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Subject: Po Toi Seawatch Summer 2022 [Print This Page]

Author: badesc Time: 20/06/2022 16:26 Subject: Po Toi Seawatch Summer 2022

After a good spring, and mainly a good month of May, and with the knowledge that summer is calmer than spring, I decided to slow down a bit. It probably won’t be for long, as the autumn migration starts in August. And I might try to go during a July typhoon as well.

19 June

June isn’t a month with zero migrants, as we’ve also experienced last year (https://www.hkbws.org.hk/BBS/vie ... &extra=page%3D1). So I did a Sunday seawatch survey to see if anything good would still pass. There had been southerly winds for quite some time, bringing cloudy and rainy weather to Hong Kong. On 19 June it was also mostly cloudy, with southerly winds, force 4 to 5.

Seabirds:
1 juvenile Lesser Frigatebird present

Terns:
1 tern spec.
2 Little Terns
1 Caspian Tern
2 Common Terns
5 Greater Crested Terns

Checklist on eBird: https://ebird.org/checklist/S113324594
Count on Trektellen: https://www.trektellen.nl/count/view/3323/20220619

Remarks

That was it and there’s not much to remark about. But we did not encounter any Little or Caspian Terns in June last year, so at least this short survey has provided some new data.

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Author: wcaptain Time: 20/06/2022 16:50

Author: badesc Time: 11/07/2022 16:28

30 June

We’ve seawatched on the last day of this month, as part of my very first dedicated storm seawatch survey, with storm signal T8 being in force at some time during the survey. The storm was ‘Tropical Cyclone Chaba’, which moved south of Hong Kong and from east to west. The prediction for Friday (1 July) looked promising on Windy:

I could start seawatching on 30 June at 12h00 and until 17h45. Winds were blowing from the northeast, with force 4 to 5. Furthermore, the weather was partly cloudy and dry, partly rainy with some squally showers.

Prepared to be dressed for rain...

...which soon appeared on the horizon

Seabirds:
1 Brown Booby
1 Parasitic Jaeger

Waders:
3 Tringa spec.

Terns:
11 Greater Crested Terns
5 White-winged Terns
4 Whiskered Terns

Swift(lets), swallows and martins:
1 Pacific Swift, present

Checklist on eBird: https://ebird.org/checklist/S114569743
Count on Trektellen: https://www.trektellen.nl/count/view/3323/20220630

Remarks

Let’s safe the remarks for the whole storm seawatch survey, which ended on 5 July (see below). But the one point for 30 June that I want to make here, is 11 Greater Crested Terns. Last year the highest count was 13, but on 9 June. On 26 June, we counted only 5. So, 11 was not a bad count for the end of this summer month.

[ Last edited by badesc at 11/07/2022 16:30 ]

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Author: badesc Time: 13/07/2022 15:00

June 2022

Let’s wrap-up June, using data from Trektellen. There were only 2 surveys, one Sunday survey and one half day. Total observation time was just 13 hours and 30 minutes.

As a result, there is very little data to comment on. Yet, Brown Booby (1 seen), Parasitic Jaeger (1), Caspian Tern (1), Little Tern (2) and Common Tern (2) are not really common birds in this month in Hong Kong.

Author: badesc Time: 13/07/2022 15:48

1 to 5 July

The majority of the time spent on seawatching during Chaba was thus done in the first five days of July. 1 July was a tough day weather-wise (but more on that in the remarks). The storm signal was raised to T3. Before noon the weather was okay, dry and partly sunny, partly cloudy. All birds were seen during this time. Winds were blowing from the northeast with force 7 to 8. After noon, there were squally showers with very limited visibility and no passing (sea)birds were seen. I watched from 05h50 until 14h45.

