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Thursday, 11 April 2013

Clutch complete! No. 4 is laid. Update 12 April: visit from a juvenile!

Thanks to quick eyed observers Mike Clarke, AnnieF and also Julie, the fourth egg was laid at 15.28 today (Thursday 11th April)...
A full clutch - taken by HelenSara at 1800 hours on Thursday
This is great news after all the trials and tribulations of the past two weeks. Incubation proper will start now.

Now the clutch is complete (it is very rare for peregrines to lay five eggs) we have about a month (30 days) to wait until the eggs begin to hatch.
During this time, the female bird (the falcon) will do the majority of the incubation. Being 15% bigger than the male, her brood patch (the bare area on her underside that comes into contact with the eggs) is much better able to thoroughly warm the eggs than that of the smaller male (tiercel).
He will do all the hunting now - she won't do any..
When he arrives back with food she will slip off the eggs and he'll take over while she feeds, preens and stretches and (sometimes) flies off for a wash and brush up. As soon as she's ready to get back ont he eggs she'll make her intentions clear and the male will ski-daddle fast!
Incidentally we have no idea where they go to have a wash but, like all birds, they must be doing this to keep their feathers in tip top condition. Maybe there's a puddle on the top roof of Jurys Inn - or perhaps they find a gravel bank on the River Derwent somewhere nearby to their liking?

A Request :
Although this blog is primarily about peregrines, one of its other purposes is to try to encourage people who are drawn to watching our birds to go on to do something FOR the environment in one way or another. It could be by making a donation, by joining a local wildlife trust or some other wildlife organisation, by doing some voluntary work or, see below, by signing a petition.
Part of our work with this project has been and continues to be getting the peregrines and their lives into schools so that children can learn about these birds, how they came back from the brink of extinction and how they are now thriving once more, especially in towns and cities.

Children watching the peregrines
And of course, we've made contact with some inspired teachers in and beyond the county who have seen the potential of this project and also how they can use it to teach the curriculum.
Now, however, there are governmental moves afoot to take environmental learning out of the school curriculum and the Wildlife Trusts are among many others who are very concerned about this development.
See  http://www.derbyshirewildlifetrust.org.uk/news/2013/04/05/help-us-keep-nature-national-curriculum  and (nationally) http://www.wildlifetrusts.org/news/2013/03/20/gove-knows-not-what-he-does

On these links there is a consultation/petition so if this does concern you (and of course there's no obligation whatsoever), please consider expressing your concern.
Thank you - but be aware that you only have until 16th April (next Tuesday) to do this!

 A visit from a juvenile - screen grab - Chris Fairbrother
UPDATE Friday evening: Chris Fairbrother captured a screen grab above which clearly shows a juvenile peregrine on the ledge above the nest (with an adult flying off towards Jurys Inn). There appears to be no colour ring on its left leg so, unless a colour ring has fallen off, this isn't a Derby youngster. It remains to be seen if this intruder is tolerated or chased off, assuming it tries to hang around that is. And just when we thought things would quieten down too!
NB

Nick B (DWT)

38 comments:

  1. Well just as I thought, I have been out today and get back to have missed the fourth egg being laid! I am glad they have a fourth egg and RJ was absolutely right about the 7 day period. We just sit and wait now, time to get the housework done haha.

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  2. Congratulations on egg # 4!
    Regarding 5-egg clutches: it seems that those mostly occur in the USA. We now know of 9 nests with 5 eggs: 1 in Europe, Brussel- St. Michael and St. Gudula Cathedral.
    Dayton Ohio, Jackson county MI, Louisville Kentucky, Omaha Nebraska, Pittsburgh-Cathedral of Learning, Richmond Virginia, Savannah Illinois, Wilmington Delaware.
    Dayt from the Peregrine Falcon nesting calendar 2013: http://sites.google.com/site/nestkalenders/home/slechtvalken

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  3. How fantastic...Derby 4 Nottingham 3........ oooops x

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  4. Well done Mrs p I knew she would do it! I had every faith in her! Can't wait for the months ahead! From Christine

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  5. Just as you said Nick, the falcon is feeding on the tower whilst the tiercel is on the eggs. A lovely clear picture too.

