Recent and Potential Future Impact of CC on Biodiversity Flashcards
Major threats to biodiversity at the moment
- Over-exploitation
- Agricultural activity
- Urban development
- Invasion and disease
- Pollution
- System modification
- Climate change
Maxwell et al 2016
CC effects a 1/4 of species over exploitation does however, strong possibility it could become dominant
CC extinctions
Golden toad 1989
Costa Rica Cloud Forest
1989
Drying of forest due to el nino event
Bramble Cay Melomys
2009
CC induced sea level rise and extreme storm events flooded entire island
Short term extreme event enough
How can we see how species have reacted to CC in the past
Fossil and pollen records
eg after last glacial period
Oaks started to colonise out of refugee, then beech (more limited dispersal ability)
Current climate change at unprecedented rate
Recent species changes due to CC
Grey whales in Mediterranean formerly only in california but now ice caps melting there is a route through
UK colonists- purple heron, little bittern
Dartford Warbler moving up
Not just range shifts but abundance changes too
Comma butterfly was limited to small area in S Wales thought due to CC and change in food source it rapidly expanded its distribution and now up to scotland
What is a species distribution model
Try and relate climate data to species distributions (typically omit much biology such as could a app disperse there) also assumes climate is a key driver of distributions
Can look at rainfall, temperature, growing degree days,
Point data to see current distributions and polygon range outlines
Issue is where more biodiversity is they tend to be poorer countries and so have fewer weather stations so we have less data about important climates
Furthermore current data sets quite variable. Temp data can be quite consistent but ppt hugely variable –> makes predictions harder. Even current models hugely varied - Baker et al 2016
What is an Indicator
A group of species who weighted population trends (when taken together) reflects the average behaviour of the constituents spp group.
Some incr under cc some decr
Could see if spp already being affected eg farmland birds seen to be decreasing
primarily arctic spp in the uk doing less well
Mediterranean doing better
They projected some over the EU and USA
In EU spp predicted to do better haven’t been changing much. But declining are declining
In US those expected to do worse haven’t change and better are increasing,
The gap between the 2 groups is quite similar. CC happening now
Which 2 butterflies are reacting differently to CC
Comma- high mobility, generalist, tracking climate
Silver studded blue- low mobility, habitat specialist, restricted in area of apparent suitable climate
SDM for endemic bird richness in albertine rift valley
East Africa 14 endemic spp
Likely to have to shift to higher evlations to follow nicee and retreat North up the valley
By 2085 huge areas will have disappeared of appropriate habitat. Massive loss in app richness in many areas. One big mountain of the mountains of the moon remains biodiverse throughout the period. So if you want to protect somewhere, protect here.
Baker et al 2015
Species in Africa
Our results suggest that climate change has the potential to severely impact regional fauna and to reduce the effectiveness of the PA network to conserve the region’s biodiversity.
Using a region- ally appropriate, dynamically downscaled ensemble of climate projections, which captures both large-scale (e.g. West African Monsoon) and local climate regimes, we have attempted to reduce the uncertainty associated with projec- tions across climatically complex regions.
Our results indicate that there is considerable spatial heter- ogeneity in projected impacts, both within and between taxo- nomic groups, with the average severity of projected impacts and their uncertainty increasing towards the end of century.
The climatic conditions pre- dicted for single grid cells are representative of the mean climate expected in a cell, but cannot capture the finer-scale climatic variability.
A frequent problem for multitaxa analyses conducted across broad spatial scales and at relatively coarse resolutions is the inevitable omission of species with small range extents that are difficult to model due to a paucity of data.
