19 December 2016

Continental Coal Tit (?) and more Sibe Chiffs

Another calm week gives us the opportunity to get back into our sewage works sites, with this morning seeing us at Gwennap works. The cold weather meant that good numbers of Chiffchaffs were taking advantage of the abundant insects on site, and our 58 birds caught included an impressive 33 Chiffchaffs. Of these, five were 'Siberian' Chiffchaffs (tristis race), some more distinctive than others.

But the highlight was this rather interesting Coal Tit, which we're pretty sure was of the nominate Continental race. Whilst it didn't have the classic peaked-crown appearance, the blue-grey mantle and very extensive bib do seem to point towards this race. We're keen to hear other opinions though...

The five tristis Chiffchaffs also gave us the opportunity to compare the extremes of the race, with two birds being of the classic cold grey appearance, whilst the others showed varying degrees of olive/yellow in the plumage. Below is one of the least obvious examples, but DNA identification of such birds does always comes back as tristis.

14 December 2016

Cormorant coincidence

This afternoon we received a report of one of our Mullion-ringed Cormorants, seen at Chard Reservoir, Somerset in early November. But the bizarre coincidence was that it had been photographed stood next to a second colour-ringed bird, ringed as a chick on Kreupel Island in The Netherlands earlier this year.

Orange TB6 and red BR together at Chard Reservoir
Kreupel Island has a fascinating history, being created as a bird refuge between 2002 an 2004 when 3 million cubic metres of dredged material was dumped on an existing sandbar. It is now home to Europe's largest Common Tern colony.

Many thanks to Kevin Harris for reporting this bird, with the photo above coming from the Chard Reservoir sightings page.

23 November 2016

Return to the sewage works

After a long absence we've finally managed to get back access to our sewage works sites for the winter, which is great news. Last week we had out first session at Gwennap works, ringing 11 Chiffchaffs, including one tristis bird.

This morning we headed to Ponsanooth and although it was a bit quiet (to warm) we did have a good morning with a few interesting birds, so below are a few of the highlights (thanks to Jack Burton for the better pics!).

Although showing a few green and yellow tones, we're sure this is also a tristis Chiffchaff
Green Woodpecker showing off it's sticky tongue
The general plumage and length of the first primary indicated this was an adult female,
but one that had oddly retained just one primary covert, on one wing only
A cunningly-placed net managed to intercept one of the two Green Sandpipers
using one of the settling tanks

We often think of Robins with spots as juveniles, but this bird was ringed in November 2014.
The give-away is the fact that the spots get larger towards the outside of the wing,
rather than towards the ody as in a juvenile bird.

15 November 2016

Late autumn 2016 at Nanjizal - 100 Yellow-broweds and counting

Like many ringing sites in the UK, 2016 didn't seem to be the best of breeding seasons, with the cold, wet spring seeming to have reduced the amount of successful first broods. Compared to 2015, the most noticeable drop in numbers over the autumn was for Sedge Warbler, from over 1,300 ringed to barely 700 this year. This may have been due to the weather and slightly reduced coverage, but the national picture seemed to be show a poor breeding season. Blackcaps were late arriving in September and, like Sedge Warbler, in much lower numbers. The current total of just over 1,450 again compares poorly to the 1,933 ringed in 2015. The only real up sides saw Willow Warbler pretty stable at 469 compared to 473 last year, and Whitethroat actually increased, from 248 to 366.

During September coverage was similar to last year, but increased dramatically in October with extended periods of calm weather. During this later part of the autumn, the most noticeable absentees were the crests. There may yet be more to come, but the total of just 167 Goldcrest is well down on last year's 469. Similarly, just 27 Firecrest ringed so far doesn't compare to the bumper catch of 114 in 2015. The highlight of the autumn though was the mass arrival of Yellow-browed Warblers. After the dramatic increase in 2015 (with 22 ringed), this autumn has so far seen an incredible 105 birds ringed, with 13 ringed in one day alone! Long-distance movements of Yellow-broweds are rare, so we were surprised to catch a bird in 2015 ringed in Lincolnshire the week before. This year, we retrapped a bird on 31st October that had originally been ringed at St Abb's Head, Borders on 9th October, almost 700km to the north.

