Biology 1229 Extinction II: The bad news

The four horsemen of the extinction crisis I: Habitat destruction  Spoon-billed sandpiper  Jamaican blackbird

Jamaican Blackbird  Nesospar nigerrimus  ‘wildpine sergeant’  Endemic to Jamaica  remaining  Mature montane, elfin and mist forest at high elevations

Blue and John Crow Mountains National Park  800 km 2 of habitat protected  Ongoing surveys to establish basic population biology of species  Blue Mountain coffee ~$30/pound…

Spoon-billed sandpiper  Eurynorhynchus pygmeus  Small wading bird  Migratory  1000 – 2500 remaining  Breeds annually 1 clutch + ‘replacement clutch’ 14 % fledging rate

Saemangeum, South Korea  Dammed in 2006 after lengthy legal battle

Spoon-billed sandpiper  Threats Habitat destruction  Breeding habitat  Staging grounds  Winter habitat Predation at breeding grounds  Dogs  Arctic foxes Predation at wintering grounds  hunting

The four horsemen of the extinction crisis II: Overkill  Example: (some) fisheries  Example: Bushmeat

Fisheries as overkill… Fish Invertebrates

Bushmeat  The practice of eating wild animals  aka ‘game’  A serious problem, particularly in West Africa

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

Virunga Mountains  DRC/Rwanda/Uganda  380 gorillas, population increasing  Dian Fossey

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

Western lowland gorilla  Double Whammy Bushmeat Ebola

The four horsemen of the extinction crisis III: Invasive species  Mammals in New Zealand

Pre-human New Zealand  3 species of land mammals  All predators were birds Good vision, poor sense of smell Many flightless birds

Then humans arrived… Kiore House mouse Ship rat Norway rat Feral cat Feral pig Stoat ferret weasel Brush-tailed possum European hedgehog

New Zealand extinctions since European settlement  57 land birds extinct since human arrival  19 since Europeans arrived Stephen’s Island wren Xenicus lyalli "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

Still endangered due (mainly) to predation  Australasian Bittern  Brown Kiwi  Kokako  New Zealand Dotterel  Forbes’s parakeet  Malherbe’s parakeet  Chatham Island Oystercatcher  Black Stilt  Yellowhead  Kaka  Black Robin  Kakapo  + numerous seabirds, invertebrates, frogs and reptiles

The four horsemen of the extinction crisis IV: Climate change  Polar bear

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

Polar bears are semi-marine  Hunt mainly on sea ice  Swim well (but not indefinitely!)

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