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Subject: Po Toi Seawatch Spring 2022 [Print This Page]
Author: badesc    Time: 25/03/2022 10:18     Subject: Po Toi Seawatch Spring 2022

Here we are with the survey reports for the spring of 2022. This season has been very well covered in the past, as it is an excellent season for seabirds and coastal migrants. However, autumn should not be forgotten, as it is very good and very birdy as well. But that’s for later this year.

Due to circumstances, I was unable to do any surveys in early March. Hence, we likely missed the peak for large gulls, such as Black-tailed and Heuglin’s. That’s a gap that we need to fill next March.
Author: badesc    Time: 25/03/2022 10:19

6 March

Akki and Roman did some seawatching on the above day, from 12h00 to 13h00. Winds were blowing from the east with force 5.

Seabirds:
17 Streaked Shearwaters

Checklist on eBird: https://ebird.org/checklist/S104268489
Count on Trektellen: https://trektellen.nl/count/view/3323/20220306

Remarks

Of course, there are no data to support this, but with the given wind conditions, I presume more shearwaters passed through the Lema Channel before and/or after the observation time. So this count is valuable as it can help us understand the occurrence of Streaked Shearwaters in spring. They might be more regular than previously presumed, or the numbers have simply increased recently.
Author: badesc    Time: 25/03/2022 10:22

13 March

My first survey for this spring could be done on Sunday 13 March. The weather was bright and sunny, with winds blowing from the northeast with a moderate force 3. I seawatched from 09h25 until 15h45.

Seabirds:
14 Ancient Murrelets

Egrets and herons:
2 Great Egrets

Gulls:
2 gulls spec.
16 Heuglin’s Gulls
1 Black-tailed Gull
1 Vega gull subspec.

Also a group of 40 Light-vented Bulbuls.

Checklist on eBird: https://ebird.org/checklist/S105120257 The Vega Gull has been submitted to eBird as “American Herring/European Herring/Vega Gull Larus argentatus”. Although we know it was not Larus argentatus and those 3 species have been split a long time ago, at least in this way we can separate Larus vegae subspec. from Larus vegae vegae and Larus vegae mongolicus.
Count on Trektellen: https://trektellen.nl/count/view/3323/20220313

Remarks

As was to be expected, we counted a new record high for Ancient Murrelets. As Geoff found out years ago, the peak for this species was/is late February and March. Hence our record count fits this pattern nicely.

The number of large gulls was surprisingly and disappointingly low.
Author: badesc    Time: 25/03/2022 10:27

15 to 17 March

Time for a 3-day survey. I started on 15 March and birded from 11h40 until 18h00. The weather was not particularly inviting for seabirds, with basically a flat sea (force 1 from the east). Only the last hour we experienced a little more wind, but not enough and too late to get things moving. It was also quite sunny.

Actually, the highlight was a total of at least 55 dolphins that moved through the Lema Channel to the northeast. They could be very easily seen due to the flat sea and some were also spotted by others from the ferry.

Seabirds:
1 Ancient Murrelet
1 Red-necked Phalarope

Egrets and herons:
1 Great Egret

Ducks:
63 ducks spec.

Gulls:
56 gulls spec.
69 Heuglin’s Gulls
47 Black-headed Gulls
3 Black-tailed Gulls
1 Vega Gull subspec.

Swift(lets), swallows and martins:
7 Barn Swallows

Checklist on eBird: https://ebird.org/checklist/S105464784
Count on Trektellen: https://trektellen.nl/count/view/3323/20220315

The weather on 16 March was a lot better, with force 4 winds blowing from the northeast, mainly cloudy, with a few sunny intervals and reasonably good visibility. I seawatched the whole day, from 06h40 until 18h00.

Seabirds:
124 Streaked Shearwaters
35 Red-necked Phalaropes
7 Long-tailed Jaegers
3 Ancient Murrelets

Ducks:
1 Tufted Duck

Waders:
101 waders spec.
1 sand plovers spec.
2 Oriental Pratincoles

Gulls:
22 gull spec.
17 Heuglin’s Gulls
1 Black-tailed Gull

Terns:
7 Common Terns
2 Greater Crested Terns

Checklist on eBird: https://ebird.org/checklist/S105465084
Count on Trektellen: https://trektellen.nl/count/view/3323/20220316

But the weather on 17 March turned less favourable, again, with eastern winds but only force 2. Partly (and mostly) sunny, partly cloudy.

Seabirds:
139 Red-necked Phalaropes
1 Ancient Murrelet

Egrets and Herons:
3 Great Egrets

Waders:
95 waders spec.
25 March Sandpipers

Gulls:
9 gulls spec.
2 Black-tailed Gulls
2 Heuglin’s Gulls

Terns:
1 tern spec.
1 Common Tern

Swift(lets), swallows and martins:
1 Pacific Swift
5 Barn Swallows

Remarks

The unidentified ducks were probably mostly/all Garganeys, but they were too far and the lighting was bad to be certain.

The sighting of 47 Black-headed Gulls was the first sizable number of this species this year. In January and February, we only saw 1 to 7 individuals on 4 observation days.

Black-tailed Gulls must have passed during the first two weeks of March, when we were not there. That’s the usual peak for this species anyway. The numbers we recorded during this survey were very low.

Both the Common and Greater Crested Terns on 16th were new earliest dates for Hong Kong, the previous earliest date being 21 March.
Author: badesc    Time: 25/03/2022 10:52

20 to 22 March

We didn’t wait long for yet another 3-day survey. The weather looked very good when we started to make plans, but eventually it seemed that only the first day would be interesting and the next two days I was afraid I would encounter little wind, much fog and no birds. Luckily, Geoff convinced me to stay for 3 days and I’m glad I followed his suggestion!

As 20 March was a Sunday, I took the first ferry at 08h15 and started seawatching from Po Toi at 09h45 to 18h10. I was joined by Abdel, Akki and Roman for about an hour. It was cloudy, with some drizzle and two showers before noon. Afternoon turned dry. Winds blew from the northeast with force 4 to 5. It turned out to be an excellent day.

Seabirds:
1 all-dark shearwater, possibly Flesh-footed
155 Streaked Shearwaters
438 Red-necked Phalaropes
1 jaeger spec.
10 Pomarine Jaegers

Gulls:
7 gulls spec.
40 Heuglin’s Guls
1 Vega Gull subspec.

Terns:
28 Greater Crested Terns

Swift(lets), swallows and martins:
4 Barn Swallows

Checklist on eBird: https://ebird.org/checklist/S105465565
Count on Trektellen: https://trektellen.nl/count/view/3323/20220320

Also the second day, 21 March, was truly extraordinary good for seawatching. I had the whole day, from 06h30 to 18h00. It was cloudy again, with a very small effort for some sunshine in the afternoon. Dry and foggy. Winds came from the northeast, with force 4.

Seabirds:
479 Streaked Shearwaters
1 Flesh-footed Shearwater
17 Red-necked Phalaropes
1 jaeger spec.
5 Pomarine Jaegers
1 Parasitic Jaeger
2 Ancient Murrelets

Waders:
1 sand plover spec.

Gulls:
4 gulls spec.
75 Heuglin’s Gulls
1 Vega Gull subspec.

Terns:
31 Greater Crested Terns
2 Common Terns

Swift(lets), swallows and martins:
28 Barn Swallows

Checklist on eBird: https://ebird.org/checklist/S105465798
Count on Trektellen: https://trektellen.nl/count/view/3323/20220321

The last day of this surveys, 22 March, turned out as expected: little wind, much fog and very few birds. The weather was still cloudy, but with at times thick mist. So, visibility was limited to 2km at most, and sometimes not more than 500m. Winds came from the north, turning east, force 2 to 3.


Misty conditions off Po Toi

Seabirds:
4 Streaked Shearwaters
127 Red-necked Phalaropes
2 Parasitic Jaegers

Waders:
2 waders spec.
1 Little Ringed Plover
1 Oriental Pratincole

Gulls:
15 Heuglin’s Gulls

Terns:
8 Greater Crested Terns

Swift(lets), swallows and martins:
5 Barn Swallows

Checklist on eBird: https://ebird.org/checklist/S105466268
Count on Trektellen: https://trektellen.nl/count/view/3323/20220322

Remarks

Some background on the Flesh-footed Shearwater, of course. After all, if accepted, this is the first record for Hong Kong.

I saw it first on 20th going west with a bunch of Streaked Shearwaters, but flying alone and further out. It was clearly all-dark, including the underwings, apart from what appeared to be a light patch on the base of the primaries on the underwings. This reminded me of Providence Petrel, but not more than that. Actually, as I would discover later, it was (probably) moulting inner primaries that created this effect, and it indicates how far the bird must have been. Bill and legs/feet were therefore invisible.

