17 September 2021

Barn Owl 2021 update

Yesterday afternoon we ringed our last (and latest ever) Barn Owl chicks for 2021, with two present in a box near Carnkie. This was a replacement brood after an earlier failure and only the second time we've ringed chicks in September.

The last Barn Owl chicks of 2021 - a pale male (left) and a darker female

This is then the ideal time to have a look at the numbers and see how 2021 was for our owls. It was an unusual year, with some early broods, some late broods, some regular sites unoccupied, some new sites occupied and generally just lots of surprises.

The totals for the year are below, showing slightly fewer boxes monitored this year, which we can partly blame on lockdown again, so we hope that 2022 will see us back up to checking over 100 boxes. The average clutch size was the lowest we've seen since 2013 which may be a consequence of the spring weather. This also followed through to smaller brood sizes, which were also much lower than in recent years, and fewer chicks ringed than last year.

2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021
Sites visited 32 34 32 44 41 47 64 85 87 106 93
Unoccupied 2 7 12 11 11 12 23 34 36 43 35
Occupied but no breeding 13 2 7 7 7 8 5 4 3 4 5
Average clutch size
(where observed)
4.8 4.1 3.6 4.6 4.6 4.6 5.3 5.2 4.7 4.6 4.5
Average brood size
(where observed)
3.1 3.1 2.4 3.5 3.5 2.8 3.0 3.3 3.0 3.2 2.8
Number of chicks ringed 33 46 20
63 70 47 90 132 119 177 130

We always see a few short movements during the year, with ringed chicks taking up residence in boxes, so below is a map of these noted in 2021.


A few of these are quite interesting though. One site near Zennor was obviously very lucky, with chicks from 2016 (with consecutive ring numbers) both found breeding in other boxes in Penwith in 2021. One had bred at a different site in 2019, but then moved on again in 2021, whilst the other was a new breeder five years after ringing. We also had an adult female switch boxes, having bred at a site for at least two years. she moved a few kilometres down the road to a new site to breed.

One other unusual, and sad, story involved a bird found breeding in a box in June 2020 (with three chicks) that was already ringed. Unusually the ring showed it was of captive origin and had actually come from a breeder in Torquay before ending up at the Screech Owl Sanctuary near Bodmin. It had escaped from there during a flying display and obviously found the wild to its liking, breeding nearby. It then bred again in 2021 but in a different box, but was the sadly found injured six weeks later and was taken back to the sanctuary. The local vet found that it was too injured to be rehabilitated so was sadly put to sleep. It's great to know the full-circle history of this bird, despite the sad ending.

10 September 2021

Returning Osprey

We've previously blogged about a Scottish-ringed Osprey seen at Devoran on its first autumn migration and then again three years later, so read the background here. Remarkably, Blue JF1 has returned again, seen at Restronguet Creek yesterday. We're not sure if it was seen back in Scotland since rigning, but it's great to know that it finds Devoran to its liking and on past performance it will remain on the river for a while yet.

Thanks to John St Ledger for the report and the classic Osprey photo.

2 September 2021

Autumn colour-ringed waders (and a tern)

Autumn migration generally sees us receiving a few colour-ring resightings of migrants, especially waders , but this year has got off to a great start! Just over the last week we've heard of some really quick movements of birds leaving the country via Cornwall.

First up was this Ringed Plover seen on Looe Island on 24th August (photographed by Jasmina Goodair). Incredibly it had only been ringed two days earlier in North Wales, so had made a very rapid departure. It's also the first Welsh-ringed Ringed Plover to be found in Cornwall which makes it extra special.

The plover was closely followed by this Dunlin, seen at Colliford Reservoir on 30th August (photographed by Linda Birtwistle). This too was a Welsh bird, having been ringed on 12th August at Ynyslas NNR, near Aberystwyth. This is now the third colour-ringed bird from this project seen here.

On a slightly different Celtic note, this Sandwich Tern was photographed (by Adrian Langdon) with a flock of Mediterranean Gulls on the Camel estuary on 28th August. It had been ringed as a chick at Lady's Island, Co Wexford in June 2019. Since then though it has been seen on the Isles of Scilly (September 2019) and also in Namibia (March 2020).

