William Crosmary

Last update: 21 January 2018

Title: The effects of sport hunting and its different organisation methods at the periphery of protected areas on fhe African ungulates populations structure and their spatial distribution.

Summary

Like predation, trophy hunting may constrain ungulates to adjust their behaviour to decrease mortality risk. Moreover, because this removal is size selective and male-biased, it may induce morphological changes towards individuals with smaller traits, alter population structure and dynamics. Trophy hunting is one of the conservation modes of natural habitats, particularly in Africa. However, its conservation potential is still fuzzy because there are few studies outside National Parks. This thesis aimed to investigate the subtle effects of trophy hunting on African ungulates, i.e. on their behaviour, horn length of harvested males, proportion of adult males, group size, and population densities. I worked from behavioural observations, and from population data of long-term surveys. For several species (mainly impala Aepyceros melampus, greater kudu Tragelaphus strepsiceros, and sable antelope Hippotragus niger), I compared behaviour, population structure, and densities between Hwange National Park and adjacent hunting areas, Zimbabwe. In hunting areas, I analysed trends in horn length of harvested males over the past 30 years. This thesis shows that ungulates drank more often at night, and were more vigilant in hunting areas than in the national park. However, the amplitude of these adjustments was constrained by the need of surface water, and by natural predation risk. Trophy hunting caused a decline in horn length, particularly for species that experienced high hunting pressure and were of high value for hunters. Trophy hunting tended to decrease proportion of adult males, though not significantly, and did not affect group size. Moreover, during the last 30 years, ungulate densities generally declined more in the national park than in neighbouring hunting areas. This suggests that trophy hunting played a minor role on densities compared to other factors, i.e. rainfall, and possibly natural predation and elephant densities. Despite behavioural adjustments induced by hunting risk, decline of horn length, and harvest skewed towards adult males, ungulate densities in hunting areas adjacent to Hwange National Park remained comparable to densities within the national park. This study illustrates how trophy hunting areas, when rigorously managed, may play a significant role in the conservation of ungulates in Africa.

Last update: 21 January 2018