CHAPTER 14 : Ecology & Biodiversity

What is Conservation Biology? Conservation Biology = to preserve and conserve species, communities and ecosystems Studies the causes of decline in species richness and methods to prevent declines

Why Conservation Biology? to prevent excessive rate of extinction to update the status of ecosystems and their services measures to be taken to sustain ecosystem functions

Disruption of energy flow through food chains and webs Disruption of biogeochemical cycles Lower species diversity Habitat loss or degradation Less complex food webs Lower stability Ecosystem collapse © 2004 Brooks/Cole – Thomson Learning  Physiological changes  Psychological changes  Behavior changes  Fewer or no offspring  Genetic defects  Birth defects  Cancers  Death Organism Level  Change in population size  Change in age structure (old, young, and weak may die)  Survival of strains genetically resistant to stress  Loss of genetic diversity and adaptability  Extinction Population Level Community or Ecosystem Level  Disruption of energy flow and biogeochemical cycles  Lower sp diversity  Habitat loss & degradation  Ecosystem collapse  Less complex food webs  Lower stability Environmental Stress Environmental Stresses defined at 3 levels : organism, population and Ecosystem

the variety of species in the ecosystems Definition of Biodiversity

Levels of Biodiversity

Three levels of biodiversity Genetic diversity in a vole population Species diversity in a coastal redwood ecosystem Community and ecosystem diversity across the landscape of an entire region

Genetic Diversity Variation between distinct populations of the same species or varieties Brought about by genetic recombination, gene and chromosomal mutation The gene pool is shaped by Natural Selection – –variation – –reproductive fitness and – –mode of inheritance – –competition

Species Diversity The variety of species in an ecosystem or the biosphere – –Species diversity – variety (diversity) of species or species richness Threatened species Endangered species

Classification of organisms Endangered - - individuals are few and could become extinct over all or most of its range, - moves from endangered to critically endangered Threatened - - still abundant in natural range but declining and is likely to become endangered

Silversword plant at Hawaii, an endangered species Credit: © Michele Burgess/Visuals Unlimited

Key Deer, Florida, an endangered species. Credit: © Arthur Morris/Visuals Unlimited

Museum specimen of the Passenger pigeon, North America that became extinct in Credit: © Ken Lucas/Visuals Unlimited

Illegal Cambodian market with baby Macaques, adult Porcupine, and Crocodile skulls. Credit: © Robert Fournier/Visuals Unlimited

Tiger bones in sesame oil for illegal sale in Myanmar market, folk medicine. Credit: © Robert Fournier/Visuals Unlimited

Snake skin, Sambar skull, and Elephant penis hanging in illegal market in Myanmar. Credit: © Robert Fournier/Visuals Unlimited

Ecosystem Diversity Variety of places where life exists, where there is exchange of energy and nutrients Each habitat is a home for multitude of species, and species are dependent on these habitats – food, mating, protection, etc. When habitats are destroyed, species niche are destroyed, and species follow suit

Cultural Diversity Natural environment provides aesthetic, spiritual and educational needs for tribal people in Africa, Asia, Oceania and Americas This relationship has allowed sustainable use of resources and has allowed for humans and other species to prosper together

Biodiversity Crisis Extinction is a natural phenomenon The current rate of extinction due to ecosystem degradation by a single species – Homo sapien, underlie the biodiversity crisis

Major Threats to Biodiversity Habitat Destruction and Fragmentation Introduction of Non Native Species Over-exploitation/Overuse of Natural Resources Disruption of Food Chains Climate Change Pollution Predator & Pest Control Commercial Hunting & Poaching Sale of Exotic Pets and Decorative Plants

Species Endemism and Hot Spots Endemic – a species found naturally in only one geographic area and no where else E.g – –Komodo dragon – Varanus komodoensis – only found on some islands in Indonesia – –The orang utan – Pongo pygmaeus – only found in Borneo and Sumatra Hotspots – area having concentration of endemic species – in SEA – Peninsular Malaysia, Indonesia, Borneo, Philippines

Earth’s terrestrial biodiversity hot spots Terrestrial biodiversity hot spots Equator

How has human activity affected Global Biodiversity? Figure showing Major connections between Human Activity and earths Biodiversity

Human Population Size and resource use Human Activities Agriculture, industry, economic production and consumption, recreation Indirect Effects Direct Effects Degradation and destruction of natural ecosystems Alteration of natural chemical cycles and energy flows Changes in number and distribution of species Pollution of air, water, and soil Climate change Loss of biodiversity Anthropogenic activities affecting Biodiversity

The Species Approach The Ecosystem Approach Goal Protect species from premature extinction Strategies Identify endangered species Protect their critical habitats Tactics Legally protect endangered species Manage habitat Propagate endangered species in captivity e.g panda Reintroduce species into suitable habitats e. bettong sp. Goal Protect populations of species in their natural habitats Strategy Preserve sufficient areas of habitats in different biomes and aquatic systems Tactics Protect habitat areas through private purchase or government action (PA) Eliminate or reduce populations of alien species from PA Manage PA to sustain native species Restore degraded ecosystems Goals strategies and tactics to reduce biodiversity losses

