Wetland herons
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Herons and egrets stand or stride along the water’s edge, waiting patiently for a chance to catch a fish or frog with a lightning strike of the bill. Goliath Heron L: 152 cm (60") |WS: 185–230 cm (73–91") This enormous heron with a heavy, dagger-like bill, stands 1·5m (5ft) tall . Although superficially similar in coloration to Purple Heron, the Goliath Heron is twice the size, and has a ponderous, laboured flight on long, very broad, rounded wings . The plumage is rufous and grey with a characteristic white throat, and it has a distinctive black bill and legs . Immatures have rustier upperwings than the adult . The Goliath Heron hunts along the large waterways of the Kruger, where it is an uncommon but conspicuous resident . It has a distinct “kowoork” barking call that can be heard from up to 2km (1·2 miles) away . This species is a picky eater, and mainly hunts fish weighing more than 500g (1·1lb), stabbing them with open mandibles . Because it takes time to swallow such a large catch, it is vulnerable to the attempts of other birds to pilfer its prey, despite its size . Potential thieves include African Fish-Eagle, Yellowbilled Kite and Saddle-billed Stork . Wetland herons adult . The Goliath Heron hunts goliath heron purple heron grey heron 20 Purple Heron L: 85 cm (33") |WS: 120–150 cm Much smaller and shier than the similarly plumaged Goliath Heron, this relatively slim and delicate heron has a diagnostic black crown, black stripes on the sides of the rufous face, a slim yellow bill, and yellowish rather than black legs . Young birds are almost entirely pale rufous . The Purple Heron is a widespread but uncommon resident, preferring areas with reeds and rushes where it can hide and forage . It is a stalker and prefers to hunt at dawn and dusk from thick cover such as dense reeds, catching fishes, amphibians and insects . When surprised or threatened it will fly or adopt a ‘bittern-like’ posture, pointing its head skyward, to camouflage itself in the reeds . Grey Heron L: 97 cm (38") | WS: 155–195 cm (61–77") This is a large, pale and almost all-grey heron, entirely lacking the rufous hues of the much larger Goliath Heron and more slender Purple Heron . The adult has a distinct black eyebrow that extends behind the head as a fine plume, and a white face, head and foreneck . Juveniles are dingier and greyer on the head . The legs and bill are almost always greenish-yellow . In flight, the underwings are a uniform slate grey, and the upperwings two-toned grey and black . This common resident is frequently encountered on Kruger’s freshwater lakes, ponds and impoundments . BIRDS OF RIVERS AND WETLANDS 21 ...


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