It's been another week of avian arrivals and entomological emergence this week with the good weather bringing stuff out.

Bird wise, we have been treated to the first cuckoos singing on site, a brilliant grasshopper warbler singing persistently from the silt lagoon behind the Beach Hut, the first 2 common terns south of the new viewing screen and whitethroat singing from the boundary hedgerows. The avocets are still around and can sometimes be seen from the new viewing screen flying from the southern end of the site over Phase 2, numbers of sand martins are slowly building, marsh harrier has been see a couple of times in the last two weeks over Phases 1 and 2 and lapwings are displaying over the Phase 1 islands.

We now have 8 species of butterfly on the wing - peacock, small tortoiseshell, comma, red admiral, brimstone, small white and new this week, orange-tip and speckled wood. The cuckoo-flower - larval foodplant of the orange-tip, now in full bloom looks brilliant in among the cowslips.

I had the first Bibio marci, (St. Mark's Fly) on Tuesday - another real sign of spring. They are said to emerge on St. Mark's Day (25th April), hence their name, but they were four days early this year!

And the entomological highlight of this week has to be my first Cicindela campestris (green tiger beetle) of 2015 and one of my personal favourites. They look stunning with bright green colouration and yellow spots on the elytra (wing cases). They are a good size too, at an average of around 15-18mm in length. They can be seen running over bare or stony ground and I saw mine on the southern part of the Cromwell Trail, so keep your eyes open for them running over the path.

Cuckoo, now back on site. John Bridges (rspb-images.com)