Friday 12 July 2019

Update on the Rutland Water Ospreys

Friday 12 July

The Manton Bay Ospreys Pandion Haliaetus

Mum, top left, with all four chicks
Following recent visits to nearby Rutland Water and especially two days ago with my friend Bryan Stapely on Wednesday 10 July, I managed to gather sufficient information to give an update on this year's Osprey breeding season.  The original nesting site in Manton Bay is still being used and this year's pair appear not only to have produced four eggs but all have successfully hatched and the chicks fledged.  Ringing of the chicks took place a couple of weeks ago when the birds were about 5 to 6 weeks old and the wardens were able to confirm that there were two males and two females.  However, whilst three are now free-flying, the smallest at about six days younger than the third chick, is yet to leave the nest platform but, on the other hand, may have now done so since last Wednesday's visit.
Mum with two in the nest

Whilst this may be the only nest actually on Rutland Water, there are a further eight (8) successful breeding pairs within three miles and all use this water as their main feeding site albeit relatively nearby Eyebrook Reservoir just over the county boundary in Northamptonshire is also visited.

Mum with three in the nest and one along side
Further to these eighteen birds there are another nine non-breeding and/or sub-adults also summering in the immediate vicinity and also based on the fish supply at the above waters, plus, I am informed, occasional visits to the nearby fish farm!
Three chicks look like a bit of a squeeze

If the other eight pairs successfully fledge an average of two chicks each, and there certainly seems plenty of trout and roach to be had, the weather has been kind and the heavy storms in late June/early July came when the chicks were well developed, then it could well be that as many as 20 youngsters or more will make their first migration south at the end of the season.  Amazing to think that there could be as many as 47 or even 50 free-flying Ospreys in the area - and this without adding any migrating individuals from other parts of the country.  However, we are constantly reminded that the mortality rate is very severe with, probably, only about 30% of the youngsters surviving to return to their birth site in a couple of year's time. But, even so, that could result in an increased population in the Rutland Water area to the mid-thirties in the near future.  Many congratulations to all who have been and are still engaged in this most successful project.
Three in the nest.  How close is this?  All right, the reflection is a give-away as the shot was taken from the live screen in the hide!
Mum with youngest
Then was another
All present and correct but note the passing Common Tern Sterna hirundo.  Dad is expected back any minute with afternoon tea.
One of the young preferred to roost on a dead branch close to the water (see next photo)
A second chick seemed to prefer to rest higher in the tree, two thirds up on right-hand side. Note dead branch below which held the above chick.
But we all know what happens when dad returns open empty-handed - or, perhaps, empty-footed in this case.  No food for the family so you can jolly well take your self off to the isolation tree where he is perched two-thirds up  near the centre and, presumably, working up some energy to go off and start fishing again.


Check out the accompanying website at http://www.birdingaxarquia.weebly.com for the latest sightings, photographs and additional information

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