visits have been made to the Chelmer/Blackwater site, Langenhoe Marsh, and other
potential sites for this species. These searches (as well as E P. Ryan's in Epping Forest)
were without success until 28.5.1985, when K. M. Rowland and I confirmed the
continued presence of the species on Langenhoe Marsh. Two males were observed for
some time, hawking along adjacent sections of a shallow borrow dyke which was almost
choked with Sea Club-rush. The flight was very swift, and low down, just above, or even
below the tips of the rushes, with rapid direction-changes that deceived the eye. The
dragonfly appeared much smaller and far less conspicuous than I had been led to
expect from text-book illustrations. Flight was abandoned immediately full sunshine
was lost. In fact, the insect seems even to anticipate the obscuring of the sun by
advancing cloud, and simply disappears into dense beds of Sea Club-rush. If one takes
these features of appearance and behaviour together with its short, early flight-period it
seems readily understandable that it may have been overlooked even where still present
at a site. Another sighting, this time of one male, at the same spot was made by A. J. Wake
and myself on 18.6.1985, and on 26.5.1986 I was able to observe four or more individuals
of the species at the same site. Aerial mating was observed, and a 'solo' female was seen
laying eggs in an overgrown dyke. It now seems to me quite possible that.B. pratense may
still be present at other Essex sites. The Chelmer/Blackwater is worth continued
investigation, and remaining areas of coastal and estuarine grazing marsh (such as Old
Hall and Brightlingsea Marshes) should be searched for it. Pending further
investigation, however, it should continue to be regarded as our rarest breeding species,
and every care should be taken of its remaining habitat. It should go without saying that
on no account should specimens be collected.
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