Gulls resting on oyster floats off Porthilly, Camel estuary

So do keep an eye out for any colour-ringed birds and feel free to drop us an email if you don't know where to look to find out where it's from.

16 August 2021

Manxies, some very late owls and a Norwegian Curlew

We've been busy over the last couple of weeks, so have a few bits of news to share.

Over the August new moon we ran two Storm Petrel public ringing demonstrations, aiming to give people the rare chance to see these amazing birds up close. The visitors to Porthgwarra were not only treated to seeing a few Stormies in the hand (and enjoying their distinctive smell), but also a couple of Manx Shearwaters! These are only the second and third we've caught in Cornwall so it was incredibly lucky to have two on the same night. As far as we can tell, only 28 Manxies have ever been caught in the county, including seven in 2002, one by the ringing group at Lizard in 2015 and now two more.

Over the weekend we also took the opportunity to visit the last two active Barn Owl sites we monitor. both of which we think are replacement clutches after an early failure. Sadly one of these didn't progress past two eggs, but the other had a brood of very young chicks (and possibly two unhatched eggs), so these are likely to be ready to ring in September. We rarely ring chicks this late in the season and in fact we've only ever ringed one brood in September, on the very late date of 22nd September 2020.

Lastly, we were contacted this morning by the Head Greenkeeper at Newquay Golf Club as one of their staff had found a dead Curlew on the course, sadly predated. The bird was ringed though and is in fact the first ever Norwegian-ringed Curlew to be found in Cornwall. We've had birds from Sweden and Finland in the past, but this bird completes the Scandinavian trio, so it'll be interesting to see where and when it was ringed.

26 July 2021

Four nights, four Stormies to Alderney

Over the years we've shared a few Storm Petrels with the Channel Islands and in total 19 Cornish-ringed birds have been recaught there and seven ringed on the islands have been recaught in Cornwall. In fact, just 56 BTO-ringed birds have ever been found on the Channel Islands, so Cornwall provides a fair proportion of these.

This week we received a rush of reports from Burhou, Alderney though, with four of our birds recaught there on consecutive days:

  • 15th July - bird originally ringed at Porthgwarra in June 2021
  • 16th July - bird ringed at Lizard in July 2012
  • 17th July - bird ringed at Lizard in June 2016
  • 18th July - bird ringed at Lizard in June 2019

Whilst some of these may be wandering non-breeding birds, it's interesting to see birds from 2012 and 2016 which are now breeding age birds. Presumably these are nesting on Burhou, which is in fact the only site that Storm Petrels breed on the islands.

20 July 2021

Back in the marsh

So with a change of tenancy and Covid rules relaxed enough to allow more ringing freedom, three of us ventured into Gunwalloe reedbed for the first non-roost ringing at the site since September 2016. Since that time we've ringed the Swallow roost just twice (in August 2018 and September 2019), so it was great to get back in for some warbler ringing. The site was originally run as a CES (Constant Effort Site) so we hope to restart that in the future.

But as is always the way it has taken a bit of clearance and work to get the reedbed net ride back to a usable condition, including finding the original boardwalk and filling in some gaps. We did still manage to find some poles and guys from years gone by though!

We started early this morning to avoid the heat and with just a small number of nets caught 41 birds before closing up at 9am. Having not ringed at the site for so long it wasn't too surprising to find no local retraps, but we WERE surprised to find two ringed warblers (a Sedge and a Reed), both with AXL rings. The ring sequence did seem familiar and it turns out these were both birds ringed last autumn at Nanjizal (just 30km as the warbler flies), so nice to share some Cornish birds between a breeding site and a migration site.

One of the AXL birds from Nanjizal
Not surprisingly the majority of captures were Sedge and Reed Warblers, but we did also manage a few juvenile Whitethroats and a juvenile Cetti's Warbler. We hope to ring the site more over the autumn so will add updates when we can.

13 July 2021

Busy seabird weekend

This long weekend has been a busy one, with various group members (and even a visitor from up-country) heading out to all parts of West Cornwall in search of (mostly) seabirds.

