was also good to see a nice variety of ringed birds, with a bird from Puffin Island (Anglesey), three from Pont du Raz (Brittany) and also one of our own Trewavas Head birds (VM, ringed as a chick in 2017). It was surprising to see good numbers of loafing birds away from the main colony as well, which we presumed were local birds, but in amongst them were three French-ringed birds we've not recorded before at Portreath. So we did wonder if these were dispersing birds or failed breeders. But we were then amazed to see a recently-fledged juvenile on the cliff with a nice set of French colour rings!

A quick email (and equally quick reply) to Jean Yves Monnat in France and he confirmed that this was Green/Yellow/metal - White/Black/Orange. It was ringed on 28th May at Pointe du Van and took it's first flight on 6th July, then being seen daily until 15th July. It was one of the first juveniles to leave the colony and made a pretty quick movement over to Cornwall, and just goes to show how closely linked these colonies are across the Channel.

So it's always worth casting a glance over Kittiwake flocks at this time of year as you never know what you might find.

15 July 2019

Trewavas Kittiwake failure

A flat calm sea and a day off is the perfect opportunity for a paddle out along the coast, so might as well combine it with dropping in on the Trewavas Head Kittiwakes. It started well, with a new sub-colony (at Trequeen Zawn) holding nine nests, some with good-sized chicks. The first ever resighting of one of our birds ringed as a chick was here in the early days of the colony, as young birds prospect new areas. This held true, with the zawn holding four birds we'd ringed as chicks in 2015 and 2016, one now at a nest with chicks.

PP (ringed as a chick in 2015) with two chicks

There was also a new French bird in the colony, so it'll be interesting to see if this too is a young bird recruiting into a new area.


But as we paddled round to the main part of the colony it was eerily quiet with a dozen or so birds on the cliffs, but these soon left. Early on in the season we were worried that the return rate of ringed adults was low, then we were unable to ring any adults as they hadn't laid, but we weren't expecting a complete failure. So not a single egg or chick at a site that should be holding over 70 pairs!

Thimgs were no better 'around the corner' as well, with the site by the engine houses also deserted, with not a single bird to be seen. This site should hold over 65 pairs.

So with the recent complete failure of the colony at Newquay, that leaves just two Cornish sites holding any number of birds this summer! The site at Western Cove, Portreath is thankfully thriving (250+ pairs) and there are good numbers at Porthmissen, but other than that we have nine at Trewavas and two at Rinsey!

The rare sight of a brood of three Kittiwake chicks (far left), at Western Cove, Portreath

8 July 2019

Final Mullion totals

At the end of last week, a small team of four paddled over to Mullion Island for our last visit of the year, aiming to ring Great Black-backed Gull chicks. Productivity on the island is always poor so it's with trepidation that we land, not knowing how many chicks we'll find.

After a slow start, we finally started to find chicks, although most were single birds. But as we covered the top of the island we found groups of two and three chicks and we ended the evening ringing 16 birds, which is the second highest total since we started marking chicks in 2013.

2013 2014 2015 2016 2017 2018 2019
GBB Gull nests - 62 37 83 70 60 71
GBB Gull eggs/chicks 98 174 90 204 166 - 195
GBB Gull chicks ringed 4 17 12 13 5 3 16
Cormorant nests 24 52 50 39 47 38 47
Cormorant chicks ringed 11 19 7 16 0 0 14

 Having said that, finding just 18 chicks (16 ringed and two which were too big to approach safely) from 195 eggs/chicks earlier in the season is still pretty poor. We did also find four large dead chicks, but it wasn't clear how they'd died. It was also depressing to find a dead adult on top of the island with fishing line and presumably a hook in its throat, anothe victim of our polluted seas.

3 July 2019

23-hour ringing day!

You know it's summer when you're up before 5am to be out ringing gull chicks and then back home at 4am having been ringing Storm Petrels all night!