Other unusual species trapped during the autumn include two Nightingale, four Wryneck, Melodious Warbler, Marsh Warbler, an unprecedented two Paddyfield Warblers, two Dusky Warbler and Little Bunting. With the weather now turning for the worse, it's doubtful we'll get many more days in before packing up at the end of the month, which is a pity as the thrushes have arrived and the ongoing turnover of Chiffchaffs has included numerous tristis, with several 'Siberian' Lesser Whitethroats also turning up, but more on these later...

7 October 2016

Stripe overload with SEVEN Yellow-broweds ringed

It's always a highlight of a day out birding or ringing when you come across a Yellow-browed Warbler, so to find three on our first net round at Nanjizal was an absolute bonus! These stunning little birds originate in the Siberia and used to be rather scarcer than they are now, but with hundreds arriving along the east coast over the last couple of weeks it was only a matter of time before they filtered down to the southwest.

Three happy ringers with a Yellow-browed each
As if that wasn't enough, our second net round also produced three unringed Yellow-broweds, with one later in the morning bringing the total to a staggering seven birds! This brings the autumn total to10 birds, which compares well to previous years: the annual total in Cornwall counting backwards are 24, 13, 19, 8, 3, 4, 1, 7, 6.

The morning ended on 167 birds ringed, including 44 Blackcap, 28 Robin (fresh-in Continental birds), 27 Meadow Pipit, 26 Chiffchaff, two each of Willow and Reed Warbler, Grey Wagtail and Stonechat, a single Firecrest and the mystery bird below... Scroll down for the species.

A very smart first-year female Whinchat!

21 September 2016

Big day at Nanjizal

It's not often the ringing group has a really busy day netting, but this morning was a bit of an exception. A small group of us headed to Nanjizal, with weather conditions looking good and lots of birds around locally. We weren't disappointed, and the first net round alone must have produced 150 birds! OK, so 50 of these were Meadow Pipits from a V of nets we'd set up, but many of the rest were Blackcaps.

Just one net, full of Blackcaps

We ended the busy morning on 248 new birds, including impressive totals of 96 Blackcap, 71 Meadow Pipit, 32 Chiffchaff and five Grasshopper Warbler. Add to that a scattering of common species and singles of Spotted Flycatcher, Firecrest, Grey Wagtail, Garden Warbler and Wryneck. Rather bizarrely, the Wryneck was in the Meadow Pipit nets, sat right out in the middle of a field!

Whilst we were all out an about, we took the chance to visit a few Barn Owl sites to check for  second broods. We didn't find any, but did have one box occupied by a ready-to-fledge Stock Dove. Interestingly, this is actually a much less frequently ringed bird in Cornwall than Wryneck; the last five years have seen seven Wrynecks ringed, but only four Stock Doves!

12 September 2016

A day of colour-ring reads

Since we've started colour-ringing Cormorants and Great Black-backed Gulls on Mullion Island we've also aimed to read rings on these birds locally and yesterday a few ardent colour-ring readers did a sweep of a few local sites.

Cormorant TBT (ringed on Mullion in April 2016) was at Drift Reservoir, whilst Hayle estuary only produced a single St Ives-ringed Herring Gull. Stithians Reservoir fared slightly better, with three of our Herring Gulls seen; one from St Ives and two from Falmouth, including W:001 which was one of the first birds ringed by the project.

W:001 as a chick on the roof of Falmouth Marine School in 2013
Elsewhere, one of our Herring Gulls was seen at Helston Loe Pool, but was flushed before the combination could be read - by the visiting Dalmatian Pelican!

Further along the coast, closer to Mullion Island, a walk along the cliffs at Halzephron (north of Gunwalloe) is sometimes productive, though another of our Cormorants sat offshore was too distant to confirm. We did manage to get close enough to a group of loafing Great Black-backs to find one colour-ringed bird, but it wasn't from Mullion Island.

Yellow 0JJ6 is a bird ringed as a chick off Herm in the Channel Islands in June 2010 and was seen around the islands until spring 2011. This isn't its first trip to Cornwall though, as it was seen on Hayle Estuary October 2011, with only two sightings since; back on Guernsey in September 2012 and then in France in May 2013. So where it's been for the last three years is unknown.

