Monday 27 August 2018

Grimsbury Reservoir: juvenile Black Tern

Yesterday a juvenile Black Tern graced Grimsbury Reservoir in the latter part of the afternoon and early evening.  Thanks to the persistence of finder Colin Wilkinson, making his second patch visit of the day, I was able to spend about an hour watching this ever-so graceful bird swooping across the reservoir.  On one occasion it rose up into the air with a cluster of alarmed Sand Martins and House Martins - a Hobby was on the prowl.  It continued feeding away until I left but was gone by this morning.  A male Redstart also showed well, perched on the barbed wire fence along the edge of the cattle grazed field and feeding along a sheltered stretch of hedge.

Black Tern, juvenile
Great-spotted Woodpecker, male, in a dead Scots Pine at the entrance to the reservoir this morning
I've been spending a it more time at Boddington Reservoir recently, and as water levels in this canal-feeder reservoir have dropped, it has become more attractive to Little Egrets (up to 4) and Common Sandpipers (up to six) in particular.  Willow Tits have also been quite vocal and I have seen at least three birds in the vicinity of the boat club HQ.
Little Egret, Boddington Reservoir
Up at Tadmarton Heath BOS nature reserve this morning, it was interesting to see that the wild bird food crop, that had struggled to grow at all over the dry summer, has suddenly started to flourish, and Corn Marigolds have appeared again.  This years crop of Blackberries is also very notable for the size and quantity of the berries!  A few birds were taking advantage of the abundance of food, especially Bullfinches (including just-fledged chicks) and Whitethroats.
Corn Marigold

It has also be great to see quite a few pairs of Little Grebes rearing young on local lakes and pools, including three pairs using the "Borrow Pit" next to the Banbury flood defence.  This photo was taken a couple of weeks back.
Little Grebe adult and young





Sunday 5 August 2018

Upper Wardington: Butterfly snowstorm

Whilst out for a run on Friday I was stopped in my tracks by a huge gathering of white butterflies along the edge of a field of Oilseed Rape.  Quite a spectacle - there must have been hundreds if not thousands of butterflies dancing around the field margin, together with some considerable numbers across the field itself.  I returned this afternoon armed with camera to investigate further and take some photos.
This turned out to be a good example of how nature can suddenly become abundant, even alongside intensive arable farming.  In this case, the presence of flowers of the cabbage family (presumably sown deliberately) and a liberal scattering of Phacelia (also known as the bee flower) plants had created very attractive conditions for white butterflies to nectar and egg lay, and great opportunities for bees to feed and gather pollen.  Most of the butterflies were Small Whites, but most of the eggs and caterpillars present on the plants were of the Large White.  Some of the caterpillars were being eaten alive by parasitic wasp larvae.  I also spotted a single, well worn, Green-veined White.



Small White
The field margin and associated white butterfly "snowstorm"
Large White eggs
Large White caterpillars - a parasitic wasp has laid its eggs in the caterpillar and they have been eaten alive! 

Phacelia and bee
First thing in the morning a trip down to Bicester Wetland Reserve was very enjoyable, with great views of Greenshank striding across the muddy pools, with beautiful reflections.  Green Sandpipers, Snipe and Water Rails were also showing well.  Later, in the afternoon, Alan Peters found that the Greenshanks had increased to three and Green Sandpipers to 13!

Green Sandpiper
Greenshank



Finally, it was great to catch-up, at long last, with close views of Brown Hairstreak butterflies at Otmoor on Saturday morning.  Especially as I managed to walk past a female sitting right next to the path!
Female Brown Hairstreak
Male Brown Hairstreak looking down from a favoured spot on an Ash leaf.