What to prioritise - species level

Question 1

Why prioritise?

Answer 1

Too many spp for equal attention
Different spp face different levels of threat - humans distributed unequally
More humans = more likely to be threatened
Not all species are equal

Question 2

Taxonomically unique species

Answer 2

More likely to pick the species with e.g. less in its genus

Sole family representative > conservation importance as show more GD and functional D

Question 3

Compare species taxonomy by…

Answer 3

D Distinctiveness = max branches from root/branches from root for spp
May’s distinctiveness = max descendants on path from root/descendants on path from root for spp
-measures shared nodes
Modify so consider branch length (how much unique evo history is preserved in that spp)
Future distinctiveness (relatives go extinct?)
Combine with abundance or rarity of spp
All need lots of phylo data !!

Question 4

Keystone species

Answer 4

Species keep the ecosystem intact - play keyrole
E.g. starfish removal from rock pool - was main predator and prevented other dominating
-drop from 15spp to 8
-clearly keystone - not just cos it was dominant though

Question 5

Measure keystone by…

Answer 5

Community importance index
change in community trait/change in focal spp biomass
If CI > 1 = keystone spp

Question 6

Keystone species limitations

Answer 6

Limited as only anecdotal evidence
If spp at risk - last thing you want to do is remove from habitat!
Making robust identification can therefore be difficult
Few key spp have same impact - but don’t make definition

Question 7

Umbrella species

Answer 7

Spp that needs large areas for conservation - others can be protected within this
Tends to be large verts
Saiga - 95% decline from 2 million !
Critically endangered
-protection of its habitat and hunting pressures
Protect others through this

Question 8

Flagship species

Answer 8

Charismatic spp promote conservation of habitat
Can be large or small areas
The panda for bamboo habitats
Problematic - if spp goes extinct, habitat = worthless
Diverts conservation from focal habitat

Question 9

Indicator species

Answer 9

Narrow ecological tolerance - only found in specific conditions
Helps to protect the individual habitat
If extinct, habitat = worthless
Species could go extinct due to other causes (e.g. plants effected by over harvesting)

Question 10

Rare and threatened species

Answer 10

Small geographic range size
Small population size
Habitat specialist
7 kinds of rarity based on this - requiring different conservation action

Question 11

Rare spp not threatened ?!?!?!?!?

Answer 11

Seychelles small day gecko
Has small geo range
Can have very large population sizes and survive out of its habitat
Normally in rainforest but survives in urban and agricultural land
-Showing problems with this strategy

Question 12

Common species go extinct ?!?!?!?!?!

Answer 12

Rocky Mountain grasshopper - likely to be due to loss of breeding ground
Passenger pigeon - 25-40% of North American birds, 3-5 billion individuals!
But still went extinct…

Question 13

Common species needing to stay common ?!?!?!?!?

Answer 13

American chestnut tree
Abundant to eastern seaboard, population destroyed (by 95%) by fungal pathogen
Leaves were nutrient rich and decayed rapidly - effecting the invert pop of streams
Importance of maintenance of population size - not just diversity

Question 14

Prioritising spp via extinction threat

Answer 14

Need to make a population viability analysis (PVA)
Based on detailed demographic data and how they vary with environment
Can see how likely extinction is
Requires lots of data - impractical

Question 15

IUCN Red list aims

Answer 15

Assign priorities and measure conserve progress
Consistent when used by different people
Improve objectivity through clear guidance
Facilitate comparisons across lots of taxa
Transparency to understand classification process

Question 16

IUCN categories

Answer 16

Gradual increasing risk

1. Critically endangered - extreme risk of extinction in wild
2. Endangered - very high risk of extinction in the wild
3. Vulnerable - high risk of extinction in the wild
4. Near threatened - close to qualifying

Question 17

IUCN points its based on

Answer 17

Range size
Population size
Number of populations
Severely fragmented populations
Population trend

Question 18

IUCN range size measurements

Answer 18

Uses either…
1. Extent of occurrence - the area within boundary range
2. Area of occupancy (AoO), occupied grid cells - not massively useful or representative
The two give different properties
Grid cell size is important for AoO

Question 19

IUCN Population size measurement

Answer 19

Number of mature individuals capable of reproduction
If breeding rates are bias - take into account
Reintroduced animals only included when bred successfully

Question 20

IUCN Number of populations

Answer 20

No. of distinct groups within little demographic or genetic exchange
Strict definition

Question 21

IUCN Severely fragmented populations

Answer 21

Small and found in isolated subpopulations

-often not enough data on links between populations

Question 22

IUCN Population trend

Answer 22

Over 10 years or 3 generations
-observed, inferred or suspected in past and predicted for the future (computer modelling for climate change can be used)
>50% decline and causes unknown, irreversible or continuing and over 10 years is seen as endangered

Question 23

EDGE species

Answer 23

Evolutionarily distinct and severely endangered

• merges IUCN and taxonomic distinctiveness
• applies a limit on groups of endangered species - like Albatross