The small roost at Halzephron Cliffs, with Mullion Island in the background

7 September 2016

Perfect timing for a Paddyfield

There are always benefits to being social and this morning I thought I'd just briefly nip down to Nanjizal to say hello to the visiting ringing group who are down for the week and drop off some rings. When they returned from a net round with just half a dozen birds I realised they were having a quiet morning! OK, so they'd just recaught a Dutch-ringed Reed Warbler (the first from there to be found in the county!) and earlier in the week they had ringed Common, Green and Wood Sandpiper, but it was still a bit quiet.

A trio of sandpipers!
 My timing was perfect though as the sixth bird out of the bag was a bit more interesting!

Juvenile Paddyfield Warblers get very worn very quickly, but the smart tertials give away its age

This young Paddyfield Warbler popped up just over two years after we'd caught a much darker one at Nanjizal (see the blog post here), so two at the same site is rather incredible! The first for Cornwall was as recent as 1996, with these two ringed birds being just the fifth and sixth county records.

The 2014 Paddyfield for comparison
If the thought of using more B+ rings then B rings in a week's ringing might tempt other groups to come down for an autumn week, then check out some info on our Nanjizal page.

2 September 2016

Not a bad first morning's netting!

We were joined netting yesterday by a new trainee, working on her PhD with the Cornish Jackdaw Project. Having ringed a heck of a lot of Jackdaws, this was Vic's first session out mist-netting and although we only caught 26 birds we certainly had quality over quantity. So you can't complain when the first non-crow you get to ring is a Stonechat (a scruffy moulting juvenile), closely followed by Tree Pipit, Reed and Sedge Warblers and lastly a Kingfisher!

The rest of the day was spent touring round a few regular haunts for colour-ringed birds, with mixed success. Men-aver beach held our first juvenile Med Gull sighting of the year, ringed in France in July and whilst watching it a Curlew casually walked behind it showing off a combination of red and green rings. It seemed vaguely familiar and was in fact a German-ringed bird first seen in Cornwall on the Roseland peninsula in August 2013 and then at Men-aver beach in August 2014 but not since.

Next stop was Gillan creek, where the only colour-ring on show was one of our own. W:085 was ringed as a chick on the roof of the Marine School in 2015 and not seen since.

Last up was a brief stop-off at Stithians Reservoir, where TBY, ringed on Mullion Island over the summer, was still sat on the island. All before making a brief appearance on BBC Five Live Drive (from 01:56:00) to talk about gull 'attacks' in Scarborough!

29 August 2016

Green 0T0

We've been finding it quite difficult to catch up with any significant numbers of Mediterranean Gulls at our regular sites (Men-aver beach and Gillan Creek), so colour-ring sightings have been few and far between. But yesterday we did catch up with Green 0T0 which is an occasional visitor to Portscatho and the Helford river.

Distance and poor light weren't conducive to a decent photo of 0T0

Ringed as a chick in Vendée, France in 2011 Green 0T0 was first seen in Cornwall in September 2011, then again in October 2012. By December 2012 it was down in Portugal, moving east to Spain in February 2013. It was then back in France before being seen in southern Portugal the next winter. Since then it's only been seen in France, before returning to Cornwall in August 2014 and now August 2016.

This is one of the wider-ranging of the birds we've seen in the county, so hopefully it will continue to wander!

27 August 2016

Chats and pipits

Just two of us ventured out yesterday to make the most of the calm weather at Gunwalloe. As we've not been able to run the CES this year (due to an inaccessible net ride) we could use 'tape' lures to increase our catch of migrant warblers. It worked!

Our catch of 104 birds was excellent, especially considering most of these came from a single 40' net and a net right out in the open at the edge of the new turnip field. The main species were Whitethroat (19), Sedge Warbler (17) and Chiffchaff (10), though the highlights were three Tree Pipits (the first we've ever caught here) and three Stonechats (two juveniles and an adult male).

Other sessions this weekend have seen the group ringing Spotted Flycatcher and a dozen Grasshopper Warblers at Nanjizal and a very smart Whinchat at Marazion.

21 August 2016

2016 Barn Owl numbers

With all the monitoring of first-brood Barn Owls now finished, we can get a good picture of how the season went. The table shows the standard figures we work out every year and it's clear that 2016 was a pretty dismal affair.