It appeared rather similar to Streaked Shearwater, which was seen at the same moment: a robust shearwater. Relatively slow and few wingbeats; long, high arcs (higher than Streaked); tail certainly not particularly long; head and neck big/strong, as Streaked. No sunlight shining on underwings, but white/grey of typical Sooty and even Short-tailed should probably have been seen, I believe (but note that some individuals of both these species can show all-dark underwings!). Too powerful/heavy for Short-tailed. Lacking long tail of Wedge-tailed.

So, my best guess was likely Flesh-footed. All characters fitted this species better than any other. But for a first for HK, the bird was too far and not seen well enough (although quite long). And I had no photos.

Yann Muzika commented that Flesh-footed arrives in Japan in March and is often seen as singles together with Streaked, Short-tailed and/or Sooty Shearwaters. He suggested trying again the next day, which I surely did.

As many as 479 Streaked Shearwaters flew west the next day between 08h50 and 09h10 and amongst them, indeed, again an all-dark shearwater. But it was even further than on the previous day. However, I had good hope it might return later in the day.

Around 16h00, after already a few hundred Streaked had moved northeast, many were also feeding and I noticed a group right in front of the watch point, just a few hundred meters away. So, I grabbed my camera to take some photos and film the shearwaters.

This is the clip https://youtu.be/jfRrwWAi8sU (if you want best quality views, change the settings manually to 2160p 4K). Do you note a dark shearwater flying-by, certainly two times? Well, at the moment I was filming, I did not! But soon after I saw it with bins or scope and it also landed on the water. After it took off and flew northeast, I could catch it on film as well: https://youtu.be/y5o-hOA8E74.

Later and on photos, I noticed the bird showed pinkish legs/feet, making it a full 100% certain that it was a Flesh-footed Shearwater. I don’t think I could have wished for any better views and circumstances to claim a new species for Hong Kong, a seabird seen several times – far and close – , flying and sitting, and being able to photograph and film it. Many seabirds fly-by further away and are gone in a matter of a few minutes.


Flesh-footed Shearwater (below) with Streaked Shearwater, 21 March 2022, Po Toi


Flesh-footed Shearwater, 21 March 2022, Po Toi


Flesh-footed Shearwater, 21 March 2022, Po Toi

In case you wonder, I’m using a Canon R6 camera and a Canon 800mm/f11 lens. After having tried different cameras and lenses and a digiscope set-up, this combination seems to give the best results. But photographing and filming seabirds from land is far from straightforward and often impossible.

The number of Streaked Shearwaters was also truly unprecedented. And I saw many looking for food, diving with their heads in the water and carrying prey in flight.

Let me show you the counts during certain times on both 20th and 21st respectively:



We cannot add all the counts on 20th, because many also returned to northeast. The counts are just to show the movement of groups within a relatively short time.

Same goes for 21st, as the group first flew northeast, to than return to west, to finally fly to northeast during the day after 10h14.

Lots of Streaked Shearwaters have also been seen from the ferry at times in the recent past.

The first Parasitic Jaeger of spring appeared on 21 March. This was also the earliest date for Hong Kong in the past. Yet, I was expecting this species earlier.

Speaking of jaegers, with quite a few Long-tailed and Pomarine Jaegers seen, we could observe the difference in behavior. Not that the two in particular are confusing (it’s rather Pomarine with Parasitic, or Parasitic with Long-tailed), and there is also overlap in behavior. But Pomarine can stand strong headwinds and flies very powerful and fairly fast against the wind. Even when gulls obviously struggle with that. It’s like nothing can stop a Pomarine. Long-tailed certainly can fly straight ahead as well, but often less in a straight line like Pomarine. In most of the Long-tailed Jaegers seen – and in less strong winds – they take their time, regularly turning back, landing on the sea, picking up food, flying high, then low.

These behaviours are nothing new and are mentioned in field guides. Just thought it would be interesting to mention this here.

[ Last edited by badesc at 25/03/2022 17:52 ]

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Author: wcaptain    Time: 25/03/2022 15:44



Flesh-footed,,,, a great find
Author: badesc    Time: 28/03/2022 15:56

27 March

The weather on 24, 25 and 26 March actually looked really good, but I can’t be seawatching every day. And after such a good previous survey, the plan was to go on Sunday 27 March. The weather was not that good, in the sense that the sea looked pretty flat from the ferry. But in the Lema Channel, northeasterly winds were however blowing with force 4. It was cloudy, with some drizzling, but mainly dry. Some foggy periods, although visibility was pretty good most of the time. It was starting to get cooler. I watched from 09h30 until 17h15.

Seabirds:
56 Streaked Shearwaters
5 Parasitic Jaegers
109 Red-necked Phalaropes

Egrets and herons:
16 egrets spec.
1 Eastern Cattle Egret
1 Great Egret

Waders:
2 Common Greenshanks
16 Oriental Pratincoles

Gulls:
30 gulls spec.
34 Heuglin’s Gulls
1 Black-headed Gull
1 Black-tailed Gull

Terns:
2 terns spec.
49 Greater Crested Terns
33 Common Terns

Swift(lets), swallows and martins:
20 Barn Swallows

Checklist on eBird: https://ebird.org/checklist/S105754416
Count on Trektellen: https://trektellen.nl/count/view/3323/20220327

Remarks:

Two things stood out for me. The first is that there was a cold front coming and many gulls were flying to the west. From what we observed, it seems that they are sensitive to temperature drops in spring. Jaegers, pratincoles, waders, egrets and Greater Crested Terns all flew to the northeast. The Common Terns flew to the west as well.

And secondly, the number of Greater Crested Terns was decent, even when the peak of their spring migration is in April. So, expect the numbers to go still higher from here.

[ Last edited by badesc at 28/03/2022 16:07 ]
Author: badesc    Time: 5/04/2022 20:27

29 to 31 March

As we want to squeeze the maximum out of March, we did another survey on the three last days of the month. I personally think March is a bit underestimated and regarded as too early for good birds. Yet, it can be a very rewarding month.

Arriving at the seawatch point on 29 March, I started counting at 11h25 and until 18h10. I was joined by Martin Williams until 13h30, and he found quite a few birds that I would have missed (see also remarks, below). The weather was good and the sea looked nice as well. Winds were blowing from the northeast with force 4 (maybe up to 5 at one point) and it was cloudy with clear views

Seabirds:
2 Brown Boobies
3 jaegers spec.
5 Parasitic Jaegers
117 Red-necked Phalaropes

Egrets and herons:
14 egrets spec.
23 Little Egrets
4 Eastern Cattle Egrets
3 Great Egrets

Ducks:
1 duck spec.
28 Garganey

Waders:
23 waders spec.
5 Greater Sand Plovers
2 Oriental Pratincoles

Gulls:
26 gulls spec.
117 Heuglin’s Gulls
3 Black-tailed Gulls
1 Vega Gull subspec.

Terns:
2 terns spec.
24 Greater Crested Terns
6 Gull-billed Terns
1 Whiskered Tern

Swift(lets), swallows and martins:
27 Barn Swallows

Passerines:
1 White Wagtail

Checklist on eBird: https://ebird.org/checklist/S105995320
Count on Trektellen: https://trektellen.nl/count/view/3323/20220329

As always with 3-day surveys, the second day, 30 March, was the only full day. So, I watched from 06h20 until 18h00. Winds still came from the northeast with force 4, but it was partly sunny and with some foggy periods. This was a very nice day with more different species and good numbers of migrants.

Seabirds:
23 Streaked Shearwaters
8 Parasitic Jaegers
4 Ancient Murrelets
601 Red-necked Phalaropes

Egrets and herons:
44 Little Egrets
2 Great Egrets

Waders:
50 waders spec.
5 Pacific Golden Plovers
1 Grey Plover
6 sand plovers spec.
13 Lesser Sand Plovers
3 Greater Sand Plovers
3 Oriental Pratincoles
16 Great Knots
16 Red-necked Stints
6 Curlew Sandpipers
1 Sharp-tailed Sandpiper

Gulls:
68 gulls spec.
267 Heuglin’s Gulls
3 Vega Gulls subspec.
1 Black-tailed Gull

Terns:
4 terns spec.
114 Greater Crested Terns
6 Little Terns
5 Common Terns
3 Gull-billed Terns
1 Caspian Tern

Swift(lets), swallows and martins:
1 Pacific Swifts
16 Barn Swallows

Checklist on eBird: https://ebird.org/checklist/S105995872
Count on Trektellen: https://trektellen.nl/count/view/3323/20220330

On the last day, 31 March, the weather wasn’t really ideal. Cloudy in the morning, but soon turning bright and sunny, and that meant bad lighting, which left birds unidentified. No different in winds from the previous, still blowing from the northeast with force 3 to mainly 4.

