Friedrich von Hörsten wrote:
Why use contraceptives on lions that are a BIG tourist attraction at Addo, and allow the hyenas to keep on breeding freely?
Surely more lions would mean less hyenas as they are know to kill young and older hyenas whenever they can.
The opposite is also true: hyenas surely will kill small unattended lion cubs whenever they can, so maybe there won't even be the need for contraceptives with so many hyenas around at present?
How many spotted hyeans are in Addo at present?
Do the hyenas not have a serious impact on prey animals too? Pics of hyenas surrounding an eland and killing it were shown on this forum recently. I would rather put them on contraceptives and allow the lions to breed once in a while...
To reply to Friedrich's questions above (and I haven't quoted the whole post here), contraception is one of the management tools we use, in conjuncton with translocation, to ensure their is a balance in the ecosystems within the Park. We also need to think about the health of each population's genetics which means we do use contraception and translocation for genetic aims too.
We do need to limit the numbers of lions in the main game area (I'm including the Colchester section in this) since lions have an impact on prey species. Spotted hyena also have an impact on prey species and so we monitor their numbers too. So far, we have translocated some hyenas in the past out of the park to control numbers. We have not needed to contracept them yet as their social structure, as well as the effect of the lions on them, has kept their numbers in the acceptable range. Hyenas have a matriarchal society and if the matriarch is deposed/moved, there is fighting within the ranks to establish a new structure, which can also act to control numbers.
There are 17 spotted hyenas in the main game area presently.
Lions will kill or attack hyenas just as hyenas will kill / attack lions because they are competing species in the ecosystem. It all depends on the relative numbers of each predator at a confrontation as to which species will be the most dominant. It is said that 1 adult lion is equal to 3 adult hyenas in terms of dominance.
We will need to continue to manage the two species with contraception and with translocation in the future.