Biology 1229

1
Biology 1229

• Extinction II
• The bad news

2
The four horsemen of the extinction crisis I
Habitat destruction

• Spoon-billed sandpiper
• Jamaican blackbird

3
Jamaican Blackbird

• Nesospar nigerrimus
• wildpine sergeant
• Endemic to Jamaica
• 2000-10000 remaining
• Mature montane, elfin and mist forest at high
  elevations

4
Blue and John Crow Mountains National Park

• 800 km2 of habitat protected
• Ongoing surveys to establish basic population
  biology of species
• Blue Mountain coffee
• 30/pound

5
Spoon-billed sandpiper

• Eurynorhynchus pygmeus
• Small wading bird
• Migratory
• 1000 2500 remaining
• Breeds annually
• 1 clutch replacement clutch
• 14 fledging rate

6
(No Transcript)
7
Saemangeum, South Korea

• Dammed in 2006 after lengthy legal battle

8
Spoon-billed sandpiper

• Threats
• Habitat destruction
• Breeding habitat
• Staging grounds
• Winter habitat
• Predation at breeding grounds
• Dogs
• Arctic foxes
• Predation at wintering grounds
• hunting

9
The four horsemen of the extinction crisis II
Overkill

• Example (some) fisheries
• Example Bushmeat

10
Fisheries as overkill
Fish
Invertebrates
11
Bushmeat

• The practice of eating wild animals
• aka game
• A serious problem, particularly in West Africa

12
Mountain Gorilla

• Gorilla beringei
• Critically endangered
• Central Africa, e.g. DRC
• 700 left
• None in captivity
• Population rising in 2002

13
Virunga Mountains

• DRC/Rwanda/Uganda
• 380 gorillas, population increasing
• Dian Fossey

14
Gorillas and bushmeat 2007

• Civil war in DRC leads to massive displacement,
  need for food and many people with guns designed
  for killing large primates
• Park rangers and anti-poaching patrols attacked
• Most rangers now pulled out of area
• 5 gorillas found shot dead in September
• Many more in bushmeat trade

15
Western lowland gorilla

• Double Whammy
• Bushmeat
• Ebola

16
The four horsemen of the extinction crisis III
Invasive species

• Mammals in New Zealand

17
Pre-human New Zealand

• 3 species of land mammals
• All predators were birds
• Good vision, poor sense of smell
• Many flightless birds

18
Then humans arrived
Ship rat
Kiore
Norway rat
Brush-tailed possum
House mouse
Feral pig
Stoat
ferret
Feral cat
weasel
European hedgehog
19
New Zealand extinctions since European settlement

• 57 land birds extinct since human arrival
• 19 since Europeans arrived

"there is very good reason to believe that the
bird is no longer to be found on the island, and,
as it is not known to exist anywhere else, it has
apparently become quite extinct. This is probably
a record performance in the way of
extermination." The Press 16 March 1895
Stephens Island wren Xenicus lyalli
20
Still endangered due (mainly) to predation

• Australasian Bittern
• Brown Kiwi
• Kokako
• New Zealand Dotterel
• Forbess parakeet
• Malherbes parakeet
• Chatham Island Oystercatcher
• Black Stilt
• Yellowhead
• Kaka
• Black Robin
• Kakapo
• numerous seabirds, invertebrates, frogs and
  reptiles

21
The four horsemen of the extinction crisis IV
Climate change

• Polar bear

22
Polar Bear

• Ursus maritimus
• Large carnivore
• Eats mainly seals
• Other terrestrial organisms will do
• Sexually dimorphic
• Semi-aquatic
• Arctic species

23
Polar bears are semi-marine

• Hunt mainly on sea ice
• Swim well (but not indefinitely!)

24
Climatic changes affecting polar bears

• Sea ice
• Decreased extent
• Longer swims for the first time, polar bears
  are being found drowned
• Timing of ice formation and breakup
• Results in mums in poorer condition and thus less
  reproduction
• Prey availability
• Increased human-bear interactions