Seabirds:
1 juv. Sooty Tern

Gulls:
1 Black-tailed Gull

Terns:
4 Greater Crested Tern

Swift(lets), swallows and martins:
3 Pacific Swifts, plus 1 present

Checklist on eBird: https://ebird.org/checklist/S114570109
Count on Trektellen: https://www.trektellen.nl/count/view/3323/20220701

On 2 July, storm signal T8 was in force. It was lowered to T3 in late afternoon. I watched all day, from 06h00 to 17h50. This was the day when Chaba was close and we should get the full impact of it – including birds. The weather was remarkably similar to the previous day, being dry in the first few hours, and rainy with squally showers afterwards. Luckily, there were also a few relatively dry periods, during which birds were usually seen. But very few, and apart from the local terns, (sea)birds. Actually disappointing. Winds were blowing fiercely, with force 8; from east turning to southeast. On Windy, it looked great:

Seabirds:
2 Streaked Shearwaters
1 storm petrel spec.
1 Bulwer’s Petrel
1 Brown Booby

Checklist on eBird: https://ebird.org/checklist/S114570442
Count on Trektellen: https://www.trektellen.nl/count/view/3323/20220702

On 3 July, the worst of the storm had passed, but bird-wise it was by far the best day of this survey. Storm signal T3 was in force until around 14h00 and winds calmed down a bit to force 6, coming from the south. No more heavy rain but cloudy and dry, even with a bit of sunshine now and then. I seawatched from 06h00 until 17h00.

Seabirds:
1 Short-tailed Shearwater
1 Bulwer’s Petrel
5 Red-footed Boobies
2 Parasitic Jaegers
3 juv. Sooty Terns

Terns:
9 Greater Crested Terns

Checklist on eBird: https://ebird.org/checklist/S114570776
Count on Trektellen: https://www.trektellen.nl/count/view/3323/20220703

By 4 July, the storm signals were dropped. Winds were force 6, decreasing to force 5 in the afternoon, and coming from the south to southwest. Weather was good, as it was cloudy but dry. Jaegers, Sooty Tern and boobies passed-by during a very short 15 minutes in the morning; that was it (the phalaropes appeared in the afternoon). I started seawatching at 06h00 and stopped at 16h00.

Seabirds:
2 Red-footed Boobies
2 Parasitic Jaegers
5 Red-necked Phalaropes
1 juv. Sooty Tern

Terns:
12 Greater Crested Terns

Checklist on eBird: https://ebird.org/checklist/S114578572
Count on Trektellen: https://www.trektellen.nl/count/view/3323/20220704

And the last day, 5 July, was another very quiet day. Again cloudy and dry, with southwest winds force 5, decreasing to 4. I watched from 06h00 until 12h00.

Seabirds:
1 Brown Booby

Terns:
3 Greater Crested Terns
1 Common Tern

Checklist on eBird: https://ebird.org/checklist/S114578787
Count on Trektellen: https://www.trektellen.nl/count/view/3323/20220705

Remarks

We’ll discuss the full storm seawatch survey, from 30 June until 5 July, here.

It certainly was quality, rather than quantity, and there were meagre days. But the full list of (sea)birds was actually not bad, with even some remarkable facts:

2 Streaked Shearwaters
1 Short-tailed Shearwater – A not unusual summer bird, like we saw last year (7 in July).
2 Bulwer’s Petrels – Classic, storm-driven individuals during non-migrating times, I reckon.
1 storm petrel spec. – Idem.
7 Red-footed Boobies – 5 on one day was a new record high count for Hong Kong; single birds from all previous records. During the storm, 3 together were seen off Green Island by other observers, of which at least one (based on shared photos) was in a plumage that was not seen on any of the ones off Po Toi.
3 Brown Boobies – One of them was feeding actively and that's the first time I have seen this species doing that in Hong Kong. 15 BB’s have now been counted from Po Toi this year.
5 Red-necked Phalaropes
5 Parasitic Jaegers – The not unusual summer birds, like we saw last year (9 in July).
1 Black-tailed Gull – 5th summer record for Hong Kong; I’d say this was the most unusual sighting for this survey. This bird should not be here.
5 Sooty Terns – 3 on one day was a new record high count for Hong Kong; the previous peak count was two on 3 August 2016.
39 Greater Crested Terns – Perhaps not a bad count for mid-summer (11 on 30 June and 28 on 1 - 5 July). It seems that they are regular, albeit in small numbers, throughout summer, and numbers increased considerably last year in August (which we count as a summer month in Hong Kong, but is actually an autumn month for migrating birds).

