Wildlife Notes for Great Ovens Heath by John Wright - July

After a holiday break, I was keen to see what was new on Great Ovens and on 8th July a walk soon revealed the developing cloak of purples and yellows that make the heath so spectacular in summer. The bell heath and cross-leaved heath, which had been flowering for some time, were joined by thin spikes of heather (often called ling) and also by the much more impressive spikes of dorset heath, our County flower, in one restricted area of the reserve. This nationally rare species is confined to Dorset and Cornwall.

Dorset Heath

Dorset Heath

Photograph : John Wright

The yellow colour is, of course, provided by gorse but not the large winter-flowering species which continues to bloom into late spring. In July two entirely
separate species of gorse start to flower. The diminutive dwarf gorse (furze) is common on Great Ovens, but the somewhat larger and more robust western gorse also occurs.These two species continue to flower into late autumn, by which time the larger european gorse is in flower again. Hence the expression 'when gorse is out of bloom, kissing's out of season!'.


 Dwarf Gorse

Dwarf Gorse

Photograph: John Wright

Whereas the summer generation of silver-studded blues was almost over, small heath butterflies were still abundant and in areas of long grass, marbled
white butterflies together with small and large skipper butterfies were active when the sun came out.


 

Marbled White

Marbled White

Photograph: John Wright

On the firebreak adjoining the B3075, I disturbed a butterfly which is very characteristic of heathland in late summer - the grayling. This butterfly has excellent camourflage and, when disturbed, normally flies ahead for a few feet before landing on the ground, tucking the forewing with an eyespot behind the rear wing and promptly diasppearing into the background before being disturbed once again.

Grayling

Grayling

Photograph: Ken Dolbear

The same firebreak is also yielding somew interesting plants associated with dry sandy locations, such as sheepsbit and blue fleabane and in damper shaded areas the attractive flowers of Slender St John's Wort.

Slender St John's Wort

Slender St John's Wort

Photograph: John Wright

On subsequent visits nearer the middle of the month, a noisy party of stonechats indicated that they had successfully fledged a second brood for the year. A raven flew over, producing that characteristic low 'pronk' call and I realised that this was the first I had heard over the heath this year. No doubt I will hear more as vocal parties or pairs pass over during the autumn and into the winter. Although the dartford warblers on the heath seem much less demonstrative than the stonechats, nevertheless, I had views and heard them singing within the sand quarry on a couple of occasions.

Raven

Raven

Photograph: John Wright

I also saw and managed to photograph one of the later emerging damselflies - the emerald damselfly - on the sand quarry pond. Unlike other damselflies which normally close their wings over their back, this one holds its wings out in a characteristic fashion. The metallic colouration is quite striking.

Emerald Damselfly

Emerald Damselfly

Photograph: John Wright

On the 21st July, although it was overcast, a blackcap was singing from thick cover as I returned to the heath and a few silver-studded blue butterflies were still on the wing at the southern end of the reserve. Unexpectedly, I flushed a nightjar sitting on a conifer stump as I made my way through the sand quarry and the large open pond attracted the first common darter dragonfly of the season. If conditions stay mild, these dragonflies can be seen well into October and November.

Common Darter

Common Darter

Photograph: Ken Dolbear

A couple of days later I saw my first male brimstone butterfly of the summer near the alder buckthorn bushes - perhaps the progeny of one of the female brimstone butterflies seen laying eggs on these bushes back in late April. Further along the track I noticed one of the most spectacular and easily identified caterpillars you will see on heathland - an emperor moth caterpillar. The large moths which are on the wing in spring, but rarely seen, are the only British species in the family which includes the silk moths.

Emperor moth caterpillar

Emperor moth caterpillar

Photograph: John Wright

As the end of the month approached, and after some rain, more interesting plants started to flower on damper parts of the firebreak by the B3075, including corn mint, field woundwort and sharp-leaved fluellen, with its small twin-coloured snapdragon-like flowers.

Sharp Leaved Fluellen

Sharp-leaved Fluellen

Photograph: John Wright

Finally, as the month ended, the sun shone once again and a variety of butterflies appeared including silver-studded blue, small copper, speckled wood, small heath, gatekeeper, meadow brown, small white, marbled white and grayling. A diversion to the sand quarry revealed lots of emerald damselflies and also a couple of black darters - the smallest British dragonfly.

Black Darter

Black Darter

Photograph: John Wright