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  6. Friday: a damp morning in Derby and still quite chilly....but nothing these birds can't handle.
    Over thousands of years they have evolved to cope with whatever the weather throws at them. On most natural cliffs they will have a few alternative nest sites to choose from so if one has become covered with snow there may well be another facing a different direction, or with a deeper crevice, that is snow-free. Our Derby birds don't really have that option - it's the nest platform or nowhere!
    Nick B (DWT)

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  7. I'm very pleased Mrs P has produced egg 4. I was confident it would happen. I'm not an expert but it was just a very strong feeling.
    It's very unusual, I'd say unprecidented, for the Project to get on a "soapbox", so this should alert everyone that it's a really serious thing that they're worried about. I've signed the 38 Degrees version because IMHO sheer weight of numbers of public opinion is the only thing that moves mountains, not well argued and sound cases. I'm not sure if there's an official government consultation site? If there is, I'd like to comment on it because there are other Gove ideas that worry me.
    We have a miserable day down here in Bucks too - but at least that bitter cold is gone! Our Mrs P (Mr too) is sitting faithfully, not sure what "D" day we expect with our two funny eggs. Could spring really be on the move? My flock of siskins are still shovelling away the food in my garden, are they getting "fuelled-up" ready to go?

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  8. Thanks for your support Sue. This particular 'soapbox' is really crucial both in general and also specifically for our work in schools with this project. Teachers have to justify having external organisations coming in and usually do so with the peregrines by pointing to the 'caring for the environment' bits of the curriculum. If that goes, then so may we.
    'Soap boxing' like this will not be a regular feature on this blog but this particular case is one that the lead partner in this project (the wildlife trust, both locally and nationally) is very concerned about and because it relates directly to our work in schools.
    Nick B (DWT)

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  9. Sue - lots of rain here this morning (rather welcome since the surface of the soil has become really dry) but now the sun is out again and it's warming up...
    Good luck to those Bucks eggs and their 'sitters'!
    Nick B (DWT)

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  10. Just as I had a feeling that the Derby peregrines would breed OK this season, I have a feeling that climate change is the reason we have had strange breeding results at Aylesbury. It was obviously a huge issue with the Nottingham site. I believe it's a massive mistake to try to ignore climate and hope it'll go away and to stop teaching it in school. It has a huge impact on us humans in general and the peregrines in particular, the peregrines that we watchers all enjoy watching. Go on, get those petitions signed, you have lots of spare time now we're all waiting for the incubation to get done :)

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  11. I wonder if the juvenile peregrine is one of the derby's pair from last year. How great for it to be seen and to get a screen grab. Thank you Chris Fairbrother! A great capture!

    What are the chances of it being from a different nest I wonder. It would be more likely I think to be one from ours last year but I don't know how it could lose a ring. It does look a bit disheveled to me.

    Maybe it won't be all that quiet now, if this bird decides to stay around.

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  12. Ps. there is some sort of prey on the tower, has anyone identified it or seen it brought in?

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  13. I've been wondering about the prey too!

    Some screenshots of the juvenile's visit on your Facebook page.

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  14. Hi Phoebe: yes that is a prey item but I'm not at all sure what. Seems brown coloured so possibly a woodcock grabbed on its northward migration? Or it could be a water rail (Joyce Sawford sent me a photo of such a rail she found dead under the tower a week or two ago).
    Now that the birds have eggs we are not allowed to lean over the east side of the tower top and will be putting a notice up to this effect on Monday. So I'm afraid the identity of the prey will have to remain a mystery.
    Nick B (DWT)

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  15. Sound has now been restored to our only fully live webcam feed: Stream 3.

    We have reduced the time it plays for without refreshing down to about 8 minutes. We hope this doesn't inconvenience people, but it does save us wasting a lot of bandwidth.

