The Osprey World, as only they know it!

Newsflash - Bassenthwaite a new tracking project planned for their chicks (I assume) in 2010.

I have put this here before starting a new thread say 'Bassenthwaite Tracking Project 2010', any views on this, on the one hand we don't want too many threads and on the other, as someone said before, things can get lost, if we don't?

Satellite trackers used for Lake District ospreys

jsb Thanks for the news - that's interesting.

I don't feel we need a separate thread for this. There won't be much more to say about this till we hear if it's happening, probably about ringing time, so it would sink out of sight in the interim, plus I'm not convinced we would want to track Bassenthwaite ospreys separately from all others.  

My suggestion:

1. Convert the "Returning Ospreys" thread started by Vespa Crabro to "News from other Nests 2010" - this would require Vespa to go in and amend the Title, as it's part of the opening post. We can then use the thread though the summer, to post this kind of item.

2. If the Bassenthwaite tracking project goes ahead, include the bird(s) in our future (non Loch Garten) Satellite Tracked Ospreys - August 2010 thread. We will potentially be running this alongside separate threads for Rothes (we hope) and from what's been said by Richard, some of this year's LG chicks.   

Sue C - Agreed, thread title amended

Thanks JSB. This is really great news. Lets hope that the pair return and nest successfully. In my opinion we should add it to the satellite tracked birds thread but I would like to hear what others think.

Lake District / Bassenthwaite websites. For reference.

http://www.ospreywatch.co.uk/

http://www.bbc.co.uk/cumbria/content/webcams/osprey_video_webcam.shtml

http://www.flickr.com/photos/ospreywatch/

Thanks for replies so far, we have plenty of time to organise how we wish to follow this development. Any local input from Bassenthwaite regular visitors would be worth hearing.

Postings from Daily Update pages starting 12th May 2010

jsb:

Annette in SoCal:

Ej is very alert, looking about. Poor dear has snow on her tail feathers - she seems to be calling - I can see her shaking periodically - but I can't hear anything; just the usual background twitters and the buzz.  Can anyone explain why birds would leave the warmth of another climate to have chicks in such a chilly place?  OK, so they like the long days, but how does that affect mating and reproduction?   Uh oh. She's getting up and fussing with the eggs; now settling down again.  Come on Odin, think EJ could do with a break.

Annette: Why here? All this way to reproduce! Many have asked this good question. I am no expert, but as you say the daylight duration is the key. Here is the daylilght by latitude, LG is approx 57 deg and Guinea Bisseau about 12, let's say. 50% more daylight approx and the birds are usually active in dusk/dawn to maximise the time to rear their young, so it will be interesting this year to estimate the gap between the chicks digesting their last meal of the day and receiving their breakfast, the next.

http://astro.unl.edu/classaction/animations/coordsmotion/daylighthoursexplorer.html

What I find fascinating, apart from the migration aspect, which is my favourite, is the rapid growth of the chicks, with almost constant feeding, over a daylight period of 50% plus compared to African locations. They develop from the egg hatching at a weight of ?grams, not very much anyway, to young juveniles at the fledging , then migration stage, to a weight in excess of 1500 grams approx in about 100 days, from say late May to late August. Phew, that is some going, comparison to human development is pretty near impossible in that timescale, we are still not managing to have proper bones, by then, only soft ones! Watch out for the 'reptilian' stage that the chicks go though for a few days, which shows the traces of avian evolution very well, from their ancient ancestors.

Fascinating stuff. So I think rather than just the mating and reproduction, it is the growth opportunities, afforded by the fishing hours in the day, that drives the migration north. In round numbers, if they could manage say 20 hours max per day for 100 days, less a bit for the time that the parents stop feeding the chicks, to encourage them to fish for themselves, so maybe 20 x 90, would be better, that's 1800 hours of food supply.

I'm sure that others may wish to add to or comment on the above. With that in mind I shall copy this to one of the blogs that I started last year, to keep the subject in view, as it could be lost on the daily pages. Now I just have to remember what the blog was called! I shall look for it, after a cup of coffee.

Lindybird:

thanks for interesting info. I have also been fascinated by the rapid growth of the chicks, as well as their ability to migrate so soon after fledging. Good idea to post the info elsewhere.

Glad that some of you can see the pics put on recently - for some reason, I can see the pics posted by others but not by myself!  Here is one of EJ arriving with the red moss, hope you can see it:

Sue C:

Just to throw a spanner in the works, migrating north to breed clearly isn't essential though, as ospreys can and do breed around the

Mediterranean (Corsica, Majorca, Morocco and now southern Spain) on the Canary Islands and I believe even the Cape Verde islands. I know some of these populations aren't thriving, but that's more down to loss of habitat and past persecution. I wonder if the period to fledging/independence is longer in these places?

DjoanS:

fascinating information about the osprey chicks .... I am learning something new almost every day on these blogs!

Reply to Sue C:

thanks for info about the Mediterranean and other ospreys breeding further south - all interesting facts to file away in my brain

jsb:

I was intending to do some gardening, but driven indoors by the cold! Persecution of birds by our ancestors, before the days of farming, going way back to the early days of man seeking out a meal, would not exactly encourage the birds to set up home, also the indigenous hunting creatures of that time, may have a bearing on the  choice of nesting sites. viz. The geese and the like, preferring the Arctic Tundra to breed. The reverse argument as you say, is that now that reserves have been set up to encourage breeding, the birds may be in the process on changing these nesting habits. Now I shall put on a jacket and brave the outdoors!

Lynette:

Hi jsb, all interesting information as well as your earlier one - perhaps LG can throw a light on whether its longer in warmer places or not.

Another point to ponder:  Australian ospreys don't migrate at all. They live and breed permanently in an area, perhaps moving a little to follow changing sea currents which carry their food.  They are found from the tropics to Tasmania, and all seem to be able to feed their chicks adequately without problem.  In the north of Australia, it has been found that the ospreys have changed their diet to include bats.  Perhaps this because of the milkiness of the sea there at some times of the year. or perhaps because the bats are available at night..

Wattie 15: Yes, I am sure your point is valid, almost like a sub-species that have evolved without the need to migrate. In places like East Africa/Middle East, or in Florida too, I think I recall semi resident populations. Here is a NASA photo taken in Florida yesterday of an Osprey 'family'......  I was following some Central American ospreys last year and recall that some did not travel very far north to breed.

The NASA photo of a family would indicate that mating/breeding must have taken place very early this year.

http://www.nasa.gov/multimedia/imagegallery/image_feature_1663.html

Love the NASA photo, jsb.