Saturday 28 August 2021

Seawatching highs... and lows

After the Lapwing twitch, I headed to the sea to cleanse my soul with several hours of seawatching. The seawatching obs was busy at Flamborough Head and I learnt that I had missed a Euro Storm Petrel; nevermind, plenty of time yet! 

Sooty Shearwaters were moving north, with a few Manx thrown in. Bonxies were heading south, plus several Arctic Skuas and my first Red-throated Divers of the autumn. A stonking full-summer Grey Plover went north. Late morning, Jon Beaumont picked up a juvenile Long-tailed Skua moving slowly north, exhibiting a slim, tern-like jizz and flight, with several stalls before heading north. Subtle, but distinctive. At long-range, not much plumage was visible apart from a pale smudge on the belly. 

After this, passage eased and by midday I decided to have a change of scenery. The Old Fall loop was rather quiet, though two Pied Flycatchers were nice. The highlight was a distant flock of 18 geese which looked like Brents but were too far to clinch. Fortunately, zooming in on the DSLR revealed they were in fact Brents and pale-bellied too. Remarkably, this flock of 18 were seen the day before by my mates Dunc, Mark and Ben (Team Birdo) who were having a mega seawatch at Sheringham, Norfolk (where they also found a Black-browed Albatross!). The flock was then tracked up the coast. 

Next up was a nap, as my 5am start had finally caught up with me. I fell asleep behind Old Fall hedge, listening to a Willow Warbler hoo-eeting in the scrub.


Back to the cliff for the afternoon, I spent the first hour or so phonescoping Sooty Shearwaters and Bonxies practising for when the Pterodroma eventually flies past. Some of the results were reasonable, though at long range and high zoom, the panning is still a bit clunky. 


Just after 2pm a pair of skuas came north at mid-distance. They looked small, with wavering flight and none of the falcon-esque purposeful athleticism of Arctic Skuas. My hunch was Long-tailed and confirmation from Flamborough regulars later was a relief. All four Long-tailed Skuas I have seen in the last week or so have gone north, whereas the majority of Bonxies and Arctic Skuas have gone south. This suggests the LTS have been pushed in from the north and want to reorientate themselves, whereas their larger cousins are happy following the coast and possibly heading overland from the Wash to the Severn.

A push of Sooties and Manxies mid-afternoon raised optimism that something even better would come past; my spidy sense was tingling...... but it was not to be and I headed home for tea just after 4. 


Two Long-tails. Compare with the Arctic Skua below.

Arriving home, I received news that a Fea's-type petrel had gone past Cowbar late afternoon and was then tracked up the northeast coast. Bugger! Did this go past Flamborough while I was there? Was I too busy faffing about, filming stuff?  If these birds are being pushed into the North Sea from the shelf edge to the north of the UK, then perhaps it hadn't got as far south as Flamborough before reorientating, so maybe I didn't miss it. I guess I will never know but this was pretty gripping. And then a Sabine's Gull flew past the fog station at 6pm. Doh!


Pre-match Nerves

 Heading for Headingley to watch the second day of a thrilling cricket match between England and India, news broke of a White-tailed (Plover) Lapwing at Blacktoft Sands. This is the first record of this leggy eastern wader for Yorkshire and only the seventh or eighth for Britain, so a very rare bird. Would it stay until tomorrow? I tried not to think about it too much and enjoy the test match with my Dad and sister. It was a thrilling match and seeing Joe Root score a century in front of his home crowd was fantastic; Joe seemed to enjoy is as much as the crowd! The bird was present until dusk, so I went to bed with a feeling of optimism and an alarm set for 5am.

   Townend Lagoon, early morning. WTL under blue star.

