hunting and wildlife trade in tropical forests (lecture 10) Flashcards
Why are even non-deforested tropical forests in trouble?
- hunting and destruction of wildlife
- even in nature reserves
- truly undisturbed forests are pristine, overhunted are half-empty
What is the extent and scale of the harvesting of tropical wildlife?
- 50% amazon forest within 3km of nearest river/road
- animal population sizes increase with distance from access points
Peres, 2000
- rural population density (1996) = 1.61 individuals per km2
- 15.79 million game mammals consumed a year, 148,150 tons
- bushmeat death toll highest in africa (17 large arnimals per km2 annually), latin america (7), southeast asia (6)
- congo basin
- 13.1 ind./km2 rural population
- ~1.2 million tonnes of bushmeat
- 645kg/km2/yr
How much wild meat can a kilometre squared of tropical forest sustainably provide annually?
- 1 km2 can provide for a single person
- rural population in congo 13.1 individuals per km2
- current hunting rates v unsustainable
- hunting = major threat to large bodied tropical forest vertebrates
Why does hunting occur?
- subsistence and local trade
Subsistence and local trade
- only option for poor
- only source of animal protein
- available to anyone willing to hunt
- cheaper than domestic substitutes
Why does hunting occur?
- cultural/traditional reasons
Cultural/traditional reasons
- feathers, leather, bones etc: traditional garments, accessories and weapons
- festivals/ceremonies: religious, celestial
- religious merit release: legal trade in wild caught birds, including IUCN red list species
- worth $235,000
- 680,000 birds per year
- 2 temples in Phnom Penh
Why does hunting occur?
- mecidinal
Medicinal
- huge market for natural medicines in S.E Asia but globalisation is increasing
- tiger bone, claws, fat, eyes, brain, penis, etc
- brain cures laziness
- bile treats convulsion in children with meningitis
- $70,000 in China
- rhino horn: status symbol/hangover cure - $97,000/kg
Why does hunting occur?
- luxury meat
- local delicacies
- huge market in SE Asia
e. g. Pangolin
- for meat
- scales for medicine
- over 13 months (2007/08) in Sabah, Malaysa
- middle men spent $3.5M on 108 tonnes whole pangolin ($32/kg) and a tonne of scales ($51/kg)
- market price in Cambodia is $300/kg meat, $3000/kg scales
How does rarity affect wildlife trade?
- relative trophy price increases with rarity, controlling for body size and location
Why does hunting occur?
- cagebird & pet trade
cagebird trade:
- esp east/south-east asia
- 3,337 species
- also reptiles/frogs, invertebrates like tarantulas and mammals, including primates
- anything that is cute when young
- mother usually killed
- international market
What are the direct consequences of hunting in tropical forests?
Peres (2000)
- lots of groups variable in what species decline/increase from non-hunted to hunted sites
e. g. some primates increased, some decreased - rodents increased
- competitive release
- species with higher body mass decreased from non-hunted to hunted sites
How have forest elephants in central africa?
2002-2011
- 62% reduction in population size
- 30% geographic range
- populations <10% potential size
- occupies <25% potential range
- avoidance of hunters
How damaging is the ivory trade?
- ivory highly valued in china, philippines, thailand etc
- china has agreed to phase out ivory industry to combat elephant poaching
What happened to the Javan rhinoceri?
- last one shot in Cat Tien National Park, VN
- scat sniffer dogs last detected dung in early feb 2010
- remains found in late april 2010
- DNA from all dung piles match with remains
- rhino horn worth more than its wait in gold
Why is preventing extinction of large game animals hard?
- illegal wildlife trade is extremely lucrative
- perpetrators well-organised and well-armed
- criminal gangs e.g. Lord’s Resistance Army, Janjaweed
- helicopters to gun down African elephants herds
- financially worthwhile to seek last individuals of dwindling populations
- anthropogenic Allee effect
- premium on rarity drives extinction
What are the direct consequences of hunting in tropical forests?
- hunting/wildlife trades driving declines in many species
- big shifts in biomass/size structure of vertebrate assemblages
- local (near-)extinctions of large vertebrates
- can drive global extinction of particularly valuable species
- premium on rarity
