United Kingdom
The complex geology of southern Britain is clear from the map. Chalk dominates much of the east of the country; it surrounds the Weald (the green area to the east) and the clay lands of the Thames Estuary and extends as far as the Isle of Purbeck. The red shapes show were I have worked. Some of my favourite species are included here.
The complex geology of southern Britain is clear from the map. Chalk dominates much of the east of the country; it surrounds the Weald (the green area to the east) and the clay lands of the Thames Estuary and extends as far as the Isle of Purbeck. The red shapes show were I have worked. Some of my favourite species are included here.
The Brilliant Emerald (Somatochlora metallica)
This dragonfly most typifies the Weald.There are records for this beautiful metallic green insect from elsewhere in Southern England but the Weald is its stronghold; It is particularly common in the lakes of the Forest ridges, particularly in the upland areas of Ashdown Forest; its overall Wealden range is shown as the red hatched area on the map (below) which also shows the rivers and floodplains.
This dragonfly most typifies the Weald.There are records for this beautiful metallic green insect from elsewhere in Southern England but the Weald is its stronghold; It is particularly common in the lakes of the Forest ridges, particularly in the upland areas of Ashdown Forest; its overall Wealden range is shown as the red hatched area on the map (below) which also shows the rivers and floodplains.
The Southern Damsel (Coenagrion mercuriale) and the Isle of Purbeck
This tiny damsel is a western Palearctic endemic globally listed as Near Threatened in the IUCN Red List and Endangered in several parts of its range. In UK the Isle of Purbeck is one of its key areas and it is not in a good situation.
Not in fact an island, Purbeck is a peninsula in the county of Dorset bordered by the English Channel to the south and east, where steep cliffs fall to the sea, by the marshy lands of the River Frome to the north and Poole Harbour to the east (Wikipedia). Historically this was an area dominated by mining particularly of Ball Clay, which is an important component of the ceramic industries. This industry was set in an essentially agricultural environment; livestock grazing, harvesting of the heath and the creation and abandonment of mines providing a constantly changing landscape. Coenagrion mercuriale would probably have flourished along the heathland streams with Ischnura pumilio common on the constantly changing pools. Today the remaining heathland landscape looks unchanged; however the mining has largely disappeared as has the grazing. Many of the streams and pools are overgrown to the detriment of both these local species. On the positive side much of the heathland is now in some form of conservation protection providing opportunities for management to maintain these species.
I have been studying C.mercuriale for many years in Purbeck. Up to 2006 there were five sites in Purbeck with significant populations. Today there is just one. The second most important site was clearly in decline in 2009 and there have been no records since. Four other sites have critically low populations. In summary, there was in 2015 only one site with a significant population thankfully it is well managed and in the hands of the National Trust.
A great deal more work is needed to arrest the loss of this vulnerable insect.
This tiny damsel is a western Palearctic endemic globally listed as Near Threatened in the IUCN Red List and Endangered in several parts of its range. In UK the Isle of Purbeck is one of its key areas and it is not in a good situation.
Not in fact an island, Purbeck is a peninsula in the county of Dorset bordered by the English Channel to the south and east, where steep cliffs fall to the sea, by the marshy lands of the River Frome to the north and Poole Harbour to the east (Wikipedia). Historically this was an area dominated by mining particularly of Ball Clay, which is an important component of the ceramic industries. This industry was set in an essentially agricultural environment; livestock grazing, harvesting of the heath and the creation and abandonment of mines providing a constantly changing landscape. Coenagrion mercuriale would probably have flourished along the heathland streams with Ischnura pumilio common on the constantly changing pools. Today the remaining heathland landscape looks unchanged; however the mining has largely disappeared as has the grazing. Many of the streams and pools are overgrown to the detriment of both these local species. On the positive side much of the heathland is now in some form of conservation protection providing opportunities for management to maintain these species.
I have been studying C.mercuriale for many years in Purbeck. Up to 2006 there were five sites in Purbeck with significant populations. Today there is just one. The second most important site was clearly in decline in 2009 and there have been no records since. Four other sites have critically low populations. In summary, there was in 2015 only one site with a significant population thankfully it is well managed and in the hands of the National Trust.
A great deal more work is needed to arrest the loss of this vulnerable insect.
...and what of The Scarce Bluetail (Ischnura pumilio)??
The beautiful aurantiaca female is shown here. This is a damselfly of new waters,it can even be found in tank tracks! In Spain where it is locally common it even breeds in temporary lakes that dry up in the summer most years. I used to know it in Dorset; whenever the RSPB created a new pond there it was. Ball clay mining meant that new excavations made for an I. pumilio paradise. Now such new pools are not being created and whither I.pumilio. I do not think that there have been any records for a number of years.
The beautiful aurantiaca female is shown here. This is a damselfly of new waters,it can even be found in tank tracks! In Spain where it is locally common it even breeds in temporary lakes that dry up in the summer most years. I used to know it in Dorset; whenever the RSPB created a new pond there it was. Ball clay mining meant that new excavations made for an I. pumilio paradise. Now such new pools are not being created and whither I.pumilio. I do not think that there have been any records for a number of years.
The Thames Estuary
I started visiting Hadleigh Park near Benfleet in 2007; it had a thriving population of The Scarce Emerald Damsel (Lestes dryas) which is locally common along the Estuary. I have been visiting regularly ever since and have witnessed its changing fortunes over the years. The added bonus is that I have found two species very new to Britain: the Southern Migrant Hawker (Aeshna affinis) and the Willow Emerald (Lestes viridis).
There will be a lot more on this locality and its dragonflies soon.
I started visiting Hadleigh Park near Benfleet in 2007; it had a thriving population of The Scarce Emerald Damsel (Lestes dryas) which is locally common along the Estuary. I have been visiting regularly ever since and have witnessed its changing fortunes over the years. The added bonus is that I have found two species very new to Britain: the Southern Migrant Hawker (Aeshna affinis) and the Willow Emerald (Lestes viridis).
There will be a lot more on this locality and its dragonflies soon.