We started off with our annual gull-ringing trip over to Mullion Island, which was always going to be an unknown as we were too busy colour-ringing Cormorant chicks on our last visit to count the Great Black-backed Gull nests. We headed over in two kayaks and a dinghy, landing in a quiet cove and heading onto the top of the island. Working our way round we ringed just 10 chicks, but at least another 10 were too big to try to catch. Whilst there, we were also able to photgraph a couple of ringed adults, both of which had been ringed as chicks in 2016 but are now breeding on the island. Interestingly, one (L:CN5) had been ringed as a chick on Looe Island, but has been seen a few times around Lizard and Coverack since.

Next stop was a tour of Barn Owl sites around the Lizard, ringing chicks at 10 sites in total. Several of these later broods had just two chicks, in contrast to those earlier in the season that had three or even four chicks.

Back on the seabird theme, the next day found us Kittiwake ringing at Trewavas Head. Half of the team paddled round from Porthleven while the other half walked in with a ladder from Rinsey. We all reconvened at the cliffs to scramble down and kayak round to the main Kittiwake site. With very few birds successfully breeding, we only colour-ringed eight chicks, but at least this is better than the zero of the last two years. We also took the opportunity to read various colour rings at Trequean zawn and also managed to get photographs of two metal-ringed birds. One of these (ET44236) was ringed on the Isles of Scilly in 1999 and had been seen by us at the engine houses colony in 2018 as well, so is a healthy 22 years old now. The other rewmains a mystery at the moment, with the BTO team looking at the possible options for us of what might be a very old bird!

After an extra couple of owl boxes, we then headed down to Porthgwarra for dusk to set nets for Storm Petrels. This is often the busiest month for Stormies and true to form the first net round before midnight saw 45 birds in the nets, so it was a busy session for everyone. In total we ringed 95 birds, with recaptures of a French-ringed bird and others ringed on the Calf of Man (in August 2020), St David's, Pembrokeshire (in July 2020) and one of our own from Lizard (ringed in July 2020). Talking of Stormies, we also heard from the BTO that a bird we ringed at Lizard in August 2020 was recaught on Alderney, Channel Islands on 10th July.

So al in all a very productiove weekend of seabird ringing, contributing to our ongoing colour-ringing projects for some of these species.

4 July 2021

A mediocre Kittiwake season

At the weekend we had an evening paddle out to the Kittiwake colony at Trewavas Head to continue our Retrapping (or resighting in our case) Adults for Survival project. It was the perfcet sea conditions for a kayak, and two of us managed to cover most of the colony in under three hours.

Sadly, as in the past two years, the main site was earily quiet with a lot of birds sat by empty nests or just loafing. Just five nests had chicks, with just four other sitting adults, which is a shadow of the 70 pairs of just a few years ago. We did manage to reread colour rings on 10 birds, all ringed as adults at the same site in 2013, 2015 (2 birds), 2016 (2 birds) and 2018 (4 birds). We also took the opportunity to ring a couple more adults to contribute to the project.

There was slightly better news at Trequean Zawn, where there were at least six nests with chicks and 10 adults sitting tight. Part of this site can only be seen from the sea, so there are no doubt more nesting birds than this. There were more colour-ringed birds here, many with much more interesting histories. Most of these were ringed as chicks, obviously recruiting to a new site away from their natal site. Birds were recorded that had been ringed as chicks at the main colony in 2015 (3 birds), 2016 (3 birds) and 2018 (3 birds), and there was also a chick ringed at the engine houses area of the cliffs in 2017. Interestingly there were also four adults at Trequean that had been ringed as adults at the main site in 2016 and 2017, and still recorded there in 2020.

PP was ringed as a chick in 2015 and has successfully
bred the last three years at Trequean
 Additional to these local birds were three French-ringed birds, ringed as chicks in 2007, 2011 and 2015. These also have interesting histories, with one of them seen previously at Rinsey in 2018, 2019 and 2020, and another (OWM-RNN) that was at the main Trewavas site in 2012-19 before moving to Western Cove, Portreath in 2020.

It'll be interesting to see how the birds get on at the main site and whether or not more move along to Trequean in the future.