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  16. I was going to query whether the dead bird on the ledge could possibly be the juvenile that was seen yesterday? Having looked again I don't think it is but is there any evidence that adult peregrines would kill and "cannibalise" their own species? And should I sign this "also Julie"? :-)

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  17. Hi Julie: I don't think the dead bird is the juvenile peregrine - it doesn't look like that.
    Checking up in the peregrine 'bible' - Derek Ratcliffe's monograph entitled 'The Peregrine Falcon' (publ. Poyser Press) - he was aware of only one case (in Montreal) of peregrines fighting with an intruding pair - with the result that one of the males was killed and part-eaten.
    Such deaths appear to be extremely rare. Usually intruders soon give up when the residents both attack them.
    However Ratcliffe does say that mystery 'third birds' do sometimes appear at nests and can appear to be tolerated - perhaps because they are juveniles from a previous year...though he had no evidence to that effect.
    Nick B (DWT)

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  18. No sign of any peregrines down at the cathedral early this morning (Sunday) but a pair of mistle thrushes on the grass on The Green was good to see.
    A milder day but with a strengthening southerly wind.
    Nick B (DWT)

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  19. Well done to the screen grabbers who spotted the juvie! When do juvies change into adult plumage? The visit shows what an attractive roost the cathedral is :) I have signed the petition... closing date April 16 so do join if you wish.

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  20. Nick B (Derbyshire Wildlife Trust)14 April 2013 at 11:18

    Hi Caroline: thanks for signing the curriculum change petition.
    Re. juveniles, Ratcliffe says that there is a good deal of variation in when they moult into a more adult plumage. It could be as soon as the first March of life but usually is later - April-June - so when they are 10-12 months old.
    Some observers say that peregrines become more blue/grey as they get older (and that the yellow on cere, feet and round the eye becomes more intense).
    Some birds in a brown, juvenile plumage (presumably about one year old) have been recorded breeding at this young age - but when they do, it is always with an adult mate.
    I'm sure that our female was a much paler bird back in 2006/7, suggesting she was perhaps only one or two years old when she began to breed at Derby. The male always looked adult so is probably older than her.
    Nick B (DWT)
    Nick B (DWT)

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  21. Hello we are Oak class from Holmesdale Infant School in Dronfield. We have a few questions that we would like to ask...

    What do peregrines like to eat?
    How does the mother peregrine hunt if she's incubating the eggs?
    How fast can they fly?
    How big are they?
    Are the eggs smaller than chicken eggs?
    How do they hunt/catch their food?
    Do they hunt food bigger than themselves?
    when are the eggs going to hatch?

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  22. Hello we are Oak class from Holmesdale Infant School in Dronfield. We have a few questions that we would like to ask...

    What do peregrines like to eat?
    How does the mother peregrine hunt if she's incubating the eggs?
    How fast can they fly?
    How big are they?
    Are the eggs smaller than chicken eggs?
    How do they hunt/catch their food?
    Do they hunt food bigger than themselves?
    when are the eggs going to hatch?

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  23. Nick B (Derbyshire Wildlife Trust)15 April 2013 at 11:02

    Hello Oak class: sorry that you probably missed all the egg laying while you were on holiday but now you are back at school - wow - those are some great questions! Here are some answers which may help you:
    What do peregrines like to eat? Other birds and quite a wide range of different species too from quite small ones like finches to birds as big as ducks, magpies and gulls!
    How does the mother peregrine hunt if she's incubating the eggs? She doesn't. She leaves all the hunting to the male. He brings back food for her every day. She leaves the eggs to eat it and the male sits on the eggs while she's away. Once she's eaten (and had a quick wash and brush up!) she pushes her mate off the eggs and sits on them herself.
    How fast can they fly? Peregrines are the fastest birds on the planet! When they perform their vertical dive called a 'stoop' they have been timed at over 200 miles per hour! That's faster than a formula one car isn't it?
    How big are they? Just a bit bigger than a crow - so not very big really. And the female is bigger than the male by about 15%. She's the boss!
    Are the eggs smaller than chicken eggs? About the same size as a large chicken's egg.
    How do they hunt/catch their food? They have two methods mainly. In open country such as the moors of Derbyshire they will fly very high, watch for a bird flying down below them, close their wings to form a bullet shape and dive vertically down. As they get near the prey they put out their feet and hit it at speed. Sometimes the prey is killed instantly and the peregrine grabs it in mid air OR it falls to the ground and the falcon follows it down.
    The other method - and the one we see round about Derby, is for the falcon to fly up behind a flying bird such as a pigeon and simply grab it without the prey seeing it coming. This uses less energy than the first method and is safer for the falcons when there are buildings around them.
    Do they hunt food bigger than themselves? Very occasionally they will but usually they choose prey that is smaller than them.
    When are the eggs going to hatch? The incubation period is about 30 days....so since the last egg was laid on 11th April, maybe you would like to work out when they will hatch for yourselves?