I've made this video of a Red-footed and a Brown Booby: https://youtu.be/pp7QJQV9I-o

We’ve wondered what could be seen shortly before, during and shortly after a full (T8) storm on Po Toi. Storm seawatching from Cape D’Aguilar has been done regularly in the past. But when you look at a map, you’d agree that Po Toi should be even more promising. This first dedicated, full-time storm seawatch survey illustrates the potential of the waters off Nam Kok Tsui. I reckon a similar storm in August or September might be even much better. There is a good change we might find out in the coming months or years.

One of the main challenges is of course getting to the island before the storm, as ferries will not run as soon as T3 is in force. And then reserve a week or so, because you never know for sure how the storm will evolve and it could take longer than planned to get off the island again.

Previously, my main concern was finding a safe and suitable seawatching spot. A usual spot on the rocks is generally out of the question during a typhoon (T8). It is not only outright dangerous for yourself, but you risk harm to or even loss of your equipment. The steady waves and salt sprays are not the biggest tread, but the unexpected large waves that can catch you by surprise are.

The lighthouse is an option, but I feel it is much too high. For very strong northeast to southeast winds, I did find a suitable alternative near the rocks. Very well protected from even the largest waves, stormy winds, any salt water, and away from the shoreline and on a flat surface.

It is marked with the green circle on this map:

And this is how it looks like, facing the sea:

Is it perfect? No, it’s not. But during a typhoon, you’ll always have to give in on something. You indeed lose about 100 m. to the southeast and almost 200 m. to the southwest. And a part of the rocks obstructs the view. But there is a very large gap to the left of that, where you can see the Lema Channel. And to the right, you can view all of the Hong Kong southern waters. The height is very good. Your tripod and scope are stable. And it’s very safe. Only if winds would turn to the south, you can’t avoid them, unless you give up views of the Lema Channel. (Note: when winds decreased to force 6, coming from the south, I headed back to the rocks and sat on the northwest side, where I could hide from direct winds and waves. I had to regularly bear very fine salt sprays, though.)

Talking about winds, this survey let me experience strong southerly winds. Much more than any other wind I have encountered, these winds truly push seabirds, flying from west to northeast, towards the Nam Kok Tsui peninsula. I could see Red-footed Boobies far away, drifting closer and closer until they passed-by at a range (500 m. or perhaps even closer) which I never encountered before. Also, Short-tailed Shearwater, Parasitic Jaegers, Sooty Terns and Greater Crested Terns passed-by unusually close. The Bulwer’s Petrels were one of the few seabirds that were not pushed towards the peninsula.

However, I struggled to get good photos, even tough there was plenty of opportunity. A reason was that I often sat behind a rock and birds would disappear behind that a bit too soon to get them on camera. And another reason is that my camera was almost all the time in my backpack, covered with a backpack cover and put in a plastic bag, as the lens is not waterproof. There was always a chance for rain or salt sprays. Unpacking it would simply take too much time. Another point to improve upon, as a ‘LensCoat RainCoat’ (https://www.lenscoat.com/raincoats-raincaps-c-34.html) should come to the rescue next time.

Speaking of rain. Lengthy (two to three hours) of almost continues heavy showers with squalls is part of every typhoon. I’ve learned that there is not much choice than to just sit through them. There is nothing to see, as visibility becomes very limited (<500 m.). Birds might appear ones the rain stops – and you have to be there at that moment –, and some less rainy periods in between can produce something as well. But I’d say: no pain, no gain, and no typhoon without rain. ;-)

We learned a lot, made some mistakes and did some things wrong, so there will be plenty to improve on during our next storm seawatch survey.

[ Last edited by badesc at 21/07/2022 16:10 ]

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Author: wcaptain Time: 14/07/2022 11:52

Author: John Holmes Time: 15/07/2022 09:02 Subject: Po Toi Typhoon birding

Great stuff, Bart ! I’m really looking forward to the next adventure.

But be careful out there.

Author: badesc Time: 3/08/2022 17:27

July 2022

Let’s wrap-up July, using data from Trektellen. There was just one survey during this month, from 1 to 5 (although it actually started on 30 June), 4 full days and one half day, resulting in 47 hours and 45 minutes of seawatching. Only 16 species + storm petrel spec. were seen. But as I wrote, it was quality over quantity.

With just this one survey, I refer to the above report and remarks, as what there is to say is mentioned there.

