Starter Write down four factors that you think will make a species more prone to extinction. Think about endangered species that you know and species that you know have gone extinct.

Learning outcomes You should be able to: – Describe and explain the factors that may make species more or less prone to extinction. – Outline the factors used to determine a species’ Red List conservation status. – Look at the command terms… what do they mean? – So what would you need to be able to do to achieve this outcome?

Different characteristics make species more / less vulnerable to extinction… Golden lion tamarin tamarin-saved-from-extinction Narrow geographical range Small population size / declining numbers “Lonesome George” – Pinta Island giant tortoise A large body Tiger Low reproductive potential Humpback whale Specialised feeders, niche requirements Panda Hunting The now extinct Thylacine

Read the article The article gives lots of different characteristics that can cause extinction. Read what it has to say and complete the table as you go.

IUCN Red List International Union for the Conservation of Nature The Red List is an inventory of all threatened species. The main purpose of the list is to highlight plants and animals facing a higher risk of global extinction than others. Various factors are used to determine the conservation status of species: Population size Reduction in population size Members of mature individuals Geographic range and degree of fragmentation Quality of habitat Area of occupancy Probability of extinction

Evaluation criteria For the species that have been evaluated and where there is enough data, the following criteria are used: – Extinct – Extinct in the Wild – Critically endangered – Endangered – Vulnerable – Near Threatened – Least Concern Threatened

Some of the species on the list… The Black Rhinoceros (Diceros bicornis) Critically Endangered. Its population has declined by an estimated 97.6% since 1960, with numbers bottoming out at 2,410 in 1995, mainly as a result of poaching. Since then, numbers have doubled to 4,880 by the end of Current numbers are however still 90% lower than three generations ago. Photo © Steve Garvie, bicornisSteve Garvie Described in 2010, the Caquetá Tití Monkey(Callicebus caquetensis) has been assessed for the first time in 2012 as Critically Endangered. It is endemic to eastern Colombia, and occurs in an area subject to intense human colonization that has caused widespread habitat destruction and fragmentation. Photo © Javier GarciaCallicebus caquetensisJavier Garcia Previously thought to be extinct, the Hula Painted Frog (Discoglossus nigriventer) of Israel was rediscovered in The Huleh marshes were drained in the 1950s in an attempt to both eradicate malaria and to make the land suitable for agricultural use. The remaining wetland (5% of the original area) was set aside as the Hula Nature Reserve in The reserve is well-managed but functions as a refuge for many water birds; predation by birds is thought to be a real threat to the small population of this frog. In addition, most of the surrounding area is cultivated. This frog is now listed as Critically Endangered. Photo ©Oz Rittner, TAU - Zoological Museum, Steinhardt National Collections of Natural History, IsraelDiscoglossus nigriventerOz Rittner, TAU - Zoological Museum, Steinhardt National Collections of Natural History, Israel

Checking outcomes List 5 characteristics that make a species more vulnerable to extinction. Explain why these characteristics increase vulnerability to extinction. List the characteristics that are used to determine the conservation status of a species.

Activity – in pairs Choose 3 species of your choice: – One that has become extinct – One that is critically endangered – One whose conservation status has been improved by intervention Research the case histories of your species: – You should find out: The socio-political, ecological and economical pressures that caused / are causing the chosen species’ extinction. The ecological roles of each species and the consequences of their disappearance. Be ready to present the information in the next class.

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A natural area of biological significance that is threatened… Stretches 2300 kilometres and is home to 1500 species of fish, 359 types of hard coral, a third of the workld’s soft coral, 6 of the world’s 7 species of threatened turtle and more than 30 species of marine mammal. Human threats Tourism – people take bits of coral as souvenirs Over-fishing – disrupts the balance of species Seafloor trawling – destruction of seafloor. Soil run-off – inorganic nitrogen pollution has increased by 3000% Sedimentation – mud pollution Global warming – increase insea temperatures Natural threats Crown-of-thorns starfish – feeds on polyps Storms and cyclones El Niño

Homework Research and write about an area of biological significance that is under threat from human activity: Identify why it is an area of biological significance Identify the human threats and natural threats affecting the area. Identify what is happening and use the Great Barrier Reef example to help you.