Transcript Impacts of Catastrophes

Legislative Response to Endangerment
 Lacey Act (1900; amended 1981)
– Game birds and other birds, possession of protected species
 Endangered Species Preservation Act of
1966
– Habitat acquisition
 Endangered Species Conservation Act of
1969
– Inverts, trade,
– Started process that led to CITES
 Endangered Species Act of 1973
– amended 1978, 1982, 1988
CITES
 Convention on International Trade in
Endangered Species of Wild Fauna and
Flora
– Signed 3 March 1973, Implemented 1975,
Amended 1979
– Requires permit for import or export of species
listed
• includes body parts like ivory, leather, shrunken
heads, etc
ESA of 1973
 Basic Intent and Purpose
– “to provide a means whereby the ecosystems upon which
endangered species and threatened species depend may be
conserved, to provide a program for the conservation of such
endangered species and threatened species, and to take such steps
as may be appropriate to achieve the purposes of the treaties and
conventions set forth in subsection (a) of this section”
– “a law that plays in when local planning and zoning, state fish and
wildlife efforts, the Clean Water Act, and Clean Air Act haven’t
worked. It is the emergency room of conservation policy” (M.
Beattie 1995)
Classifying Endangerment
 Listing species is first step toward
conservation
 During listing they are classified as
“Endangered” or “Threatened”
– endangered- “any species which is in danger of
extinction throughout all or a significant portion of its
range”
– threatened- “any species which is likely to become an
endangered species within the foreseeable future
throughout all or a significant portion of its range”
What are T&E Functionally?
 Wilcove et al. (1993) reviewed
characteristics of listed species
– Endangered animals (median values)
• 515 individuals, 1-5 populations
– Endangered plants (medians)
• 99 individuals, 3 populations
– Threatened animals
• 4161 individuals, 1-5 populations
– Threatened plants
• 2499 individuals, 9 populations
IUCN Categories
 Much more biologically based (Mace and
Lande 1991 and updates)
– Extinct
– Extinct in the wild
– Threatened
• Critically Endangered
• Endangered
• Vulnerable
– Lower Risk
• Near Threatened
• Least Concern
Flow Chart of Categories
(Gärdenfors 2001)
Threatened IUCN Categories
 Critically Endangered “extreme risk of
extinction in the wild in the immediate future”
 Endangered “high risk of extinction in the
wild in the near future”
 Vulnerable “high risk of extinction in the
wild in the medium-term future”
(Gärdenfors 2001)
Applying IUCN at the Regional
Scale
(Gärdenfors 2001)
ESA vs IUCN categories
 Wilcove et al.’s analysis suggests that listed
species in US under ESA are in two most
critical classes of IUCN categorization
– low number of indivduals (<5000) and few (<9)
populations
– emphasizes that the ESA is REACTIVE not
proactive and shows why many species do not
recover after listing--they’re too far gone
already
But, What Do We Mean by “Species”?
 ESA and CITES define species as “any subspecies
of fish or wildlife or plants, and any distinct
population segment of any species of vertebrate
fish or wildlife which interbreeds when mature”
– plant populations do not get special
consideration
– NMFS often lists fish stocks (local noninterbreeding populations)
• concept of Evolutionary Significant Unit (requires
reproductive isolation)
What is Actually Listed?
 Wilcove et al.’s Analysis suggested that most
listed species were full species
– only 20% of listed species were subspecies or
populations, but this varied by taxonomic group
• birds---80% of listed “species” were subspecies or
populations
• mammals--70% of listed “species” were subspecies
or populations
• Mollusks--5%of listed “species” were subspecies or
populations
• Plants--14% of listed “species” were subspecies or
populations
Proactive or Reactive?
 Seems the ESA is proactive for birds and
mammals, but reactive for plants and inverts
based on the type of unit that is listed.
Biological vs. Evolutionary
Species Concepts
 ESA uses a biological species concept
because it emphasizes that groups to be
listed are reproductively isolated from other
such groups
 But, if the goal is to preserve biodiversity,
then what we really want to preserve is
unique genetic material, thus the
evolutionary species concept may be more
appropriate
Biological vs. Evolutionary
Species Concepts
 Evolutionary species are those lineages that
maintain their “own evolutionary tendencies and
historical fates” (Wiley 1981)
 The National Research Council (NRC) review of
the ESA discusses the EU and suggests it may be
an especially valuable way to view species for
listing
– Evolutionary Unit-- “group of organisms that
represents a segment of biological diversity that
shares evolutionary lineage and contains the
potential for a unique evolutionary future”
Defining EUs
 The NRC suggests that EUs are “segments
of biodiversity that contain a potential for a
unique evolutionary future”
– Define by distinctiveness from other units
• morphology, genetics, reproductive isolation,
ecological distinctiveness, behavior, and physiology
– Hybrids can be included as EUs if they are not
genetically dependent on parental species
Evolutionary Significant Units
•Others have defines EUs, or more generally, ESUs
•Reviewed in Crandall et al. 2000
•Ryder 1986: populations that actually represent significant
adaptive variation based on concordance between sets of
data derived by different techniques
•Waples 1991: populations that are reproductively separate
from other populations and have unique or different
adaptations
•Moritz 1994: populations that are reciprocally
monophyletic for mtDNA alleles and show significant
divergence of allele frequences at nuclear loci
Ecological and Genetic Exchangeability
(Crandall et al. 2000)
•Ecological exchangeability: the factors that define the
fundamental niche and the limits of spread of new genetic
variants through genetic drift and natural selection
•rejected with evidence for population differentiation
owing to genetic drift or natural selection
•Differences in life histories, morphology, habitat,
allozymes under selection (preferably heritable ones)
•Genetic exchangeability: the factors that define the limits and
spread of new genetic variants through gene flow
•Rejected when there is evidence of restricted gene flow
between populations
•Differences in microsatellites, nucleotide sequences,
(mtDNA, cpDNA, nDNA) and allozymes
Assessing
Ecological and
Genetic
Exchangeability
(Crandall et al. 2000)
References
 Crandall, KA, Bininda-Emonds, ORP, Mace, GM, and RK Wayne. 2000. Considering
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evolutionary processes in conservation biology. Trends in Ecology and Evolution.
15:290-295.
Gardenfors, U. 2001. Classifying threatened species at national versus global levels.
Trends in Ecology and Evolution. 16:511-516.
National Research Council. 1995. Science and the endangered species act. National
Academy Press. Washington, DC.
Moritz, C. 1994. Defining “evolutionary significant units” for conservation. Trends in
Ecology and Evolution. 9:373-375.
Ryder, OA. 1986. Species conservation and systmatics: the dilemma of subspecies.
Trends in Ecology and Evolution. 1:9-10.
Waples, RA. 1991. Pacific salmon, Oncorhynchus spp., and the definition of “species”
under the endangered species act. Marine Fisheries Review. 53:11-22.
Wiley, E. 1981. Phylogenetics: the theory and practice of phylogenetic systematics. New
York. John Wiley & Sons
Wilcove, D.S, M. McMillan, and K. C. Winston. 1993. What exactly is an endangered
species? An analysis of the U.S. Endangered Species List: 1985-1991. Conservation
Biology 7:87-93.