[ Last edited by badesc at 3/08/2022 20:54 ]

Author: badesc Time: 17/08/2022 14:44

7 to 11 August

As there was a forecast for another storm developing in the South China Sea, I planned another seawatching survey to seawatch before, during and after the storm. On a practical note, it is basically compulsory to do it this way, as there will be no ferry once the storm comes closer and you’ll completely miss it if you wait for that.

I did share my opinion with some friends that a storm should be practicality a guarantee for bringing seabirds of interest to Hong Kong waters, so this was yet another test (and there should – and hopefully will be – more tests) to find out if that expectation is correct.

So I started well before the storm was supposed to come closest and went seawatching on Sunday 7 August. Winds were blowing from the northeast with force 4, turning to east with force 5, and it was quite hot and mainly sunny. I watched from 14h15 until 18h00.

Terns:
45 terns spec.
14 Greater Crested Terns
21 Bridled Terns
23 Common Terns

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

Checklist on eBird: https://ebird.org/checklist/S116818493
Count on Trektellen: https://www.trektellen.nl/count/view/3323/20220807

Although still no stormy weather on 8 August, a few thunderstorms appeared on an otherwise cloudy day with sunny periods. Winds were still blowing from the east with force 4 to 5. My seawatching hours were from 06h00 to 17h15.

Egrets and herons:
6 Eastern Cattle Egrets

Terns:
298 terns spec.
50 Greater Crested Terns
144 Bridled Terns
149 Common Terns

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

Checklist on eBird: https://ebird.org/checklist/S116818607
Count on Trektellen: https://www.trektellen.nl/count/view/3323/20220808

On 9 August the Hong Kong Observatory at 11h25 raised its Tropical Cyclone Warning Signal to T3, which means “strong wind” (“gale or storm” is actually T8). N.B.: the ferry arrived that day, with the warning signal T1 in force, but left at a quarter past twelve, instead of 15h30, because of T3. On the watch point, it was cloudy, rainy, with squally showers, but also with regular dry periods. Of course, I sat away from the rocks, at the alternative watch point as shown in this post http://www.hkbws.org.hk/BBS/view ... mp;page=1#pid88183. Winds were still blowing from the east, but now with force 7. I watched from 06h00 until 16h30.

Waders:
1 Eurasian Whimbrel

Terns:
14 terns spec.
5 Greater Crested Terns
31 Bridled Terns

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

Checklist on eBird: https://ebird.org/checklist/S116818683
Count on Trektellen: https://www.trektellen.nl/count/view/3323/20220809

The warning signal T3 was in force during the next day, 10 August, until shortly after 18h00. Winds blew from the east to the southeast with force 7 and gusts up to force 8. Again cloudy, rainy and a few squally thunderstorms, but also regular long dry periods and attempts to some sunshine. The storm had a name by now: Tropical Storm Mulan. Welcome, Mulan! Alas, it turned out to be a long (from 06h00 until 16h30) and very boring day with hardly any migrants and zero seabirds…

Terns:
4 terns spec.
7 Greater Crested Terns
2 Bridled Terns

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

Checklist on eBird: https://ebird.org/checklist/S116818778
Count on Trektellen: https://www.trektellen.nl/count/view/3323/20220810

On 11 August the storm had passed and I was back on the rocks. I watched from 06h00 until 13h30 during which it was mainly cloudy and dry, followed by some rain later. Wind force decreased to 4, coming from the east. Finally, the first (and only) seabird appeared…

Seabirds:
1 Red-footed Booby

Egrets and herons:
1 egret spec.

Waders:
1 wader spec.
2 Eurasian Whimbrels

Gulls:
1 Black-tailed Gull

Terns:
96 terns spec.
65 Greater Crested Terns
11 Little Terns
104 Bridled Terns
1 Roseate Tern
13 Common Terns

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

Checklist on eBird: https://ebird.org/checklist/S116818925
Count on Trektellen: https://www.trektellen.nl/count/view/3323/20220811

Remarks

For seabirds, this was the most disappointing survey so far, with results lower than the lowest expectations. The main point is of course: why didn’t we encounter more seabirds during a storm with (what I would suspect to be) suitable winds? My answer is that I don’t know. But I’m inclined to think that the most obvious reason would be that I simply didn’t see the seabirds that passed through. However, I feel it’s fair to say that most probably there weren’t lots of them.