This last week has seen various small teams out on rooftops around Falmouth ringing gull chicks, all part of the ever-growing project looking at the behaviour and movements of urban Herring Gulls. So far we've ringed 25 birds on St Mary's School, 20 on Tregnoniggie Industrial Estate, 65 on the university campus roofs in Penryn and various other smaller groups.

Ringing chicks on the roof of Wilko in Falmouth

It's was also full moon last night and perfect weather for some Storm Petrel ringing, so a small team headed down to Gwennap Head, Porthgwarra. As the wind dropped the birds started arriving at the nets and we were set for a busy night!

The final tally was 114 new birds ringed and six birds retrapped that weer already ringed. Three of these were birds we'd ringed previously, one just a month ago at Lizard. Another was a bird we ringed at Porthgwarra in July 2018 that was recaught in North Wales just a week later. Another has a slightly more interesting history. It was ringed at Porthgwarra in June 2015, then recaught on Skokholm Island in July 2015 and in Ceredigion 10 days later. In an almost identical occurence it was recaught again on Skokholm Island in August 2018 and in North Wales nine days later!

Other ringed birds came from Co Mayo (ringed in 2008, so a good age), Skokholm Island in 2018 and also a Spanish-ringed bird. This is only the seventh Spanish-ringed Storm Petrel to be found in the UK, but the fourth at Gwennap Head (after birds in 2008, 2009 and 2017)! Others have been caught at Pendeen (in 2005), Tyne & Wear (in 1992) and two in Scotland.

8 June 2019

Breeding season hotting up!

It's been a while since we updated on the start of the breeding season, so this is a quick tour of some of what we've been up to recently. Most recently we've had our first session out ringing Storm Petrels and managed to get teams out to Lizard and Porthgwarra on the same night. PG won out, catching 52 birds, including birds originally ringed in France and on Skokholm Island, Wales (as an adult in 2016). The Lizard team caught 22 birds, but also two birds from elsewhere: birds ringed in 2018 at Portland, Dorset and on Bardsey Island in North Wales.

Aside from that, we've mostly been counting and ringing chicks recently, including Chough, Dipper, Cormorant, gulls and Kittiwakes. It's been fun as well monitoring successive Robin nesting attempts at Penventon Garden Centre, nesting in amongst some of the plant displays! The first fledged two chicks, with two dying in the nest (lack of food due to the baked-hard ground perhaps?), and the second attempt (photographed below) currently has five chicks.

We're also well into the first checks of the Barn Owl season and whilst some pairs are only just hatching chicks now, others already have chicks that are 5-6 weeks old!

One of a brood of five chicks ringed last week on the Lizard

A rather unusual barrel nestbox we found removed from an old site near Marazion.
There must be some pirate heritage in birds that nest is such an impressive barrel.
Whilst most of the owls we've been ringing have been in boxes, it's also been busy in the owl hospital at the Screech Owl Sanctuary. We've already made several visits this year to ring birds before release and our last visit saw us ringing three small chicks (including the very rusty bird below), an older chick and an adult.

Away from ringing, we've now managed to count the gull nests on Mullion and the total of 71 is on par with previous years, though the number of eggs and chicks is second highest we've seen.

2013 2014 2015 2016 2017 2018 2019
GBB Gull nests - 62 37 83 70 60 71
GBB Gull eggs/chicks 98 174 90 204 166 - 195
GBB Gull chicks ringed 4 17 12 13 5 3 -
Cormorant nests 24 52 50 39 47 38 47
Cormorant chicks ringed 11 19 7 16 0 0 14

We've also seen the first Kittiwake eggs of the year, at Rinsey. At the same time some of the Shag chicks are already close to fledging!

The main zawn at Rinsey, sadly now pretty much devoid of Kittiwakes
and with drastically-reduced Shag numbers

Next on the agenda is trying to up our numbers if colour-ringed adult Kittiwakes and then we'll be thinking about gulls and more owls! It never ends...

