reserves maintain high diversity and abundance attract human populations why?
Post on 20-Dec-2015
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Reserves
• Maintain high diversity and abundance
• Attract human populations• Why?
Bushmeat
• In Africa, forest referred to as “the bush”• Meat derived from wildlife = bushmeat• Subsistence, trading: multi-billion $/yr in
Africa– ↑ human population, poverty, food insecurity– Private extractive industries facilitate access– Low government capacity for enforcement
• Studies show majority is unsustainable, threatens conservation goals
Project for Ecosystem Management of the Peripheral Zone of the Nouabalé-
Ndoki National Park (PROGEPP)• Government of Congo – WCS Congo –
Private timber company – Communities• No snare hunting• No hunting of legally protected species• No bushmeat export
Wildlife Trade• Trade and exchange of wildlife and wildlife
products made from them• Not all sustainable: leads to quick decline
of many species• Since 1970, 90% of world’s rhinos gone
– Horns for medicinal purposes or dagger handles
• 12,000 African elephants killed annually for domestic markets
Annual World Trade in Selected Wildlife & Plants
Product At leastPrimates (live) 40,000Birds (live) 3,000,000Ornamental fish 350,000,000Furs 40,000,000Reptile skins 20,000,000Reptiles (live) 100,000,000Coral (raw) 1,000 tonsCacti 10,000,000Orchids 2,000,000
(Henley 1995)
Convention on International Trade in Endangered Species
(CITES)• Aim: to ensure international
trade of species does not threaten their survival
• 1975 – IUCN• Voluntary• Listed species decided upon by
member countries– Spp threatened with extinction
• Spp may be threatened through trade– Spp not globally threatened but
member country asked for help in protection
Why are Some Species Rare?
• Body Size • Trophic position• Geographic distribution
– islands– endemics
• Degree of ecological specialization– niche width
• Reproductive rate• Recentcy speciation
Why are Rare Species Prone to Extinction?
• Demographic Stochasticity– By chance alone population fluctuates in
growth rate and hence change in size from one year to the next
– When population is small, extinction can occur with relatively high probability even if chances of survival and successful reproduction are high
Why are Rare Species Prone to Extinction?
• Environmental Stochasticity– random series of environmental changes– a couple of bad years in a row can be
especially devastating to rare populations
• El Niño and Alala– Poor reproduction, even in captivity– Compounding effect of predators (Io)
» specializing on crows more?
Why are Rare Species Prone to Extinction?
• Genetic Problems– Difficulty Finding Mates– Genetic Drift – chance alterations in
small populations: bottlenecks and founder effects
• Inbreeding Depression– Close relatives breed, heterozygosity goes down
because they share many alleles, semilethal recessives are expressed more frequently
– Random Changes in Phenotype– Decreased Genetic Variance
What is the historical pattern of extinction?
• Five major mass extinctions through geologic time– Late Permian--formation of Pangea, loss of shallows,
many marine organism extinctions (Schopf 1974)
Loss ofDinosMostly
Marine
Shallows
(Myers 1997)
Causes of Historic Extinctions are Varied
• Meteors• Continental Drift• Humans
– Pattern of extinctions during last 30,000 years (late Pleistocene) closely matches pattern of human colonization
Human Occupation of Earth
(Diamond 1998--Guns, Germs, and Steel)
So, Extinction is Natural, but Current Episode is Unusual
• Estimated to be 10 - 50 million species on earth– This present extinction rate is 10,000x
greater than background rate through geologic time (Nott et al. 1995)
How Many Extinctions Have Been Documented in last 400 years?
Total of 611 species completely extinct (30 more extinct in the wild but survive in
captivity)• Mammals 86 (3)• Birds 104 (4)• Reptiles 20 (1)• Amphibians 5 (0)• Fishes 81 (11)• Molluscs 230 (9)• Crustaceans 9 (1)• Insects 72 (1)• Other inverts 4 (0)
(Pimm et al. 1995; Chapin et al 2000)
Current extinction risk
Distribution of Imperiled Species by Ecoregion
Number ofSpecies
Number ofEndemic Imperiled Species
1-20
21-50
51-150
> 150
1-10
11-50
51-150
> 100
6-5Source: Precious Heritage (2000) © TNC, NatureServe
Vulnerable Orders
• Loss of all representatives of an Order would be extreme pruning of tree of life
• Mammal orders at risk– e.g. elephant, monotremes
• Bird orders at risk – e.g. cranes
• Reptiles– e.g. tuatara
Endangered Species Preservation Act (1966)
• 1st attempt to address species endangerment comprehensively
• Determined the wildlife facing extinction in the U.S. and sponsored research on those species
• “Taking” of endangered species prohibited only on NWR• Take = harass, harm, pursue, hunt, shoot, wound,
kill, trap, capture, or collect, or to attempt to engage in any such conduct
• Relatively weak legislation but good foundation
Endangered Species ConservationFederal Level
Endangered Species Conservation Act (1969)
•Expanded 1966 Act: includes all vertebrates and some invertebrates in danger of “worldwide extinction”
•Prohibits importation or sale of endangered species or their products
•Addition of foreign species to the U.S. list•Leads to the formation of the Convention on
International Trade in Endangered Species (CITES, 1973)
Endangered Species ConservationFederal Level
Endangered Species Act (ESA, 1973)• Extends protection to plants• Stresses maintaining integrity of the ecosystems • Goal = “recover” listed species• Prohibits federal agencies from authorizing,
funding, or carrying out any action that would jeopardize a listed species or destroy or modify its "critical habitat"
• Distinctions made between threatened and endangered
• Day to day implementation falls to USFWS and NOAA
Endangered Species ConservationFederal Level
Endangered Species Act
• Endangered species: an animal or plant species in danger of extinction throughout all or a significant portion of its range
• Threatened species: an animal or plant species likely to become endangered within the foreseeable future throughout all or a significant portion of its range
Steps in Classification and Conservation•Petition Process•Classification•Recovery Team•Recovery Plan•Critical habitat•Implement Recovery Plan•Monitor populations•Re-classify or de-list
Endangered Species Act
So, What Do We Do?
Use Scientific Method to Identify Threat
Determine Spatial Extent of Protection
REMOVE THREAT
Release Probeto Test if Threat
is Removed
Captive Breeding
MonitorRecovery
Restock
Managein situ
Set up Reserves
?
Removing threat of conservation reliant species
Modify habitat• Control of invasives• Use of prescribed fire to maintain suitable
habitat• Restrict grazing or public accessModify interactions• Predator control• Limited translocations to maintain genetic
diversity
Endangered SpeciesManagement
PoliticalConsiderations
LandUse
LegalConstraints
CompetitionWith Other Wildlifeand PeopleBiological
Knowledge
LimitedHabitat
LimitedBreeding Population
Constraints on Endangered Species
Management