Seabirds:
3 Parasitic Jaegers
456 Red-necked Phalaropes

Egrets and herons:
8 egrets spec.
4 Little Egrets
2 Great Egrets
2 Eastern Cattle Egrets

Waders:
38 waders spec.
2 Eurasian Curlews
2 Common Redshanks
1 Oriental Plover
3 Pacific Golden Plovers
9 sand plovers spec.
3 Lesser Sand Plovers
1 Kentish Plover
6 Dunlins

Gulls:
38 gulls spec.
72 Heuglin’s Gulls
3 Black-tailed Gulls

Terns:
11 terns spec.
27 Gull-billed Terns
19 Greater Crested Terns
1 Little Tern

Swift(lets), swallows and martins:
5 Pacific Swifts
3 Barn Swallows

Passerines:
1 Olive-backed Pipit

Checklist on eBird: https://ebird.org/checklist/S105996128
Count on Trektellen: https://trektellen.nl/count/view/3323/20220331

Remarks

Many migrant birds – it seems to be the majority – fly along a curved axis northeast – west. But some come from the south and fly north, like Barn Swallows, swifts and passerines. They arrive from the sea over a broad front and when I just watch the sea and fix on one point, many pass to my left and right and go along unnoticed. Martin picked-up quite a few of these birds on 29th.

Then egrets don’t fly over Po Toi but, probably coming from the south as well, make a bend for the northeast or for the northwest. Especially those flying to the northwest are migrants that I miss easily, and were picked-up by Martin. Plus, there will also be raptors that fly-over high, again birds that I won’t see while scanning the sea.

So, we have a bunch of birds that I miss while seawatching. But then, I (hopefully) get most of the seabirds, waders, ducks, gulls and terns (except some of the ones that fly high, or low and very close).

Just to say that my counts consist only of a portion of what moves through the area…

The two Brown Boobies was the first record for Hong Kong of two individuals together. All previous records were singles on one day.

Interestingly, they confirmed that the vast majority of migrants coming from the northeast make a bent to the west and don’t fly straight to the southwest. The boobies did fly to the southwest and were an exception. I saw them first while scanning to the far northeast and decided to follow them for as long as possible. This took about 8 minutes. But the more they flew to the right of me (I looked southwards), the more I started to see them from behind. They eventually disappeared to the left of, but slightly towards, the red lightboat, which is positioned to the southwest of the watch points. If the boobies would have flown south, they would have reached the Dangan Islands. If they would have flown to the west, they would have made the bent and flown in front of (or behind) the red lightboat, crossing it while still be seen from their side, not from their back.

It sounds odd, but almost all southbound migrants make a bent to the west, not flying southwest. They seem to disappear between Lamma Island and Wailingding Island. Many northbound migrants come from the same area. It’s a subject for a further write-up, but before that further investigation as well.

The count of more than 600 Red-necked Phalaropes was a good one. We counted over a thousand individuals on this survey, making it by far the commonest bird.

Another very good count was the 114 Greater Crested Terns. This is the highest number ever for March, and the second highest number of any month (see https://trektellen.nl/species/records/0/3323/693/0 for counts from 2021 onwards). It opens the possibility that we might see over 200 individuals on a good day in April, when numbers in spring tend to peak.

Species such as ducks and especially waders flew-by at close range during our survey, hence many were identifiable. This has not always been the case in the past, due to a combination of distance and bad lighting. E.g., we finally saw most Garganeys close, and even landing on the sea.
Author: badesc    Time: 5/04/2022 20:30

March 2022

Let’s wrap-up March, using data from Trektellen. From all observers, there were a record of 6 surveys, with 3 full days and 9 half/partial days. This resulted in total observation time of 93 hours and 55 minutes, also a record since the currents surveys started last year.

It was a very good month; those hours were well rewarded. 49 species were seen, both birds present and migrating. For migrants only, the number was 44. It was certainly a month in which spring migration greatly increased, with more egrets, waders and terns showing up.

We counted a total of 5,344 birds. Actually, we did not necessarily count this number of individuals, as a species like Streaked Shearwater lingered around for 3 days and we most probably saw the same individuals more than once. But the number of 5,344 is also not that far from reality.

The most common species was Red-necked Phalarope, with 2,040 migrating birds counted. Second was Heuglin’s Gull, with 714 birds. And, surprisingly, the third commonest species was Streaked Shearwater, with 699 birds counted (this number excludes counts on 2 days to reduce the chance of double counts).

Noteworthy is also a total of 275 Greater Crested Terns, 24 Parasitic, 15 Pomarine and 7 Long-tailed Jaegers, and 23 Ancient Murrelets, with a record count of 14 on 13th.

Apart from birds, heat haze was very limited, lighting conditions were still challenging during sunny days, there were quite a few foggy days and the number of mosquitoes at the watch points was annoyingly high. And we saw a total of 55 dolphin’s migrating through the Lema Channel.

I’ve mentioned in recent posts that things would only get better as spring migration moves on. This still holds true. March was just a warm-up. According to previous research, conducted by Geoff Welch, we might expect the peak migration in the last two weeks of April and the first week of May.

[ Last edited by badesc at 6/04/2022 07:34 ]
Author: badesc    Time: 5/04/2022 20:33

3 April

Our first survey for April was on the first Sunday of the month, 3 April. Although the month is promising, that doesn’t mean every single day is amazing. There are good days and not so good days. And our first Sunday was indeed rather calm, but still with a variety of migrants.

I arrived at 09h30 and watched until 17h15. The weather wasn’t ideal, being bright and sunny, but with very clear views. Winds were initially blowing from the north with force 4, but soon turned to northeast with an increased force 5.

Seabirds:
1 jaeger spec.
29 Red-necked Phalaropes

Ducks:
12 Garganeys

Egrets and herons:
5 egrets spec.
3 Eastern Cattle Egrets

Raptors:
1 Peregrine Falcon

Waders:
15 waders spec.
4 Grey Plovers
3 Pacific Golden Plovers
2 Common Redshanks
1 Eurasian Whimbrel

Gulls:
25 gulls spec.
98 Heuglin’s Gulls
1 Vega Gull subspec.
1 Mongolian Gull
1 Slaty-backed Gull

Terns:
33 terns spec.
11 Greater Crested Terns
1 Black-naped Tern
1 Whiskered Tern

Swift(lets), swallows and martins:
8 Barn Swallows
2 Red-rumped Swallows

Checklist on eBird: https://ebird.org/checklist/S106242148
Count on Trektellen: https://trektellen.nl/count/view/3323/20220403

Remarks

Having seen already quite a few seabirds earlier this spring, like phalaropes, jaegers, murrelets, 100’s of shearwaters, and 2 Brown Boobies, I was hoping that the increased winds, turning to the northeast, would result in more seabirds. But this was not the case at all. How birds react to weather and changes to it, remains partly unpredictable. But generally, strong easterly winds are good. We’ll see next time.

The Black-naped Tern was a new earliest date for Hong Kong, the previous earliest date was 6 April.
Author: John Holmes    Time: 6/04/2022 18:52     Subject: April Seabirding results

Hi Bart,

A solid start to April.  Here’s hoping for more great sightings this spring !

John
Author: badesc    Time: 12/04/2022 19:14

10 April

The weather had been clear and sunny for the whole week, so it was interesting to see how many migrants and seabirds we would see on Sunday 10 April. I could watch from 09h10 until 17h10. The weather was still sunny, with northeast winds decreasing from force 4 before noon to 3 after noon.

Seabirds:
5 Ancient Murrelets
24 Red-necked Phalaropes

Ducks:
22 Garganeys
Egrets and herons:
11 egrets spec.
3 Eastern Cattle Egrets
1 Little Egret

Waders:
8 Oriental Pratincoles

Gulls:
4 gull spec.
10 Heuglin’s Gulls
2 Black-tailed Gulls

Terns:
9 terns spec.
79 Greater Crested Terns
37 Gull-billed Terns
34 Common Terns
6 Whiskered Terns
3 Little Terns
1 Aleutian Tern

Swift(lets), swallows and martins:
3 Barn Swallows
1 Pacific Swift

Checklist on eBird: https://ebird.org/checklist/S106760731
Count on Trektellen: https://trektellen.nl/count/view/3323/20220410

Remarks

As soon as I looked through my scope, there were migrants. But the activity decreased rather soon and it seemed as if we were only able to see the ‘tail’ of the usually quite busy morning hours (first three hours). For the rest of the day, we continued to see birds passing-by, but it was never really busy. On the one hand, Sunday surveys can produce good results and certainly a chance for good species. Many rare/scares species or good numbers have been seen after 9AM. But on the other hand, we also miss the busy morning hours, which are an important part of the day. We therefore can only collect partial data and the real numbers for the full day should be, or at least could be, substantially higher.

