, Asio capensis
, are generally nocturnal birds but they may also hunt on very overcast or misty days. The individual pictured here was laying in ambush just before sunrise. It shows the ear tufts in the centre of its forehead very clearly but these are often inconspicuous and may even appear to be absent.Large view
The Marsh Owl is locally common in much of southern Africa where it is resident but with some local movements as a result of changing availability of food. This bird prefers open country between the coastal marshes and the savannah, inland marshes, moors and even the highlands up to 3 000m. It prefers areas of short vegetation with occasional patches of longer grass and is sometimes seen near human habitation. It is not found in forested areas.
The Marsh Owl is an opportunistic hunter with a varied diet and equally varied hunting methods. It will use perches such as tree stumps or fence posts when they are available but is equally adept at quartering the ground at a height of a few metres or dropping abruptly on its prey or even pursuing prey on foot. Its diet includes a wide variety of mammals from very small voles to medium-sized animals like hares. Small rodents and small birds make up the major part of its diet, but it will also take bats, birds, amphibians, reptiles and invertebrates such as scorpions, locusts and beetles.
The main threats it faces are bush fires, floods and habitat degradation by overgrazing and by the use of pesticides. It is also susceptible to road traffic and entanglement in barbed wire. Some nests are lost to predators.
It is generally seen singly or in pairs although, outside the breeding season, it may be in larger groups. Favoured roosts during the daylight hours are in hollows in long grass or similar vegetation - at night it is likely to be seen perched on a fence post or similar vantage point, keeping watch for potential prey. It tends to be quite aggressive in defense of its nest, but may, if the occasion demands, feign injury to distract a potential enemy.
The Marsh Owl is both monogamous and highly terrirorial. Where there is a colony, each territory can be as much as two square kilometers, although in areas of dense population and abundant food they may be as close as 75m apart. The male advertises his claimed territory by circling above it with much wing-clapping and croaking. This is continued by the pair as a courtship ritual. A depression in the ground amongst tall grass or weeds is lined with dry leaves towards the end of the wet season to form a nest. Vegetation is often pulled over the top of it as a canopy and alongside as an entrance tunnel. Between two and six eggs are laid with three being average, at intervals of two days. The female commences incubation with the first egg. Incubation lasts for 27 – 28 days. The chicks open their eyes at about seven days and by ten days the facial disc is clearly visible. The young leave the nest and scatter into the vegetation from two weeks on. They make dancing motions and small calls to advertise their position to the adults, who bring them food. By 10 weeks they are fully feathered. Fledging commences at 29 - 35 days, but the young remain with their parents for some time before becoming totally independent.
It was first described by dr Andrew Smith in 1834.