Threatened Species WALT: Identify what causes species to become extinct STARTER: Write down as many ways you can think of about how we can re-build populations of animals or plants that have become low

Biodiversity Total number of species = 1.66 million

Things that can cause extinction New competitors Disease Hunting Why Animals Become Extinct Pollution New predators Climate change e.g. An ice age Destruction of habitats

Human activity: logging The Western Gorilla (Gorilla gorilla) was uplisted from Endangered to Critically Endangered in 2007 after the Western Lowland Gorilla (G. g. gorilla) subspecies, suffered a population decline of more than 60% since the early 1980s. Hunting and deaths caused by Ebola were the main causes of this decline and both these threats continue to affect the Western Lowland Gorilla population. Sumatran Orangutan (Pongo abelii) is listed as Critically Endangered. Endemic to the island of Sumatra in Indonesia, this ape has suffered a population decline of more than 80% over the last 75 years. The species is seriously threatened by logging (both legal and illegal), wholesale conversion of forest to agricultural land, and oil palm plantations, and fragmentation by roads. Disease Human activity: logging The Polar Bear (Ursus maritimus) is classed as Vulnerable. Recent modelling of the trends for sea ice extent, thickness and timing of coverage predicts dramatic reductions in sea ice coverage over the next 50 to 100 years due to global climate change. It is suspected that there will be a population reduction of at least 30% over the next 45 years as a result of this habitat loss and declining habitat quality Atelopus varius is a Critically Endangered harlequin toad that was once abundant in Costa Rica and western Panama. Declines began at Monteverde in 1988, and by 1996 it was believed to be extinct in Costa Rica. The cause of its decline is possibly a result of the fungal disease, chytridiomycosis. Disease Loss of ice - habitat

Lonesome George - Galapagos Islands Watch the clip (8 mins) about George. Write down 5 points about how his habitat was lost and what happened. https://www.youtube.com/watch?v=i2CQ9PyktOM

What will be the problems from this ‘solution’? Introduction of new predators: the case of the Chatham Island Black Robin: Lives on islands near NZ Only 7 left in 1976 Cats took over the island and the birds could not escape the predators Conservation programme was set up – other birds used as foster parents for the chicks There are now 250 birds – all descendents of 1 breeding pair What will be the problems from this ‘solution’?

Chatham Island Black Robin - Problems Island habitat is too small – some birds are having to be moved to other islands All from one set of parents – very little genetic variation. This means the birds will be vulnerable to environmental changes or diseases More competition with other birds on other islands Higher Only

Habitat destruction: the case of the Orangutans of Borneo

Use the orangatans news article answer the questions What is the habitat of the Orangutans? How long will it take for the Orangutans to lose their habitat, in Borneo according to UNEP? How many wild Orangutans are there currently? Which other species are also threatened because of the habitat loss? What are the reasons for the orangutan numbers going down? Write down the main uses of the rainforest for humans. 98% of the rainforest might be gone in how many years? What percentage of logging in Indonesia is illegal? Who / what is it that is carrying out the logging? What are seen as barriers to preventing the illegal logging? How many rangers patrol 35 of Indonesia’s parks? What can you do, as someone who buys palm oil or wood products, to ensure you don’t buy from those companies that are working illegally? What do you think the author meant when he said “the international community must join the battle”?

Why should we care about conserving species? The main reasons given for conserving species are Economic – provide us with e.g. food, fuel, tourism money Ecological – to keep the ecosystem in balance, plants take in CO2 and release oxygen Ethical – all living things have a right to survive Aesthetic – humans enjoy observing wildlife

Ways of conservation: Designated protected areas Zoos Botanical gardens – grow seeds in protected area Captive breeding

Captive breeding programmes Advantages of captive breeding programmes Fewer animals need to be caught in the wild Reduces the chances of extinction Reintroduction into the wild Problems with captive breeding programmes After release Too tame or too used to captivity to survive Difficulties in finding food The original threat is still there Inbreeding depression