We counted more than 250 birds, with the fine weather. No drama, but I think that’s much less than we potentially might count in April with other weather conditions: windier, cloudier, some showers,… And surprisingly, the next day, a Streaked Shearwater and 3 jaegers were seen near Po Toi. The weather was even less compelling for seabirds, with hardly any wind on again a sunny day.

The weather and the occurrence or absence of seabirds remains very interesting and often attracts our attention. But we need to recognize that it is only partly predictable what one might see and surprises are very frequent.
Author: badesc    Time: 21/04/2022 14:33

15, 16, 17 and 18 April

The survey during the Easter holidays was done by coming to and leaving Po Toi every day. It’s far from ideal, not in the least because we miss the three first busy morning hours and also the last hour of the day. On every of the above days, migrant birds appeared in my scope view within seconds, while they were also flying by in the last minutes on every day. The number of birds could/should be materially higher than what was counted during only 8 hours/day.

Easter was quite busy with people as well, so a good point was that the ferry left earlier and on 15 April I could start seawatching at 09h05, until 17h15. The weather was mainly cloudy, partly sunny, but with strong, force 6 winds from the east. The winds decreased to force 5 in the afternoon.

Seabirds:
3 jaegers spec.
7 Parasitic Jaegers
3 Pomarine Jaegers

Egrets and herons:
7 egrets spec.
1 Great Egret

Waders:
6 waders spec., curlew spec.
2 Oriental Pratincoles

Gulls:
3 Heuglin’s Gulls

Terns:
31 terns spec.
71 Aleutian Terns
58 Greater Crested Terns
19 White-winged Terns
7 Gull-billed Terns
6 Common Terns
4 Caspian Terns
2 Bridled Terns
1 Little Tern
1 Black-naped Tern

Swift(lets), swallows and martins:
2 Pacific Swifts
1 Little Swift

Checklist on eBird: https://ebird.org/checklist/S107442915
Count on Trektellen: https://trektellen.nl/count/view/3323/20220415

16 April turned out to be even windier, with full force 6 easterly winds on a cloudy day. The number of seabirds was higher, but the number of terns – which struggled against the strong winds – was lower. I watched from 09h10 until 17h15.

Seabirds:
10 Streaked Shearwaters
1 Brown Booby
24 Red-necked Phalaropes
21 jaegers spec.
15 Parasitic Jaegers
2 Long-tailed Jaegers

Egrets and herons:
27 Eastern Cattle Egrets
11 Little Egrets
1 Great Egret

Waders:
17 waders spec.
11 Eurasian Whimbrels
7 Far Eastern Whimbrels
1 Oriental Pratincole

Gulls:
1 Heuglin’s Gull

Terns:
18 terns spec.
56 Aleutian Terns
35 Greater Crested Terns
4 Common Terns
2 Gull-billed Terns

Swift(lets), swallows and martins:
11 Barn Swallows
9 Pacific Swifts

Checklist on eBird: https://ebird.org/checklist/S107443083
Count on Trektellen: https://trektellen.nl/count/view/3323/20220416

Still windy on 17 April, but a bit less, force 5 to 6. Cloudy as before. I was on duty from 09h10 to 17h15.

Seabirds:
5 Streaked Shearwaters
12 jaegers spec.
25 Parasitic Jaegers
1 Long-tailed Jaeger
46 Red-necked Phalaropes

Egrets and herons:
1 egret spec.
14 Eastern Cattle Egrets
3 Little Egrets
2 Black-crowned Night Herons

Raptors:
3 Grey-faced Buzzards
1 Western Osprey
1 falcon spec.

Waders:
26 waders spec.
32 Eurasian Whimbrels
3 Eurasian Curlews
2 Far Eastern Curlews

Terns:
68 terns spec.
80 Little Terns
72 Greater Crested Terns
33 Aleutian Terns
31 Common Terns
4 Gull-billed Terns
3 White-winged Terns
1 Whiskered Tern
1 Bridled Tern

Swift(lets), swallows and martins:
23 Barn Swallows
1 Pacific Swift

Checklist on eBird: https://ebird.org/checklist/S107443204
Count on Trektellen: https://trektellen.nl/count/view/3323/20220417

18 April was by far the most birdy day, with almost 830 individuals counted. Less wind, force 5 from the east turning to force 4 from the north, might had something to do with this. Still cloudy.

Seabirds:
1 Short-tailed Shearwater
9 jaegers spec.
5 Parasitic Jaegers
1 Pomarine Jaeger
1 Long-tailed Jaeger
40 Red-necked Phalaropes

Egrets and herons:
4 egrets spec.
15 Eastern Cattle Egrets
3 Little Egrets

Raptors:
31 Grey-faced Buzzards
1 Western Osprey

Waders:
1 wader spec.
50 Red-necked Stints
28 Eurasian Whimbrels
1 Oriental Pratincole

Gulls:
1 Heuglin’s Gull
2 Black-tailed Gulls

Terns:
95 terns spec.
185 Aleutian Terns
180 Little Terns
91 Common Terns
40 Greater Crested Terns
12 Black-naped Terns
4 Bridled Terns
3 Gull-billed Terns
1 Whiskered Tern

Swift(lets), swallows and martins:
18 Barn Swallows
1 Pacific Swift
1 House Swift

Passerines:
1 White Wagtail

Checklist on eBird: https://ebird.org/checklist/S107443336
Count on https://trektellen.nl/count/view/3323/20220418

Remarks

Maybe thanks to the strong easterly winds, passage of jaegers was prominent, with 105 in total over the four days:

45 jaegers spec.
52 Parasitic Jaegers
4 Pomarine Jaegers
4 Long-tailed Jaegers

They usually were seen early after the start of a survey, possibly indicating that more must have passed in the earlier hours. Then the numbers would slow down around noon and pick up in the afternoon, until I left. Actually, I’d say roughly 25% passed between the start and 13h00 and 75% after 13h00.

The 25 Parasitic Jaegers on 17th was a new high count for Hong Kong, the previous one was 16 on 2 May 1999 during Typhoon Leo. Note that I thought most jaegers spec. were Parasitic as well, but the other two species (especially Pomarine) could not be excluded due to the distance.

Tern movement was good, noticeably when winds were a bit reduced. I’ve witnessed this last autumn, when thousands of terns passed Po Toi on calm, sunny days. For the numbers of other species, the effect of more or less wind during this Easter survey seemed less obvious. Except for seabirds, with higher numbers on the windiest days. More specifically on the second and third windy day.

The 180 Little Terns was a new high count since 2000. It was remarkable that we saw just one on 15th, none on 16th, then 80 on 17th and 180 on 18th. It makes you wonder what the numbers might have been in the subsequent days: still higher, or lower again?

Our peak count of 180 Aleutian Terns was higher than peak counts in most previous years as well. But if many terns pass through during calmer weather, would we have seen more during our Easter survey if it wouldn’t have been that windy? Hard to tell, as in the past, peak counts usually were weather related and some occurred during even stronger winds. So, for terns in particular, you perhaps may wish either calm weather, or a storm. Birds and weather remain a complex matter to me.
Author: badesc    Time: 28/04/2022 15:18

25 and 26 April

This very short, one and a half day survey, will be our last for April. At least we had a full day, but this is the only one for April. We’ll discuss it when we summarize the month, below.

The weather on 25 April was mostly sunny, with light winds – force 2 – from the south. I could fill the day with continuous seawatching, from 05h55 until 18h10.

Seabirds:
1 Streaked Shearwater
12 Short-tailed Shearwaters
1 Brown Booby
241 Red-necked Phalaropes
43 Parasitic Jaegers

Egrets and herons:
13 egrets spec.
14 Eastern Cattle Egrets
3 Great Egrets
1 Little Egret

Waders:
88 waders spec.
61 Eurasian Whimbrels
3 Oriental Pratincoles
2 Common Redshanks

Gulls:
2 Black-tailed Gulls

Terns:
142 terns spec.
336 Common Terns
179 Aleutian Terns
127 Greater Crested Terns
33 Little Terns
32 Gull-billed Terns
24 Black-naped Terns
21 Bridled Terns
3 White-winged Terns
3 Whiskered Terns

Swift(lets), swallows and martins:
2 Pacific Swifts

Checklist on eBird: https://ebird.org/checklist/S108180314 (Good news from this site, as now more of our sightings have finally been included and are viewable via ‘Bar Charts’ https://ebird.org/barchart?r=L1239962&yr=all&m=, although quite a few are still missing. So, Trektellen is the only fully up-to-date site.)
Count on Trektellen: https://trektellen.nl/count/view/3323/20220425

26 April was a day with similar weather, although it was hotter and a little bit windier, force 2 to 3. Some fog in the early morning was gone within an hour. Migration peaked between 06h00 and 09h00 and afterwards numbers of migrants were very low.

Seabirds:
8 Short-tailed Shearwaters
1 Brown Booby
123 Red-necked Phalaropes
8 Parasitic Jaegers

Egrets and herons:
3 Eastern Cattle Egrets

Waders:
3 waders spec.
16 Eurasian Whimbrels
1 Ruddy Turnstone

Gulls:
1 Slaty-backed Gull

Terns:
62 terns spec.
111 Common Terns
79 Aleutian Terns
62 Gull-billed Terns
35 Little Terns
30 Greater Crested Terns
18 Bridled Terns
3 Whiskered Terns
2 Black-naped Terns

Swift(lets), swallows and martins:
2 Barn Swallows

Checklist on eBird: https://ebird.org/checklist/S108181185
Count on Trektellen: https://trektellen.nl/count/view/3323/20220426

Remarks

Especially 25th turned out to be an excellent day. No less than 1,387 migrants were counted, with a few interesting ones.

43 Parasitic Jaegers is a new highest count for Hong Kong. The previous record count was 25 on 17 April 2022, and before that it was 16 on 2 May 1999 at Cape D’Aguilar during typhoon Leo. Shouldn’t a typhoon bring in a lot more seabirds, such as Parasitic Jaegers, then on a day with barely force 2 winds? Probably yes, but there is an explanation.

The record at the Cape is well documented on pages 185-188 of the HKBWS Bird Report 1999-2000 (https://www.hkbws.org.hk/web/chi ... eport_protected.pdf). It’s especially noteworthy that actually 80 jaegers were seen that day and that “at least half appeared to be Parasitic”. Note that, as mentioned higher in this tread, we recorded 45 jaegers spec. out of 105 seen during our Easter survey, when winds were strong. That’s 43% unidentified jaegers, which I felt most were Parasitic as well. Coincidently (or not), these results are very comparable to what was observed at the Cape on 2 May 1999. But we did not encounter typhoon-like circumstances, which of course can hinder identification materially. On the other side, the weather on 25 April was excellent for finding, following and identifying seabirds, on basically a flat sea. And all jaegers were relatively close, making identification straightforward for everyone of them. Another point is that Po Toi should be even better than Cape D’Aguilar. It’s a pity hardly any seawatchers go to the Cape these days, as it actually would be most interesting to compare results and, especially, add both counts to get a better picture of how many birds pass Hong Kong waters. There were most probably more Parasitic Jaegers on 2 May 1999 than – due to difficult circumstances – could be recorded with certainty. And even a lot more might have moved trough the Lema Channel that day, but we’ll never know. Anyway, our record count of 43 should in reality not be the highest that has ever passed Hong Kong and therefore most probably not that exceptional. Further seawatching surveys, in different weather conditions, might continue to shed new light on this.

127 Greater Crested Terns is the second highest count for Hong Kong. The record is still 165 on 10 September 2021. 336 Common Terns is the highest-ever count on Po Toi, the previous record count was 330 on 5 May 2006. Our count of 336 is also the highest for Hong Kong this century. As mentioned before, I’ve experienced good tern migration on calm, sunny days, and this also was the case during the survey. Not to conclude anything definitely, just an observation.

The Slaty-backed Gull, a very typical individual, was the latest spring record for Hong Kong. The previous latest record was 22 April.

We recorded fairly good numbers of Short-tailed Shearwaters; they should peak in May. The highest counts in previous years has been 13 (2010), 14 (2006) and 15 (2007 and 2008). I know making predictions can be daring, but I do believe that the record count of 15 will easily be broken on a 12-hour seawatch day next May. Let’s call it a goal, anyway. Onshore winds do not seem to be necessary to see this oceanic bird off Po Toi (many even come close), but I’m looking forward in what conditions a potential new high count will be established.

Finally, I made this video of the Brown Boobies, Parastic Jaegers and a Short-tailed Shearwater: https://youtu.be/i08SYs7RWYs.

[ Last edited by badesc at 14/05/2022 10:24 ]
Author: badesc    Time: 28/04/2022 15:20

April 2022

Let’s wrap-up April, using data from Trektellen. Personally, it has been a disappointing month, due to different reasons. Not for birds, but for the lack of full day surveys. Although I’ve seawatched on 8 days, only one was a full day. One was a half day and the others were days on which I took the ferry and returned to Aberdeen on the same day. These were 8-hour days, missing the three crucial morning hours. The total observation time for the month was therefore only 67 hours and 45 minutes. I was rather planning for at least 100 hours, which April certainly deserves. Maybe next year.

We counted 46 migrant species (that’s without the specs., like ‘gull spec.’). Adding them up, we do get nice numbers, but of course we must have missed a ton of birds. Still, so much passes-by unnoticed… We counted not more than 4,314 migrants, which is also less than in March, and that should not be the case as April is better. This is due to less observation hours and missing the morning hours on all but two survey days.

16 Streaked Shearwaters
21 Short-tailed Shearwaters
3 Brown Boobies
526 Red-necked Phalaropes
9 Far Eastern Curlews
46 jaegers spec.
103 Parasitic Jaegers
4 Pomarine Jaegers
4 Long-tailed Jaegers
147 Gull-billed Terns
452 Greater Crested Terns
332 Little Terns
604 Aleutian Terns
613 Common Terns

You can check out all the numbers at https://trektellen.nl/site/totals/3323/2022/4/0.

Let’s hope for some catch-up in May…
Author: badesc    Time: 30/05/2022 14:34

1 and 2, and 3 to 8 May

As we had some serious catching up to do in May, we started right away, with two days when we returned on the same day with the ferry and then 6 days in a row. Especially the fact that we had four full days and five mornings at our disposal, meant that we could observe and count birds for several days in a row.

1 May was a day with both rain and dry periods, with northerly winds, force 5 to 6. With only about 20°C and this kind of weather, it was actually the fall of landbirds that was most striking. There was little movement of seabirds and terns. But we missed the three first hours, and then it’s always dangerous to draw firm conclusions. I watched from 09h25 until 17h05.

Seabirds:
59 Red-necked Phalaropes
1 Short-tailed Shearwater
Egrets and herons:
3 Great Egrets
3 Little Egrets
52 Eastern Cattle Egrets

Raptors:
55 Chinese Sparrowhawks

Waders:
39 waders spec.
5 sand plovers spec.
1 Eurasian Whimbrel

Terns:
8 terns spec.
153 Bridled Terns
4 Little Terns
6 Gull-billed Terns
52 White-winged Terns
92 Whiskered Terns
4 Common Terns
2 Greater Crested Terns

Swift(lets), swallows and martins:
30 Pacific Swifts
62 House Swifts
18 Barn Swallows

Passerines:
1 cuckoo spec.
56 Brown Shrikes
1 Blue Rock Thrush
2 Grey Wagtails

Checklist on eBird: https://ebird.org/checklist/S109518019
Count on Trektellen: https://trektellen.nl/count/view/3323/20220501

2 May was a similar day, with continued northerly winds, force 4 to 5, with some rain in the morning, but dry in the afternoon. I watched from 09h25 until 15h50.

Seabirds:
88 Red-necked Phalaropes
2 jaegers spec.
1 Brown Booby

Egrets and herons:
33 egrets spec.
5 Great Egrets
132 Eastern Cattle Egrets

Waders:
79 waders spec.
16 Eurasian Whimbrels
1 Sharp-tailed Sandpiper
2 Red-necked Stints

Terns:
32 terns spec.
48 Bridled Terns
1 Little Tern
2 Gull-billed Terns
55 White-winged Terns
34 Whiskered Terns
21 Common Terns

Swift(lets), swallows and martins:
13 Pacific Swifts
22 House Swifts
2 Barn Swallows

Passerines:
2 Eastern Yellow Wagtails

1 Ruddy Turnstone was present on the rocks and would continue to be seen on the next days.

Checklist on eBird: https://ebird.org/checklist/S109518616
Count on Trektellen: https://trektellen.nl/count/view/3323/20220502

3 May was the start of the non-stop part of this survey. Although I seawatched for only a half day, with a change in weather there was also an obvious change in the number of birds. Winds were blowing from the northeast with force 5, but turned to the east with force 4. It was partly sunny, partly cloudy and temperatures were rising as well. I watched from 11h40 until 17h50.

