Our Island Resident Species-Dragonflies(3).

The Keeled Skimmer could be considered a surprise resident on the Isle of Wight. The species is found in acidic wet heathland containing runnels and streams, not the habitat that you would associate with the Island. However on our  south-west coastal cliffs where the sandstone and clay are always on the move due to erosion, suitable habitat has been created on the landslip. Here small pools form  with emergent reeds and in a couple of areas along the coast this skimmer has made it home.

 

A common skimmer mainly found at any pond with bare exposed banks is the Black-tailed Skimmer. The males like to perch horizontally on bare ground,mud,stones and dead wood.

   

Back on the Landslip.

Despite a brisk easterly wind the sun was shining yesterday and there was autumn warmth in sheltered spots.At several ponds on the landslip at Compton Chine the dragonfly activity remains high with all the species encountered a few days ago  still evident.However I was very pleased to observe a female Emperor majestically cruising around  the largest pond looking for places to lay her eggs.Quite late in the season to see this particular species on the wing.

Landslip Ponds.

On the Islands' south west coast the cliffs are constantly on the move due to coastal erosion.The soft sandstone is weathered by wind,rain and sea to form scattered small ponds on these plateaus of landslip.These pools and ponds are a magnet for migrating dragonflies from the continent and there is always a chance to see a special arrival here.Today in warm sunshine several resident dragonflies were seen on and around these pools.Common Darters seemed to be the main species along with several Migrant Hawkers,although it was good to see that the Common Blue Damselfly is still here.Several males were seen patrolling a small pond together with females.I must say  it was the first time that I have witnessed the sight of a seemingly expired female floating on the water only to be plucked up by a male Common Blue and taken to the bank of the pond.There the male expected to mate but due to her condition it seemed to be a forlorn hope.

This Year's Top Highlight.

The 2014 season has seen a succession of  highlights with visits to the only remaining colony of Keeled Skimmers,Orthetrum coerulescens, on the Isle of Wight,to my first ever look at the Small Skimmer,Orthetrum taenioaltum,on the island of Rhodes.

Ferocious winter gales and heavy rain caused massive erosion of the coastal cliffs where the Keeled Skimmer is found here, in acidic pools on the cliff landslips.Hopefully as new pools are created their numbers will increase.

Another fantastic discovery was the sight of numerous male Red-veined Darters on territory at a local reservoir. These colourful darters are reported from time to time in singles but double figure numbers are quite unusual and exciting particularly on the Isle of Wight.

However the real highlight of this past season for me are the encounters with the Scarce Chaser. The odd individual has been noted since 2008 on the Island but this year several were seen at suitable breeding locations.Both these sites are in the south east of the Island,one in water meadows on a small, muddy slow  flowing river. and also at  mature fishing lakes surrounded by dense emergent marginal vegetation.

Males on territory and females were present at both sites.

The Scarce Chaser,Libellula fulva,is a 'Red Data' species and along with several other species they are considered as 'near threatened'.Therefore they and their habitats are protected by law in the UK.

Keeled Skimmers at Whale Chine

The south-west coast of the Isle of Wight suffers from  regular coastal erosion.This landslip of the sandstone cliffs creates ideal conditions for the Keeled Skimmer.On these areas of landslip, draining water forms boggy pools allowing the skimmer to survive and complete its life cycle.

Whale Chine is among several sites along this stretch of coast where this dragonfly can breed and July is normally the best time to see them.

Mature males are mainly blue whereas immature males are similar to the golden-yellow colour of the females.