After a short drive to Blacktoft, I arrived on site not long after 6am with only a handful of birders present and no news to lift or destroy my spirits. Thankfully, the bird was still present on Townend Lagoon and at times the closest bird to the hide! I enjoyed superb views with the 15 or so birders in the hide including Marc Hughes, Tom Broxup and other familiar faces. The lagoon was teeming with waders, with Spotted Redshank, c25 Black-tailed Godwits, 48 Snipe, Green Sandpiper, etc and a couple of smart Bearded Tits were feeding at the base of nearby reeds. After watching the superb Lapwing for a while, the lure of seawatching at Flamborough was too strong, so I gave up my space to arriving birders and headed east.



Molly or Albert!

Thanks to Henning (member of Birdforum) my slightly dodgy hypothesis has been corrected, so unfortunately no conclusions can be drawn from measuring the bill in this way as the average values are so close. I am sure Henning won't mind me quoting him here:

"You're working from the implied assumption that bill length and upper bill depth are proportionally connected, which the original table didn't cover. Additionally, the probabilities implied by the standard deviation values for the individual measurements go out of the window as soon as you apply them to the ratio of two values.

Assuming length and depth of the beak as independent, you could estimate that roughly 50% of the males have beak length-to-depth ratios between 4.17 and 3.78, and roughly 50% of the female ones between 4.35 and 3.78.

That's almost perfect overlap in the region where you measured values seem to have been, so I'm afraid it's not possible to draw any conclusions at all from this."


Maths was never my strong point, but it was worth a try!

Therefore, I am still none the wiser as to the Bempton Albatross' gender.

Thursday 26 August 2021

Molly, not Albert?

It intrigues me as to whether the long-staying Black-browed Albatross at Bempton is a male or female. Without capturing the bird or retrieving a feather for DNA analysis it is unlikely this could ever be proved, but I was interested to see if the high-quality photos that some birders have taken could provide a clue. 

Thanks to some guys on Birdforum, I managed to get hold of the key morphological measurements from this paper. Most of the measurements would not be helpful without capturing the bird, but I was interested in the bill measurements to see if based on a sample of good quality pics, I could analyse the bill to see if that indicated the bird’s sex. 


Based on the data in the paper, using the mean bill length divided by mean upper bill depth, you get a figure of 3.96 for males and 4.05 for females. Anything less than 3.96 would be more likely to be male and anything over 4.05 would be more likely to be a female. This should apply to photographs too, no matter what the size as long as the photo was sharp enough to measure accurately and the angle of the bill was as side-on to the photographer as possible.

Having trawled the internet for good quality side-on photos, I found and measured the bill length and upper bill depth in 13 shots that matched the criteria I was looking for. Compared to the mean ratio, I found that five of the pics indicated the bird to be male (measurement ratio of 3.96 or less) and four indicated the bird to be female (measurement ratio of 4.05 or above), with the others were midway between the two.

In conclusion, I think the bird may be female. My reason for that is that providing the bill is horizontal (the process on the underside of the lower mandible is visible) then the only variation will be in length as the bird may be slightly facing away or slightly facing towards the photographer; that would shorten the bill length artificially, meaning that the ratio would favour the male ratio, as you are dividing a smaller number than is real, with a more accurate bill depth, which would lower the ratio. There would be no circumstances in which an inaccurate measurement would favour a female ratio providing the bill is horizontal. Therefore, the fact that four of the measurements look to be equivalent to, or higher than the mean female ratio leads to the conclusion that the bird is more likely to be a female.

I appreciate this is ‘back of the fag packet’ stuff, but thought it would be worth a try! The bird is quite subordinate to the Gannets, hasn’t constructed a nest and does not indulge in much display, although I noted a bit of half-hearted display in the early part of its stay at Bempton. I know nothing of the breeding ecology of this species, but could this behaviour also be significant? 

Whether this albatross is male or female it is still a fantastic bird and it has been a real privilege to see this bird so close to home. 

Excerpt from Ferrer et al. Morphological measurements of Black-browed Albatrosses.

Many thanks to the photographers who's photos I measured.