(1) adaptation planning should primarily consider early-, and possibly mid-, century impact projec- tions in order to have most confidence in species responses (Chapman et al., 2014) and (2) future studies of climate change impacts should incorporate a broad suite of species and use multiple approaches to balance biases present in dif- ferent approaches (e.g. correlative, trait-based, expert opin- ion)
Substantial species turnover across the network is projected for all three taxonomic groups by 2100 (amphibians = 42.5% (median); birds = 35.2%; mammals = 37.9%),
Adaptive management using species turnover
That colourful pictures
Can apply these colours to areas see how species turn over
Often specially aggregated (especially for IBA in Africa)
Congo has regions of high stability- can continue to manage as is
Sites of high turnover (eg Botswana) may benefit from increasing connectivity
May have to translocate some species in anthropogenic sources blocking movement or bad dispersers
In South America lots of areas have high turnover - especially Amazon
Can plot for spp across africa and suggest wider management strategies
can also look at projected range alterations to see the areas with the highest numbers of species moving through them
Can also stack predictions of range changes for many species typical of a particular habitat to show how entire communities may shift
What are adaptive management strategies under CC
Adaptive management is a systematic approach
for improving resource management by learning from management outcomes. An adaptive approach involves exploring alterna- tive ways to meet management objectives, predicting
the outcomes of alternatives based on the current state
of knowledge, implementing one or more of these alternatives, monitoring to learn about the impacts of management actions, and then using the results to update knowledge and adjust management actions (15). Adaptive management focuses on learning and adapting, through partnerships of managers, scientists, and other stake- holders who learn together how to create and maintain sustainable resource systems (3).
Adaptive management strategies urgently required bc substantial disruption predicted with cc
Broad range of tools
- protect key ecosystem features
- reduce anthropogenic pressures
- restoration
- translocation
Management can be aimed at enhancing system persistence or promoting system transformation
IBAs in SE Asia
Much more diverse than africa
Adjoining areas have different patterns of turnover making generalising management strategies more difficult. Sea level rise effects this area too. Intertidal and salt marsh habitats likely affected- may want to push PA further inland
Can use fine scale distribution data to model specific regions eg albertine rift valley
What is a vulnerability assessment
Circle picture
Foden et al 2013
As an alternative to SDM models, Foden et al. (2013) propose assessing species according to their exposure, adaptive capacity and sensitivity to climate change.
Could be combined with SDMs to produce refined risks for many species that also consider species traits.
What are potential mitigation measures?
- Identify key stable sites- refugia- sites that retain the complement of species they currently support and/or are able to support other spp that disperse into them as range shifts eg areas of highly variable topography such as mountains eg cameroon highlands
- Variable buffer zones around PAs- as ranges begin to shift they could move into buffer areas which could then be upgraded to full protection. Also reduce edge effects and human disturbance. Useful in short/medium term but unlikely practicable for many spp/PAs in long term due to magnitude of potential range shifts. Could be used with 3
eg Rudd’s alpacas expected to shift >750 km between now and 2080 - too big for buffer
- Stepping stones- unconnected areas of preserved or restored habitat allowing for movement between PA through unsuitable habitat or over places too large for no stop dispersal.
eg Gabela’s helmet shrike shifting SE would benefit from stepping stones between IBAs - Species translocations- transport and/or release of wild /CB individuals to the sites deemed suitable. Where new pops can be established.
- creation of non-analog communities?
- a lot of species may need this. possible?
eg great bustard introduced to UK where it hasn’t bred for 200 years to re-establish new population. It bred for the first time a few years ago. To date, reintroductions are generally where a species has been in the past and now no longer persists.
Assisted colonisation example
Translocating a species threatened by CC
Marbled White Butterfly
Poor dispersal ability (1km/yr).
Introduced pop to suitable area beyond species dispersal capacity.
The pop at wingate quarry has persisted and expanded at rates similar to natural colonisations.
Distribution of introduced pop grew from 7.2ha–> 17.8ha
Model predicted where it could persist and was right
After 9 years still persisting and expanding- climate models providing useful info about individual spp
Can then do retrospective analysis to see if we could’ve predicted what happened
176 instances of butterflies being released into novel areas (planned and unofficial)
Used climate envelope to simulate climate suitability in successful (present for more than 10 years) and unsuccessful sites
Suitability at successful sites was almost double that at sites of failed releases
