Some of the island's largest dragonflies are also its most elusive. Aeshnids, a family which includes an insect of avian proportions, spend the day on high boughs or low vegetation near forest streams, cloaked for the most part by dull brown or disruptive green patterns. Unless one encounters an ovipositing female, a typical encounter with an aeshnnid involves a palpable chill as a whirl of wings erupts from a thicket, a fleeting vision of a slim, stiff body, and if the beast is curious, a moment of unequal intimacy between distant phyla as it sizes up the source of its agitation before leaving it down for the count.
Corduliids also sport brilliant blue-green eyes and share with aeshnids the habit of dangling from foliage, as if the length and bulk of their abdomens preclude the ability to support themselves on horizontal perches and raise their tails to the sky in the manner of gomphids and overheated libellulids. But most hawkers, save Anax, which dwarves a diurnal skirmish of baskers, chasers and skimmers as it patrols the edges of marshy ponds, are creatures of twilight, phantoms of fleeting menace to the gnats, midges and mosquitoes that emerge at dusk and survive till daybreak.
Emeralds may hunt in the same zones, but are active when darners are not. Several, probably an assembly of Epophthalmia and Macromia, could be seen above a trail that runs by a swampy fringe, on a day when the sun had the strength to shove aside the clouds with enough regularity to lure the dragonflies from their shady lairs; through clearings between the trees they rose, banked, soared, glided and swooped at fellow cruisers, leaving the lowest reaches of the wetlands to their smaller, slower cousins – the grenadiers, sentinels and coraltails. Some commandeer a portion of the track, coursing through a natural arbour to eyeball bipedal intruders or intercept soft-bodied insects, which they quickly macerate into indefinable bits. They vanish the instant a shadow looms, as if the sudden dip in brightness poses an existential threat to their forays beyond the canopy, which they abandon for perches under cover. Retreating to leafy shrubs or jutting twigs, these big, bold hunters permit, in spots where they hang within reach, a measure of admiration for creatures that normally move with a speed that defies sight and the soft, spectral manœuvres of fugitive spirits.