Wednesday 25 August 2021

Local Wader Passage

One of the biggest frustrations of the York birding scene is the lack of good autumn wader habitat. Besides the well-known pool at Wheldrake Ings and Bank Island, the area doesn't have a lot to offer at this time of year in terms of wetland habitat. Over the years there have been instances of new bits of habitat being created, sometimes accidentally, which have attracted lots of waders, demonstrating how new habitat can pull in birds quickly. This year, two areas have developed which are acting as magnets to migrating waders. 

Poppleton Park and Ride Flood

The first is a flooded corner of a field near Poppleton Park and Ride. It is easily accessible, by heading down Northfield Lane from the Poppleton junction of the A59, by Dobbies/Park and Ride/Vaccination Centre. You can park along the lane opposite the flood. The flooding has been there most of the year and is due to a drainage problem associated with the Park and Ride. Hopefully, the farmer will see the value of this little corner of a large field and maintain it. New wetlands tend to be stuffed with invertebrates which is probably what is holding the birds.

Flood is where the blue star is. 

This site pulled in some waders during spring, including Little Ringed and Ringed Plovers. So far this autumn the site has had Ruffs, Dunlins, Green Sandpipers, Greenshanks, Avocets, Little Stint and Curlew Sandpiper etc, the latter three of which are pretty scarce in the York area. 

Juvenile Curlew Sandpiper (top two) with juvenile Little Stint (bottom two). Poppleton, 25/8/21


Acaster Airfield Flash

The second site has been there a while, but is beginning to develop. Caused by mining subsidence, this is also a flash in an arable field but looks likely to be there more permanently as the cause may be impossible to rectify. Access here is tricky as to view it is on private land, but providing birders are sensible, especially with regards parking, the farmer seems amenable.  

The site is accessed by parking in a gateway at the head of the public footpath - see yellow star. Please take care not to block the gate. Follow the footpath and then take a right down an old runway to the base of the blue arrow, where you can look over the flash. You can walk down the side of the flash (many dogwalkers do) but you risk flushing birds. The central strip is good for Stonechats in winter. Recently, the flash has held Ringed Plovers, Greenshank, Redshank, Ruff, Wood Sandpiper, Green Sandpiper, Snipe, among other waders. The wider airfield is a cracking spot for farmland birds such as Grey Partridge, Barn Owl and Corn Bunting along with migrants such as Ring Ouzels, Redstarts, Wheatears etc on passage, and has held local rarities such as Montagu's Harrier and Great Grey Shrike in the past.

Wood and Green Sandpipers plus Ringed Plovers.


Clearly, with such little wetland habitat along the Ouse Valley near York, any little flood or puddle can pull in birds with new birds turning up daily. Hopefully one of these cracking little spots will pull in a genuine rarity before the autumn is out.

Sunday 22 August 2021

Two mornings at Flamborough

My first chance to get to Flamborough for a while and the conditions looked interesting, with murky skies and some east in the wind. Saturday morning yielded a productive seawatch, with a close Balearic Shearwater, lingering juvenile Long-tailed Skua and Black Tern the highlights, plus a good supporting cast of Sooty Shearwaters, Arctic Terns, Common Scoters, Arctic and Great Skuas. A Wheatear on the roof of the seawatching hide hinted at a bit of passerine migration too.

Sunday looked even more promising. Flamborough was pretty foggy to start with, which lasted through until early afternoon and the sea was surprisingly quiet with no skuas at all and one only Sooty Shearwater. Ducks were the main feature, with 115 Common Scoters and 56 Teal eclipsed by a rather smart drake Velvet Scoter:

I tramped round the Old Fall loop and failed to find many migrants, with just a few Willow Warblers, Chiffchaffs and Whitethroats. There were two Pied Flycatchers around, but I missed both and the Greenish Warbler turned up to the north, at Filey, found by Yorkshire Terrier Mark Pearson - nice one mate!

