Lecture 10 - hunting and wildlife trade in tropical forests

Question 1

what is a ‘silent forest’

Answer 1

half empty forest due to hunting

• small number of species consuming large biomass of animals
• hunting is already higher than wildlife can sustain

Question 2

how is density affected by accessibility

Answer 2

• density increases the harder the accessibility - only 1.6% of the Amazon is protected and inaccessible to hunters

Question 3

why is hunting such a threat to tropical forests

Answer 3

each km2 of tropical forest can only sustainably provide for the annual wild meat protein needs of a single person - currently hunting is exceeding this and is a major threat to large-bodied vertebrates

Question 4

why does hunting occur?

Answer 4

• subsistence and local trade - cheap and available to anyone that can hunt
• cultural/traditional reasons - garments and ceremonies
• religious (merit) release - releasing birds at temples
• medicinal, luxury meats etc - e.g. tiger brain cures laziness
• trophy hunting - as rarity increases so does price
• pet trade - kill mothers

Question 5

what are direct consequences of hunting?

Answer 5

• faunal changes - small animals become more abundant due to less predation
• decline in mean body mass - hunt larger animals
• catastrophic losses of enigmatic fauna
• extinction

Question 6

describe what has happened to forest elephants

Answer 6

massive decline
trophy hunting for tusks/ivory
population declined by 62%
lost 30% of geographical range
population <10% of potential size and occupies <25% of potential range
china has no made carving ivory illegal and cant bring in any illegal ivory

Question 7

describe an extinction from hunting

Answer 7

• last Javan rhino shot in Cat tien national park

- horn worth more than its weight in gold

Question 8

why is illegal wildlife trade so lucrative

Answer 8

• perpetrators are well armed and organised e.g. criminal gangs with helicopters to gun down african elephant herds
• financially worthwhile to seek out last individuals of dwindling populations
• can drive anthropogenic allee effect - premium on rarity drives extinction
• CITES listed = illegal to trade = cost alot more

Question 9

what are indirect consequences

Answer 9

• bigger seeds ingested by bigger primates = redundancy in seed dispersal for large seeds = decrease in forest size
• wind dispersal plants are the only ones doing well in hunted sites
• affects carbon stocking
  >70 % of trees have lower recruitment with hunting

Question 10

what does the future of wildlife trade need to look like?

Answer 10

• need subsistence - work with people - find them better ways to get food - cant blame people with little money and little access to food
• trade needs to have more penalties in place