Three types of Species Extinction Local extinction – not found in local area but elsewhere still found Ecological extinction –few members are left & no longer play ecological roles Biological extinction – when species no longer found anywhere on earth

Some Endangered and Threatened species

(a) Philippine eagle (b) Chinese river dolphin (c) Javan rhinoceros

Figure 22-7 (1) Page 564 Florida manatee Northern spotted owl (threatened) Gray wolfFlorida panther Bannerman's turaco (Africa) Devil's hole pupfish Snow leopard (Central Asia) Black-footed ferret Symphonia (Madagascar) Utah prairie dog (threatened) Ghost bat (Australia) California condor Black lace cactus Black rhinoceros (Africa) Oahu tree snail

Figure 22-7 (2) Page 565 Grizzly bear (threatened) Arabian oryx (Middle East) White top pitcher plant Kirtland's warbler African elephant (Africa) Mojave desert tortoise (threatened) Swallowtail butterfly Humpback chub Golden lion tamarin (Brazil) Siberian tiger (Siberia)

Figure 22-7 (3) Page 565 West Virginia spring salamander Giant panda (China) Knowlton cactus Mountain gorilla (Africa) Swamp pink Pine barrens tree frog (male) Hawksbill sea turtle El Segundo blue butterfly Whooping crane Blue whale

Characteristics of species that are prone to ecological and biological extinction (*) (*)Ecological extinction –few members are left & no longer play ecological roles (*) Ecological extinction –few members are left & no longer play ecological roles (*)Biological extinction – when species no longer found anywhere on earth (*) Biological extinction – when species no longer found anywhere on earth

CharacteristicExamples Low reproductive rate (K-strategist) Specialized niche Narrow distribution Feeds at high trophic level Fixed migratory patterns Rare Commercially valuable Large territories Blue whale, giant panda, rhinoceros Blue whale, giant panda, Everglades kite Many island species, elephant seal, desert pupfish Bengal tiger, bald eagle, grizzly bear Blue whale, whooping crane, sea turtles Many island species, African violet, some orchids Snow leopard, tiger, elephant, rhinoceros, rare plants and birds California condor, grizzly bear, Florida panther Everglades kite California condor African violet

How does a biologist know if a particular species is vulnerable to extinction? 1. Observing changes in an organisms population size and habitat availability 2. Species whose populations are shrinking rapidly 3. Species whose habitats are being destroyed 4. Species that are endemic to small area and rare

Species-Area Curves 90% deforestation/loss of habitat causes extinction of 50% of species Destruction of last 10% causes extinction of all species especially if the species cannot move out of the area

How do biologist estimate extinction rates? 1. PVA – Population Viability Analysis 2. MVP – Minimum Viable Population 3. MDA – Minimum Dynamic Area

Population Viable Analysis (PVA) to predict if population will persist based on: i.Current & predicted habitat condition and resource needs ii.Genetic variability iii.Interactions with other species iv.Reproductive rates and population dynamic

Minimum Viable Population (MVP) Minimum number of individuals necessary to ensure survival of a population

Minimum Dynamic Area (MDA) Minimum area of suitable habitat needed to maintain the MVP

The Value of Biodiversity

Why should we care about biodiversity – what’s so bad about losing it – what’s it value? 1. Direct Economic Value (consumable) - nature product that are consumed directly – consumptive use value that do not pass through markets 2. Indirect Economic Value (ecological services) 3. (Option value) Natures products that are commercially harvested – productive use value – biological resources 4. Ethical & Aesthetic Value

Why Conserve Biodiversity? Why Conserve Biodiversity?

Necessity – genetic codes are linked to medicines, food production, jobs and survival Important to Economy Essential for Food Security

Safeguards Human Health Recreation & Tourism Global Concern - Losses to biodiversity can threaten national security – conflicts over water, land, global warming Species Extinction Aesthetic Beauty

Underlying and direct causes of depletion and premature extinction of wild species Two biggest causes 1.Habitat loss, fragmentation & degradation 2.Introduction of nonnative species

Animal Habitat Loss

Figure (4) Page 573 Asian or Indian Elephant Former range Range today (34,000–54,000 left)

Characteristics of Successful Invader Species High reproductive rate, short generation time (r-selected species) Pioneer species Long lived High dispersal rate Release growth- inhibiting chemicals into soil Generalists High genetic variability Characteristics of Ecosystems Vulnerable to Invader Species Similar climate to habitat of invader Absence of predators on invading species Early successional species Low diversity of native species Absence of fire Disturbed by human activities

Poaching & Hunting

Protecting Wild Species Wildlife Refuges, Protected Areas Gene Banks, Botanical Gardens, Farms Zoos, Aquariums

An artificial corridor