1
Percentage of Durrell species under threat Total score for this threat on all species currently Projected future score for this threat on all species Invasive species Threat score 0 1000 Climate change and storms Logging,wood harvesting and huntung Fires Habitat loss via agriculture Human disturbance Volcanoes and earthquakes Pollution Urban development 75 58 50 48 Top 10 species under highest threat The Mountain Chicken is a giant frog found only in Dominica and Montserrat in the Caribbean. It faces a jaw-dropping number of threats, many of which have had a severe impact on its population. Forest loss, over-hunting, predation by invasive rats, volcanic eruptions, pollution and now a catastrophic disease called chytridiomycosis, responsible for wiping out tens of amphibian species over the past couple of decades, have taken their toll. The Mountain Chicken’s future is very uncertain and it needs all the help we can muster. Mangrove Finch 10 Madagascar Pochard 09 Echo Parakeet 08 White-breasted Thrasher 06 Lesser Night Gecko 05 Orange-tailed Skink 04 Bojer’s Skink 03 Monrserrat Galliwasp 02 Antiguan Racer 07 Mountain Chicken 01 42 25 17 What are the biggest threats to Durrell’s target species today? How are these threats likely to change? #02 Threats to species survival 25 90 This indicator identifies the most important threats to Durrell’s 50+ target species today, the relative impact of these threats and how they are likely to change in the future. Durrell’s field staff assess every threat to their target species and, for each, score its timing (past, continuing, future), scope (proportion of the population affected) and severity (size of declines caused by the threat) on a scale of 0-3. The sum of scores across the range of threats gives the overall ‘threat score’ for each species, allowing us to rank them in order of threat level. Currently the Mountain Chicken, Montserrat Galliwasp and Bojer’s Skink face the highest threat levels. The biggest threat by some distance comes from invasive species – animals or plants that have been introduced by humans and spread rapidly, having negative and sometimes catastrophic impacts on the native species. Not only is the score for this threat greater than all the other categories put together, with more than 90% of our target species affected, worryingly it is predicted to increase in the future. Loss of the forest and wetland homes of our target animals through agriculture and logging, and direct hunting of some species are the next biggest threats. This indicator helps Durrell to identify the actions, knowledge and skills required to conserve target species and make long-term decisions on where conservation needs to be stepped up to deal with a changing world.

Durrell Index Threat to Species

Embed Size (px)

DESCRIPTION

Durrell Index, Threat to Species

Citation preview

Percentage of Durrell species under threat

Total score for this threat on all species currently

Projected future score for this threat on all species

Inva

sive

sp

ec

ies

Thre

at

sco

re

0

1000

Clim

ate

ch

an

ge

an

d s

torm

s

Log

gin

g,w

oo

dh

arv

est

ing

an

d h

un

tun

g Fire

s

Ha

bita

t lo

ss v

iaa

gric

ultu

re

Hu

ma

nd

istu

rba

nc

e

Vo

lca

no

es

an

d e

art

hq

ua

kes

Pollu

tion

Urb

an

de

velo

pm

en

t

75

58

50

48

Top 10 species under highest threat

The Mountain Chicken is a giant frog found only in Dominica and Montserrat in the Caribbean. It faces a jaw-dropping number of threats, many of which have had a severe impact on its population. Forest loss, over-hunting, predation by invasive rats, volcanic eruptions, pollution and now a catastrophic disease called chytridiomycosis, responsible for wiping out tens of amphibian species over the past couple of decades, have taken their toll. The Mountain Chicken’s future is very uncertain and it needs all the help we can muster.

Mangrove Finch10

Madagascar Pochard09

Echo Parakeet08

White-breasted Thrasher06

Lesser Night Gecko05

Orange-tailed Skink04

Bojer’s Skink03

Monrserrat Galliwasp02

Antiguan Racer07

Mountain Chicken01

42

25

17

What are the biggest threats to Durrell’s target species today? How are these threats likely to change?

#02 Threats to species survival

25

90

This indicator identifies the most important threats to Durrell’s 50+ target species today, the relative impact of these threats and how they are likely to change in the future.

Durrell’s field staff assess every threat to their target species and, for each, score its timing (past, continuing, future), scope (proportion of the population affected) and severity (size of declines caused by the threat) on a scale of 0-3. The sum of scores across the range of threats gives the overall ‘threat score’ for each species, allowing us to rank them in order of threat level.

Currently the Mountain Chicken, Montserrat Galliwasp and Bojer’s Skink face the highest threat levels.

The biggest threat by some distance comes from invasive species – animals or plants that have been introduced by humans and spread rapidly, having negative and sometimes catastrophic impacts on the native species.

Not only is the score for this threat greater than all the other categories put together, with more than 90% of our target species affected, worryingly it is predicted to increase in the future.

Loss of the forest and wetland homes of our target animals through agriculture and logging, and direct hunting of some species are the next biggest threats.

This indicator helps Durrell to identify the actions, knowledge and skills required to conserve target species and make long-term decisions on where conservation needs to be stepped up to deal with a changing world.