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WALLACE RESOURCE LIBRARY Lecture 08 – Predators of South Africa. This is an ‘example’ of a lecture that is given to A level students as part of their academic lecture series whilst on their expedition.
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WALLACE RESOURCE LIBRARY Lecture 08 – Predators of South Africa This is an ‘example’ of a lecture that is given to A level students as part of their academic lecture series whilst on their expedition. It has been produced for the exclusive use of the lecturer conducting the series and is solely intended for educational purposes. Most of the material comes from Operation Wallacea sources and any other material that has been used has been credited (as far as is possible) to the appropriate author wherever possible. This lecture is only to be used for EDUCATIONAL purposes.
WALLACE RESOURCE LIBRARY Lecture 08 – Predators of South Africa
Lecture overview • Introduction to key species • Lion • Leopard • Cheetah • Hyena • African Wild dog • Population monitoring • Comparing hunting strategies
Lion Distribution and Conservation Status • Lions (Panthera leo) range in parts of sub-Saharan Africa • IUCN status as vulnerable but 30% reduction in population over last 2 decades • Primary threat to lion population is human activity
Lion Social and Hunting Behaviour 2 types of social organization: residents and nomads Male cubs expelled from pride upon reaching sexual maturity Male coalitions aggressively take over prides, expelling existing males and killing infants Infanticide sexually selected behaviour Co-ordinated hunting, primarily by females, but males assist with hunting larger prey such as buffalo
Leopard Distribution and Conservation Status • Leopards range across Africa and Asia • African leopards (Panthera pardus) are the nominate form, but there are 9 other subspecies • IUCN status near threatened • Disappeared from 37% of original range
Leopard Social and Hunting Behaviour Large skull and jaw muscles enable leopards to capture large prey Diet includes over 90 species Prey is killed and then dragged up a tree away from other predators Solitary animals that are aggressive towards each other outside of mating
Cheetah Distribution and Conservation Status • Cheetah (Acinonyx jubatus) range widely, but sparsley throughout Africa • Southern Africa is their regional stronghold • Used to range throughout Asia, but now only one subspecies remains (A. j. venaticus), that is critically endangered and found only in Iran • Disappeared from 76% of original range • IUCN status vulnerable
Radiation & decline - Cheetah • Cheetah sole survivor of specialised & distant branch of the cats • Through a huge population crash, their genes are lacking diversity • Whole Genus, Cheetah included, in final stages of long & inevitable natural extinction
Cheetah Social and Hunting Behaviour Prey (small to mid sezed ungulates) caught in high speed chases up to 103kmh-1 Hunt during the day when competition from other predators is low Solitary females with dependent offspring Males either solitary or in stable coalitions with other males Coalition males may or may not be related
Hyena Distribution and Conservation Status • Brown hyena (Hyaenabrunnea)rangesthroughoutsouthernAfrica • IUCN nearthreatened • Spotted hyena (Crocuta crocuta) ranges throughout all sub-Saharan Africa • IUCN least concern
Hyena Social and Hunting Behaviour Scavengers that can digest all organic components of bone Live in clans Female dominance and females remain in their natal clan Males assist with raising cubs Fission-fusion social system
Wild Dog Distribution and Conservation Status • African wild dog (Lycaon pictus) range throughout sub-Saharan Africa • However, virtually eradicated from Western, Central and North-Eastern Africa • IUCN status endangered • Principal threats to population are human activity and infectious disease
Wild Dog Social and Hunting Behaviour Hunt in packs and primary prey are medium-sized antelope Separate male and female hierarchies within the pack Oldest female in pack most dominant Dominant male either the youngest adult male or the father of the other males
Population Monitoring • In small reserves, carnivore population can be counted exactly and records kept of all births and deaths • In large reserves it is often necessary to calculate population density estimates using sampling techniques
Population Monitoring • Distance sampling • Walk at a steady pace along a transect line and record all mammals encountered, noting the species, number of individuals and perpendicular distance from the transect line • Suitable for animals that will tolerate human presence such as arboreal primates Diagram by Sutherland, 2006
Population Monitoring • Radio Telemetry • Used to collect baseline data such as home range size, daily movements, use of home range • Used when dealing with animals that are difficult to observe because they are secretive, live in habitats with thick vegetation or because they are most active at night • Animal is anaethetized, fitted with a radio collar and then released
Population Monitoring Radio Telemetry Receiver is tuned to the same frequency as the radio collar Directional aerial allows researcher to pinpoint approximate location of the collared animal Exact location pinpointed using triangulation Modern VHF radio collars can turn themselves off at set times to save battery life and send a different signal when the animal is active rather than resting
Population Monitoring GPS Collars Use the Global Positioning System to record animals exact location and store readings an pre-set intervals Data can be downloaded remotely by radio link or in areas with GSM phone coverage Can also include a VHF transmitter for tracking when animals move out of GSM coverage
Hunting strategies Hunting strategies in hyena, hunting dogs, lions, cheetahs and leopards. • Divide up into small groups and read through the articles you have been given. If you have a big group, each person could do a different animal. • Construct a comparison table (e.g. size, habitat, prey, social behaviour, hunting strategy etc) describing how they are adapted to be predators. • One of you could be responsible for thinking of some comparison headings. • When you have finished, compare these predators in a groupdiscussion. • How and why are the hunting strategies different? • Which do you think is the most successful?