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conservation is our evidence about the value of
flooded sand-and-gravel pits as dragonfly habitats,
Fully eighteen out of our twenty-four species have
been recorded either breeding in, or hawking
for prey in the vicinity of such pits. In my
view, the growing practice of using such pits
for tipping, reclaiming them for development, or
use for water sports should be strongly questioned
The slower-moving reaches of rivers and streams
also have great importance as dragonfly habitats.
The greatest threats here are, again, fertiliser
run-off via drainage channels, when adjacent
water-meadows are converted to arable, combined
with over-zealous and insensitive management of
bank-side vegetation, large-scale dredging, river-
straightening, and so on. Finally, the coastal
and estuarine marshes, with their often brackish
'borrow dykes' and ditches are a distinctive
Essex habitat. They support rather few species
of dragonflies, but these few are often of the
greatest significance conservation-wise. These
marshes are important as the main breeding sites
of our great rarity, Lestes dryas, and also
support several other local species, such as
Lestes sponsa and Libellula quadrimaculata.
Two other species have an interesting and
puzzling association with these coastal ditches.
They are the Migrant Hawker (Aeshna mixta) and
the Ruddy Sympetrum (Sympetrum sanguineum).
A. mixta was once considered a rarity, but is
now widespread and common, particularly in Essex.
S. sanguineum, however, is declining nationally,
but remains well established, though rather local,
in Essex. Both species are migratory so that
reports of their presence in an area do not
necessarily imply a local breeding site. Clear
evidence of breeding activity (mating, egg-
laying, or emergence) is therefore urgently needed
if we are to fully understand the status of
these species in Essex. So far, there are
breeding records of both species from our coastal