Black Darter

Sympetrum danae
 
 

This tiny late summer darter is consistently the last of the Gateshead resident 16 to be sighted, usually not being recorded 'til late Aug/early Sept (mostly due to our awful late summer weather).
Not abundant anywhere, the boggy ponds at Kibblesworth, Burdon Moor and Stargate are the best places to look for them. Kibblesworth and Burdon Moor are ideal breeding sites, and though the boggy pond at Stargate looks good, there's no proof of breeding here as only one or two mature males are ever seen annually, perhaps just wanderers as they are very much a wandering species, with individuals even recorded at Far Pasture on a couple of occasions.


Two views of a mature male Black Darter in his prime, signified by the
bright yellow markings on the thorax and abdomen
The mature male Black Darter is a beautiful little darter and unmistakeable, being the tiniest of dragonflies and completely black apart from a few yellow markings on the face, thorax and base abdomen sides, and on top of the back end of the abdomen.
Immatures, (as in most darters) are predominantly yellow and aren't easily encountered.  
 
 
This more mature specimen has lost the bright yellow markings on the
abdomen, now covered by a grey pruinescence.


Males are non-territorial. Their flights are usually brief, and they are mostly
found perched on stems of marginal vegetation, or basking on rocks, bare
ground or  even wooden benches (at Cragside especially) 
Females look much like other darter females when viewed from the top, but a diagnostic feature is the black triangle at the front of the thorax.

Even on this recently emerged specimen, the black triangle is
visible on the thorax just below the head. 
Viewed from the side the lower half of the abdomen is completely black, differentiating from other darter females, as can be seen on this mature female (below).



The colouring on this recently emerged female is only slightly
paler than when mature, but the all white pterostigma
are a giveaway to its age.
Unlike other darters, mature females of this species stay hidden in thick cover for most of the day waiting for a male to search them out (this also explains why females are difficult to find for an observer).




In this way pairs are usually formed away from water and the tandem pair will go to the breeding site for ovipositing.
 
Unsuccessful males go to the ponds early afternoon to await any unpaired females, which will fly in at speed ensuring a chase involving several males will ensue, with the fastest winning the prize.
  

Note the male has jet black eyes, whereas the female are a standard
darter brown and green.

The pair will oviposit in tandem for a while, depending on numbers of males present, but the female usually finishes alone, and will hide in dense cover to avoid being seen by any single males on the lookout, resuming ovipositing in late afternoon when the males are more interested in food than sex.
Eggs lie dormant until the following spring, when the larvae hatch and develop over a two month period to emerge in July. 
 

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