    Hope those answers were OK? Let us know if you have more questions!
    Good luck and keep watching the web cams!
    Nick B (Derbyshire Wildlife Trust)

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  24. Thank you for your good questions, Oak class, as I learnt something from Nick's answers too. He knows a lot about peregrines, doesn't he? He also kindly answered my question about the colour of the feathers of the young birds. Imagine being born as a fluffy white chick and then growing speckled brown feathers before you get your true grown-up grey-blue feathers.

    Nick, so peregrines deepen in plumage perhaps whereas we humans go grey. I can see I am going to be buying a copy of Ratcliffe at this rate as I found the weblink to his pages on the egg-laying intervals very interesting too. He also spoke about the slight differences in timing between nests North and South. Thanks for your time.

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  25. Oak class' guesses for the eggs hatching doesn't seem to have sent properly this morning!!.....

    Oak class (year 2) think the eggs will hatch between 10-16th may, but most of us think they'll hatch a little after the 11th... Maybe the 12th&13th.

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  26. For the first time, I have seen a pellet in the scrape. I didn't see the falcon produce it. At least that is what I think it is behind her towards the front.

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  27. Ho Phoebe: yes that looks like a pellet alright. They are greyish when dry and about 4-5 cms. long generally. I find them often at the base of the tower. They don't usually contain anything hard, just bits of feathers.
    Nick B (DWT)

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  28. That juvenile isn't an Aylesbury bird either. We've only had two (hatched 2012) and both were ringed. The large coloured rings are the same as the Derby ones (sorry) - orangey-red and they had black letters - LA and LB.

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  29. Children from Holmesdale Infants School have sent a lot of really good questions but for some (IT) reason these haven't appeared here on the blog comments. So I will copy them and answer them at the same time - if I can!
    Nick B (DWT)

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  30. Oak class, Holmesdale Infants

    We think the peregrines are beautiful. We've looked closely at the patterns on the feathers that are on the back of the bird.

    Will we see the female eat her prey?
    when do the peregrines go to sleep?
    Reply: Hi Oak Class: yes, peregrines are indeed really beautiful birds when you see them close up. I will send some photos to your teacher so she can show you the colours.
    The female eats when the male brings food back (he is doing all the hunting at the moment while the female sits on the eggs. He may come back anytime from the early morning to late evening. Depending on the size of the bird he has caught, he may come with food just once a day...or more if the prey was small.
    Our peregrines sleep (or 'roost') mostly after dark. They turn towards the stones of the cathedral, away from any light (eg from floodlights) and stay motionless with their heads tucked into their feathers.
    When there are eggs, the female bird will appear to nod off from time to time while she is sitting on them - but she never seems to be completely asleep - she needs to keep an eye open for any intruders that may come to the nest.
    Nick B (DWT)

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  31. sophie from oak class wrote:

    how fast can they fly.
    what dose it luck like when they fly.
    how do they stoop down to get food.
    what colers are on there wings and on there boddey.

