Wildlife Notes for Great Ovens Heath by John Wright - May

May
There is always a lot to see on the heath in May, but the exceptionally warm weather this spring has meant that many plants have flowered early and both butterflies and dragonflies are appearing ahead of schedule. Sunshine on the 4th encouraged a song thrush to sing, presumably to entice a female to have a second brood with him. The warmth also encouraged small copper and red admiral butterflies to bask while the brimstone butterfly eggs seen last month had hatched and 1cm long caterpillars were munching chunks out of the alder buckthorn leaves.
 
A few days later some bell heather had started flowering, a family of long-tailed tits were calling to each other as they made their way through the tangle of gorse bushes and a female roe deer put in a brief appearance from the relative safety of the sand quarry. At the small vegetated pond, large red damselflies were joined by an azure damselfly and three downy emerald dragonflies. Two days later I was pleased to see a green hairstreak flying near gorse, our only butterfly with bright emerald green wings.

Green Hairstreak

Green Hairstreak

Photograph: John Wright

Before the middle of the month it was obvious from the commotion that two or three pairs of stonechats were feeding fledglings but the dartford warblers, although singing on occasions, were much more secretive. A large white butterfly was added to the butterfly tally, broad-bodied and 4-spot chasers plus downy emerald dragonflies were becoming regulars on the small vegetated pond and a raft spider was seen hunting over a damp mossy patch by the water’s edge. Tadpoles, most likely hatched from toad spawn, were seen in very shallow water held on the upper surface of water lily leaves, giving them some refuge from the goldfish patrolling below!

Broad-bodied Chaser

Broad-bodied Chaser

Photograph: Ken Dolbear

Raft Spider

Raft spider

Photograph: John Wright
 
By May 19th, with bright sunshine still the norm, a black-tailed skimmer dragonfly was seen resting some considerable distance from where it emerged from the water. This is normal and all dragonflies and damselflies stay clear of water for a week or so after emergence in order to harden their bodies and become mature before returning to freshwater and engaging in territorial disputes with their kind. The small vegetated pond still had some of the early emerging dragonflies patrolling but a small grass snake was also seen heading for the water, where tadpoles etc could be on the menu. In a nearby conifer where a nest-box had been attached to the trunk, nestling great tits made it clear that they were waiting to be fed.  
 
On the same day, one of the cuckoos heard with such regularity in Morden Bog spent a while on Great Ovens Heath, calling from a dead maritime pine tree on the open heathland. A pair of agitated tree pipits mobbed it, to be joined by a male chaffinch and then a swallow, which flew round the tree on numerous occasions to little effect. Eventually all the birds gave up their attempts to see off the cuckoo which remained in the tree, repeating its familiar song.
 
My final visit for the month on 25th May produced blue-tailed damselflies on both the vegetated pond and the sand quarry pond, where the cultivated lilies were also starting to come into bloom. As on my previous visit, a small heath butterfly was spotted but to my surprise and delight I also saw three male silver-studded blue butterflies on the wing. This heathland specialist butterfly, one of the gems of the Dorset heaths, normally appears in early June after both the caterpillar and chrysalis stages have received careful attention and protection by black ants.

Silver-studded Blue

Silver-studded Blue

Photograph: Ken Dolbear