We might elaborate on it in our 2022 review, but so far, I’m thinking of three weather types when it comes to seabirds in Hong Kong:

1/ Thick mist, with visibility of less than 1 km.
No seabirds to be seen, at least such circumstances have been non-productive so far.

2/ Shortly before, during or shortly after a storm (at least force 6 winds, preferably onshore, of which the best direction might be from the south).
Seabirds are practically guaranteed, and this has been the case during the 3 storm seawatch surveys that have been done in 2021 and 2022, and is confirmed by Geoff Welch’s experience.

3/ Every type of weather that is not one of the above.
Mainly unpredictable; it can produce any kind and any number of seabird(s), or none.

I must stress that this is a preliminary view and almost certainly prone to changes. We’re still learning and will be for quite some time.

Terns, on the other hand, are a bit easier to predict, probably. Most weather types, preferably clear and dry – at least no constant, heavy rain –, with winds no stronger than force 4 from any direction, are very likely to produce good numbers of terns during their peak passage, mainly April/May and August/September. However, and as mentioned here already, storms have produced record numbers in the past, but it seems that these birds then have been caught by surprise and that might be an exception rather than a rule. Interesting is that we saw a peak shortly before Tropical Storm Mulan, but very few during the storm, which further suggests that terns avoid stormy weather if they can. But this too, is prone for further research.

The 1st year Black-tailed Gull on 11 August was a new earliest date for Hong Kong, the previous one being 13 August.

As you know by now, I mention mainly migrants in these reports. And it has been written before that Bridled Tern is a tricky species to count, as local birds highly likely cross the Lema Channel too, to feed on the open sea. Yet, as our counts during this survey illustrate, when we count more Bridled Terns that appear to be migrants (flying straight and determined to the west in autumn or to the northeast in spring), we also count higher numbers of other tern species which are certain migrants. So, I believe our strategy to recognize migrants and separate them from locals, works rather well. But it may not be 100% accurate.

Same probably goes for Roseate Terns, of which we encountered the first southbound migrating bird this summer/autumn. Migrants generally behave quite different from local birds; we’ll continue to study it for the rest of the year and come back to it in the annual review. But I believe most migrant Black-naped, Roseate and Bridled Terns are distinguishable from locals.

What is much less easy, is distinguishing tern species of birds that fly far out. And their numbers can be very high. Last spring enabled me to again observe species like Common Tern and Aleutian Tern side-by-side, when they’re generally closer than in autumn. Far out, ID-ing them can be much harder (for me). But there are differences, like Aleutian being smaller, slightly slimmer, darker, and with a faster wingbeat. I do observe what are probably mixed groups of Common and Aleutian in autumn as I notice subtle difference of these birds. My approach so far has been to ID only the ones that are close enough to be sure or 90% sure. But that results in relatively few records, a minority of the total number of terns that pass. I could increase the count by putting a name on more birds, but the certainty would drop and the margin of error would be wider. We’ll see how this develops in the coming weeks.

Okay, that’s more than enough said. Looking forward, I mainly expect thousands of terns again in the coming weeks. And there’s a good chance of other (oceanic) stuff. But without a storm, that'll be mainly unpredictable...

[ Last edited by badesc at 17/08/2022 14:49 ]

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Author: badesc Time: 23/08/2022 16:18

20 to 21 August

This time of year, in most weather conditions, autumn migration off Po Toi really starts to take off, although it concerns mainly terns. The forecast was for two days of cloudy and to some degree rainy weather with southerly winds (20 and 21 August), followed by two days of calm and sunny weather (22 and 23). I thought it could be interesting to compare both very different weather types. Alas, the predictions were widely off the mark, and 20 and 21 were mostly sunny days already. That is on Po Toi, where the weather is generally better (less rain, shorter showers) than further north at Hong Kong Island or the New Territories.

Arriving with the ferry, I started seawatching on 20 August at 11h50 and until 17h30. Winds were blowing from the southeast with force 4 (maybe up to force 5 further off shore). It was partly sunny, partly cloudy, with just one (short) shower.

