Purbeck mason wasp

In the UK the rare Purbeck mason wasp (Pseudepipona herrichii) is found only in the Isle of Purbeck, Dorset.

The female excavates a nest burrow in bare ground on heathland and later seals it with moistened clay.

Wasp with excavated soil

Purbeck mason wasp (Pseudepipona herrichii) excavating nest burrow on heathland. Dorset, UK.

She stocks her burrow with the larvae of a small moth which feeds mainly on bell heather.

Purbeck mason wasp: prey

Purbeck mason wasp (Pseudepipona herrichii) with Acleris hyemana moth larva prey at nest burrow entrance. Dorset, UK.

The adults chew distinctive holes in the heather flowers to obtain nectar which their short tongues could not otherwise reach.

Wasp drinking from heather

Purbeck mason wasp male nectaring on bell heather. Dorset, UK.

The Purbeck mason wasp is thought to rely solely on the larvae of Acleris hyemna, but in 2017 I photographed this female provisioning her nest with what appears to be the moth Acleris notana.

Purbeck mason wasp: prey

Purbeck mason wasp (Pseudepipona herrichii) with moth larva prey (Acleris notana?) at nest burrow entrance. Dorset, UK.

One small victory for citizen science?

Related links

Digger Wasp Hostage

Sand digger wasp with caterpillar

The sand digger wasp (Ammophila sabulosa) paralyses its prey

We encountered another variety of sand digger wasp on the heath recently – this time Ammophila sabulosa, which uses caterpillars to feed its larvae.

Sand digger wasp with caterpillar prey

Sand digger wasps’ prey may be 10 times heavier than the wasp itself

Similarly to the spider-hunting wasp (Anoplius viaticus) it paralyses its victim with venom from its sting and buries it in a nest burrow. The caterpillar remains paralysed until the wasp larvae hatch out and eat it alive!

Sand digger wasp excavating nest burrow

Female sand digger wasps excavate a short burrow in sand

The entire nest cycle from site location, through excavation and provisioning, to finally sealing the burrow, takes 8-10 hours to complete.

Many wasps have ingenious parasitic strategies, as these earlier blog posts illustrate:

Related links:

Dartford Warbler Winter

Dartford Warbler Snow Drift

Dartford warbler (Sylvia undata) foraging on snow covered heathland

In the severe winter of 1962/63 the Dartford warbler (Sylvia undata) was almost wiped out in Britain. The national population dropped to just 10 pairs.

But in good breeding seasons, and with suitable habitat, its numbers are capable of bouncing back, thanks to repeated nesting and high survival rates among its offspring.

On the Surrey lowland heaths Dartfords have been doing well, re-colonising Thursley Common last year for the first time since a devastating fire in 2006.

During the recent freezing winter weather I photographed this Dartford warbler foraging in the snow on Chobham Common:

Dartford Snow Flurry

Dartford Snow Dipper

Related Links: