Lion predation on the African Black Rhinoceros

[Sully]

http://africageographic.com/blog/rhino-p...er-threat/                                                         (click on the article for the pics)

Rhino populations face another threat
Posted on 15 May, 2015 by Roan Plotz  in Animal Encounters, Conservation — No Comments
Posted: May 15, 2015
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Rhino are big animals, have rapier like horns and near impenetrable hides – unluckily this offers little defence against modern man and the rifle. But adult rhino are seemingly able to fend off large non-human predators, like lion and spotted hyenas, without too much fuss.

*This image is copyright of its original author

© Dale R. Morris

However, increasing reports of lions and hyenas attacking juvenile black rhino suggest that its prevalence might be higher than previously appreciated. It might seem that with the current poaching crisis that non-human predation is a mere drop in the ocean – nothing to worry about in the scheme of things. Nevertheless, its prevalence in some key rhino reserves responsible for overall species recovery might be higher than expected.
It was with this in mind that I decided to look for evidence of black rhino calf predation by lions and hyenas. In Hluhluwe-iMfolozi Park, South Africa, managers started to raise ideas about what might be causing the low calf recruitment rates they were recording. Direct evidence was lacking but a spike in hyena and lion densities in Hluhluwe-iMfolozi caused concern. Elsewhere in Africa, others reported incidences of marauding hyenas distracting black rhino mothers while dragging off their young. In Tanzania’s Ngorongoro Crater, four out of seven calves that died in a 12-year period succumbed to predation by lions.
In my previous blog post (Earless black rhino –are they stone deaf?) I wrote about ‘Earlessness’ in black rhino and the fact that it might be linked to failed predation attempts. Earlessness and tail loss in black rhino can be as much as 7% in some populations. Although suspected to be due to failed depredation attempts, actual observations of predators removing ears or tails were lacking.

*This image is copyright of its original author

Photo of a black rhino missing a tail in 1983 in Hluhluwe-iMfolozi Game Reserve © Pete Hitchins

I was fortunate enough to be able to put radio-transmitters into the horns of 14 black rhino in Hluhluwe-iMfolozi that allowed me to track them on-foot on a daily basis.

*This image is copyright of its original author

© Roan Plotz

On the 14 August 2008, I was in the Nqumeni section of Hluhluwe-iMfolozi when I sighted an adult female accompanied by her female calf with injuries. The calf ’s injuries included tissue trauma to the anogenital region with an amputated tail, claw or canine puncture wounds to the neck region, and skin lesions resembling claw marks to the rump and right posterior flank.

*This image is copyright of its original author

© Roan Plotz

*This image is copyright of its original author

© Roan Plotz

On four subsequent occasions the adult female was sighted without her calf. Eight-month-old black rhino calves are still nutritionally dependent on their mothers and so the confirmed disappearance of the calf suggests that the calf succumbed to its injuries.

*This image is copyright of its original author

© Roan Plotz

Three characteristics about the sighting are consistent with an attack by at least two lions. Puncture and tear wounds at the calf ’s neck suggest one lion attempted to suffocate the calf in the fashion typical of lion attacks on ungulates. Tissue trauma, severed tail, and claw marks suggest that another lion attempted to feed from the anogenital region. The skin lesions at the rump and along the back and flank of the calf were characteristic in spread and size of lion claws and canines.
Predation on black rhino juveniles might be under-reported because both births and carcasses are rarely detected. Neonatal black rhino calves are cryptic and difficult to sight. Not only are they small but mothers tend to be sedentary in densely vegetated habitat during the calves’ first months of life. Moreover, on the few occasions that field rangers recover black rhino calf carcasses the cause of death is rarely determinable.

*This image is copyright of its original author

© Dale R. Morris

Conservation managers rarely factor in predation when managing a black rhino population for improved productivity, although predation’s role in Hluhluwe-iMfolozi’s black rhino population performance has been debated before. Poor population performance has largely been attributed to density dependence but evidence suggests that predation of black rhino juveniles may also, at least in part, account for longer inter-calving intervals, low numbers of calves per adult female, and poor population growth. It might not be realistic to expect a black rhino population living with high densities of lions and spotted hyenas to grow as fast as one in a reserve without large predators. When attributing cause to poor population performance the presence of large predators should at least be considered.

*This image is copyright of its original author

Two short-sighted rhino seemingly oblivious to a lioness overhead in a Marula tree in Hluhluwe-iMfolozi Park © Roan Plotz

Hluhluwe-iMfolozi, like any reserve across Africa, is facing ongoing waves of poachers attacking its rhinos. With the current intensity of the poaching crisis, it is easy to think that once the poachers are stopped the rhino populations will continue to flourish. The solution to ongoing species recovery will require other factors to be monitored – like predation.

*This image is copyright of its original author

Rhino spoor next to lion tracks in a riverbed © Roan Plotz Reply