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Although gardening for wildlife
is now most definitely a mainstream activity and what was once
seen as a rather quirky pastime is now a regular feature in
almost all gardening magazines and television programmes,
there is still a tendency for many of us to concentrate on
those creatures that we see as either beneficial to the
gardener (bees, ladybirds and slug devouring ground beetles
for instance), or those that are regarded as beautiful –
butterflies, blue tits or song thrushes. Many gardeners are
still very selective about the creatures they find in their
plot and that’s fine - even the smallest concession to
accommodating wildlife is worthwhile. But I believe that
wildlife gardening should be about much more than this. It
should embrace the idea that any area where we grow plants,
whether for food or for aesthetic reasons, has a life of its
own, much of which we know very little about. Every kind of
creature is likely to make a home in ‘your’ garden area and
every one of those creatures has a role to play in your garden
ecosystem.
For some gardeners dragonflies
and damselflies may well fall into the category of ‘not very
useful’ creatures, and indeed there are many people who are
positively afraid of these insects – they certainly do have a
rather fierce look about them. Their darting flight and
seemingly aggressive nature makes them appear dangerous and
possibly not the kind of wildlife we want to encourage! But a
closer look at these insects, their life cycles and habits
could convince you that there is more to the ‘Devil’s Darning
Needle’ as they were once known, than you previously
imagined. Furthermore they are predators of the first
magnitude and do perform a very useful role in the garden. By
learning a little more about them, we can hopefully appreciate
them as garden inhabitants of great beauty and grace.
Around forty species of these insects, which are members of
the order Odonata, breed in the UK and several more visit us
as migrants each year. Some species occur in specific
habitats such as boggy ponds in moorland locations, or in slow
flowing rivers. These species are unlikely to be attracted to
our garden ponds, but others, particularly those that
specialise in colonising new water, are likely to appear
quickly where a new aquatic habitat has been created, whether
in city or countryside.
Adult dragonflies and
damselflies spend time looking for new areas of water in which
to lay their eggs, searching these habitats out from high
above ground level. Their large compound eyes mean they have
excellent vision, both for locating their prey and for finding
new territory for egg laying. They are also equipped with
fierce jaws and are able to catch their prey with their legs,
carrying the unfortunate insect off to a favourite perch
before devouring it.
Both dragonflies and damselflies
use these same tactics to hunt and kill their prey, but
telling these two groups apart can be difficult. The general
idea that damselflies are the smaller of the two is not much
help to the amateur dragonfly watcher, and indeed is not
strictly correct. One useful identification pointer is
most damselfly species at rest will sit with their wings folded back
along their bodies, while dragonflies have their wings open at
right angles to their body. Identification of actual species
is difficult for most of us, not least because many species
are fast and furious flyers! Seeing one of these insects
close up and stationary is an unusual occurrence, and it is
worth using a small digital camera if you wish to get to know
this group of insects a little better. A really good identification guide (see
recommended books below) will aid rather than confuse
you. Important features to look out for are the colour of the
abdomen, thorax, eyes and legs, plus the patterns of the
veining on the wings. Another useful aid to identification,
as with butterflies, is timing and location, although the fact
that males, females and newly emerged adults of the same
species can all look very different throws a bit of confusion
into the mix! However, if you have mastered the
identification of butterflies, these seemingly bewildering
insects should not be too difficult. But most of us may
not care less about the finer details of identification –
often it is just enough to appreciate a beautiful creature in
the garden, and understand a little about its life cycle and
habits.
Attracting them and catering for
their needs provides enough satisfaction. We all know that
water is essential if you expect dragonflies and damselflies
to set up home and breed, but even if you have no water these insects are likely to
visit your garden to search for prey if there is a good
breeding pond somewhere nearby. Areas of long grass are often used for
hunting or ‘hawking’ for food, so if you are interested in
dragonflies but would prefer not to have a pond in your
garden, a meadow may well attract several different species. The
important factor is that prey should be available in the form
of small winged insects and if you are gardening organically
the presence of lots of juicy flies, wasps and occasional
butterflies is inevitable.
If you already have a pond you
may well have come across the fearsome looking dragonfly
larvae that lurk in the mud at the bottom. These remarkable
creatures may spend up to five years in this state depending
upon the species, although a year or two is more usual. The
larvae feed on a variety of pond creatures including tadpoles
and small fish, water snails and anything else they can get
their jaws around. When they have reached a suitable size and
conditions are warm enough, the larvae move to shallow water
to prepare for their final moult. Unlike butterflies and
moths they change directly from larvae to adult winged
insects, with no pupal stage in between. They climb out of
the water aided by the stems of plants such as rushes and
reeds, and shed their larval skin to reveal the beautiful
insect within. These young dragonflies or ‘tenerals’ are pale
in hue, their true colours appearing over the next few days as
they mature. Mating takes place on the wing and egg laying
females can often be seen dipping their abdomens into water as
the eggs are released.
Attracting dragonflies and
damselflies to your garden is relatively simple. Any
pond, well stocked with a good range of plants, especially oxygenators and emergent plants such as stout rushes and
reeds, will provide a good breeding ground for several
species. Some, including the huge Emperor
Dragonfly, prefers a large pond with deep water areas, but
smaller species including the Large Red Damselfly, one of our
commonest damselflies, will quickly set up home in a small new
garden pond. Often the first explorer to new territory is the
Broad Bodied Chaser. This lovely insect is a good species to
get to know. The ‘chasers’ are a group of dragonflies with,
as the name suggests, broad rather flat bodies, quite
unlike our common perception of the Devil’s Darning Needle’ or
‘Horse Stinger’ of country lore. The male’s body is pale blue
while the female is yellow. This species conveniently sits
around on a prominent perch, looking for prey and giving us
the opportunity to examine it at close quarters. Tall plants
such as purple loosestrife around a wildlife pond are
important for dragonflies as they make perfect perches for
this hunting behaviour. Another early coloniser of the garden
pond is the Southern Hawker. This is an insect with the more
’typical’ dragonfly shape – a long narrow body with bands of
colour. The males are striped with black and green while the
females are brown and green. This insect is quite large –
about 7 cms in length with a wingspan of 10 cms. It moves
quickly and can appear quite fearsome as it ‘hawks’ back and
forth across the garden looking for a juicy morsel.
There are many
more species that will make a home in your garden if there is
a suitable habitat and insect prey. Combine your pond with a
meadow area to provide the conditions these efficient
predators need and there is no doubt you will soon be
scratching your head as you try to tell your dragons from your
damsels!
Learn more…
The British Dragonfly Society
has a website at
www.british-dragonflies.org.uk
Useful books…
Field Guide
to the Dragonflies and Damselflies of Great Britain and
Ireland by Steve Brooks, Steve Cham and Richard Lewington
Britain’s Dragonflies by Dave
Smallshire and Andy Swalsh published by Wildguides
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