3 May 2021

More Mullion Cormorants

We've never had the chance to make two Cormorat ringing trips over to Mullion Island, but the spacing of the colony this summer allowed us to get over safely again at the weekend. Thanks again to Lizard Adventure we took a few kayaks over and landed both side of the island so that we could corral the young birds in the Sea Mallow.

Some of the larger birds we let waddle off onto the top of the island so we could concentrate on the medium-sized chicks. With an efficient team, we were able to ring 25 chicks, 23 of which we also gave a coded orange ring which can be read at distance. We strictly limit our time on the island (to no more than an hour), so had to leave another dozen chicks unringed. But with a record number of nests this year (at least 73) this was always going to be a productive year. We sadly also didn't have time to count the Great Black-backed Gull nests on the island either, but with plenty of birds sat on eggs (and even a left-over Manx Shearwater meal) we hope they too will have a good year.

Across the two visits we colour-ringed 44 chicks this year which is by far the most we've ever ringed, so it'll be fascinating to see how these birds get on and where they end up. Thanks again to Lizard Adventure for the loan of their kayaks (and guide) and wehope to be working with them again soon when it's time to ring gull chicks.

17 April 2021

Trewavas Kittiwake in Wales

We were recently contacted by Josie Hewitt, who's spending the summer monitoring seabirds on Skomer Island in south Wales. As part of their regular monitoring, Josie photographed a colour-ringed Kittiwake in the week which wasn't local, so got in touch as she thought it might be one of our Cornish birds.

It turns out that Black N5 was indeed one of our Trewavas Head birds, ringed as an adult in June 2018 and interestingly not seen since. In our experience, adults present in the colony early in the season are often wanderers, but the fact this bird was ringed in June (as a breeding bird) is a bit confusing! But considering the main Trewavas colony has failed in the last two years, maybe this adult has moved on, so it'll be interesting to see if it remains over the summer.

This also isn't as unprecedented as it might seem, as our other monitored colony at Portreath has a regular breeding bird that was ringed as a breeding season adult in the breeding season north Wales!

8 April 2021

First Mullion Island trip of 2021

With the easing of restrictions coming at the perfect time, we took the chance of some flat clam seas this morning to make our first trip over to Mullion Island as part of our annual seabird monitoring. Earlier in the season we'd photographed the island from the clifftop and estimated 63 occupied nests, which is the most we've seen on the island since we started monitoring nests in 2013.

With enough big chicks to make a ringing trip worthwhile, with the help of Lizard Adventure we kayaked over and realised that we'd underestimated the number of nests, with the colony spreading deep into the Mallow, hence not visible from the mainland. We need to review the revised estimate, but at over 70 nests this is quite significant.

With three small ringing teams, we managed to ring 21 chicks, with 20 also large enough to take an orange colour ring to allow us to better track movements.

Many thanks to the ringing team and we were on and off the island in under 45 minutes, so minimising disturbance as much as possible. It'll be fascinating to see how this cohort of chicks fare and there may be more to ring yet as many nests still had unhatched eggs!

28 January 2021

Celtic connection

Lots of Cornwall's seabirds are very connected to our Celtic neighbours, with our gulls, Kittiwakes and Storm Petrels regularly commuting across the Celtic Sea and English Channel. We share a lot of colour-ringed Kittiwakes with the two important breeding sites at Pointe du Raz and Pointe du Van on the Brittany peninsula (a few French birds shown below) and several of our supposedly-urban gulls have been seen on French estuaries and ports.

We had news from BTO British Trust for Ornithology this morning that two of our Storm Petrels ringed in July 2020 at Gwennap Head, Porthgwarra were recaught at Banneg in the Molène archipelago the next night. Banneq is the largest Storm Petrel colony in France, with as many as 1,000 breeding pairs. At 187km, this is probably only a short trip for a Stormie, but it still always amazes me what these tiny birds get up to!

2 January 2021

New Year, old Chiffs

It seems to be New Year tradition now that the Cornish weather turns cold enough and calm enough to warrant a visit to the local sewage works. Today was no exception and thankfully the hail showers stayed away long enough to allow a couple of hours mist-netting at Gwennap Sewage Works. There were a LOT of Chiffchaffs around, picking insects off the tanks and from the bushes and small trees surrounding them. My estimate of 80 birds was probably rather conservative.

