wgeoff

It’s that time of the year again. But this year, a quiz with a difference – one that requires some birding skills.

Below are 10 graphs showing the numbers and dates of my daily records of 10 regular Po Toi species during each of the years 2006 to 2011. The 10 species are five leaf warblers and five flycatchers.

You just need to name the species. Easy.

Here are the leaf warblers

1)

2)

3)

4)

5)


and here are the flycatchers

6)

7)

8)

9)

10)



Note, these are only my records so you can't cheat by finding your own records. Also, I don't always follow the Records Committee with species splits etc.

As usual, the Grand Prize is a free night on Po Toi in January (excluding meals at the restaurant) and the prestigious title ‘Bird Brain of Po Toi’.

Since these are all quite easy, I anticipate several fully correct entries so I have added one graph here from a different species altogether as a tie-breaker.

11)


Good luck, answers next week.

[ Last edited by wgeoff at 20/12/2011 18:06 ]

wgeoff

Good effort Gary.

If you try the flycatchers, you may win the prize.

wgeoff

That's correct.

Still one warbler (Gary's number three is wrong, the others are correct) and five flycatchers to go.

I'm off to China today so you're on your own until next Tuesday.

wgeoff

John's got five out of six correct but I'm not telling you which one is wrong.

Hartlaub's Touraco is an absurd guess - it's a resident on Po Toi.

wgeoff

I’m back from China, here are the answers and some graphs for other suggestions

1)        Arctic Warbler (not split).

2)        Pale-legged (and Sakhalin) Leaf Warbler

3)        Dusky Warbler. Gary had Pallas’s Leaf Warbler, it’s interesting to look at this and compare the three, Dusky (number 3), Pallas’s (below) and Yellow-browed (number 5). Here is Pallas’s Leaf Warbler



Fewer in numbers than Dusky (3) and Yellow-browed (5) but more importantly, it doesn’t show such obvious migration peaks in either autumn or spring, unlike Dusky which shows a peak in autumn but not in spring, and Yellow-browed, which shows peaks in both autumn and spring. These results are reflected in the Avifauna graphs but I don’t know why these three species with apparently similar distributions should show such different timings – anyone offer any suggestions?

4)        Two-barred (Greenish Warbler) – can be seen throughout the winter and spring but note the concentration of birds passing through in late October

5)        Yellow-browed Warbler. Note the red dots showing numbers in early 2008. This was the coldest winter for 40 years with a very cold spell in late January/early February. Yellow-browed Warbler disappeared from Po Toi at this time, in fact I think all the birds died in the cold weather. Unlike both Dusky and Pallas’s which didn’t seem too much affected. Obviously more hardy species than Yellow-browed.

6)        Ferruginous. A spring only species, genuinely rare in autumn. Avifauna lists two autumn records and there have been three since, including this one in 2008.

7)        Dark-sided Flycatcher. An autumn only species, the last official spring record was in 1994. Ho Fai suggested another autumn species Yellow-rumped which is very close to Dark-sided, the graph is below, but usually finishes autumn migration by the end of September and second half October and November records are very rare. It also has three recent spring records (plus one in Avifauna), including this one in 2006



8)        Mugimaki Flycatcher. John Holmes suggested Asian Paradise but that species is much earlier in autumn and rarer in spring. Here is Asian Paradise



9)        Asian Brown Flycatcher

10)        Narcissus Flycatcher – similar to Ferruginous but more regular in autumn in recent years, at least on Po Toi

Tie-breaker – Tree Sparrow, a migrant on Po Toi with no birds over the winter. Gary suggested Barn Swallow, which has a similar pattern but is earlier in spring with most records in March. Here is Barn Swallow



Here are graphs for some other species mentioned, Eastern Crowned Warbler (honestly)



Grey-streaked Flycatcher  



and Chinese Sparrowhawk.



I’ve had to cut off the highest counts of the last species, which were 780 (16 April 2006), 53 (22 April 2009) and 1440 (15 April 2010), otherwise you couldn’t see the smaller numbers.

Prizes – well, John Allcock got them all right but he had a lot of help from earlier respondents so I’m going for the early birds, Gary Chow and John Holmes, as joint winners of the First Prize, a free night on Po Toi in January. In fact, it’s good to have two winners, what better way to keep warm on a cold winter’s night than sharing a bed. Just let me know which day you want to be there and I’ll make the arrangements.

‘Bird Brain of Po Toi’ – I think the title has to go to the one who correctly guessed the tie-breaker, bittern. So next year, you’ll have to follow the English proverb ‘Once bittern, twice shy’ (I've been wanting to say that for ages).

[ Last edited by wgeoff at 28/12/2011 13:23 ]

wgeoff

Thanks John, I agree with your assessment.

There are similarities on spring migration patterns between Yellow-browed and some other species e.g. Little Bunting as here



a pattern which appears in Avifauna also. These species must use a coastal migration route in spring, perhaps as well as the more normal inland route which, as you say, by-passes Hong Kong

[ Last edited by wgeoff at 29/12/2011 07:21 ]

wgeoff

I don't seem to get that many at Po Toi, only singles. Maybe others have more but I don't think more than two, maybe three.