Tag Archives: reproductive life cycle

Home grown dragons

One end of my front garden is curved and tapers to a point and was pretty much dead space, so last year I decided that I’d turn it into my own tiny nature reserve and make a pond. The street side of the garden is lined with beech hedge and the open end is bound by a hazel tree which I planted there 5 or 6 years ago, so it is an enclosed space which I hope will remain fairly undisturbed, apart from my forays to photograph the wildlife that takes up residence.

In order to try to maximise the wildlife potential I followed all the instructions on how to create a wildlife pond, so it’s around 30cm deep (which is enough to prevent the bottom from freezing even during the coldest UK winter) and was seeded with plant life and minibeasts from my friends pond, and there are no non-native species and no fish. The water went into it in February this year from my water butt (tap water contains chemicals which are not good for a balanced wildlife pond) and it’s remarkable how rapidly nature has taken hold. As well as all the beasts added by me which seeming to be flourishing, it has been discovered by various species of dragonfly, butterfly and hoverfly, and I put twenty common frog tadpoles in from another friend’s pond, of which at least one reached adulthood.

Common darter female (Sympetrum striolatum) perched on an iris leaf

In the corner of the garden where the pond is I’ve let the grass and wild flowers grow and I mow a path all the way round, so I can view it from all angles, and in one corner a small patch of stinging nettles is allowed to grow unhindered. In this way I’m hoping that eventually the grassy area will reach a balance with local wild flowers and provide a suitable habitat for a few more insect species. As well as the ubiquitous white butterflies, peacocks, and other regular garden butterflies visiting the garden, since the completion of the pond I’ve also added gatekeeper and speckled wood to my garden species list.

Common darter male drawing breath after a hard days mating

Apart from the introduced tadpoles, the most interesting visitors to my little zoo have been the dragons, of which I’ve seen at least 3 species of damsel, one darter and one hawker species, all either settled around the pond or hunting over it. Of these, the most notable have been the common darter which are very common in my part of the world, and are often very easy to photograph, and consequently the most frequent species shown here in my posts. But I think they’re incredibly photogenic! And this year in the garden I’ve managed to capture several aspects of their reproductive life cycle.

Common darter tandem pair

This pair, in the midst of copulation, were being constantly harassed by a lone male which had taken up defensive positions on the pond and was defending it vigorously. But they were not to be deterred and completed copulation and began ovipositing in the pond despite the unwanted attentions of the loner.

The male common darter has primary and secondary genitalia, the primary genitalia, located on the last abdominal segment, produce the sperm which he transfers to the secondary genitalia on abdominal segment 2 (counting along from the thorax), which contains the penis with which he inseminates the female. Transfer of sperm is done prior to clasping a mate with the anal appendages or ‘claspers’ at the ‘pronotum‘ (a plate of the exoskeleton at the back of her head) in the case of damselfies (Zygoptera), or by the head in the case of the Anisopteran dragons. She then attaches her genitalia to the sperm-containing secondary genitalia of the male and fertilisation ensues.

The tandem pair, now fertilised, looking for places to oviposit

Once the female had been fertilised, they flew around the pond and when they had identified a suitable location the female swung her abdomen downwards to eject an egg into the water. Some species of dragonfly search for specific locations underwater, such as the underside of leaves or within the stems of water plants, to lay their eggs, but the common darters were placing them directly into the water. Consequently they darted swiftly to and fro over the pond and the ovipositing movement was extremely rapid, making photographing the event a challenging task, but I managed one half decent shot:

The next chapter in this story will be when the eggs hatch to release the larvae into the pond, which happens 2-5 weeks after laying the eggs. Dragonfly larvae are voracious predators but there should be sufficient other insect life in the pond to keep them sated, and if I can catch one I’ll post the pictures later. And hopefully I can pphotograph one as it emerges from the water and metamorphoses into the adult dragon, which should happen next year if they survive.

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