principles of conservation biology an overview
Download
Skip this Video
Download Presentation
Principles of Conservation Biology: an Overview

Loading in 2 Seconds...

play fullscreen
1 / 48

Principles of Conservation Biology: an Overview - PowerPoint PPT Presentation


  • 360 Views
  • Uploaded on

Principles of Conservation Biology: an Overview. Prof. Claire Kremen Univ Cal Berkeley Cal Academy Bioforum Apr 4, 2009. Biodiversity Defined.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Principles of Conservation Biology: an Overview' - DoraAna


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
principles of conservation biology an overview

Principles of Conservation Biology: an Overview

Prof. Claire Kremen

Univ Cal Berkeley

Cal Academy Bioforum

Apr 4, 2009

biodiversity defined
Biodiversity Defined
  • “Biodiversity is the total variety of life on earth. It includes all genes, species and ecosystems and the ecological processes of which they are a part” (Convention on Biodiversity, 1992)
ecological interactions
Ecological interactions
  • Biodiversity is more than the sum of the parts
  • Interactions “structure” communities, maintain diversity, and make ecosystems work
  • e.g. Competition
  • Predation
  • Mutualisms (e.g. pollination, seed dispersal)
evolution and extinction
Evolution and extinction
  • Biodiversity is not static but constantly changing
  • 99% of the species that ever lived have gone extinct
    • Mass extinctions
    • Background extinctions
    • Finite lifetimes
conservation biology
Conservation biology
  • Concerned with loss of biodiversity, not just loss of species
    • “Fundamental loss of resources in genetics, species, community attributes and ecosystemproperties”
    • Flip side: maintenance of biodiversity, ecological and evolutionary processes
why care about biodiversity
Why care about biodiversity?
  • Intrinsic value (Muir, 1838-1914)
    • All species have value independently of their utility to humans
  • Utilitarian value (Pinchot, 1865-1946)
    • Species that provide the “greatest good to the greatest number” (over the longest time) have value
  • Cons Bio : (Leopold, 1886-1948)
    • can include both value systems
    • “To keep every cog and wheel is the first precaution of intelligent tinkering" (Leopold 1943).
aldo leopold 1886 1948 evolutionary ecological land ethic
Aldo Leopold (1886-1948)Evolutionary-Ecological Land Ethic

Biological communities: assemblages of interdependent species

Maintaining the health of natural ecosystems and ecological / evolutionary processes

Humans exist within the ecological community; depend on ecosystem services

Synthetic approach:

Both intrinsic value and utilitarian value

why be concerned about biodiversity loss if extinction is a fact of life
Why be concerned about biodiversity loss if extinction is a fact of life?

Moderate certainty: current extinction rates > by 100 – 1000 times

10 – 30 % of mammals, birds and amphibians threatened

Is extinction outpacing speciation potential?

threats to terrestrial species
Threats to terrestrial species
  • Terrestrial habitat loss
  • 39-50% of land surface transformation
result of habitat loss
Result of habitat loss
  • Reduction in total area  decrease in size, # of populations  local extinctionsfewer species
  • Reduction in habitat diversity
    • Reduced species diversity
    • Cascading effects, co-extinctions
habitat fragmentation

The forested areas of Warwickshire, England

From Primack 2002

Habitat fragmentation
  • Above and beyond habitat loss
  • Isolation: reduced immigration, re-colonization
  • Edge effects
invasion
Invasion

The distribution of species on Earth is becoming more homogenous

The rate of invasion is increasing over time

HOMOGENIZATION

Growth in Number of Marine Species Introductions in North America and Europe

introduced cheatgrass bromus tectorum has transformed the great basin shrub steppe ecosystem
Introduced cheatgrass, Bromus tectorum, has transformed the Great Basin shrub-steppe ecosystem
  • Has increased fire frequency from once/80 years to once/4 years!
  • Occupies over 5 million hectares of Great Basin
climate change effects on biodiversity
Climate change effects on biodiversity
  • Range shifts
    • Latitudinal range
    • Altitudinal range
  • Mis-matched interactions
  • Reassembled (scrambled) communities
  • Feedbacks (e.g. vegetation and climate)
  • Species Endangerment
climate change endangers polar bears
Climate change endangers polar bears
  • Sea ice is the key
    • Bottom up: habitat for micro-algae
    • Top down: seal hunting ground; corridors to dens
  • Loss of sea ice  endangers polar bear
  • Loss of top predator: cascading effects on Arctic food web
climate change can induce coral reef bleaching
Climate change can induce coral reef bleaching