Seabirds:
2 Red-necked Phalaropes
1 Short-tailed Shearwater
4 Parasitic Jaegers

Egrets and herons:
11 egrets spec.
3 Eastern Cattle Egrets

Waders:
3 waders spec.
2 Eurasian Whimbrels

Terns:
15 terns spec.
115 Bridled Terns
10 Little Terns
151 White-winged Terns
36 Whiskered Terns
1 Black-naped Tern
292 Common Terns
11 Greater Crested Terns

Swift(lets), swallows and martins:
1 House Swifts
4 Barn Swallows

Passerines:
1 Grey Wagtail
3 Eastern Yellow Wagtails

Checklist on eBird: https://ebird.org/checklist/S109520005
Count on Trektellen: https://trektellen.nl/count/view/3323/20220503

The next day, 4 May, was finally a full day and I saw about double as much (1,180) birds as on the previous day (666), with migration in full swing. No more rain, with partly sunny, partly cloudy skies and winds blowing from the east with force 4 to 5. I started at 05h45 and watched until 18h00.

Seabirds:
116 Red-necked Phalaropes
5 Parasitic Jaegers
9 Short-tailed Shearwaters
1 Brown Booby

Egrets and herons:
8 egrets spec.
2 Great Egrets
2 Intermediate Egrets
16 Little Egrets
28 Eastern Cattle Egrets
1 Chinese Pond Heron
1 Striated Heron

Raptors:
1 Western Osprey
1 Peregrine Falcon

Waders:
5 waders spec.
1 sand plover spec.
1 Eurasian Whimbrel
8 Red-necked Stints
26 Terek Sandpipers
10 Oriental Pratincoles

Terns:
39 terns spec.
88 Bridled Terns
48 Aleutian Terns
62 Little Terns
31 Gull-billed Terns
114 White-winged Terns
49 Whiskered Terns
6 Black-naped Terns
447 Common Terns
28 Greater Crested Terns

Swift(lets), swallows and martins:
22 Barn Swallows

Passerines:
1 Chestnut Bulbul
1 Grey Wagtail
2 Eastern Yellow Wagtails

Checklist on eBird: https://ebird.org/checklist/S109521140
Count on Trektellen: https://trektellen.nl/count/view/3323/20220504

And 5 May was an even better day, with slightly more birds (1,354), high counts and good species. And actually, the weather was better, too: more sunshine and less wind, but still blowing from the east, with force 4. My watching hours were 05h45 until 17h40.

Seabirds:
220 Red-necked Phalaropes
10 Parasitic Jaegers
2 Streaked Shearwaters
11 Short-tailed Shearwaters
1 Brown Booby
1 Red-footed Booby

Egrets and herons:
10 egrets spec.
1 Great Egret
2 Little Egrets
14 Eastern Cattle Egrets

Raptors:
1 Western Osprey

Waders:
1 Pacific Golden Plover
6 Eurasian Whimbrels
1 Oriental Pratincole

Terns:
77 terns spec.
130 Bridled Terns
63 Aleutian Terns
159 Little Terns
1 Gull-billed Tern
77 White-winged Terns
29 Whiskered Terns
11 Roseate Terns
27 Black-naped Terns
456 Common Terns
19 Greater Crested Terns

Swift(lets), swallows and martins:
2 Pacific Swifts
22 Barn Swallows

Checklist on eBird: https://ebird.org/checklist/S109526582
Count on Trektellen: https://trektellen.nl/count/view/3323/20220505

And when you thought we’d seen it all on the previous days, 6 May proved yet another good day. Same weather, just a notch less wind (east, force 3). I seawatched from 05h45 until 17h30.

Seabirds:
309 Red-necked Phalarope
1 jaeger spec.
27 Parasitic Jaegers
1 storm petrel spec.
12 Streaked Shearwaters
10 Short-tailed Shearwaters
1 Masked Booby
1 Brown Booby

Egrets and herons:
4 egrets spec.
1 Great Egret
5 Eastern Cattle Egrets

Waders:
2 Oriental Pratincoles

Terns:
81 Bridled Terns
67 Aleutian Terns
92 Little Terns
179 White-winged Terns
8 Whiskered Terns
4 Roseate Terns
3 Black-naped terns
280 Common Terns
17 Greater Crested Terns

Checklist on eBird: https://ebird.org/checklist/S109526805
Count on Trektellen: https://trektellen.nl/count/view/3323/20220506

So that was it? Nope. Also the following day, 7 May, turned out to be good, with more than 2,000 birds counted. Similar weather, just the wind had turned northeast, still force 3. I seawatched from 05h40 until 17h30.

Seabirds:
821 Red-necked Phalaropes
16 Parasitic Jaegers
3 Streaked Shearwaters
18 Short-tailed Shearwaters

Egrets and herons:
9 Little Egrets
14 Eastern Cattle Egrets

Waders:
21 waders spec.

Terns:
96 terns spec.
40 Bridled Terns
312 Aleutian Terns
35 Little Terns
2 Gull-billed Terns
336 White-winged Terns
2 Roseate Terns
6 Black-naped Terns
258 Common Terns
16 Greater Crested Terns

Swift(lets), swallows and martins:
2 Barn Swallows

Passerines:
2 Grey Wagtails
1 Eastern Yellow Wagtail

Checklist on eBird: https://ebird.org/checklist/S109526904
Count on Trektellen: https://trektellen.nl/count/view/3323/20220507

And even on the last day, 8 May, when I only watched from 05h30 to 13h30, no less than 1,536 migrants were counted. The weather turned cloudier and the eastern winds increased to force 5. With very clear views and excellent lighting, fewer seabirds were seen, though.

Seabirds:
525 Red-necked Phalaropes
3 Parasitic Jaegers
3 Short-tailed Shearwaters

Egrets and herons:
11 egrets spec.
6 Eastern Cattle Egrets

Waders:
12 waders spec.
3 Oriental Pratincoles

Terns:
40 terns spec.
248 Bridled Terns
254 Aleutian Terns
18 Little Terns
7 Gull-billed Terns
205 White-winged Terns
14 Roseate Terns
7 Black-naped Terns
164 Common Terns
14 Greater Crested Terns

Swift(lets), swallows and martins:
6 Pacific Swifts

Checklist on eBird: https://ebird.org/checklist/S109527022
Count on Trektellen: https://trektellen.nl/count/view/3323/20220508

Remarks

This survey was the first in history during which full-time, whole day seawatching was performed from Nam Kok Tsui for several consecutive days in May. It is actually no surprise to me that this uncovered the great potential of the area (and, as you know, I’m sure I don’t see everything). Additionally, early May is clearly an excellent time (also no surprise), and there’s a fair chance that a full week of full-time seawatching is almost guaranteed to produce good stuff. Continuing heavy rains or daily thick mist are the two weather conditions that might prevent much of that, but most other weather should be fine. Not for every sort of species, but there should be something good on most days.

That’s the only and most important remark I want to make here.
Author: badesc    Time: 30/05/2022 14:37

15 May

15 May was another Sunday survey. The weather wasn’t that good, in the sense that it was rainy with limited visibility until noon. Still cloudy, but it turned dry in the afternoon. Winds were blowing from the east with force 6. Maybe good for seabirds on paper, but not so in reality. I watched from 09h25 until 15h25. Note that we generally mention only migrants here; on eBird and Trektellen individuals that were present are mentioned as well.

Seabirds:
25 Red-necked Phalaropes
1 Short-tailed Shearwater

Egrets and herons:
3 Chinese Pond Herons
2 Great Egrets
1 Little Egret

Waders:
6 waders spec.
1 Oriental Pratincole

Terns:
145 Bridled Terns
16 White-winged Terns
8 Greater Crested Terns
2 Roseate Terns
1 Aleutian Tern

Swift(lets), swallows and martins:
1 Pacific Swift
2 Barn Swallows

Passerines:
1 Brown Shrike

Checklist on eBird: https://ebird.org/checklist/S111058881
Count on Trektellen: https://trektellen.nl/count/view/3323/20220515

Remarks

No remarks for just one day, that wasn’t a full day anyway. We’ll discuss wind directions and force later in this thread. But it’s an example that rainy, windy days might not be that good.
Author: badesc    Time: 30/05/2022 14:41

17 to 21 May

So we planned yet another multi-day survey, with three full days and four mornings.

The day of my arrival on Po Toi, 17 May, I only watched from 11h25 until 17h40. First days of a survey, with the ferry which runs late, usually are of a slow start. It was mainly sunny with little cloud cover and still easterly winds, but only force 2 to 3, increasing to 4.

