Black-Tailed Skimmer (Orthetrum cancellatum)
I always think of these as the mud worshippers, they like nothing better than resting on bear mud and heating themselves up.
Males have a blue abdomen.
Females have a yellow abdomen with black markings.
Immature, they are both yellow and very similar.
The main confusion will be with the Scarce Chaser and Keeled Skimmer.

Male
Male
Male (Getting Blue Colouration)
Male (Getting Blue Colouration)
Male (Getting Blue Colouration)
Male (Getting Blue Colouration)
Male (Very Start Of Turning Blue)
Male (Very Start Of Turning Blue)
Male (Teneral / Newly Emerged)
Male (Teneral / Newly Emerged)
Male (Newly Emerged) / Female Flying
Male (Newly Emerged) / Female Flying
Male (With Bent Abdomen)
Male (With Bent Abdomen)
Male (With Bent Abdomen)
Male (With Bent Abdomen)
Male (With Bent Abdomen) - A Week Later
Male (With Bent Abdomen) - A Week Later
Male (With Bent Abdomen) - A Week Later
Male (With Bent Abdomen) - A Week Later
Female
Female
Female
Female
Female (Teneral / Newly Emerged) - Wings Still Together
Female (Teneral / Newly Emerged) - Wings Still Together
Female (Teneral / Newly Emerged) - Just Opened Wings
Female (Teneral / Newly Emerged) - Just Opened Wings
Female (Teneral / Newly Emerged)
Female (Teneral / Newly Emerged)
Female (Teneral / Newly Emerged)
Female (Teneral / Newly Emerged)
Female (Immature)
Female (Immature)
Female (Mature)
Female (Mature)
Female (Mature)
Female (Mature)
Female (Elderly)
Female (Elderly)
Mating
Mating
Want to See 
Widespread over Somerset, but the Levels tend to be the best spot for them.
Likes rhynes, reedbeds, ponds and slow moving rivers.

Especially Good
SWT Westhay (End Of May / June)
RSPB Greylake (End Of May / June)
Priddy Pools (Mendips) (June / July)

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