Pondering 🤔

So! Four months in and no sign of damselflies or dragonflies.

I have to ask myself the question “Why?”

To answer that I’ll have to consider the following points.

• Location
• Sunlight
• Temperature
• Wind
• Water quality 
• Water depth
• Water movement
• The food chain
• Predators 
• Emergent plants 
• Pesticides.

The pond is situated at the bottom of the garden, near the house.

It is a sunny spot in the morning, but shady during the afternoon and evening.

It is protected from the wind by a high boundary wall, tall Aucuba Japonica shrubs, as well as the house. Heat is retained by the concrete patio slabs and surrounding walls.

So that covers the first four points.

The water quality is good, the water being clear and no signs of any blanket weed or algae.

The water depth is about 340mm. I know that some dragonfly species prefer at least 600mm but other species prefer shallower water. So this point is covered for some.Maybe the aeration, which causes water movement, deters them. I’ll temporarily switch the pump off to see whether there is a difference at the risk of algae forming. Perhaps I’ll have to turn it on momentarily periodically.

The pond is full of “Wrigglers”, blood worms, and other minute insect life. Hoverflies defend the air space above.

The water is aerated (oxygenated) and its movement attracts more insects to the food chain.

There are no predators within the pond as I don’t keep fish. However there has been the odd sighting of a toad and frog elsewhere in the garden. The pond was created after their breeding season, so there was never any hungry tadpoles.

The pond is bounded by the Aucuba which is at least 2m high and receives some sunlight.

There are emergent plants within the pond, such as Iris versicolor, Mares-tails, Pickerel and Typha. (The latter two are 600mm in height now) So there would be support for the larvae to emerge and metamorphasize into adults, a place to dry and inflate their wings before bidding us adieu.

The final point is easily covered as we don’t use pesticides in our garden and there is no opportunity for run off into the pond either.

The frustrating thing is that this time last year before the pond was built a damselfly was sighted on the Aucuba Japonica.

Beautiful Demoiselle (Calopteryx Virgo)

A Southern Hawker dragonfly was seen sunning itself on the 

Tree Fern at the top of the garden.

Southern Hawker (Aeshna cyanea)

Furthermore, today, Mrs S saw an unidentified dragonfly whilst working at the top of garden by her greenhouse. It is the hottest part of our garden.

So what conclusion can I now draw?

It is either likely to be a lack of sufficient sunlight or the water depth.

I cannot do anything about this, if indeed these are the salient factors.

However, it is still a healthy and viable pond nonetheless and who knows what the future holds.