Seabirds:
23 Red-necked Phalaropes
1 Brown Booby

Egrets and herons:
6 egrets spec.
12 Eastern Cattle Egrets
3 Little Egrets

Terns:
1 tern spec.
148 Bridled Terns
53 White-winged Terns
6 Common Terns
3 Greater Crested Terns
2 Gull-billed Terns
2 Whiskered Terns
1 Black-naped Tern

Swift(lets), swallows and martins:
1 Barn Swallow

Checklist on eBird: https://ebird.org/checklist/S111144358
Count on Trektellen: https://trektellen.nl/count/view/3323/20220517

18 May was thus our first full day, from 05h30 until 17h00. Mainly cloudy, but winds had increased to force 5, but then decreased to 4 in the late afternoon.

Seabirds:
148 Red-necked Phalaropes
2 Parasitic Jaegers
6 Short-tailed Shearwaters

Egrets and herons:
2 egrets spec.
9 Eastern Cattle Egrets
5 Little Egrets
4 Great Egrets

Waders:
2 waders spec.
12 Oriental Pratincoles

Terns:
6 terns spec.
187 Bridled Terns
58 Common Terns
31 White-winged Terns
12 Greater Crested Terns
7 Whiskered Terns
3 Little Terns

Swift(lets), swallows and martins:
2 Pacific Swifts
18 Barn Swallows

Checklist on eBird: https://ebird.org/checklist/S111144566
Count on Trektellen: https://trektellen.nl/count/view/3323/20220518

Still a windy start on 19 May, with force 5 from the east in the morning, however it decreased to force 4. It was mainly sunny and I seawatched from 05h30 until 17h00.

Seabirds:
108 Red-necked Phalaropes
3 Parasitic Jaegers
5 Short-tailed Shearwaters

Egrets and herons:
1 egret spec.
12 Eastern Cattle Egrets

Raptors:
1 falcon spec.

Terns:
14 terns spec.
118 Bridled Terns
93 White-winged Terns
51 Common Terns
31 Aleutian Terns
30 Whiskered Terns
12 Little Terns
11 Greater Crested Terns
6 Roseate Terns
1 Black-naped Tern
1 Gull-billed Tern

Swift(lets), swallows and martins:
15 Barn Swallows
1 Pacific Swift

Checklist on eBird: https://ebird.org/checklist/S111144802
Count on Trektellen: https://trektellen.nl/count/view/3323/20220519

20 May saw a change in weather: warm and sunny, with force 3 from the northeast before noon turning to force 1 to 2 winds from the southeast in the afternoon. I was for sure and by far the best day for seabirds of this survey, and we watched from 05h30 until 17h30.

Seabirds:
411 Red-necked Phalaropes
2 Parasitic Jaegers
16 Short-tailed Shearwaters
2 Streaked Shearwaters
1 Bulwer’s Petrel (+1 very likely, but a bit far)
1 booby spec.
1 Red-footed Booby

Egrets and herons:
2 Great Egrets

Swans:
1 Black Swan

Terns:
4 terns spec.
171 Common Terns
91 Bridled Terns
12 Greater Crested Terns
9 Little Terns
9 White-winged Terns
6 Aleutian Terns
6 Gull-billed Terns
4 Whiskered Terns
2 Roseate Terns

Checklist on eBird: https://ebird.org/checklist/S111144967
Count on Trektellen: https://trektellen.nl/count/view/3323/20220520

And our last day, 21 May, which was also our last day for spring 2022, wasn’t too bad for seabirds either. Even though warm and sunny weather with force 1 winds from the southwest might not be appealing in theory. But theory and practice don’t always match.

Seabirds:
242 Red-necked Phalaropes
7 Short-tailed Shearwaters
5 Streaked Shearwaters
1 Brown Booby

Egrets and herons:
2 egrets spec.
1 Great Egret

Terns:
1 tern spec.
59 White-winged Terns
49 Common Terns
27 Bridled Terns
18 Greater Crested Terns
5 Little Terns
2 Gull-billed Terns
1 Aleutian Tern
1 Black-naped Tern
1 Roseate Tern

Swift(lets), swallows and martins:
4 Barn Swallows

Checklist on eBird: https://ebird.org/checklist/S111145175
Count on Trektellen: https://trektellen.nl/count/view/3323/20220521

Remarks

Clearly, the overall numbers of terns were lower in the third week of May than what we counted in the first week. But surveys should be done over a number of years again (like 2006-2012) to get a fuller picture.

We encountered satisfying passage of seabirds again. It is a topic to still further investigate and to then elaborate on in our 2022 year in review, but I’m more than happy without strong or fresh winds, as calm weather produced actually more seabirds than with strong onshore winds.
There weren’t any new high counts during this week and most bird species and numbers were probably rather normal.

A video on YouTube, showing some species we recorded, can be viewed here: https://youtu.be/nImkoWQTZcI

[ Last edited by badesc at 30/05/2022 14:44 ]
Author: badesc    Time: 30/05/2022 14:51

May 2022

Let’s wrap-up May, using data from Trektellen. There were 3 surveys on 14 days, with 7 full days and 7 half/partial days; the latter included 3 days when we returned by ferry on the same day. This results in total observation time of a decent 128 hours and 55 minutes. And that is an absolute record for any month since we started our surveys last year (or actually in the history of Hong Kong). It’s also the first and only month with over 100 hours.

It was a good month as well, but I feel April is actually as good, and even better for high numbers of certain species, such as Greater Crested Tern, Gull-billed Tern, Little Tern, Parasitic Jaeger and maybe others. The only reason May looks better than April this year, is that we couldn’t perform enough seawatching last month. As mentioned earlier, total observation hours for April were less than 68 hours, substantially less than in May, and we had only one full day in April. That month was vastly under-watched, so there’s work to do in the next April.

On the one hand, we counted 42 migrant species (that’s without the specs., like ‘tern spec.’) this May. That’s actually less than the 46 last April, again indicating how good April should be. But on the other hand, we counted 11,924 migrating individuals, a lot more than in April (4,314). Only when we watch for an equal number of full days and hours should April and May be better comparable, in this respect. But let’s just say that almost 12,000 birds is not bad. And of course, it would be ideal if we’d had a team of 2 or 3 seawatchers, some with scopes, some with bins, and we’d see even a lot more, for sure...

These are some interesting totals, with the highest count on a day for May between brackets (if it is worthy mentionable).

1 storm petrel spec., likely Swinhoe’s
24 Streaked Shearwaters
88 Short-tailed Shearwaters (18 on 7 May)
1 Bulwer’s Petrel, plus 1 very likely Bulwer’s
287 Eastern Cattle Egrets (132 on 2 May)
1 Masked Booby
2 Red-footed Boobies
7 Brown Boobies
3,097 Red-necked Phalaropes (821 on 7 May)
60 Gull-billed Terns
171 Greater Crested Terns
409 Little Terns (159 on 5 May)
783 Aleutian Terns (312 on 7 May)
1,619 Bridled Terns (248 on 8 May)*
42 Roseate Terns
2,256 Common Terns (456 on 5 May)
291 Whiskered Terns (92 on 1 May)
1,430 White-winged Terns (336 on 7 May)
73 Parasitic Jaegers (27 on 6 May)
50 Pacific Swifts (30 on 1 May)
85 House Swifts (62 on 1 May)
57 Brown Shrikes (56 on 1 May)

* Bridled Tern is a bit harder to count, as it is also a local species and these birds might use the same route to go feeding as migrants do. We counted only the ones that flew to the northeast and there’s a good chance that they are indeed mostly migrating birds.

I believe we did not encounter real rarities or true vagrants, except for the Masked Booby. I believe all other scarce species can be seen every year, likely more than once. It all depends how often and how long one is seawatching.

You can check out all the numbers at https://trektellen.nl/site/totals/3323/2022/5/1.

You may have noticed that I now sometimes use the flight direction NW (northwest). Why have I introduced this and what is the difference between W (west) and how sure am I these birds indeed fly to the NW? I’ll explain, but you can skip this part if you want.

This spring, I noticed that all egrets come from a southerly direction. Actually, none fly from the west to the northeast, like most other migrants do. And egrets also do not fly over land, i.e. straight over Po Toi. At one point, and well in advance of reaching land, they make a bend. Either they fly to the northeast, to the left of me, or they fly to the right of me, in the direction of Mat Chau. I believe they are all northbound birds: they don’t take the southbound route, which goes towards the west, as seen from Po Toi. Hence, NW means birds flying northbound, but via a route to the north of Po Toi.
N (north) have been northbound birds, mostly passerines and swifts, swallows, that fly over land, over Po Toi. NE (northeast) are birds that fly through the Lema Channel.

Apart from egrets, I also noted that quite a few Whiskered Terns and to a lesser extent White-winged Terns take this northwest route that some egrets follow. They clearly don’t fly to the west, but they do come from the east or southeast when I first see them. And the same is true for some Red-necked Phalaropes.