2011 2012 2013 2014 2015 2016
Sites visited 32 34 32 44 41 47
Unoccupied 2 (6%) 7 (21%) 12 (38%) 11 (27%) 11 (27%) 12 (26%)
Occupied but no breeding 13 (41%) 2 (6%) 7 (22%) 7 (18%) 7 (12%) 8 (17%)
Average clutch size (where observed) 4.8 4.1 3.6 4.6 4.6 4.6
Average brood size (where observed) 3.1 3.1 2.4 3.5 3.5 2.8
Number of chicks ringed 33 46 19 63 70 47

Whilst the number of sites we monitor has increased (and will increase more with some very generous funding from Paradise Park), and occupancy remained average, productivity was very low. The average clutch size was similar to previous years but brood sizes were lower than the last couple of years. We also saw four complete failures which is still very unusual in the county.

We think this is due to the cold, wet spring weather, which meant that many birds were either not in good enough condition to breed, or did breed but didn't find the food to raise larger broods. We also found that many birds were developing very slowly, so several visits to ring chicks found that they were just too small, so extra visits were needed. This also meant that there were quite a few 'abandoned' chicks brought in to the Screech Owl Sanctuary; not all survived to fuully-grown, but those that did were also ringed by the group before release.

This poor season seems to have been mirrored across the west of the UK and we can only hope that this will improve in future years.

19 August 2016

Injured Peregrines, Portland Stormies and a super-fat Sedge Warbler

We recently received details of some of our ringed birds that had been found elsewhere, both recaptured alive and found dead.

The saddest was the finding of two injured Peregrines, both ringed as chicks in the same nest near Botallack in May. One was found grounded with a broken metacarpal near Helston on 15th August and a second was found the next day near St Just, with a broken humerus and ulna. Both are now receiving veterinary care and we hope they'll recover enough to be released again.

Another interesting set of movements involved three Storm Petrels, all moving between Hot Point, Lizard and Portland Bird Observatory in Dorset (just over 200km). Over the summer we caught two birds originally ringed at Portland Bill (2699028 and 2699030) and have just heard that a bird we ringed on 5th July was recaught there on 19th July. These are the first movements of Stormies between us and Portland, so to have three in a summer is rather coincidental!

Last but not least was a more expected recapture of one of our Reed Warblers on the Isles of Scilly. D791823 was ringed at Marazion Marsh on 8th August 2015 and recaught at Porthellick, St Mary's on 10th June 2016.

Movements of the Peregrines (red), Storm Petrels (blue) and Reed Warbler (green)
On the ringing front, we've been battling the wind and Cornish mizzle to fit in some mist-netting sessions, but have only really managed a couple of Swallow roost catches (totalling 144 birds (and one Sand Martin)) and a couple of mornings in the reedbed, ringing 70 warblers and Reed Buntings. You know migration is well underway though when you catch a Sedge Warbler completely covered in fat. The bird below (excuse the rubbish photo) felt like a tube of butter, being completely covered in stored fat. Considering the fat-free weight of a Sedge Warble can be as little as 9.5g, this bird weighed in at 19.8g!

6 August 2016

Not often you get four controls in one net

Last night our numbers were swollen by visitors from up-country, allowing us to us divide our time between nocturnal netting sites on the Lizard. First stop was Gunwalloe where we netted the Swallow roost for the first time, starting off well catching a decent number of warblers and a couple of Reed Buntings (very much lacking in recent years). Numbers of Swallows soon increased, but the roost was rather disrupted by a pack of Starlings also choosing to roost close to the nets, of which we caught a small number. But once these were cleared, Swallows dropped back in and we ended the night with 50 Swallows (along with nine Reed and eight Sedge Warblers).

With most of the team staying to process Swallows, two decamped to Hot Point, Lizard to set nets for Storm Petrels. In amongst a very eerie sea fret, we netted through to 3am, catching 60 birds. The highlight though was one net round which produced five ringed birds (in the same net)! These included birds from Portland Bill (Dorset), Dingle peninsula (Co Kerry), a recapture of a bird we ringed in July 2015 and incredibly two birds carrying rings from the Channel Islands Ringing Scheme.