http://www.ogp.noaa.gov/misc/coral/98bleaching/

Bleached and normally pigmented Pocillopora colonies

oceans and freshwater aquatic habitats
Oceans and Freshwater Aquatic habitats
  • If anything are more vulnerable to same threats, with enhanced vulnerability to over-exploitation and pollution
  • Freshwater
    • USA: Very high endangerment levels in fish & amphibians (25-40%) and crayfish & molluscs (> 60%) compared to terrestrial vertebrates (15-18%
over exploitation of global ocean fisheries

Botsford 1997

Over-exploitation of global ocean fisheries
  • > 60% of the world’s fisheries are fully to over exploited, or depleted
  • By-catch increases fish-catch by 30%
conserving biodiversity
Conserving biodiversity
  • Genetic level: seed, egg, sperm banks
  • Population and species level – science of managing small populations
    • Captive breeding (zoos/botanical gardens)
    • Reintroductions
    • Population management in the wild
      • Protection (hunting, disease, habitat)
      • Genetic management (translocations)
      • Habitat restoration
conserving biodiversity habitat species ecosystem level
Conserving biodiversity: habitat, species, ecosystem level
  • Protected areas
  • Managing the matrix
    • Restoration
    • Wildlife-friendly agriculture
protected areas for biodiversity conservation
Protected areas for Biodiversity Conservation
  • Select the areas that represent and maintain biodiversity over time…

(Margules and Pressey 2000)

representation
REPRESENTATION

Including as many different ecosystems and species in the reserve network

Representing the full range of variation (genetic, ecological) present within target species

reserve design decision support
Reserve Design Decision-Support
  • Computer programs
  • Meet conservation targets (e.g. conserve 20% of each habitat type and 3 populations of each species) at least cost
a network of reserves that represents species efficiently
A network of reserves that represents species efficiently
  • But it may not be so good at maintaining biodiversity – why not?

Site selection in the Sierra Nevada foothills for conservation prioritization

Grey = already protected

maintaining biodiversity over time
Maintaining biodiversity over time
  • Population persistence (viability)
  • Maintaining ecological processes
    • E.g. migrations
  • Maintaining evolutionary processes
    • Potential for adaptation within populations (genetic diversity)
    • Selecting areas where rapid speciation is occurring
  • Response to climate change
slide28

Reserve design features for persistence

SIZE

Edge to area ratio

Disturbance regime

Shape

Environmental gradients

Functional units

Corridors

Matrix habitat

CONNECTIVITY

slide29
SIZE

Larger size 

  • More species (interactions, functions), S-A relationship
  • More habitats (interactions, functions)
  • Larger populations –
  • Protects vulnerable species
    • Area demanding: large-bodied, high-trophic level, rare
    • Habitat specialists (if habitat included)
    • Species requiring multiple habitat types
  • Shape Reduced edge/area ratio, edge effects
  • Disturbance regime: maintenance of disturbance-generated patch heterogeneity
  • Includes whole functional units
  • Includes whole environmental gradients
size edge effects

From

Primack 2002

SIZE & EDGE EFFECTS

Edges create core versus edge habitat

Example: many songbirds experience high nest predation near edges in woodlots within sub-urban areas

disturbance regime
DISTURBANCE REGIME
  • Disturbance promotes habitat heterogeneity
    • By resetting successional sequence in parts of the landscape
    • Creating patchiness in the landscape which is determined by the temporal and spatial scale of the disturbance(s)
size disturbance regime
SIZE & DISTURBANCE REGIME
  • Disturbance promotes habitat heterogeneity
    • mosaic of patches at different successional stages
  • Habitat heterogeneity:
    • supports species requiring multiple habitat types
    • Supports early successional species (e.g. Heath fritillary butterfly = “Woodman’s follower”)
  • Size of reserve  ideally as big as or bigger than scale of likely disturbances
slide35

Functionally inter-dependent ecosystems:e.g. “a complex, dynamic patchwork of mangroves, sea grass bed and reefs” (Moberg & Ronnback 2003)

SIZE & FUNCTIONAL UNITS

slide36

Reserve design features for persistence

SIZE: Bigger is better!

