Zambia–Zimbabwe 2022 hippopotamus (Hippopotamus amphibius) and other species population distribution along Zambezi River

ABSTRACT

A hippopotamus and other wildlife species survey were conducted in the Zambezi River between Kariba dam wall and Luangwa River confluence. The main objective of the survey was to establish hippopotamus and other wildlife species population distribution and densities along the Zambezi River. The boat survey method was used on both sides of the river in October 2022 for 262 km. Individual hippopotamus counted were 1769 on the Zambian side and 1424 on the Zimbabwean side. The Zimbabwean side recorded higher hippopotamus pods (138) than the Zambian side (123). Individual hippopotamus density was 26.60/km with a pod density of 0,45/km. There was a significant difference in hippo population between the five Zambezi River sections on the Zambian side ($x^2$ = 2345, df = 4, p = 0.01) and Zimbabwean side ($x^2$ = 538, df = 4, p = 0.01). The study established areas with high hippo and other wildlife species population distribution and densities, and the study helps to inform management of protected areas’ carrying capacities and management of Human Wildlife Conflicts. The study recommends more studies on hippopotamus migration, population demography, variation in home ranges and regular population surveys in both rivers and inland waterholes.

KEYWORDS:

• Boat survey
• hippopotamus
• population
• Zambezi river
• Zambia
• Zimbabwe

Acknowledgments

We are grateful to the African Wildlife Foundation (AWF) for the funding given to Zimbabwe Parks and Wildlife Management Authority’s (ZPWMA) Scientific Services, Terrestrial Ecology Unit (Zimbabwe) and the Department of National Parks and Wildlife’s (DNPW) Research Department (Zambia). We thank the Zimbabwe Parks and Wildlife Management Authority and the Department of National Parks and Wildlife Director Generals for the permission to work in protected areas of Zimbabwe and Zambia, respectively. We greatly recognise the support of Regional Manager F. Chimeramombe and Senior Area Manager E. Ngosi. On the Zimbabwean side, we are grateful to Blake Muil of Rukuru Camp for the provision of a boat and coxswain. We thank Charleton McCallum for the fuel provision for the survey. We are grateful to ZPWMA Senior Ranger M. Siachombe, Senior Ranger N. Mkunkuli and Ranger I I. Muchena for the data collection and escort. We thank Zambian data collection officers Senior Ranger S Sulumesi, Senior Wildlife Police Officer B Wishikoti and Wildlife Police Officer B Mutanga for the pivotal role they played in data collection. On the Zambian side, we thank Conservation Lower Zambezi, Kulefu camp, Chongwe confluence and Chirundu DJOC for the facilitation of a joint hippo survey. We are grateful to the late Senior Warden H Kayeyi and J Morgan for the facilitation of the research permit for Zambia. We also thank several tour operators from the Zambian side who provided refreshments to the research team.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The study received financial support from the African Wildlife Foundation.