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1

Why prioritise conservation efforts?

- ideally would protect everything but non pragmatic to divide attention equally between all species

- humans are unevenly distributed, species near dense human populations experience more threats

- some species are more sensitive

2

What are the four main ways of setting conservation priorities?

- taxonomically unique species
- keystone species
- umbrella/flagship/indicator species
- rare/threatened species

3

What is taxonomic distinctiveness?

- formalised by Vane-Wright (1991)
- Distinctiveness (D) = max branches from the root / the number of branches from root for species

- modifications added

- May's distinctiveness: max number of descendants on the path from the root / number of descendants on the path from the root for the species

- terminal branch length

- future distinctiveness

- combine w other metrics like abundance

4

Why use to taxonomic distinctiveness to set priorities? Difficulties?

- sound and intuitive principle
- sole family representatives have greater conservation importance as represent more genetic (and often functional) diversity

BUT

- requires detailed taxonomic knowledge
- only works for some groups

5

Taxonomic distinctiveness example:

- kagu vs green-backed white-eye

- both kagu and green-backed white-eye endemic to new caledonia

- BUT

- kagu only member of Rhynochetidae genus
- green-backed white-eye from genus with 75 species (Zosterops)

6

What is a keystone species?

- species whose impact on the community is large and large relative to their biomass i.e not just dominant species

- Community important index (CI): change in community trait/change in focal species biomass
- CI > 1 = keystone species

7

What is an example of a keystone species?

- starfish

- upon removal of starfish system collapsed from 15 - 8 species
- starfish are predators that prevent competitive dominance & exclusion at lower trophic levels

8

What are the problems with using keystone species to set priorities?

- limited in use assigning priorities
- many keystone species only identified anecdotally
- robust identification difficult, often requires removal experiments
- a few non-keystone species can have same significance as one keystone species

9

What are umbrella/flagship/indicator species?

- all share basic concept that protecting a single species will help protect others
- characteristics of focal species differ

10

What is an umbrella species? Example?

- species that require large area for conservation
- protect other species with similar habitat requirements
- tend to be large vertebrates

e.g. endangered Saiga antelope
- declined 95% between 1950 and 2010
- critically endangered
- shared threat with other species: habitat destruction

11

What is a flagship species? Example?

- charismatic species used to promote conservation of a region/habitat
- can require small or large areas
- e.g. seahorse home range of 10m2

12

What are problems with flagship species driven priorities?

- useful concept
BUT
- can divert resources away from more effective conservation species for focal habitat
- implies focal habitat is worth less without focal species

13

What is an indicator species?

- species with narrow ecological tolerance
- therefore found only under certain set of conditions
- help to protect indicated habitat
- no specific area requirement

14

How useful is setting priorities by umbrella/flagship/indicator species?

- important concepts
- facilitate conservation but not problem free
- used in isolation will not generate adequate protection of other species

15

What is a rare species?

- Rabinowitz 1981: there are 7 different kind of rarity
- relate to intersections between geographic range size, habitat specificity and population sizes

- some species are naturally rare
- different types of rarity requires different conservation action
- rare species aren't always threatened

16

What is an example of a non-threatened rare species?

- Seychelles small day gecko
- endemic and v small geographic range
BUT
- 50,000 individuals, v high density
- can survive in agricultural and urban areas as well as natural rainforest habitat

17

What are examples of a common species becoming extinct?

- rocky mountain grasshopper
- went from abundant to extinct within 30 years, probably due to loss of breeding habitat

- passenger pigeon
- 3-5B individuals when europeans discovered america circa 1500
- 25-40% north american birds
- extinct in 1914

18

Why protect common species?

- american chestnut

- functionally important
- not exempt from extinction

- american chestnut
- nutrient rich leaves decay rapidly
- was abundant on eastern seaboard
- fungal disease decimated population by 95%
- majorly altered nutrient cycling and freshwater invertebrate assemblages

19

How are species prioritised by extinction threat?

- population viability analysis

Ideal: Population Viability Analysis (PVA)
- based on detailed up to date demographic data: population size, birth rate, death rate, how these vary with environment
- impractical for most species

20

How are species prioritised by extinction threat?

- IUCN red list

- International Union for the Conservation of Nature
- started in 1960
- 40,000 species now assessed
- all birds, mammals & amphibians & partial assessments for other taxa
- global assessments underway for fish, corals, and plants

21

What are the aims of the IUCN red list?

- classify threats to assign priorities & measure conservation progress
- consistent when used by different people
- improve objectivity through clear guidance
- facilitate cross-taxa comparisons
- transparency: give people using the lists a better understanding of the classification process

22

What are the IUCN red list categories?

- evaluated or non evaluated

if evaluated
- adequate data vs data deficient

if adequate data
- extinct, extinct in the wild, threatened, near threatened, least concern

if threatened
- critically endangered, endangered, vulnerable

23

What do the IUCN threat categories mean?

critically endangered
- extremely high risk of becoming extinct in the wild

endangered
- very high risk of becoming extinct in the wild

vulnerable
- high risk of becoming extinct in the wild

near threatened
- close to qualifying for above, or likely to qualify for above in near future

24

What are IUCN evaluations based on?

- range sizes


- population sizes
- number of populations: number of distinct
groups with little demographic or genetic exchange
(less than one individual/gamete per generation)

- whether populations are severely fragmented: severely fragmented populations - most
individuals found in small and relatively isolated
subpopulations


- trends in the population

- whether populations fluctuate extremely

25

What are the difficulties associated with identifying range size for the IUCN redlist?

- extent of occupation (area within range boundary) vs area of occupancy (occupied grid cells)
- measure different properties
- area of occupancy varies with spatial scale

26

What are the difficulties associated with identifying population size for the IUCN redlist?

- population size: number of mature individuals capable of reproduction
- but sex ratio/biases must be considered
- reintroduced individuals only counted after having successfully bred

27

What are the difficulties associated with identifying population number/fragmentation for the IUCN redlist?

- typically has to use habitat distribution data as little information on links between populations

28

What are the difficulties associated with identifying population trend for the IUCN redlist?

- over ten years or 3 generations

- observed, inferred or suspected in the past OR
predicted in the future

- e.g. endangered if decline > 50% and causes
unknown, continuing or not reversible

- often no direct data on population trend

- can use data on trends in habitat loss – if good
data on habitat selection available

29

What are EDGE species?

- evolutionarily distinct and endangered
- priority