OSPREY CHAT - March/April 2019

SheilaFE said:

Not really Osprey chat at all, but folk on the LG forum might be interested in following this up to better the Community, of which we are a part.

I filled it in last night Sheila 

Not sure where to post this.. I def saw an Osprey today .  Alas no pics as was driving on a narrow road with view to water , bad corner, could not stop 

and def Osprey circling.  Suffice to say there are areas within a 9 to 13 mile radius of my sighting  where nests could be that are not public

. 

Regards 

S

This is a perfect place to put your post Sheena! How wonderful for you! Better do a return trip!!

I have come across some info which might be indicative of why so many ospreys are later than their expected return date.  

Clyde Muirshiel project -

Tag-n-Track (TnT) is using the latest technology to track birds locally and globally. This project is funded by Heritage Lottery Fund, Greater Renfrewshire and Inverclyde LEADER & Clyde Muirshiel Regional Park and started on the 9th of January 2016. It will run until December 2018.

One of the species we will be tagging and tracking is the Lesser Black-backed Gull. They are a much maligned species, most people viewing them as chip-stealing pests. However, are you aware that some of these UK amber listed birds (due to fewer individuals over a limited range) actually migrate to Europe and Africa in the winter time and then back to the UK in the summer?  The project will be using solar-powered Global Satellite Monitoring (GSM) tags fitted to the birds with harnesses which collects data between 10-15 times a day.

On their FB page there is an interesting post on Gary who I assume is a LBBG, which has a map of his migration route.

I don't understand "delaying incubation" after an egg is laid. I know Maya did it one year, and is the only time I have heard of it, and recall her not sitting during the night but I think she did sit on the eggs at times??

Could someone please explain this process.

Thanks in advance

Hi Karen, I think peregrines don't sit on the eggs full time initially, the below is from David Shaw Wildlife on chichesterperegrines.co.uk. Could be the same for osprey.
"First egg at 13.33 today…….quite normal not to sit on eggs until we have full clutch of four so don’t worry if egg left alone ……" Ian

Thanks Ian - interesting :-)

Karen, I found this snippet on the Dyfi site.

'Sometimes the first egg laid is not incubated, or it may be partially incubated, until the second/third is laid. This is an evolutionary strategy ensuring that the whole clutch hatch closer together than the timeframe (usually six days for three eggs) they were laid, giving all the chicks a greater chance of survival.'

www.dyfiospreyproject.com/.../facts-about-osprey-lifecycles

I believe Telyn did much the same last year. She didn't full time incubate until a couple of eggs had been laid.
This means that all eggs will hatch at about the same time.
Peregrines generally lay 4 eggs, but won't start full time incubation until the third egg has been laid.
Up to this point they will sit on the eggs to keep them warmish if the temp drops too much, mainly at night.