NZG | e-News: The hornbill - the rhinoceros bird
Despite their diminutive stature, dwarf mongoose are a fascinating species mongooses in the presence of insect-eating birds like hornbills, Where this relationship is formed you will often see the same individual hornbill. There is a positive relationship between the number of mongooses in the group and the number of birds accompanying them. A true mutualism only exists. The prey spectra of the mongooses and hornbills overlap For the other bird species forming the foraging community only partial overlap exists. There is a positive relationship between the number of mongooses in the group and the.
It is not absolutely clear why this might be but it is suspected that it is due to movement of the sun.Drongo Bird Tricks Meerkats - Africa - BBC Earth
Of course here in the Southern hemisphere the north side of the termite mound will receive the most sun throughout the day. It is thought the heat emphasises the effectiveness of the scent marking meaning that the scent from the north side permeates the whole mound.
They will also mark territorial boundaries and have permanent latrines close to their sleeping dens that serve as scent marks and are used for several weeks at a time. It is the immigrants that stand the best chance of assuming a dominant position at a later stage.
The successor of a dominant female is decided not by fighting but by an intense grooming competition. The mongoose with the greatest endurance will be the new dominant female. Typically the males will fight to determine dominance with groups of males teaming up to oust dominant males of another group in order to replace them. Dwarf mongooses have an advanced vocabulary which is put to good use by their sentry system. They have a host of natural enemies including slender mongooses, snakes, black-backed jackals, and birds of prey.
As a result, whenever the business is outside of the den a sentry will be on duty looking out for predators. They have cheeps that signal that it is safe to leave the den and have different alarms to indicate a predator on the ground and one in the sky.
The hornbill and the dwarf mongoose
As an additional precaution dwarf mongooses never stray further from a bolt hole than the alarm of a sentry will carry. Whilst dwarf mongooses are out of a den you will often hear them chattering to one another. The birds catch insects that have been disturbed by the foraging of the mongooses and the mongooses benefit as the birds act as an additional sentry system.
In particular, hornbills have been observed sounding alarms in the presence of dwarf mongooses for predators that hold no danger for the bird but only for the mongoose. Where this relationship is formed you will often see the same individual hornbill continually associating with the business of mongooses. Each morning the hornbill will show up at the den where the dwarf mongooses have spent the night, if the group are not yet awake the bird will call down to wake them up and wait whilst they all emerge before they head off to forage together.
Interestingly if the hornbill fails to show up one morning the mongooses have been noted to be agitated and restless, delaying their departure as long as they can and even sending individuals back to the den to check for the missing bird.
The whole business will mob a snake until it is exhausted and then the dominant female will kill it with a bite behind the head.
Intriguing facts about the dwarf mongoose - Africa Geographic
Snakes are the only prey that is shared amongst the group. We are lucky to observe these busy mammals around Bushwise campus on a regularly basis. Their constant banter with each other is fascinating and they are not still for very long.
In the Helmeted hornbill Rhinoplax vigilthe tip of the casque is filled with solid ivory and is used as a battering ram in dramatic aerial jousts. Both the scientific and English name of the family refer to the shape of their bill; "buceros" being "cow horn" in Greek.
Hornbills are the only bird species that possess a two-lobed kidney, as all other birds have a three-lobed kidney.
They are also the only bird in which the first two neck vertebrae the atlas and axis are fused together, providing them with more stability to carry their heavy bill. Their powerful neck muscles assist in holding up their heavy bill, which is used in fighting, preening, constructing nests and catching their prey.
There are two subfamilies - the Bucorninae consists of the two Ground hornbill species in a single genus and the Bucerotinar contains the remaining number of species.
Hornbills come in a range of sizes from the Dwarf red-billed hornbill Tockus camurus of grams and 30 cm in height to the Southern ground hornbill Bucorvus leadbeaterisome specimens of which stand at 1.
Dominantly, males are bigger than the females across the different species and sexual dimorphism occurs according to various body parts, such as the length of the bill, wingspan, colours on their face and throat and their body mass. The typical plumage of hornbills is black, grey, white or brown and typically offset with brightly coloured bills. Some hornbills have bare coloured skin on the face or wattle too. The calls of hornbills are loud and vary distinctively between species.
They have binocular vision and unlike most birds with this type of vision, the bill intrudes on their visual field, allowing them to see their own bill tip, which assists them in their precision of handling food and other objects. Their eyes are protected by means of large eyelashes that act as a sunshade.
Sabi Sabi Wild Facts: Dwarf Mongoose
Hornbills are diurnal and generally travel in pairs or small family groups. During the non-breeding season, larger flocks may form and assemble at roosting sites in large numbers. Distribution and habitat Hornbills are found in tropical and sub-tropical Africa and Asia, inhabiting a wide range of habitats from the Namib Desert to the tropical rainforests of south-east Asia. Most hornbills are arboreal birds living in treeswith the two larger Ground hornbills being terrestrial birds of the open savanna.
Thirteen of the 28 species in Africa are found in open woodlands and savanna and even in highly arid regions. The remaining 23 species are found in dense forests.
Diet Hornbills are omnivorous with a range of diets - from several species solely being carnivorous to others wholly being frugivorous fruit eating. Their carnivorous diets consist of insects, lizards, frogs, small mammals as well as other birds. Fascinatingly, all the savannah and prairieland species are carnivorous, whilst all the frugivorous species are forest dwellers.
However, a number of Tockus species are forest dwellers yet primarily carnivorous insectivorous too. Hornbills that are forest dwellers are considered important seed dispersers. Hornbills cannot swallow food that has been caught at the tip of their beaks as they have a short tongue which cannot reach, thus they toss their food back into their throat with a jerk of the head.
Wild Facts Sabi Sabi Private Game Reserve | Dwarf Mongoose
Most hornbills gain all the moisture that they need from their food, and thus hardly ever drink water, with their food intake varying throughout the year depending on what is available. Breeding Sexual maturity of the smaller species is reached in one year, medium species in two years and the larger species in three to six years. Hornbills are commonly monogamous breeders, with some species engaging in cooperative breeding.
They nest in natural cavities in trees, cliffs and even abandoned nests of woodpeckers and barbets that may be used in consecutive breeding seasons by the same pair. Up to six white eggs are laid. Before incubation the female of the Bucerotinae species begins to close the entrance to the nest cavity with a wall of mud, fruit pulp and droppings, occasionally assisted by the male.
Once the female is ready to lay her eggs, the entrance is still big enough for her to enter the nest, but as soon as the eggs are laid, she seals the remaining opening shut and remains inside with her eggs. However, a small gap is left open for the male to transfer food to the female and to the chicks at a later stage. This behaviour is apparently to protect the nesting site from predators and rival hornbills. During the incubation phase, the female moults her flight feathers completely and simultaneously for the nest and to keep her chicks warm.
An average clutch size for the larger hornbill species is one or two eggs, but in the smaller species they lay up to eight eggs.
When the mother and her chicks are too big to fit in the nest, the mother will break out and both parents will then feed the chicks.