Edge to area ratio

Disturbance regime

Shape

Environmental gradients

Functional units

Corridors

Matrix habitat

CONNECTIVITY

connectivity
CONNECTIVITY
  • Isolation is a key factor causing loss of species from reserves
    • Preventing gene flow, maintenance of genetic diversity
    • Reducing recolonization following extinction (rescue effect)
    • Preventing access between summer/winter grounds for migratory species
    • Preventing access to multiple habitat types needed for different life stages
    • Preventing response to global warming
connectivity multi scale responses
CONNECTIVITY: Multi-scale responses
  • RESPONSE
  • Create corridors between reserves
  • Manage the matrix around reserves

PROBLEM of FRAGMENTATION

  • Preventing gene flow, maintenance of genetic diversity
  • Reducing recolonization following extinction (rescue effect)
  • Preventing access between summer/winter grounds for migratory species
  • Preventing access to multiple habitat types needed for different life stages
  • Preventing response to global warming
wildlife overpass
Wildlife overpass

Transportation Equity Act for the 21st Century provides funding

http://www.fhwa.dot.gov/environment/wildlifecrossings/overview.htm

managing the matrix
Managing the Matrix

Making matrix “friendly” to wildlife

-- Reserve zonation: core, buffer, transition

-- Wildlife friendly farming/Restoration

Noss and Cooperrider 1994,modified from Harris 1984

connectivity multi scale responses41
CONNECTIVITY: Multi-scale responses
  • RESPONSE
  • Create corridors between reserves
  • Manage the matrix around reserves
  • Protect migratory routes/stop-overs

PROBLEM of FRAGMENTATION

  • Preventing gene flow, maintenance of genetic diversity
  • Reducing recolonization following extinction (rescue effect)
  • Preventing access between summer/winter grounds for migratory species
  • Preventing access to multiple habitat types needed for different life stages
  • Preventing response to global warming
stop over sites along songbird migration routes
Stop-over sites along songbird migration routes
  • Neotropical birds
  • Use radar to detect nocturnal bird movement
    • Timed to get departure events from stopover points (20-40 min after sunset)
    • Signal characteristics

Breeding

wintering

http://www.njaudubon.org/Education/Oases/RadImages.html

connectivity multi scale responses43
CONNECTIVITY: Multi-scale responses
  • RESPONSE
  • Create corridors between reserves
  • Manage the matrix around reserves
  • Protect migratory routes/stop-overs
  • Include whole functional units, disturbance regimes, environmental gradients within reserves or reserve networks
  • Include elevational or latitudinal gradients within reserves

PROBLEM of FRAGMENTATION

  • Preventing gene flow, maintenance of genetic diversity
  • Reducing recolonization following extinction (rescue effect)
  • Preventing access between summer/winter grounds for migratory species
  • Preventing access to multiple habitat types needed for different life stages
  • Preventing response to global warming
slide44

Designing Masoala National Park, Madagascar

  • Habitat heterogeneity – connectedness between habitats, marine and terrestrial
  • Species response to climate change: Include elevational gradients within reserve
  • Masoala, Madagascar
new reserve design methods
New Reserve Design Methods
  • Represent species or habitats efficiently
  • Minimize edge effects, maximize clustering
  • Maximize connectivity

Leslie et al. 2003 Ecol App.

conclusions
Conclusions
  • Biodiversity has great value, both intrinsically, and also because human life depends on it
  • But, it is under threat, from habitat loss and degradation, invasive species, climate change, pollution and over-exploitation
  • Conservation biologists have many tools to protect biological diversity, from genetic to ecosystem levels.
conclusions48
Conclusions
  • Protected areas are an important tool for biodiversity conservation.
  • The design of protected areas and reserve networks should foster representation of biodiversity and its persistence.
    • Reserves need to be sited efficiently to represent biodiversity.
    • Size, shape and connectivity of reserves and relationship with the surrounding landscape matrix are essential considerations for biodiversity persistence.
ad