Seabirds:
1 Red-necked Phalarope

Egrets and herons:
7 egrets spec.
1 Little Egret
1 Chinese Pond Heron

Terns:
130 terns spec.; most probably Common Terns
27 Bridled Terns
18 Roseate Terns
31 Common Terns
34 Greater Crested Terns

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

Also a juvenile White-bellied Sea Eagle present.

Checklist on eBird: https://ebird.org/checklist/S117420732
Count on Trektellen: https://www.trektellen.nl/count/view/3323/20220820

So, instead of a forecasted very cloudy day on 21 August, we soon got a hot and sunny day. It was only cloudy in the early morning, with little rain. Winds were still blowing from the southeast, but with force 4, decreasing to force 3. My shirt was drenched in sweat and the breeze provided at least some cooling (or maybe I should say: preventing me from overheating…). Using an umbrella for the sun is not ideal, as I should have both hands free. And attaching it to my tripod only works with very light winds, or the whole thing becomes shaky. Anyway, no intend to complain, as it wasn’t a bad day, with 580 terns on the move. E.g., note that prior to 2021, the highest count ever of Greater Crested Terns on a day was 52. Now we consider that as a normal, not bad count.

Waders:
13 waders spec.
25 Eurasian Whimbrels

Terns:
278 terns spec.; most probably Common Terns
54 Bridled Terns
1 Aleutian Terns
7 Little Terns
5 Gull-billed Terns
178 Common Terns
57 Greater Crested Terns

Checklist on eBird: https://ebird.org/checklist/S117420802
Count on Trektellen: https://www.trektellen.nl/count/view/3323/20220821

Remarks

As you can see, I have now included which species the unidentified terns (“tern spec.”) most probably are. This way, we might get a better idea (but not a fact, as ID is only probable) of when certain species peak, although nothing substantial has been found so far; it’s too early to draw any meaningful conclusions yet, based on our own surveys.

I did notice, same as last autumn, that there is an obvious difference of the flight behaviour of migrating Common Terns and Roseate Terns. Remember that we’re not talking about close-by birds, but migrants at 1 to (mostly) 2 km out, and some even further, which makes identification often hard, especially in bad light. Yet, when they are not too far and lighting is good, plumage differences are seen, which makes ID-ing plausible and this experience then helps in ID-ing some of the more distance ones as well. Roseate Tern is a much whiter bird than Common, but Gull-billed Tern and Black-naped are the whitest terns. Roseate is structurally more elegant and elongated than Common. But I additionally found that the way they form groups is very different. Below is an illustration of what I mean: Common Terns pass-by in loose groups, with mostly some distance between individuals, flying substantially above the water. Roseate Terns fly low, close to the water (the horizontal line on the illustration) and they form a line formation, meaning mostly one after the other.

Roseate also flies very direct and undeterred, somewhat hurried. There is overlap with Common in this regard, but the latter is sometimes seen making turns and dive to the sea surface, while Roseate just keeps flying low.

Many tern species form different formations and fly at different heights. E.g., the largest species tend to fly the highest, namely Caspian Tern and Greater Crested Tern. The former also generally has the largest distance between individuals in a group. Low-flying species tend to be Roseate and to some extent White-winged Tern, mostly in groups in which birds fly in a line, closely following each other. Most other species fly at a height in between, but there is some overlap and it also depends on the direction and strength of the wind. Anyway, I found those differences often supportive for identifying tern species.

While I’m writing this, Tropical Cyclone Ma-on is on its way, almost straight to Hong Kong. It was first projected to move to Taiwan and with not enough preparation time left after I found out it would be heading for Hong Kong, I won’t be seawatching in the next couple of days. It could and should be a good storm, although the forecasting by the HKO of winds with force 11 offshore might be too much of a good thing. But we’ll never know. Maybe another time. I don’t think there will be a shortage of storms in the future.

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Author: badesc Time: 29/08/2022 09:58

August 2022

Let’s wrap-up August, using data from Trektellen. There were two surveys during this month, 3 full days and 4 half/partial days, resulting in 56 hours and 25 minutes of seawatching. That’s about 10 hours less than last year, with three surveys.