20 April 2019

Cormorant ringing on Mullion Island

With the swell finally dropping off, this morning gave us the opportunity to get over to Mullion Island to ring some Cormorant chicks. With a ragtag fleet of a kayak, a dingy and a paddleboard we made it over and in pretty perfect conditions. We thought we were pushing it with timing, but remarkably a lot of birds on the island were still on eggs!

But there were enough birds to keep us occupied and in less than 45 minutes we colour-ringed 13 chicks, with one smaller bird just metal-ringed. With birds from the island moving as far south as Spain (see a map of Mullion Cormorant movements here) it'll be fascinating to see where this year's birds go.

In previous years, the ringing totals have varied rather depending on where the birds nest and how accessible they are: 2013 (11 chicks ringed), 2014 (19), 2015 (7), 2016 (16) and none in 2017 or 2018 when the nests were all too close to the edge of the island to access them safely.

1 April 2019

Welsh Cormorant on the boating lake

The good thing about Cormorants is that they're big, so have big rings that with patience can be read on confiding birds. In the last couple of years we've had reports of two birds from Little Saltee Island, Co Wexford: a chick from 2106 seen at Helston Boating Lake in July 2017 and a chick from 2010 seen at Swanpool in December 2018.

The latest though was a bird ringed as a chick on Puffin Island, Anglesey last year that was photographed on Friday at Helston Boating Lake.

Thanks to Terry Thirlaway for the photo and for passing the info on.

24 January 2019

Zilpzalp at Gwennap

In the UK most Chiffchaffs will be summer visitors, spending the winter to the south and west of us, neatly shown by the online ring recoveries map, showing most recoveries in France and Iberia:

But the wintering birds we see here in Cornwall come from points north and east, a fact confirmed today with the capture of a bird at Gwennap Sewage Works that was wearing a ring from the Hiddensee scheme in Germany!

There have been just 12 reports of German-ringed Chiichaffs in the UK so this was a pretty special bird! This was pretty lucky as we only caught three Chiffchaffs, compared to 23 at the previous attempt when it was colder.

22 December 2018

Mullion gull's Spanish holiday

It was a bit of a surprise this week to receive an email asking for details of a sighting of one of our Mullion Island gulls from January 2018, as the finder had misplaced them. Lucky for us this was chased up as the bird had never actually been reported to us and is the first of our birds to be seen in Spain! So many thanks to Antonio Gutierrez for chasing this and to Juan Carlos Andrés for photographing the bird (below) in Ondarroa harbour on the north coast of Spain.

The ring code (L:BJ9) did sound familiar though and this bird had actually been photographed over the summer on a fishing boat in the Helford River back in Cornwall (below). What's interesting to see is just how worn this bird became over just five months.

Local fisherman Darren Thirlaway reports numerous
colour-ringed gulls from his boat on the Helford

This is only the fourth of our birds to be seen abroad: L:BF8 and L:BJ3 have both been seen at Lampaul, Ile de Ouessant, France and L:DC3 has been seen on Ile d'Yeu.

16 November 2018

Cornwall's first colour-ringed Caspian Gull

Recent high tides and stormy weather have dumped large amounts of seaweed along the south coast and large groups of gulls have been making the most of the feeding opportunity. Many of these birds have been roosting on the rocks off Swanpool and Maenporth, giving Greg Wills from the group a chance to check lots of legs for colour rings.

In amongst the throng of birds at Swanpool beach on 13th November, one beast stood out though, with long legs, white head and very long wings; all classic Caspian Gull features. It was also sporting a yellow ring which really was exciting, as there's never been a record of a ringed Caspian Gull in Cornwall.

X609 at Swanpool beach on 13th November 2018 (Greg Wills)

Many thanks to Ronald Klein in Germany who quickly replied to confirm that this was indeed one of his birds, ringed as a chick at Grabendorfer See in eastern Germany. The island colony does hold good numbers of breeding Caspian Gulls, but it's thought that there are also numerous hybrids produced in the colony. The consensus on this bird though is that it's a pure Caspian Gull and not a hybrid. Interestingly, this same bird was also seen at Newhaven, Sussex in September, with the photo below on the Sussex Ornithological Society news page.