To cheer myself up, I headed over to Bempton to have another look at the Black-browed Albatross which is still hanging out around the cliffs.

The bird was present on arrival, cruising around Staple Newk and attempting to land among the Gannets, which eventually she did. A feisty Gannet pushed her off a little later and she began circling the cliffs, at one point coming to within about 25 metres of where I stood - class.

I headed over to Staple Newk viewpoint and got cracking views as she looped around over the Gannetry below me. After a bit, she got tired of the commotion and glided out to sea, landing about 1km offshore on the edge of the sea fret. She drifted south slowly and disappeared into the fog.

Tuesday 10 August 2021

South-west Odyssey Part Three: Scilly Pelagic #2 - The Wilson's Rush

Had an enjoyable day with the family, down at Porthloo beach where I managed not to embarrass myself too much with my attempts at standup paddle-boarding. Time flies when you are having fun and I soon found myself back at the quay late afternoon, with Mark and Dunc, to have another crack at Wilson's Petrel on our second Scilly Pelagic. Lucy McRobert and Rob Lambert were aboard too, so I hoped they'd bring a little Zino-esque luck to the trip!

The plan this evening was to head seven miles due south, put out some fish oil and then sit in the slick and wait. Good numbers of Manxies and Common Dolphins were seen on the way out and then we stopped, dropped in the chum and waited. We calmly drifted in light seas for ages with very little happening. A couple of juvenile Yellow-legged Gulls gave us something to look at and I picked up a large shearwater which unfortunately headed off into the distance. I wasn't sure, but more confident birders felt it was a Great. 


Where was the Wilson's? Where was anything for that matter? It was very quiet. Most birders began relaxing and chatting; the collective scanning effort dwindled. We continued to work hard but we were among the minority. It felt like that famous afternoon scene on the boat in the Jaws movie, complete with the clicking of the nearby shark fisherman's reel adding perfectly to the atmosphere. Something must surely happen, but hopefully not a collossal shark trying to eat the boat.


A few Euro Storm Petrels flicked past, flashing white-striped underwings (see above), but paid no attention to the fishy slick. We began to wonder if there was enough fish oil and chum in the water - what did we know? - we had to trust the experts! A frisbee-like breaching Sunfish brightened our moods and we upped our scanning effort, although time was running out. One of the fisherman reeled in a class Red Gurnard.

Out of nowhere, I picked up a petrel coming in straight towards us. 

It looked bigger and longer-winged than the Euro Stormies we'd seen so far and so I quietly mentioned it to Dunc and suggested he get on the bird. "Looks like a Wilson's", he immediately said. Mark got on it, and then Richard Stonier. They agreed and it was announced to the boat. The angle changed; it surely had solid dark underwings; and those wings, they looked paddle-shaped - surely a Wilson's! It then banked sharply, showing mind-blowing grey covert bars, a wrap-around white rump - definite Wilson's! It flew past at close range, showing off its ample foot projection - kapow - what a brilliant little bird, a bird I had long dreamt of seeing but never really expected to. 


Wilson's Petrels. Tiny, but immense.

After its performance, it flew off, to be replaced shortly by another bird in a different wing moult. This bird came in close to the boat and then absolutely bounced across the slick, wings aloft and feet down, literally dancing across the shimmery sea surface with the iconic edifice of the Bishop Rock Lighthouse in the background adding the context. To say I was thrilled by this was clearly an understatement and demonstrates the moments of pure exhillaration pelagic birding can bring. From the doldrums straight up to cloud nine in seconds. Alton Towers doesn't get anywhere near this for adrenaline rush!

The Wilson's melted away. We headed for a deep-sea trawler to see what it's catch had attracted, which was, sadly, not a lot. Gangs of jinking Euro Stormies began heading past the Sapphire back to  their nest burrows on the Scillies. In the gathering dusk we joined them and headed for home.

A gorgeous end to a fab pair of pelagics with two of my best mates.