It only took two nets around a settling tank to keep me pretty busy, catching 81 birds! Of these, an impressive 56 were Chiffchaffs, including seven ringed in previous winters. Four had been ringed on 1st January 2020, with others ringed on 19th January 2020, 4th January 2019 and 5th January 2017. The latter bird (HHB667) was caught again in December 2017 but not since, so in its fourth winter at the site is remarkably site faithful. The national longevity record for Chiffchaff is only 7 years 7 months, so HHB667 is quite exceptional for a wintering bird.

In amongst the 'nornal' Chiffchaffs were several paler, eastern Siberian Chiffchaffs (tristis race) and I was lucky enough to catch four, including an exceptionally pale frosty bird. These eastern visitors normally make up 10% of our wintering birds, so the four caught is about the norm.

Some of the 'bycatch' was interesting as well, including Firecrest, three Grey Wagtails, Pied Wagtail, three Bullfinch and Meadow Pipit. With the weather set to stay cold and calm next week, we'll hopefully have more to report soon.

21 November 2020

Cornwall is a colourful place (for rings)

Over the years various members of the group and local birders have reported a wide variety of colour-ringed birds in the county. As we run a long-term urban gull project, not surprisingly our most-reported species is Herring Gull, but what about other species? A quick look at the numbers from the BTO's DemOn (Demography Online) database gives us records of over 4,500 colour ring reads of 26 different species, summarised by year here:

As expected, other gull species feature right at the top, followed by species that we run RAS (Retrapping Adults for Survival) projects on: Kittiwake, Jackdaw and House Sparrow. We don't ring any smaller gulls ourselves, so all of the records of Mediterranean and Black-headed Gull resightings come from other schemes, often abroad. In fact a lot of the larger gulls are from abroad as well, with French Great Black-backed Gulls topping the table, closely followed by Belgian and French Mediterranean Gulls.

Polish-ringed Black-headed Gull at Swanpool, Falmouth (Mark Grantham)

French-ringed Great Black-backed Gull at Southerly Point, Lizard (Terry Thirlaway)

Belgian-ringed Mediterranean Gull at Coverack (Mark Grantham)

Irish-ringed Lesser Black-backed Gull on Copperhouse Creek, Hayle estuary (Mark Grantham)

Lower down the list are some more unusual species, details of which we've blogged about before, including:

Some of the other more unusual resightings include these smart birds:

Green A61 was seen at Lizard Lighthouse in March 2018 before being seen back on
Skokholm Island where it was ringed just nine days later (Terry Thirlaway)

This Dutch-ringed Sanderling was a regular on Marazion beach in winter 2016-17
and also once in January 2018, but was also regularly seen on
autumn passage in The Netherlands (Ben Porter)

This Dutch-ringed Sandwich Tern at Sennen Cove had been seen
three weeks previously in Tyne and Wear (Clive Richards)

We're always keen to receive new sightings though and can help in tracing birds with the different coordinators, so if you're lucky enough to see any colour-ringed birds then drop us an email with details - westcornwallringinggroup@gmail.com

3 October 2020

Ageing gulls

I don't mean ageing as in the dark art of knowing if that dappled Herring Gull is a third or fourth calendar year bird, but more some of the interesting changes in plumage and bare parts we see as our colour-ringed Herring Gulls grow up.

W:245 was ringed as a chick on the University of Exeter campus in July 2018 and has been seen just seven times at various sites local to Falmouth since. It's interesting to look at how its bill colour has changed this year though, seen in the montage below.

It's also interesting to see how moult progresses through the year as birds rapidly change appearance. W:178 was also a chick ringed in 2018, this time in the middle of Falmouth town, and has been seen eight times since. Both photos below show W:178 at Stithians Lake, in June and September, but note how quickly it has grown through new flight feathers (with 'mirrors' on the tips) and also adult-type wing coverts.

W:178 on 29th June

W:178 on 25th September

Some birds really do change appearance in a matter of months as well. W:249 was also a 2018 campus chick and has been seen eight times in the local area. Below are a few photos of W:249 just from this year and the change is striking, although photos can be deceiving as the bird looks to have taken a step backwards in its moult in September!