    love sophie.
    Hi Sophie: some good questions there!
    Peregrines can fly quite fast in level flight as they fly from A to B and they can turn on the speed if they are chasing after prey.
    But when they hunt by diving vertically downwards from a great height, they can reach speeds of over 200 miles per hour (mph)! That is incredibly fast - faster than small aeroplanes and faster than racing cars in Formula One!
    This si why they are considered to be the fastest animal on the planet!
    When they fly they have a bullet shaped body and their powerful wings are pointed at the tips. This is a good shape to help them fly fast. When they drop down vertically, they close their wings and look rather like a bullet, pointed at the front and back and barrel-shaped in the middle.
    When peregrines are adult, they are a lovely bluey grey on their backs, wings and tail. Underneath they are paler, with bars on their wings and streaks down their bellies. Their faces are white with a black moustache running down form the base of the beak. their eyes are dark but are surrounded by a yellow ring. Their feet are also yellow.
    I'm sure your teacher will show you photos of peregrines if you ask her.
    Nick B (DWT)

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  32. evan oak class, holmesdale infants


    were do the eggs cum out.
    what dose it eat.

    Hi Evan: female peregrines have just one place under the tail - called the vent - out of which comes both the eggs and also their droppings or 'pooh' - though not at the same time of course!

    Unlike humans who can choose what they eat (from lettuce to meat and from potatoes to chocolate), peregrines have evolved just to eat meat. And that meat comes from the birds that they catch.
    Some (not all) humans eat birds don't they? Chicken, turkey and goose for example - while others are vegetarians and choose not to eat other animals. Peregrines can't choose different foods as we can - though they can decide what kind of bird they want to catch - but it must usually be a bird - very occasionally they catch a mammal such as a (flying) bat or a rat or squirrel even - but that is extremely rare!
    If you gave a peregrine a burger or a bag of chips it wouldn't see these things as food and would ignore them completely.
    Animals or birds that eat other animals we call 'predators'. Can you name some animals and birds that only eat plants and do you know what we call them? Your teacher will tell you the answers I'm sure!
    Keep asking good questions Evan - that's what learning is all about!

    Nick B (DWT)

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  33. tayla from oac class asked:

    when do the eggs hatch?
    when you are sat on the eggs is it comfy?
    haw do they now wen its moning?

    Hi Tayla,
    The eggs take about 30 days to begin to hatch out from the day when the parent birds started to sit on them and keep them warm. So our Derby eggs should hatch about 11th or 12th of May we hope!

    The female falcon develops a bare patch of skin on her belly (the feathers fall out there). This is called the brood patch and it has lots of blood vessels very close to the surface. When the female sits on the eggs, she wriggles down on them to bring them close to that bare patch. The blood warms the skin and the skin warms the eggs. I would think it is quite comfortable - but then I'm not a bird so I don't really know!

    Birds and other wild animals are very aware of the time of day. I don't mean they have wrist watches or phones that tell them the time! What I mean is that their lives are controlled by not only the time of day but also the time of year!
    They start to get active after dawn and then go off to roost or sleep about the time it goes dark.
    In winter, birds have to sleep for a very long time because it goes dark in the middle of the afternoon and doesn't get light again until about 6 or 7 am.
    In the summer, the nights are much shorter. So in June it doesn't get dark until maybe 11 pm and yet it comes light at 4 am! Birds adjust their lives depending on the day length. So as the days lengthen in spring, that's the time they start to nest and lay eggs.
    I hope that helps to answer your questions Tayla.
    Keep watching the peregrines Oak Class!
    Nick B (DWT)


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  34. A final question (for today anyway) from oak Class:
    william-j asks:

    how big ara a peragrens fut?

    Hi William:
    Peregrines have rather large feet for the size of their bodies and their legs. The part of the leg that shows is called the tarsus and it is about 50 millimetres long. At the bottom of the tarsus are the toes - three face forward and one backwards. The toes are longer than the tarsus but thinner. Both the tarsus and the toes are bright yellow! At the end of the toes are the talons or 'nails', These are very sharp and help the bird catch its prey.
    I hope that helps to answer your question!
    Nick B (DWT)

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  35. we are ecsited that the peregrin has layed four eggs.so we think the birds are doing a very good job of incubating the eggs. Theperegrins will keep them nice and warm. sometimes the peregins role the eggs about to make the
    chicks grow better.

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  36. Green Class, I think the peregrines turn the eggs so that they can keep them at a nice even temperature and to make sure that the chick inside the egg doesn't stick to the shell as it's growing. Perhaps you can work out how often the birds need to turn the eggs!

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