The 2016 Emperor Dragonfly hatch at the kitchen garden pond is officially over. 51 individuals were either observed actually during emergence, or had left behind their empty larval cases (exuviae) as evidence. This is a record since records began, although as it stands this is the first recorded record. Phil the gardener predicted 50, clearly demonstrating the value of local wisdom. I'd predicted 100, betraying my own background in making television.
Of the 51 that hatched only 3 did so in daytime. Of that three, none waited for my dedicated week long filming stint. As such, I managed to capture exactly 0 minutes of daytime emergence. I did capture 3 post dawn take offs and got to attempt first aid on two who had got stuck (futile, not recommended). However, as an event at Tyntesfield it was a great success despite not firing any cannons. Dragonflies and the pond are now firmly on the map. I learnt a great deal and was able to pass on a great deal of learning to others. Overall, I rate it as my most successful failure yet.
For our last day, with just about all of the adult dragonflies departed, we concentrated on looking at some of the younger larvae now showing up in the pond. The larvae spend two years underwater, so now it's the one year olds (and perhaps a very few tardy twos) that remain. Pictures below of the larvae at different stages. The developing wing sheaths are visible, even on the smallest larva where they look like tiny black scales behind the head. They get bigger through each stage of growth. All measurements rough by my eye.
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Emperor Dragonfly larva (1). 1yr old (last summer's egg) Tiny <2cm.
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Emperor Dragonfly larva (1). 1yr old (last summer's egg) Tiny <2cm.
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Emperor Dragonfly larva (2). 1yr old. Small 2cm.
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Emperor Dragonfly larva (3). 1yr old Bigger Small 2.5cm.
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Emperor Dragonfly larva (4). 1yr old (last summer's egg) Medium 3cm.
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Emperor Dragonfly larva (4). 1yr old (last summer's egg) Medium 3cm. |
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Mayfly larva. A popular dragonfly snack. <1cm. |
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Emperor Dragonfly larva (5). Precocious 1 year old, or late developing 2 year old. I think this one had just moulted to the final larval size. 6cm.
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Emperor Dragonfly larva (5). Precocious 1 year old, or late developing 2 year old (next day from above). |