Bishop Rock, Wilson's Petrel and three very happy birders. (l-r: Me, Dunc and Mark)


Wilson's Petrel is still in the 'legends and enigmas' category in my mind despite its rarity status having reduced in recent years due to the discovery of regular 'wintering' populations off the Scillies and elsewhere. I recall being too young for the special pelagic trips that used to be organised in the '90s out to the 'Wilson's Triangle', perhaps the start of the discovery of this new wintering area. Those pelagics fizzled out and in their place trips aboard shark-fishing vessels out of the Scillies began, morphing into bespoke birder pelagic trips since the late '90s. Now, with a bit of planning and a bit of luck, you have a great chance of finding this tiny seabird in UK waters. 

Big up Bob Flood, Joe Pender and the Scilly Pelagic team who have really got this nailed in Scilly waters during the last 15 years and have made it possible for landlubbers like me to experience the Wilson's rush. Brilliant stuff! We are now planning our return in '22...

South-west Odyssey Part Two: Scilly Pelagic #1

The following day, we took the mighty Scillonian across to the Scillies. Plenty of Manx Shearwaters seen from the boat and a solitary Sooty Shear sitting with a raft of Manx. A couple of pods of Short-beaked Common Dolphins seen too, which was brilliant and caused a lot of excitement among the other passengers - aswell as me and the kids!

Note how in the top pic, the usually black and white Manx appear quite brown in the strong light, unlike in the bottom pic, with the Sooty Shearwater.


Arriving at St Mary's, it became apparent that the immature male Walrus had done a bunk. We kept our fingers crossed he would return...

The following day dawned calm and clear, after a restful night in the fab Garrison Campsite. I met up with Team Birdo mates, Dunc and Mark, and headed to the quay for our first Scilly Pelagic. We met Bob Flood and skipper Joe Pender before heading out on the infamous Sapphire southwest of St Mary's to Pol Bank. Pol Bank was where last year these guys found the UK's first Zino's Petrel! So fingers crossed...

On the way out, we picked up a Minke Whale, an Ocean Sunfish and several pods of Common Dolphins, among rafts of Manx Shearwaters. A good start. Eventually, we arrived at Pol Bank (which looked like every other bit of sea), stopped steaming and fish oil was poured in to the sea along with dried mealworms and bread, in order to pull in seabirds. For a while nothing happened, and then from nowhere a couple of Fulmars appeared and started to patrol the fishy slick. Shortly, I picked up a large shearwater, which on closer inspection was a spanking Great Shear. It hung around the boat for a while, sometimes coming in rediculously close. Such amazing birds, they spend their winter doing a big circuit of the North Atlantic, before heading back to South Atlantic islands to breed in our winter. 

Someone suddenly called Wilson's Petrel! I got on the bird quickly, but it was against the light and flew straight past without stopping to check out the slick. We all waited with baited breath, hoping the food would bring the bird in, but it didn't. I felt hollow and cheated - so close to a mythical bird I had really hoped to see but just not good enough to clinch. A bit of wing shape was apparent, but the bird had remained in silhouette the whole time, so I couldn't really see any plumage. Close, but no cigar.

Later on, we started steaming again and we hit on a feeding frenzy. A big raft of Manx Shears were present plus lots of Gannets and Common Dolphins. At least two Great Shears were present, one of which was diving down from the surface seeking fish. A Sooty Shearwater flew past, our sole sighting of the day. Sadly, nothing else new was added to the trip. It had been a cracking day, but I was left wanting more. Fortunately, Team Birdo were booked on the next trip, the following evening.

Great Shear snorkelling, with Common Dolphin, Gannet and Lesser Black-back.

Nice comparison between Manx (top) and Great Shears.


Monday 9 August 2021

South-west Odyssey: Part one - High Brown Fantasy

After the adrenaline-fueled mayhem and queue-induced catatonia of Alton Towers theme park, we headed further south and west to Dartmoor.  

