Although the mornings feel autumnal (today was the first morning with a jacket over my t-shirt since June!), afternoons this week have been like mid-summer: warm sunshine that has encouraged the last of the butterflies, bees and dragonflies to take to the wing. Our weekly flying-insect survey recorded comma, speckled wood, common blue, small white and green-veined white on Friday, plus a probable hornet hoverfly, a third site record in the wake of two last summer.

An insect that is easier to spot are the caterpillars of alder sawfly. Like little snowflakes, these white, fluffy larvae are munching their way through the alder sapling leaves in the car park. They disguise themselves as bird droppings to avoid being eaten, though the white powder does eventually rub off, revealing a pale green body.

Bird of the week was the second pectoral sandpiper of the Autumn, found and identified by call (but not seen) by former warden Mike Duckham on Monday (12th) evening. It was seen on Tuesday morning, but not again. Thursday (15th) proved a good day for waders, with little stint, curlew sandpiper, grey plover, knot, greenshank, common sandpiper and 40 dunlins. Several of these remained to the weekend, with two bar-tailed godwits on Saturday (17th).

Our long-staying great white egret was joined by a second bird on Wednesday, so perhaps we've had two for a while, just not together? A spoonbill flew over the reserve on Wednesday (14th) and Thursday (15th), but headed upriver and wasn't seen to land. The flush of small fish into the estuary, featured in last week's blog, brought four Sandwich terns on Tuesday (13th) and 20 on Thursday (15th), plus 44 cormorants, a high count for the south side of the bridge. A guillemot was another unusual visitor to the estuary on Thursday, perhaps lost in the sea fog that enveloped the coast that day. Our long-staying garganey was seen on Wednesday (14th) and Saturday (17th), with a pintail and two choughs also recorded on Wednesday.

Summer migrant songbirds are feeding up before continuing their journey south. There were lots of blackcaps on the elderberries this morning, and earlier this week we've seen wheatears (five on Thursday, and singles daily since), redstart and white wagtail. Kingfishers have been spotted daily, with up to three present.

A yellowhammer was a great find last Sunday (11th), feeding on seeds in front of the Tal-y-fan Hide, with goldfinches and linnets. Sadly, they are all too rare a sight in this part of the county now.