August 2022 confirmed what we found in August 2021: that autumn migrating kicks off. However, it is mostly of terns. With less observation hours, less terns were counted, but the results mirror those of last year. We counted a total of 1,917 terns. And exactly same as in 2021, Common Tern was most common (394), followed by Bridled Tern (383) and Greater Crested Tern (232). Equally, numbers of Gull-billed Tern (5) and Little Tern (18) were much lower. We did count only 1 Aleutian Tern this August, compared to 65 last year. But the majority were then seen at the end of the month, a period during which we did not do any surveys this year. I would have liked to check again for when most Roseate Terns pass through, as there was a peak last year on 16 August (81). But we had a peak count of only 18 this year, on 20 August. Note that there were no surveys on the same dates as last year, meaning it is possible that numbers of Roseate Tern peak during a very short period, likely from 15 to 20 August. But this is a case to further study in future years.

Overall, I’m glad with very similar counts for most tern species, as it strongly suggests that last years’ numbers were not exceptional. I guess the same will be true for September.

And there are more similar results between 2021 and the current year for August. We noticed the start of autumn migration of egrets and what seems to be the peak month in autumn for Eurasian Whimbrels. Also, in both this and last year single Red-footed Boobies and Black-tailed Gulls were seen in August. Jaegers were absent this year, but appeared near the end of the month last year, and we thus didn’t do any surveys in that period in 2022.

Author: badesc Time: 1/09/2022 13:34

Summary of summer 2022

This is an overview of all (migrating, except for the Lesser Frigatebird) seabirds and all (migrating) terns and gulls seen during the summer (i.e. June, July and August) of 2022. Below are the totals for the whole season.

There were only 14 survey-days (full or partial) in this summer, about half as much as last year (25). We mainly focussed on storms, of which there were a couple this summer. We managed to ‘catch’ just two of them, one in July and one in August (as described in detail above).

The summer is not a dead season off Po Toi. There’s still migration in June, storms in July (or any other summer month, actually) can bring seabirds in, and the autumn migration of mainly terns starts late July/early August. But of course, we don’t see an abundance of seabirds like in some other countries.

Just a few highlights or noticeable totals of this summer:

2 Bulwer’s Petrels
3 Brown Boobies
8 Red-footed Boobies
1 Lesser Frigatebird
5 Parasitic Jaegers
2 Black-tailed Gulls
5 Sooty Terns
397 Common Terns
276 Greater Crested Terns

Note that the list of seabirds and gulls & terns is rather similar in both 2021 (http://www.hkbws.org.hk/BBS/view ... amp;page=1#pid87021) and 2022. As we intentionally seawatched – when possible – on different dates in both summers, our surveys indicate a list of ‘usual suspects’ of seabird species during this season. Although I must stress that this is based on two years only of our own surveys, and it most probably needs to include a fruitful storm. These species are: Streaked Shearwater, Short-tailed Shearwater, Bulwer’s Petrel, Brown Booby, Red-footed Booby, Red-necked Phalarope, Lesser Frigatebird, Parasitic Jaeger, and Sooty Tern. An addition is likely Swinhoe’s Storm Petrel, but we only saw possible ones in both summers. However, as you know, a certain one was seen from a boat trip just outside Hong Kong waters on 29 August last year.

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Author: parrotkeen Time: 2/09/2022 12:53

Just a question, can other people go seawatching too? I would love it, provided it's safe.

Author: badesc Time: 3/09/2022 08:28

Quote:

Original posted by parrotkeen at 2/09/2022 12:53
Just a question, can other people go seawatching too? I would love it, provided it's safe.

Everybody can go seawatching on Po Toi. Locations are mentioned in the introduction of the 2021 review: http://www.hkbws.org.hk/BBS/view ... amp;page=1#pid87471

Author: parrotkeen Time: 13/10/2022 20:12 Subject: Rock safety

Also, how do we get on the rocks safely?

Author: badesc Time: 13/10/2022 21:55

Quote:

Original posted by parrotkeen at 13/10/2022 20:12
Also, how do we get on the rocks safely?

The answer to your question has already been given: http://www.hkbws.org.hk/BBS/view ... amp;page=1#pid88371

Author: parrotkeen Time: 14/10/2022 10:18 Subject: My bad

Oh, I didn't know that. Sorry for the inconvenience.

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