X609 in Sussex in September 2018

Also of note in the melee of birds at Maenporth was an old friend not seen for a few years. Red S:037 was ringed as a rehabilitated bird at Secret World in Somerset, being released near Burnham on Sea in July 2011.

Colour-ringed juvenile gulls in the release pens at Secret World

It may well have originated in Cornwall, as it has since been seen at Newlyn (October 2011), Lizard (March 2014) and Swanpool, Falmouth (December 2014). It was actually the first bird from the project to be resighted away from the release site, so nice to still see it doing well!

Red S:037 at Swanpool in December 2014 (Samuel Perfect)
Red S:037 at Maenporth in November 2018 (Greg Wills)

15 November 2018

Welsh Stormies and Falmouth gulls

It's been a while since I've got round to blogging, but then it seems of late we've just been looking at colour-ringed gulls and not much else! But we did receive some interesting reports from BTO recently, involving Storm Petrels recaught at Skokholm Island in south Wales earlier in the year.

The Bird Observatory recaught no fewer than 11 birds ringed by us, including four on just one night (22nd July, when 142 were caught on the island). Of these 11, six had been ringed in 2015 and 2017 at Hot Point, Lizard, with the other six all ringed on 15th July at Gwennap Head, Porthgwarra. This further highlights the link between sites in the English Channel and Irish Sea.

As part of a PhD application for one group member we've also been looking at some of our gull data from Falmouth, so thought we'd share. So across all of our gull sites we've colour-ringed 276 birds, including 199 chicks. Just in Falmouth the figure is 140 birds colour-ringed, of which 85 were chicks. These Falmouth birds have then generated 509 sightings, with 63 of the 140 being seen at least once after ringing. Some of these have only been seen once, but our most reported bird has been seen 60 times now.

Number of resightings of individual birds colour-ringed in Falmouth

Obviously the more sightings we receive the better we understand their behaviours and movements, so if you are a local birder then please keep an eye out for our blue-ringed birds.

14 August 2018

Cornish Barn Owls in 2018

With all of our Barn Owl sites now visited for the year, it's a good time to crunch the numbers and see how they've fared this year. This is our eighth year of monitoring boxes in Cornwall, but we'll just compare 2018 to the last five years for ease:

20132014 2015 2016 2017 2018
Sites visited 32 44 41 47 64 85
Unoccupied 12
Occupied but no breeding 7
Average clutch size
(where observed)
3.64.6 5.2
Average brood size
(where observed)
2.43.5 3.3
Number of chicks ringed 1963 704790 126

The larger number of boxes visited is due to the funding from Paradise Park which has allowed us to really expand the scope of the project. There are several more new sites for 2018 as well which we hope will be occupied in the coming years. The high rate of unoccupied boxes is also due to the large number of new sites that birds have yet to move into.

However, we did see several regular sites unoccupied for the first time which may well be due to the mortality over the hard late winter weather. These two periods of snow cover won't have made it easy for birds to get in condition for breeding and it does seem that some regular sites weren't occupied, but those that did breed made the most of the good spring weather by laying quite big clutches (including a clutch of seven at one site). But we then saw one of the hottest and driest periods on record, which seriously stunted grass growth, and no grass means no voles. So most sites then saw significant brood reductions, though the average of 3.3 chicks still compared well to previous years.

We also think the 'Beast from the East' has had a greater impact on the breeding population than you might think, apparent by the number of birds breeding in their first year. This summer we've caught 15 adults already carrying rings, of which six were ringed as chicks in 2017. Compare this to the totals from the previous few years:

Year Ringed adults
Ringed as chick
previous year
2018  15 6
2017 11 0
2016 9 2
2015 8 2
2014 13 0

We can only assume that these birds (some at regular sites) were new recruits following the death of an 'original' adult, but if this has happened across the whole population then that my lead to quite a drop in the average breeding age. But that's why we do what we do and what the project is all about; understanding these changes in the county's Barn Owls.