This could indicate that, in particular egrets and some terns, are not exclusively coastal migrants, but birds that come from Southeast Asia and migrate over sea, until they reach the southern coast of China. Species like Whiskered Tern and White-winged Tern might then as well fly over land to reach their northerly breeding grounds. Coastal breeders, like Greater Crested Terns and Aleutian Tern, are not seen coming from the south, but from the west and then flying to the northeast off Po Toi, which also makes sense. Common Tern is a bit of a strange fellow, as it does breed inland and could well migrate further over land. Yet, this species going northwest is rather exceptional and most choose the northeast.

Anyway, Hong Kong waters is actually a quite complex area for both seabirds and migrants. It’s not just a straight coastline. I’m not sure that birds that fly northwest will continue to do so when I lose sight of them. It’s actually more likely they either turn north or northeast to follow their journey.
So we see that not all birds follow the same route. An important point to stress is that we do learn more as time goes by and we discover new things. And thus, there’s obviously still room to finetune what we believe is the direction in which different birds fly.
Author: badesc    Time: 30/05/2022 14:56

Summary of spring 2022

This is an overview of all (migrating) seabirds and all (migrating) terns and gulls seen during the spring (i.e. March, April and May) of 2022. Below are the totals for the whole season.





Note that I’ve adjusted the total count for Streaked Shearwater, as the 155 birds counted on 20 March might all still have been around on 21st, so they are subtracted from the count to limit the chance of a double count. Same for the Flesh-footed Shearwater, which was the same bird on two consecutive days.

Let’s go over the most noticeable species/numbers, with some additional comments.

(1) After more than 200 Streaked Shearwaters last February, 743 were counted in spring.
First, this should be the best year ever – and by far – for this species in Hong Kong. Doing regular surveys, including full days and having watched well over 400 hours this year, seem obvious reasons for the increase. But there could well be other reasons, as over a hundred were seen from the ferry by birders this year, and that had never happened before either.
Second, February and especially March have been the best months for this species, very obviously, as this chart from Trektellen shows (counts for both 2021 and 2022).



(2) 109 Short-tailed Shearwaters were counted, maybe/likely the best spring ever for Hong Kong as well. But there were not much surprises here. It is known that most pass-by in May and we indeed saw the highest numbers (16 and 18) on days in May.
It’s a bird that can fly-by at any moment of the day, so it was not a surprise that the 18 on 7 May, during one of our full-time sessions, was a new high count for Hong Kong.
It seems that most pass-by on less windy days. Days with wind force 4 to 6 produced the lowest numbers of this species.
Note that we saw them into July last year, so it suggests that it is a very regular migrant from April to July, with good numbers by the end of April and a peak throughout May, and less regular with small numbers in June and July. But this too, should be the subject for yet further research and finetuning.
Alas, Trektellen uses pre-defined periods and April to July is not one of them. The below chart covers April to June for both 2021 and 2022. Note that the gaps between the bars are very often because there are no data available then, as there was no seawatching done. It is likely there were Short-tailed Shearwaters passing-by on e.g. 22 to 24 May, but nobody was there. And they could be more regular in June than the charts suggest, as well. Hope we can fill these gaps over the years; still so much to discover…



(3) The Flesh-footed Shearwater was the first record for Hong Kong and has been documented earlier in this thread.

(4) One certain Bulwer’s Petrel in the afternoon of 20 May was followed by a very likely second one towards the evening. The latter is not mentioned in the list.
Note that Robert Hackel and I also saw a Bulwer’s Petrel, coming from the Lema Channel, from a boat on 29 April. An interesting fact is that the weather on 29 April and 20 May was rather similar: light winds, calm sea, warm and sunny and the birds were both seen in the afternoon. Of course, this can be a coincidence. The main point that I take away from this, is that I’m happy to go seawatching in spring on warm, sunny days with little wind.
Both records, and the ones seen last autumn, further indicate that this is an annual visitor to Hong Kong waters. There is not enough data to conclude if there are particular peaks in the year (but likely mainly in spring and in autumn), but broadly speaking, April to October is presumably a period in which they can be seen.

(5) The one storm petrel could alas not be identified to species. It should be Swinhoe’s, but some other species cannot safely be excluded, as the bird was not seen in flight. Nonetheless, it is interesting data, which may indicate that Swinhoe’s is less likely to be seen in spring and (much?) more likely in late summer/autumn (August to October). I mean that the absence, apart from this possible bird, is as much indicative as its presence would have been. We hope we can add some more data of this species in the coming autumn to get a better understanding of the peak season in Hong Kong for this seabird.

(6) No less than 12 Brown Boobies were seen this spring. Note that there are 13 records of this species in all the years prior to 2021. Usually one per year, with the exception of 2009 (3). This species was also not recorded in 2011 to 2016.
We encountered two together on 29 March and 6 May. I know of at least one certain sighting from a boat this spring by Martin Williams and at least one possible one from the ferry.
Additionally, we saw 3 in total in the summer of last year. But it looks likely to be a regular spring migrant, though mostly singles on a given day.

(7) The Masked Booby on 6 May is the second record for Hong Kong, if accepted. The previous one, an immature, was also seen from Po Toi, on 18 March 2008.

(8) Red-necked Phalaropes were seen on all except 3 days (6 and 13 March and 15 April). High counts of 601 on 30 March and 821 on 7 May are noteworthy. Certainly the high count in May is, based on what we know from the past, rather exceptional, as high numbers usually occur earlier in spring.

(9) 200 Parasitic Jaegers this spring is perhaps yet another historically high count for any year in Hong Kong. A record high number of 43 was seen on 25 April and discussed in a previous post.

(10) We encountered 28 Ancient Murrelets in spring, including a record high count for Hong Kong of 14 on 13 March. We actually saw 50 in January and February, making it more of a winter visitor/migrant (but none were seen in December 2021) than a spring visitor/migrant, based on our data so far.

(11) 827 Heuglin’s Gulls were counted in spring, and 997 in both the 2022 first winter period and spring. March is clearly the top month for this (sub)species and much fewer were seen in April, although we didn’t perform that many surveys during that month, as you know. Our highest count this spring was 267 on 30 March.

(12) As can be seen from the above tables, terns were the most common birds this spring. That was also the case last summer (August) and autumn (September). From high to low, the most numerous this spring were Common Tern (2,917), Bridled Tern (1,665), White-winged Tern (1,455) and Aleutian Tern (1,387). But 898 Greater Crested Terns and 748 Little Terns are not bad either.
The highest numbers, of mainly Common Tern, were noted in early May. The best days for this species were 4 and 5 May with resp. 447 and 456. These were the highest counts for Hong Kong this century. Although it would always be good to double check in the future, we believe these are normal numbers for this species in spring.
We thought we could perhaps count a record high number of Greater Crested Terns, but due to a lack of full days in April, this goal was not reached. But 127 on 25 April (precisely the only full day of the month) and 114 on 30 March were noteless the second and third highest count for Hong Kong; the record of 165 was on 10 September 2021.
A much anticipated species we were on the lookout for, Chinese Crested Tern, was not seen. That is not so unusual, as it is of course a very rare bird anywhere. I saw some crested terns in the second half of March that I’d love to see a bit closer during a future survey. I believe Chinese Crested is likely to pass Hong Kong, but perhaps it will only be a few at most. Checking every crested tern is what we must continue to do…

[ Last edited by badesc at 9/07/2022 10:22 ]

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Author: wgeoff    Time: 30/05/2022 16:11

I would like to thank and congratulate Bart for the fantastic effort he has put into these seawatch surveys from Po Toi.

Without going into the details of his records, which will take some time to absorb, I know we have learnt a great deal about seabirds in HK and local waters over the past year. It has been a privilege to learn so much that we previously did not know or only guessed.

Congratulations Bart, please keep it going. I hope you can find someone to join you on these sea watches to share and even increase the numbers and species seen.

Geoff Welch

[ Last edited by wgeoff at 30/05/2022 16:15 ]
Author: wcaptain    Time: 30/05/2022 16:31

Hi Bart

THX for your painstaking and hard works on seabirds

About your data of streaked shearwaters and our sightings in recent oil rig trips (very common in Sept but uncommon in May), it is very likely that the Streaked Shearwater is a regular winter visitor to the northern South China Sea. My speculation is that it arrives in Sept and stays off shore. It becomes more "on shore" during winter monoons, in particular in March as your observations shown. It departs and migrates back to the breeding grounds (The East Sea?) in April

About the regular signting of Brown Bobby in May, maybe some young guys wander around this area, or this area falls within feeding range of adult birds that nesting in nearby areas (Xi sha!?) during the late breeding season.

Anyway, just my thoughts .....



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