The elusive White-backed Night Heron
February 27, 2020/by EcoTraining Pty Ltd
The white-backed night heron is an elusive and rather poorly known species of crepuscular piscivore. A relative of the much more common black-crowned night heron, this secretive and shy inhabitant of slow-flowing rivers and dams are generally regarded as rare throughout a rather wide distribution. They can be seen from the east cape of South Africa along the Indian coastal belt through to the Lowveld and into parts of Southern and central Africa.
But they can only be spotted in their suitable habitat which makes finding them for your life list that much trickier.
Difference between the White-backed and Black-crowned Night Herons
The species stronghold is undoubtedly the Okavango Delta where local mokoro based excursions from many lodges in the area offer a good chance of connecting with this sought after skulker. Birds are most often seen when flushed from bank waterside vegetation where they roost in the deepest shade during the daylight hours. They are generally active from early evening into the night before flying back to their roost sites as dawn approaches.
Their hunting methods
White-backed Night Herons (Gorsachius leuconotus) as with most herons are opportunistic feeders with fish, arthropods, frogs and freshwater crabs comprising most of its diet. Some of their prey will simply be seized because it is available. A strong spear-shaped bill is used to spear passing prey at such speeds that the prey passing won’t know what hit them.
Underwater prey is waited for patiently, usually from vegetation overhanging the surface of the water or from a waded position just out from the bank. These birds can sit motionless for long periods of time until the opportunity arises. Like all herons, they possess specialised neck vertebrae. The neck is able to kink in an S-shape, due to the modified shape of the cervical vertebrae. This acts as a coil spring which gives their hefty bill incredible speed when the head is shot forward towards unsuspecting prey.
Another incredible feature of this hunting method is that these birds automatically take into account the refraction that takes place when looking into the water. The head of a heron corrects for light refraction at the water’s surface by adjusting the position and keeping a constant relationship between real and apparent prey depth.
Where do they occur in South Africa?
In South Africa, there are very few reliable places to find this endearing species with several sites along the garden route and Eastern Cape, Lake Phobane in Kwa-Zulu Natal and Lake Albasini in Limpopo offering some of the better chances.
