Friday, 23 November 2007

Questions and Answers

One of our regular viewers, Jennie in Hong Kong, recently posted some very pertinent questions in this blog's comments. We've put these and a few others we've received in bold, and have tried to answer them as best as we can.

Where would the birds be if the box were removed? - well, they would still be on the Cathedral, it's as simple as that. They chose the Cathedral as their favourite site in Derby, England, from which to hunt and on which to roost - just as other peregrines have probably done on and off here for hundreds of years.

Why do they return to the nest platform each day? Probably to assure themselves that it's still OK, and to reinforce their possession of it against any competition that might Adult peregrines in a rare out-of-season display of static head-bowing, November 13th 2007. Female is on the left. (Note the leafless trees down below. It's autumn here now, with the birds expected to start breeding again next March/April)come through. We know that they have been undertaking occasional nest-scraping actions at least since mid-October, and in certain light the depression in the gravel on the left side of the platform is very clear to see. The picture on the left was taken on November 13th at 8.30GMT, just about 1.5hrs after dawn broke. The male on the right remained static, with head bowed, for about five minutes, and the female on the left didn't move much either. The picture below was taken on 18th November after the first snowfall of winter in Derby - the nest scrape is highlighted well under the infra-red light.
With snow on the ledge, the nest scrape stands out clearly under infra-red light. Picture taken Nov 18th 22:30 GMT. Click to enlarge image.
I didn't see them nest-scraping whenever I watched. Do the birds do this at a particular time, say in the morning or at night? Is this the job for the male or female?
I'm not sure there's a particular time that they do this. It's quite a rare event to see this time of year, and with the 15 second change of images it could easily be missed. You can see a video clip here As stated above, the most reliable time to see the birds is shortly after dawn, so try watching around 7am-8am local time. From our experience in 2007, we'd say that it's the adult male who does most of the nest-scraping.

Would the parents recognise the juveniles from this season if they returned? Well, based on the evidence we saw earlier in the year, we think they would. Visit our blog entries for March 21st and 6th April and you'll see two of our YouTube videos showing one of the previous year's chicks on the nest platform. Not only were the parents not bothered by their offspring's presence, at one point the adult male seemed quite intimidated by the young bird. I'm sure the juveniles were only tolerated because they were recognised as being the young of these particular birds. Elsewhere the young of other peregrines have been known to stay around and help feed the new season's chicks.

Now that the babes are ringed and fledged..have there been any sightings? And if so is there a place where they are logged and can be viewed?
The last known sighting of one of the peregrine chicks from 2007 was about 10 miles away, where a colour-ringed peregrine was seen in early October. It wasn't possible to tell if it was oo1 or 002. We will, of course bring you news of the juveniles as soon as we hear it. As far as I'm aware though, it's not currently possible to look up bird ringing results online - but I'll amend this if I'm proved wrong.

Nadine in Australia emailed us to say that the night-light on the left hand side is not working and hoped that we would get it fixed as our night time is her daytime, and is the only period when she can watch for the peregrines. The problem is partly due to the fact that this camera has sagged slightly over the last few months. It now points down and "sees" more of the floodlighting on the cathedral tower, and is fooled into thinking that it's still daytime, so it turns off the infra-red illumination. When we next abseil down we'll try and make all the necessary adjustments, but in the meantime we've remotely fiddled with the camera iris, and it seems to have done the trick. The night-time IR illuminator now works more often than not.

Why does the camera picture freeze up ocassionally? This is usually a problem with the video server inside Derby Cathedral, or our link to Streamdays. Once we're aware of a problem we can normally re-boot our equipment remotely, but sometimes we have to climb the spiral staircase and start the equipment manually. A break in signal in mid-November was caused by the accidental disconection of the pwoer supply to some receiving equipment inside The Silk Mill Museum, through which our signals pass. Thanks to the guys from Capita IT Services for remedying that one.


Anonymous said...

Thanks Nick for your answers. Jennie, HK.

Ash said...

Now that the babes are ringed and fledged..have there been any sitings? And if they are sighted is there a place where the sightings are logged and can be viewed?

Anonymous said...

12.34am B.C. Canada
falcon on left of the nest, breakfast on the right

Anonymous said...

The "breakfast" has now gone, it has been there for more than a day actually, it looks like a dead bird. Jennie, HK.

Anonymous said...

Something wrong with the right camera! Can't see the image clearly. Jennie, HK.

Anonymous said...

The right camera is back to normal now. Jennie

Project Member (Derby Museum) said...

Sorry for the break in the camera feed before and during lunchtime today (our time). I was up inside the Cathedral Tower installing a replacement video recorder and rewiring the cameras and video switches. You'll probably have noticed the signal coming and going.

BTW: There's a bird on the ledge below the right side of the platform at 20:00 local time.

Liz, Derby said...

Bird on the right hand camera 10.40am GMT. First time I have seen one for quite a while!

Anonymous said...

what is going on with the camaras have they broken or switched off. could someone please give us some info as to what is going on.

Anonymous said...

The time shows the camera has stopped since 4pm 19Nov. Jennie, HK.

Project Member (Derby Museum) said...

I'm afraid our connection into/out of Derby Cathedral has broken somehow. In an attempt to solve the problem I rebooted all our equipment today, but to no avail. This means I'll have to raise a call to our IT support people to check the link. Whilst it might just turn out to be a disconnected cable somewhere, it's more likely to be a high tech problem that only they can fix for us. From the cathedral tower, the internet picture goes by a 2GHz radio signal to the nearby Silk Mill Museum. From there it goes via a laser connection to the Assembly Rooms, and from there into our Council House and thence out to Streamdays, and then to your PC. The problem is definitely at our end, and not with Streamdays as I am still not able to connect with the cathedral video server direct from my office, as I normally can. This is a direct connection and does does not involve any third party.
So, we're sorry to disappoint viewers, but we will get things back running as soon as we're able, though we have been lucky to have the camera feed for longer than we'd expected.

Nick M.

Project Member (Derby Museum) said...

The broken webcam link has now been rectified. It turned out that the radio receiver link inside The Silk Mill Museum had accidentally been switched off. Not so hi-tech after all.