The diet of caracal (Caracal caracal) in the southern Free State
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Date
2015-12
Authors
Pohl, Carl Frederick
Journal Title
Journal ISSN
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Publisher
University of the Free State
Abstract
Caracal is a damage-causing predator in rangeland ecosystems of southern
Africa, with the southern Free State being one of the most severely impacted small stock
areas. Available literature indicate that these cats usually prey on the most abundant prey
groups, but are also opportunistic and take small stock, especially during lambing seasons.
The aim of this study was to define the diet of caracal over a 13 month period through scat
analysis in a small stock area and to discuss its prey-niche overlap and sharing with the
three most common sympatric carnivores-black backed jackal Canis mesomelas, Cape grey
mongoose Galerella pulverulenta and yellow mongoose Cynictis penicillata. The study site
was described as a productive ecosystem and characterised by a diverse number of prey
species. Prey availability was determined on a number of transects (driven and walked) and
through numerous observations of birth peaks/the presence of young.
Results show that caracal fed predominantly on Mammalia prey (94.74 percentage
occurrence, %Occ.; 93.40 percentage volume, %Vol.). Prey items that made the most
notable contributions to caracal diet were Lagomorpha (28.5%Occ.; 28.0%Vol.), rock hyrax
Procavia capensis (17.5%Occ.; 17.3%Vol.), and springhare Pedetes capensis (15.2%Occ.;
15.2%Vol.) and domestic sheep Ovis aries (13.6%Occ.; 13.6%Vol.). Prey items that made
the most notable contributions to black-backed jackal diet were Muridae (34.43%Occ.;
9.83%Vol.), Lagomorpha (19.94%Occ.; 16.98%Vol.), springbok Antidorcas marsupialis
(13.92%Occ.; 12.92%Vol.), sheep Ovis aries (9.09%Occ.; 8.24%Vol.) and mountain
reedbuck Redunca fulvorufula (9.82%Occ.; 9.42%Vol.).
The current study showed that caracal was more of a specialist than black-backed jackal,
with the latter utilizing the widest prey spectrum. Both caracal and black-backed jackal fed
opportunistically in this study, and their diets included a large proportion of natural prey. The
diet of caracal and black-backed jackal included more mammal and less invertebrate prey
than that of Cape grey mongoose and yellow mongoose.
Of the four predators studied, black-backed jackal diet was the most diverse (widest niche
breadth), followed by Cape grey mongoose, caracal, and yellow mongoose diet the least
diverse. The two larger carnivores, caracal and black-backed jackal, utilised their prey items
with higher evenness than the two mongoose species. Highest niche overlap was observed between caracal and black-backed jackal (1.0), and
between Cape grey mongoose and yellow mongoose (0.9). Moderate niche overlap was
observed between caracal and Cape grey mongoose, and between black-backed jackal and
Cape grey mongoose (both 0.6; smallest overlaps were between caracal and yellow
mongoose (0.3), and black-backed jackal and yellow mongoose (<0.1).
Springhare remains in caracal scats correlated with monthly springhare abundance (r=0.8;
p=0.004), which in turn correlated with humidity (r=-0.7; p=0.03). Hare Lepus spp. remains
in caracal scats did not correlate with hare monthly abundance (r=0.6; p=0.09), but followed
the same general trend. The results suggest that caracal fed on the most abundant prey
and opportunistically exploited peaks in prey abundance.
Both caracal and black-backed jackal preyed markedly on sheep during the two lambing
seasons (March to April and September to October). Black-backed jackal predated less on
this prey item than caracal, but predated, more than caracal, on (also economically
important) springbok. Both caracal and black-backed jackal were, therefore, damagecausing
predators in the study area, but also played an intricate role in the ecosystem in that
they regulate prey populations and may benefit syntopic carnivores through, for example,
carrion provision. Caracal and black-backed jackal may also serve as regulators of prey
species that are also potential damage-causing animals (e.g. rodents destroying crops and
carrying disease, hyrax competing for forage with sheep, and molerat tunnels causing
damage to tractors and plows).
Although the current research was a descriptive ecological study of caracal diet in a
rangeland ecosystem, and not a management focused project, it nevertheless provided
information that can benefit farmers, conservation authorities and the government sector in
the quest to address the sensitive issues of predator control and ecosystem conservation on
rangelands characterised by major small stock losses.
Description
Keywords
Caracal caracal, Damage-causing predators, Diet, Major prey, Minor prey, Niche breadth, Niche overlap, Predator-prey interactions, Syntopic carnivores, Small stock, Dissertation (M.Sc. (Zoology and Entomology))--University of the Free State, 2015