These birds will almost certainly have been ringed on the small island of Burhou, but we'll have to wait for confirmation. This is rather exceptional though, as to the end of 2015 only 12 Channel Islands ringed Storm Petrels had been recaptured in Britain & Ireland (four of which have unsurprisingly been in Cornwall).

Just for a brief distraction we also caught a bat, which we think was a Pipistrelle... ***UPDATE*** It was apparently a Whiskered Bat!

24 July 2016

Trewavas Kittiwakes 2016

You might have seen a few posts from us over the summer with various photos of Kittiwakes at our study site at Trewavas/Rinsey, but yesterday saw effectively our last trip to the colony. With many failed breeders now departed and numerous chicks fledged, the colony has become rather quiet, or in the case of Rinsey deserted!

So what better time to offer a brief summary of the year. On the good side, the two sites at Trewavas Head fared pretty well, holding over 120 pairs of birds. This compares to around 70 in previous years so was a welcome increase. Some of these birds may have relocated from Rinsey though, where numbers were again very low (more on that later). Records of colour-ringed birds give us a little bit of insight into these movements and this year we saw six birds at Trewavas that had been recorded previously at Rinsey. Two of these were actually ringed as chicks in France (in 2007 and 2008), giving yet more insight into how these birds move around.

Part of the colony at Trewavas Head

Other French-ringed birds at Trewavas included birds ringed as chicks in 2002 and 2005. We also recorded 16 birds ringed at Trewavas in previous years, including a bird also photographed at sea in 2014 (see pics here), and also a bird originally ringed on the Isles of Scilly in 1996, caught and colour-ringed here in 2015.

At Rinsey, the only colour-ringed birds seen were a French bird ringed as a chick in 2005 and seen quite regularly and a lone bird ringed by us in 2013, which visited just once in February 2016. Breeding at Rinsey was also a write-off, with just nine pairs attempting to nest but all failing before the end of the season.

So a season of good and bad across the sites, but with some interesting stories building...

4 July 2016

Full day of seabirds (and some cannibalism)

You know it's seabird time of year when you're heading out ringing for the day and your roof rack looks like this! Add to that a back seat full of paddles, buoyancy aids, drybag, VHF radio and an assortment of rings and colour rings and we were in for a long day...

First port of call was to take two boats over to Mullion Island to try to track down some of the 203 Great Black-backed Gull chicks/eggs we'd counted earlier in the year. Very few birds make it to a ringable size though, but with a record count this year hopes were high. The vegetation was, as ever, challenging and wading through the mallow and sea kale looking for chicks is a laborious job.

Even large chicks are remarkably good at hiding in low vegetation
True to form we found very few birds, which is always a bit depressing; a full sweep of the island found just 13 birds! These were all a good size to ring and colour ring, so it'll be interesting to see where these birds go wandering.

Some birds aren't quite so good at hide-and-seek though

Part of the reason so few birds survive to this stage was evident all around the island though, with at least 16 relatively freshly-dead chicks found. Some of these were pretty well-grown so it does look like predation (or more accurately cannibalism) remains a driver of the low productivity on the island. We're not sure how commonplace this is, but it doesn't seem to be the best strategy for a colonial-nesting bird!

Once we were back over from Mullion, we headed straight round to Praa Sands for the long paddle round to Trewavas Head to the second of our Kittiwake sites (only accessible by kayak). Unfortunately, the swell was way higher than forecast, so it wasn't safe to land and in any case the tide was really high which would have made accessing nest sites rather treacherous! This isn't the easiest of jobs at the best of times, as kayaking round the headlands with a double-ladder strapped to the side of your kayak is tiring to say the least. Makes landing interesting as well and I must admit we did get barrelled by a wave coming back in to Praa Sands.

Last job of the day (after an impromptu ringing group BBQ in the evening sun) was to make the most of a calm, new moon night to get nets up for Storm Petrels. The first net round before midnight produced over 25 birds so we knew we were in for a busy night, but sadly the Cornish mizzle came in at 1am and we had to beat a hasty retreat before the rocks got too slippy. But although we'd not made it to the busiest time of the night the total of 55 new birds was pretty good. It was a bit surprising to find these were all new birds, so we'll just have to go out again on Tuesday night and hope to recatch some ringed birds...