ACTIVITY BUDGET AND FORAGING PATTERNS OF NUBIAN GIRAFFES (Giraffa
camelopardalis camelopardalis) IN LAKE NAKURU NATIONAL PARK, KENYA
Abstract
The behavior of animals potentially affects their survival and
reproduction. The activity budget of the Critically Endangered giraffe
Giraffa camelopardalis camelopardalis has been investigated in
populations across Africa and found to be influenced by body size, diet
and sex. Foraging patterns show how an animal chooses to forage in its
environment, and is influenced by resource availability, competition and
predation risk. The activity budget and foraging patterns of Nubian
giraffes vary considerably between ecosystems. The Nubian giraffe is a
recently identified subspecies G. camelopardalis camelopardalis). This
Critically Endangered giraffes which includes Rothschild’s giraffes,
occurs only within Kenya, Uganda, Ethiopia, and Southern Sudan. We
observed the behavior of a population of Nubian giraffes in Lake Nakuru
National Park, Kenya, to assess seasonal activity budgets and foraging
patterns. In the wet and dry seasons, giraffes spent approximately the
same amount of time (53 and 57%, respectively) foraging. Movement and
resting duration decreased slightly from the dry to the wet season (22
to 20% and 25 to 22%, respectively. Across both seasons, Vachellia
xanthophloea (67%), Maytenus senegalensis (19%), and Solanum incanum
(9%) made up the bulk of the giraffe’s diet. In the dry season, giraffe
additionally foraged on Maerua triphylla (2%), Vachellia gerrardi
(2%), and Grewia similis (1%); in the wet season, they added Vachellia
abyssinica (2%) and Rhus natalensis (2%) to their diet. The most
utilized browsing height was 3.5 m below their average height.. Overall,
season did not appear to influence the Nubian giraffe’s activity time
budget or foraging patterns in Lake Nakuru National Park. Improved
knowledge of the behavioral patterns of this subspecies will allow
managers to manage and conserve the species and its habitat better. For
instance, planting perennial plants in all vegetation types used by
giraffes in the park minimizes browsing pressure on the already over
browsed Vachellia.