Southern Ground Hornbill
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Southern Ground Hornbill
The southern ground hornbill (Bucorvus leadbeateri; formerly known as Bucorvus cafer), is one of two species of ground hornbill and is the largest species of hornbill. The other species of the genus Bucorvus is the Abyssinian ground hornbill, B. abyssinicus.
This is a large bird, at 90 to 129 centimetres (35.4 to 50.8 in) long. Females weigh 2.2 to 4.6 kilograms (4.9 to 10.1 lb), while the larger males weigh 3.5 to 6.2 kilograms (7.7 to 13.7 lb). Among standard measurements, the wing chord has been measured from 49.5 to 61.8 cm (19.5 to 24.3 in), the tail from 29 to 36 cm (11 to 14 in), the tarsus from 13 to 15.5 cm (5.1 to 6.1 in) and the culmen from 16.8 to 22.1 cm (6.6 to 8.7 in). Per Stevenson and Fanshawe, the Abyssinian ground hornbill is the larger species on average, at 110 cm (43 in), than the southern species, at 102 cm (40 in), but published weights and standard measurements contrarily indicate the southern species is indeed slightly larger.
The southern ground hornbill is characterized by black coloration and vivid red patches of bare skin on the face and throat (yellow in juvenile birds), which are generally believed to keep dust out of the birds eyes while they forage during the dry season. The white tips of the wings (primary feathers) seen in flight are another diagnostic characteristic. The beak is black and straight and presents a casque, more developed in males. Female southern ground hornbills are smaller and have violet-blue skin on their throats. Juveniles to six years old lack the prominent red pouch, but have a duller patch of grey in its place.
Breeding and life cycle
The southern ground hornbill is an obligate cooperative breeder, with each breeding pair always assisted by at least two other birds. It is known via experiments in captivity that birds without six years experience as helpers at the nest are unable to breed successfully if they do become breeders. This suggests that unaided pairs cannot rear young and that helping skill as a juvenile is essential for rearing young as an adult.
In captivity, a maximum lifespan of 70 years is recorded, and it is generally believed that the life expectancy of a bird that survives long enough to fledge is as high as thirty years or more, which is comparable to more famously long-lived birds like the wandering albatross.
Ground hornbills are believed to reach maturity at six to seven years, but very few breed at this age. Nests are almost always deep hollows in very old trees, though there exist reports ground hornbills have on occasions nested on rock faces. One to three eggs are laid at the beginning of the wet season but siblicide ensures that only one nestling is ever fledged. The eggs measure 73 millimetres (2.87 in) by 56 millimetres (2.20 in) and are pure white in colour but very rough in texture.
The period of parental dependence following a 40 to 45-day incubation period and an 85-day fledging period is between one and two years depending on climatic conditions before young are independent of parents and helpers, which is the longest of any bird. This means that ground hornbills can normally breed successfully only every third year. Triennial breeding is extremely rare in birds: probably the only other bird which breeds on a triennial basis is the ornate hawk-eagle of Neotropical rainforests.
Owing to large scale clearing of the bird’s specialised habitat for agriculture, along with its exceedingly slow reproductive rate, the southern ground hornbill is classed as vulnerable to extinction; however, in South Africa, where most studies on the species have been carried out, it is listed as critically endangered.
CeltickRanger ha puntuado esta nota como útil.
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super good sharpness and good details of this bird
nice light with beautiful colours
thanks gr lou
- [2015-12-22 8:23]
What a great surprise to see your new posting! And a fantastic one.
Superb sharpness, splendid natural colours and taken from a very good low POV.
Merry Christmas to you and your family.
- [2015-12-22 11:32]
Hi Carl,a magnificent capture of this rare hornbill,very hungry as i can see..ehehe..very nice walking pose and impressive sharpness and colors,useful note too.I wish you a Merry Christmas and thanks for share,Luciano
Ciao Carl, great capture of fantastic bird, wonderful colors, fine details and splendid sharpness, very well done, my friend, Merry Christmas and Happy New Year 2016, ciao Silvio
- [2015-12-22 18:50]
How neat to see a post from you once again, and what an impressive one at that. It has such an intimidating facial expression, just look at those piercing eyes. I'm sure it lets others know it is the boss. Tac sharp focus displaying excellent detail and rich natural colors. Considering it's thick muscular legs, stout bill and stern looking face, I would hate to run into one of these guys in a dark alley:). Well done!!
- [2015-12-23 10:50]
Nice colours and sharpness details,perfect capture of very interesting bird.
WOW ! great close-up shot of this expressive bird,
very fine POV at its level, photo shot at the best moment
of the pose while the Ground Hornbill is walking,
great details of its dark plumage, TFS
Hey Carl ... wonderful work my friend !!! Merry Christmas !
MERRY CHRISTMAS AND WISH YOU HAVE A NICE AND HEALTHY NEW YEAR.
SORRY Carl, no green similes but best regards to you.
Beautiful image of this endangered ground hornbill. Sharp, great feather detail and nice composition.