Hirola have been described as graceful, majestic and elegant but they can be vicious especially when protecting their territories. The adult male hirola have been observed to secure, hold and vigorously defend their territories.
Hirola exist in social groups that can range from 5-40 individuals. Each of these groups are usually accompanied by an adult male considered to be the ultimate leader. While such groups are fairly stable, hirola bachelor herds are quite the opposite. Their associations are mostly temporary with mixed or single sex herds.
True to type, and not long ago, a subordinate male broke away from his bachelor herd and was seen trailing another herd of seven individuals. Despite all attempts by the dominant male to mark his territory and claim supremacy, the subordinate male cautiously followed them. The dominant male on the other hand, marked his territory using secretions and dung, scrapped the soil using its hooves and slashed vegetation with his sharp lyrate horns. All these were clear warnings to remind the intruder that he will fight to defend his territory. Studies elsewhere and on other species indicate that the dominant male fights the bachelors to drive away competition especially for females during mating (Bro-Jorgensen 2002).
Despite the intimidating threats from the dominant male, the subordinate male made his intentions clear that he was there to take over. He was chased away several times by the dominant male, but relentlessly and stubbornly, continued to return and consistently kept close at a distance of about 100m from the group. It seemed like he was waiting for the right moment to strike and claim dominance of the group.
On one moonlit night of early January 2018, the lone male challenged the dominant male to a duel. To both of them, this was a fight to either dominance or death. Antelopes use their horns to fight and occasionally would use their rear legs to push forward after standing on their hind legs. The male hirola horns are beautiful but heavily ringed than females and are extremely sharp to cause maximum damage to their opponents during a fight. Packer (1983) observed that antelopes use their horns both in head to head combat with competitors and also in stabbing of predators. Hirola’s skin is also quite thick at the nape and fold up behind the horns to offer a degree of protection against the sharp horns of an opponent.
When the lone male decided to charge at the dominant male, the later knelt and pointed his horns towards the challenger. In a matter of seconds, the ungulates locked horns in a fascinating show of might and power. Again, and again their horns locked, each time with increased momentum and rage like the battle of the titans. The two engaged each other close to half an hour before they showed signs of slowing down. Their energy and fighting intensity suddenly appeared to come down, and both looked exhausted. This however was short-lived, and on one last show of might, the dominant male reared up on his hind legs and within a split of a second came roving down on the lone male so hard that the impact sounded like the explosion of a thunderstorm. Everything went quiet for a moment as both of them lay still. Their horns had interlocked and on a closer look one of them had ended up with a broken neck.
The dominant male had emerged the stronger, but in war, there are seldom any sacred souls. As the intruder male lay dead, the dominant male appeared exhausted, weak and wounded. In vain he attempted to get up. After a few failed attempts, the victor gave in to fate and was lying dead few minutes later.
Many examples of dominant males fighting off their opponents have also been reported for other species including Oryx, waterbuck etc. (Paton 2001; Caron 2005; Spinage 2012). In 2012, 48 hirola individuals were translocated from the periphery of the Boni forest in to a 25 KM2 sanctuary. The population has since doubled with nearly 50% of all the new borns thought to be males. In 2014, similar male battles have been reported by our scouts inside the hirola predator proof sanctuary. While most of these fights are more common in sanctuaries with limited space, it is possible to limit aggression between antelope opponents even in such settings. For example, antagonistic behaviors of bachelor herds within a sanctuary can be minimized through reducing aggressive hormones such as androgens and increasing melengestrol acetate given with feed or administered directly (Patton 2001; Penfold et al. 2002). This was found to significantly reduce the aggressive behavior in such herds. Further, the size of an enclosure has an impact on the level of aggressiveness. Studies have indicated that dominant males in small enclosures were more aggressive due to restricted environments (Cassinello and Pieters 2000). This means that the establishment of larger sanctuaries can reduce the level of aggressiveness and limit the risk of fatalities. It is also good practice to avoid having surplus bachelor males in a herd as this will increase competition for mating and lead to aggression and endless fights for dominance.
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