butter

Came across them yesterday in the rough open ... didn't notice any warning from the parents, almost stepped on their eggs when suddenly one of them flew away, drawing my attention away. Then the other one flew in a slightly different direction when I started to talk. Both seemed to be taking off not from the eggs but from somewhere nearby (should be very close but I didn't see where it took off exactly). We left immediately hoping that they'd return to care for their eggs. Watching from a distance, noticed one of them returned closer and closer after some minutes.
They didn't fly high, just kept skimming over very low (less than 2 m), I could only see their back and noticed the white patch near the wing tip.


the eggs are of the size of those turtle doves's


[ Last edited by butter at 2/06/2011 16:42 ]

subbuteo

Looks like Savanna Nightjar!
Dylan

ajohn

Yes, definitely Savanna Nightjar. Your photo shows a female - note that the pale wing patches are buff rather than white and the outer tail feathers are not white.
Congratulations - they are difficult birds to see during the day time, and it is very unusual to find the nest.

Please do not provide any information to others about the exact nest location. The birds may be sensitive to human disturbance, and for a species nesting in the open the eggs could be in danger if they are left exposed to the sun. But do please try to remember to submit the record to the HKBWS so that we have a better knowledge of distribution and breeding behaviour of this species.

HFCheung

Rare photo of the eggs of this species.
I suggest we stay away from nests / eggs.  Keep a fair distance and do not stay long.

HF Cheung

[ Last edited by HFCheung at 1/06/2011 20:26 ]

butter

Quote:

Original posted by ajohn at 1/06/2011 18:44
Yes, definitely Savanna Nightjar. Your photo shows a female - note that the pale wing patches are buff rather than white and the outer tail feathers are not white.
Congratulations - they are difficul ...

I did guess it's a nightjar but since I'd never be sure of spotting one before. I couldn't be sure it was that bird. Is it normal to nest in the open under such a hot weather? The sun was scorching.

you mean the one in the lower right hand corner? is there another one in the upper left (not sure)? I remember a darker one took off before the brighter one. The latter seems to be the one in the lower right.

... should I download the rare/non-rare bird record form? ... yet, I've tried downloading both w/o success. Could anyone email the proper file to me pls?

Quote:

Original posted by HFCheung at 1/06/2011 20:23
Rare photo of the eggs of this species.
I suggest we stay away from nests / eggs.  Keep a fair distance and do not stay long.

HF Cheung

of course, that's why we left them as soon as we took a snapshot of the eggs. May I ask if they'll still be there breeding in Oct? ... 'cos I was preparing an event in that area for Oct. Since I couldn't disclose what's there but then I have to close the area, that'll be a bit awkward. No matter what, I'll try my best to help protect them.
BTW, if I wasn't mistaken, I'd encountered another one somewhere nearby last year but in later months. Not fast enough to take any photos. Also during daytime in the rough open.

[ Last edited by butter at 3/06/2011 16:25 ]

ajohn

Yes, it is normal for nightjars to nest in the open like this. The adult will normally spend the day shading the eggs from the hot sun (this is why I mentioned the dangers of keeping the birds away from the nest - it sounds like you did the right thing by only looking briefly at the nest, then moving away to a larger distance so that the birds could return). The most dangerous time for disturbance will be now, while there are eggs. The young should be able to move away from danger even when fairly young. The nesting should be finished long before October (the young will probably start flying in mid-summer), so I do not think this will interfere with your event.

You may be right that there is another bird in the top left of the picture, but I'm not sure whether this is actually the shadow on the rocks.

You can download the non-rare bird record form at:
http://www.hkbws.org.hk/web/eng/download_eng.htm
http://www.hkbws.org.hk/web/chi/download.htm

butter

Quote:

Original posted by ajohn at 2/06/2011 17:01
Yes, it is normal for nightjars to nest in the open like this. The adult will normally spend the day shading the eggs from the hot sun (this is why I mentioned the dangers of keeping the birds away fr ...

Record just sent right now, along with a map. But the one sent to this address (recorder@hkbws.org.hk)is returned.  
We'll be having an orienteering event in autumn, that's why I worried much about having participants running in that area (not only on frequented paths). It's a relieve to hear that the birds will be left by then.
Judging by their Chinese name, I used to have a wrong concept that they stayed in the forest. Do they give warning when people wander near? ... there're birds chirping but not when we're near the eggs. It's a close shave that I didn't step on them.
How do the adults shade the eggs?

[ Last edited by butter at 2/06/2011 18:00 ]

thinfor

Hi Butter, don't know you're an orienteering guy!  I've once participated in 'RUN O' frequently, though I seldom join now.

So I might be able to guess where the photos were taken.  So if you're one of the organizers or whatever related to the organizing committee, just try your best to convey our idea and see whether minimum occurrence can be done to the birds.

Birdwatching can be even more widespread if all those outdoor lovers keep an eye on our beloved creatures.  I am sure that with adequate education, we can save our place to accommodate more birds.  

ajohn

Quote:

Original posted by butter at 2/06/2011 17:41

Do they give warning when people wander near? ... there're birds chirping but not when we're near the eggs.

Savanna Nightjar do give a fairly quiet 'chook' call when disturbed, they also have a call 'schooeep' which is used for display. If you heard the brids when they were away from the nest, they were probably trying to get your attention to make you follow them. Most predators would usually follow the adults, rather than thinking to look for the nest. Many birds use similar 'distraction displays'.

Quote:

Original posted by butter at 2/06/2011 17:41

How do the adults shade the eggs?

The same way as other birds - with their bodies. As the bird covers the eggs, it's body shields the sun and keeps the temperature right for incubation. Although the egg needs warmth to develop, the direct sun it so hot that an egg in the full sun would simply cook. It always amazes me how some birds are able to sit in the sun all day during the heat of the summer without suffering from heat stroke.

butter

Quote:

Original posted by ajohn at 3/06/2011 13:44
The same way as other birds - with their bodies. As the bird covers the eggs, it's body shields the sun and keeps the temperature right for incubation. Although the egg needs warmth to develop, the direct sun it so hot that an egg in the full sun would simply cook. It always amazes me how some birds are able to sit in the sun all day during the heat of the summer without suffering from heat stroke. ...

Right, it's hard to perceive how they can stand the heat with feathers all over the body. Why don't they lay the eggs under the shade (at least not in such an open area)?