Species Extinction

Question 1

Evil Quartet/HIPPO

Answer 1

Habitat Loss, Overexploitation, Introduced Species, Extinction, Pollution, Human Population and Overharvesting (Ceballos et al., 2017)

Question 2

climate change is a social issue

Answer 2

9/10 prescriptions are based on plants -> no ecosystem services will remain, yet these are essential to humanity

Question 2

extinction rate figures

Answer 2

From 1900 - 69 mammals, 80 birds, 24 reptiles, 146 amphibians and 158 fish went extinct (Ceballos et al., 2015)
177 different mammal species -> lost 40% of their range while ½ had lost 80% (1900-2015) (Ceballos et al., 2015).

Question 3

Anthropocene - sixth mass extinction (Barnosky et al., 2011)

Answer 3

-> in 100 years we lost 200 vertebrates, should have taken 10,000yrs = biological annihilation and species loss (Ceballos et al., 2017).

Question 3

Habitat Loss ->

Answer 3

transformation of the earth’s surface in a way which leads to the production of environments species can no longer tolerate -> biodiversity is being ordered and commericalised parts of the habitat.

Question 4

Overexploitation

Answer 4

species are often targeted for commercial value e.g. sharks for shark fin soup or bluefin tuna -> often leads to illegal purchasing -> or for health reasons e.g. 1/20 forest species in sub-Saharan Africa are at risk of overexploitation -> locals need to consume the organisms to meet protein requirements.

Question 5

Tipping points

Answer 5

soil exploitation -> lead to permanent environmental damage to the region preventing future regeneration (Lamb et al., 2005)

Question 6

Introduced species

Answer 6

evolutionary colonisation/globalisation led to species being introduced worldwide -> e.g. ballast water - ships introducing invasive species to new regions.

Question 7

Chains of extinction -> understudied region

Answer 7

one extinction of a species can lead to further extinctions e.g. passenger pigeon led to the extinction of the parasitic mite as they lived on the pigeons and e.g. northern pike in N. Scandinavia acting as a control on carpe populations (Bellard et al., 2019)

Question 8

Extinction of Oceania by the British

Answer 8

1800 bird species have been lost (Ceballos et al., 2015)

Question 9

Climate Change direct impacts

Answer 9

phenology-based changes (activity of species) -> range shifts -> using species-area relationship modelling = 15-37% of species to go extinct by 2050 (Thomas et al., 2004).

Question 10

Pollution

Answer 10

elemental pollution (N and K), eutrophication (limiting plant growth and causing anoxic dead zones as the algae bloom using all the O) -> no. of dead zones has increased overtime and is based across intensive agricultural systems e.g. eastern N.A.

Question 11

Drivers of extinction

Answer 11

interactions between C.C. impacts e.g. forest fires then lead to overhunting as the area is more vulnerable = does not lead to secondary succession as hunting limits recovery

Question 12

captive breeding -> problematic

Answer 12

can the species reacclimatise, have they been screened health wise, do diseases need to be removed from the environment -> farmers avoiding the use of herbicides as they may have wider negative impacts (Griffiths and Pavajeau, 2008)

Question 13

captive breeding example

Answer 13

Global amphibian crisis -> captive breeding as it is cheap since they breed rapidly -> 110 species considered -> 52 could not be reintroduced, of the 58 that were reintroduced 18 bred successfully but only 13 produced self-sufficient populations (Griffiths and Pavajeau, 2008)

Question 14

making captive breeding more effective

Answer 14

pilot programmes (Griffiths and Pavajeau, 2008)

Question 15

Insitu conservation

Answer 15

building fences and producing protected areas = change the behaviour of people who live within the regions -> private NGOs and predominantly the state has spearhead this -> 17% of the earth’s surface is currently a nature reserve

Question 15

de-extinction programmes - technofix solution

Answer 15

should not be concerned about extinction
taking elephant DNA working back to find the nucleotide differences with mammoths and then using elephants to breed them (Ceballos et al., 2017)

Question 16

insitu conservation controversy

Answer 16

violent dispossession of land from indigenous communities

Question 17

effectiveness of insitu conservation

Answer 17

ineffective for the scale of action/change required -> histories of them are controversial -> 0.01% of coral reefs actually protected -> 83% of plants likely to go extinct in New Caledonia are not in protected regions -> proposed that redevelopment could overcome these issues in Australia the plan would increase protection from 18 to 54 species (Fuller et al., 2010)

Question 18

insitu conservation example

Answer 18

Chagos Marine Protected Area -> Indian Ocean -> 2nd largest protected marine area (545,000km2) = biological resource for the UK

Question 19

coexistence conservation

Answer 19

matrix conservation without reserves -> modifying the landscape or land use practices to benefit humanity but not impact organisms/environment element of land sharing/sparing e.g. regrowing trees after deforestation but still have impacts (Putz et al., 2001)

Question 20

coexistence conservation examples (1)

Answer 20

reduced impact logging -> selective cultivation of individual trees = economic value but minimizes the no. of trees chopped/area = better protection biodiversity -> pick areas which will have lower biodiversity impacts, plan the direction of fall, reduce the need for deforestation for roads (Putz et al., 2001; Putz et al., 2008)

Question 21

coexistence conservation examples (2)

Answer 21

Agroforestry -> tropical rainforests -> involves incorporating species into the agricultural system (Schroth et al., 2004) -> can be conducted across a range of scales -> is effective leading to them holding 2/3 of the species in surrounding reserve regions – lots being saved (Bhagwat, 2008) -> allow species to move between remaining biodiversity sites (Philpott et al., 2008)

Question 22

plantations

Answer 22

Planting rapid, growth pioneer species -> maintain a canopy cover to protect the soil but facilitate secondary succession -> relies on native species being able to overturn fragmentation (Lamb et al., 2005).
2500 trees planted per hectare -> interspecific competition allowed to take place and produce a selective canopy cover -> more expensive -> used in the Central Amazon with 160 species planted over mining exhausted topsoil -> 130 yrs later the region has recovered (Lamb et al., 2005).
Plantations designed specifically to meet biodiversity demands -> prioritises ecosystem services (Lamb et al., 2005)

Question 23

Ethnoecology

Answer 23

hybrid ontologies e.g. Uluru-Kata Tjuta National Park -> Aboriginals using scientific methods to identify flora and fauna but using their protection methods (Stevens, 1997)

Question 24

Market-based approaches

Answer 24

utilitarian valuing -> commodification of the environment to save it -> contradictory in nature (McCauley, 2006)

Question 25

Finca Sante Fe, Costa Rica -> coffee plantation = native bees were ineffective decrease in yields by 60,000x -> coffee to pineapple cultivation -> no consideration for ecological impacts (McCauley, 2006)

Answer 25

Lake Victoria, Africa -> invasion of Nile with perch impacting biodiversity -> increased profits for fishermen so not considered a problem (McCauley, 2006)

Question 26

discourse on co2

Answer 26

biodiversity considered a secondary issue to lowering CO2 e.g. deforestation halted in Tanzania, Pemba Islands -> continued hunting of animals e.g. Pemba flying foxes (Caro and Mulder, 2016)

Question 27

market-incentives with local communities -> demand certain crops for higher value (Lamb et al., 2005)

Answer 27

Silviculture -> planting canopy shading trees with cash crops which mature -> native species being protected while economic incentives being produced (Lamb et al., 2005)

Question 28

Ecotourism

Answer 28

indigenous communities being financially independent -> brings in revenue -> focus is on people over the environment (Stevens, 1997)