The last time I visited these celebrated hills was searching in vain for the UK's first Bearded Vulture, back in 2016, on our way to a week's family camping in Cornwall. This year, the fabled area was again a convenient stopping-off spot on our way down to Penzance, where we planned to hop on the Scillonian for a trip to the Scillies. With some top gen from Team Birdo mate Dunc, we headed for Ashburton, close to a site for the UK's most threatened butterfly, High Brown Fritillary. The population of this butterfly has crashed by 85% since the 70s and in common with many fritillaries and other butterflies, the driver of this has been habitat loss and degradation. Much effort is being put into conserving remaining colonies such as here at Dartmoor, by Butterfly Conservation, local Wildlife Trusts, Natural England and others.

I had looked for this species before, most recently in Silverdale, without success. Sadly, as we approached Dartmoor, the leaden sky yielded rain, whilst a gusty wind shook the trees, not exactly good butterfly weather...another dip was on the cards.

As we struggled up the windy road towards Aish Tor, the dire conditions suddenly relented and the sun's rays flooded the verdant woodland. We were in with a chance! I hurried the kids up the hill from the NT car park by the river at Newbridge, with the presence of an ice cream van not helping with their motivation for a walk. Into the woods and orange shapes danced across the bramble tops- Silver-washed Fritillaries - this was a good sign! I paused for a look, before continuing up the hill.

Out on to the bracken-enveloped hillside and I saw a few orange shapes flit over the fern fronds, but none stopped, so I continued to struggle uphill. I heard lots of angry comments from the family behind me, but fortunately, a troop of Dartmoor ponies appeared, bringing smiles all round. Then it rained! Had my window of opportunity closed? Well, apparently not, as a few minutes of sheltering in some bushes later and the sun came back out. The kids by this time were waning again and demanding to head down hill for vanilla-flavoured rewards. I requested one quick look around in this moment of sunshine and Vicky kindly agreed. 

My info was that the fritillaries were to be found among the rides through the bracken, checking out violets on which to lay their eggs, or pausing to sip nectar from brambly tangles. Shorts as it turned out were not ideal, as I tramped rapidly around through brambles and bracken getting cut to shreds fueling the feeling of creeping dismay. 

I headed down the road and decided to try one last area. It seemed there had been some active management going on here, with evidence of rides (paths/trails) being cut through the bracken. Round a corner and I came across a big bramble patch and a fritillary flew straight in and landed. I had genned up on what to look for to distinguish this species from the very similar and much commoner Dark Green Fritillary, which I'd conveniently seen the previous week at Fen Bog. On the upperwing a tiny spot was out of alignment compared with the same spot on a DGF - this was going to need close views - or a photo - whilst the more prominent feature was a row of red-ringed spots on the underwing. 

Meanwhile, the fritillary casually sipped nectar a few metres away. I squinted through my bins - it was side on to me and had it's wings wide open. I looked hard for that third spot and sure enough, it looked to be out of line and small! 


But I needed to see the underwing. This was proving to be more tricky! I decided to get some pics as it occasionally flapped - if I could only get a pic as it raised its wings, maybe I could clinch it. After several attempts, one of the pics revealed those tell-tale red-ringed spots - kapow! High Brown Fritillary! 

Absolutely magnificent. Suddenly, another one appeared, landed momentarily and then glided off; glorious scenes! I ambled back down the hillside and stumbled on another, this time sitting low down on the violets. The sun went behind a cloud and the little beauty posed as I crouched down beside it, close enough to see the third spot with my naked eye. What a privelege to see such a rare insect like this. After a few magical moments, I left her doing her thing and bounced back to the car park beaming like a loon.

And a bit of phone vid:


Here is part of a High Brown Fritillary wing with indented (and tiny) third spot on the upper surface of the forewing indicated, compared with a Dark Green Fritillary (lower) from Fen Bog a week or so ago.