Sunday 18 August 2013

Robobirder

There's still a few flurries of activity around North Marsh and Hempholme from the second marsh harrier family.  To the best of our observations it appears two young have been reared on this nest.  As a suitable celebration of the harriers many thanks to reserve member David Bowen who has spent many hours compiling this excellent video of the birds - even capturing the food pass and a nice 'two fingers' to the herons that nearly saw them off back in June!:
A few final photos of the initial brood via Brian Colley here:
Now would seem a great time to demo the results of the prey log we had up in the hide.  Many thanks to all those who helped fill it out during the birds hatching to fledging period.  The chief purpose of the study was to build on what we had observed during the incubation period that prey items were not in conflict with game bird populations.  This is not to say we feel the birds under threat here - all young fledged and it is a great reflection on neighbouring landowners and shoots demonstrating an enlightened view especially given the range the birds travel and hunt and the bad press all raptors get from some quarters.

As a proviso please remember this data was compiled by multiple and not necessarily experienced observers and many unidentified items were simply unlogged.  But it does serve as an interesting introduction none the less.

So what did we find?  Pheasants and partridges have been reported as prey in some locations, and indeed a pheasant was reported brought in here.  But it is important to keep perspective in that this represents just over 1% of their observed diet.  Extrapolated to an average of 11 prey items per day as quoted by other studies this suggests up to 5 pheasants may have been taken during the entire nesting period.  So are the harriers bad for game birds here? We would suggest not - and that they are actually beneficial believe it or not.  In the same period 9 rats were observed brought in (extrapolated to 44 during nesting) and as substantial predators of eggs and nestlings the removal of 44 rats would we imagine reduce predation of ground nesting birds like pheasants and partridges.

The real losers were coots and moorhens with a likely 153 chicks taken from the surrounding wetlands, closely followed by 49 rabbits and 34 water voles during the season.  The completed chart shows the proportions here:
A few folk have asked if they'll return next year - that we don't know.  Successful birds do return to the same nest site; but this years circumstances were exceptional as poor weather had stunted oilseed rape and winter wheat they often nest in - so we can only hope:
Now another raptor - this time being a bit more controversial.  We've had a few photographs of great spotted woodpeckers harvesting insects from under the D res capping stones over the years - and it appears this female sparrowhawk had also made similar observations - thanks to Mal Jones and spotted by Mike Armitage:
More red in tooth and claw; stoat dispatching a rabbit in the car park last week - Roy L:
One burning question I am asked repeatedly is 'when are the belted galloway cattle returning?'.  I can confirm they certainly are and we are currently arranging their visit with Edward and Nicola Duggleby.  However last year they didn't come til late September and ran out of grazing after 6 weeks - so we're not in a rush.  We also hope to have the fencing around South Scrub completed by October too so as we can move the cattle straight from Hempholme to there in November.  At the moment the vegetation is so tall we would likely lose an elephant in the meadow! Our management is to mimic a traditional wet meadow with a summer hay cut and aftermath grazing - so contractors have been setting too where we've left off - to the indifference of the wildlife (Roy Vincent):
Grey heron and little egret (Roy V):
Along with greenshank:
Roy also snapped this green sandpiper on North Marsh:
South Marsh East has also been holding up to 5 snipe if you can find them - thanks to Roy L for this one:
They've been inhabiting the new drains we have excavated this summer amongst the tall vegetation:
The vegetation growth has been dramatic this summer in the drained marsh.  Originally we had toyed with the idea of draining the marsh for a while; but the willow growth has been prolific - with around 8 saplings every square foot.  If left it will turn to woodland - so we need to flood it again this winter and will be running it 'as normal' next year.  One problem is that the fox trench is silted beyond redemption - 'rare' nodding bur marigold (one of hundreds on the marsh this year) growing well on the fox proof barrier:
So we'll be toying with other protection measures on the gravel islands for next year. We've also been busy with the volunteers constructing new nesting islands in deeper water away from fox predation and will be doing as much as we can on the marsh before the rains come:
We also have a plan for keeping pike out the marsh so hopefully duck broods should be up for next year too.

So what else in amongst? Bird highlights have included;
Cetti's warbler on the 13th on SMW
Black necked grebes x 2 on O res until the 13th
Willow tit on the 10th
Osprey on the 9th, 15th, and 17th (showing well North Marsh hunting the river am)
Greenshank up to 2 daily between the 10th and15th
The first autumn ruff on the 11th with another on 13th and 14th
Green sandpiper daily
Whimbrel on the 14th
Little gull on the 13th by Mal:
And a leucistic pale billed herring gull by Tony McLean:
And great crested grebes building in numbers on the reservoirs like this juv by Maurice Dowson:
We've also been trialling a new method of wader counting; one that never sleeps or misses a shot - robobirder (or a trail camera on a scrape) a few snippets so far:
The biggest highlight though was caught by Maurice Dowson this morning though - banded demoiselle near the D res substation this morning.  Roughly the 13th for site and the first since 2006:
Some nice draggy's about now - common darter by Roy Vincent:
And by Maurice Dowson:
Southern hawker:
Some nice butterflies including a painted lady by Mal:
And thanks to Roy V for this of peacocks enjoying hemp agrimony:
Along with green veined white:
Some highlights from the pond dipping last week; water measurer:
And water scorpion:
And these fine beasts - a deceased male wood wasp or greater horntail:
And the alive female which is around 1.5" long!: