Chapter 1: What is conservation biology?

Biodiversity = includes all species, genetic variation, and biological communities and their ecosystem- level interactions

Conservation biology = integrated multidisciplinary scientific field that has developed in response to challenge of preserving species and ecosystems. 3 goals

1. To document full range of biodiversity2. To investigate human impact on species, genetic variation, and ecosystems3. To develop practical approaches to prevent extinction of species, maintain genetic diversity

within species, and protect and restore biological communities and associated ecosystem functions

Conservation biology is a normative discipline: embraces certain values and attempts to apply scientific methods to achieving those values

Conservation biology merges applied and theoretical biology and incorporates ideas and expertise from a broad range of fields outside the natural sciences toward the goal of preserving biodiversity

Conservation biology closely associated with environmentalism: widespread movement with political and educational activism with goal of protecting natural environment from destruction and pollution

-. Conservation biology is based in biological research while environmentalism is not

Conservation biology represents synthesis of many basic sciences, which provide principle and new approaches for applied fields of resource management. Experience gained in field influence direction of basic science

-. Basic science new ideas and approaches resource management field experience and research needs basic science

Ethical principles of conservation biology:

-. Diversity of species and ecosystems should be preserved

-. Biophilia = love of biodiversity

-. Diverse environments = resources = help human survival

-. Economic value of biodiversity

-. Untimely extinction of populations and species should be prevented

-. Rate of extinction increased by humans

-. Ecological complexity should be maintained

-. Natural environments are important (think pollination)

-. Evolution should continue

-. Species in captivity are cut off from natural evolutionary processes

-. Biodiversity has intrinsic value

Origins of conservation biology can be traced to religious and philosophical beliefs concerning relationship between human societies and natural world

-. People seen as physically and spiritually connected to plants and animals in surrounding environment

-. Natural areas used for intense spiritual experiences

-. “For the Kuna culture, the land is our mother and all living things that we live on are her brothers in such a manner that we must take care of her and live in a harmonious manner with her, because the extinction of one things is also the end of another

European mindset = God created nature for humans’ use and benefit

-. Justifies all land use and implies leaving land unused is to foolishly misuse God’s gift

-. Anthropocentric view of nature led to exploitation and degradation of vast resources colonized by European countries

-. Need of non-Europeans native peoples disregarded

-. Scientific officers noticed devastation in colonialism in 18th and 19th centuries

-. Many themes of contemporary conservation biology were established in European scientific writings

-. Firearms led to extinction of species by hunting

-. Creation of conservation organizations

American efforts originated by philosophers Ralph Waldo Emerson & Henry David Thoreau

-. Emerson = Transcendentalism = achieve spiritual enlightenment through nature

-. Thoreau = opponent of materialistic society (Walden)

John Muir = American wilderness advocate

-.Preservationist ethic = natural areas such as forest groves, mountaintops and waterfall have spiritual values that are generally superior to tangible material gain obtained by exploitation

-. Argued nature has intrinsic value argued that destroying nature would be destroying God’s work

Grifford Pinchot = first head of U.S. Forest service

-. Resource conservation ethic = proper use of natural resources according to resource conservation ethic is whatever will further “greatest good of greatest number of people for longest time

-. Resources should be fairly distributed and used efficiently

-. Sustainable development = development best meets present and future human needs without damaging environment and biodiversity

Aldo Leopold = Land ethic = humans use policy in which human use of natural resources was compatible with or enhanced biodiversity

-. Ecosystem management = combines Leopold and Pinchot ideas = places highest management priority on cooperation among businesses, conservations organization, government agencies, private citizens and other interested parties to provide for human needs and to maintain the health of wild species and ecosystems

Rachel Carson = Silent Spring = role of pesticides and DDT in loss of bird populations, led to ban of DDT and regulation of toxic chemicals

Conservation biology is a crisis discipline

There are positives in conservation biology: since inception in 1985 the field has continued to grow and conservation activities have continued to expand around the world with new marine protected areas being a notable success

Chapter 2: What is Biodiversity?

Biodiversity means complete range of species and biological communities and genetic variation in species and all ecosystem processes

1. Species diversity: reflects entire range of evolutionary and ecological adaptations of species to particular environment

2. Genetic diversity: necessary for species to maintain reproductive vitality, resistance to disease and ability to adapt in changing conditions

3. Ecosystem diversity: results from collective response of species to different environmental conditions

What is a species?

1. Morphological definition: group of individuals that is physiologically or biochemically distinct from other groups in some important characteristic

2. Biological definition: group of individuals that can potentially breed among themselves in the wild and that do not breed with individuals of other groups

3. Evolutionary definition: group of individuals that share unique similarities of DNA and hence evolutionary past

Taxonomists = biologists who specialize in identification of unknown specimens and classification of species

-. Taxonomists have only escribed about 1/3 of species

-. Kingdom, phylum, class, order, family, genus, species

-. Binomial nomenclature: Carlolus Linnaeus

Morphospecies = one or more individuals that look different from other individuals and might represent a difference species

DNA barcoding = system that will identify the species of a living organism based on DNA from any tissue sample

Cryptic biodiversity = widespread existence of undescribed species that have been wrongly classified and grouped with a similar-appearing species

Hybrids = intermediate forms that may blur distinction between species (when individuals of related but distinct species mate)

Speciation = process of new species formation

-. Theory of evolution: Charles Darwin and Alfred Russel Wallace

Phyletic evolution = gradual transformation of one species into another

Adaptive radiation = process of local adaptation and subsequent speciation

Polyploids = unequal division of chromosome sets during reproduction results in offspring with extra sets of chromosomes

-. Could lead to new species arise in one generation

-. Rate of extinction 100-1000x faster than rate of speciation

Species richness = number of difference species in a place

Alpha diversity = number of species in a certain community or designated area

Gamma diversity = number of species in a large region or continent

Beta diversity = link alpha and gamma, represent rate of change of species composition along an environmental or geographical gradient

-. I.e if each lake in a region contained different fish species, the beta diversity would be high

-. Gamma/Alpha

Population = group of individuals that mate with one another and produce offspring

Genetic variation arises because of different forms of genes = units of chromosomes that code for specific proteins

Alleles = different forms of a gene

Differences in genes arise through mutations= changes that occur in DNA that constitutes an individual’s chromosomes

Recombination = exchanging of genes between chromosomes in sexual reproduction that created genetically unique offspring

Gene pool = total array of genes and alleles in a population

Genotype = particular combination of alleles

Phenotype = morphological, physiological, anatomical, biochemical characteristics of an individual resulting from expression of genotype in a particular environment

Gene frequencies = frequency of genes in a population

Natural selection = individuals with certain alleles better suited for environment will survive and reproduce (to impact gene frequency)

Polymorphic genes = have more than one allele

Heterozygous = receive different allele of gene from each parent

Homozygous = same allele of gene from each parent

Heterozygous individuals have greater fitness (growth, survival, reproduction than homozygous

Hybrid vigor/heterosis = phenomenon of increased fitness in heterozygous individuals

Gene flow = genetic transfer from one population of a species to another that impacts gene frequency

Artificial selection = preservation of organisms forms well suited to human needs

Ecosystem = biological community with physical and chemical environment

Biological community = species that occupy a particular locality and interactions between those species

Biota = a regions flora and fauna (animal and plant life)

Limiting resource = food, temp, water, or other resource which may limit population size and distribution

Succession = gradual process of change over time in species composition, community structure, soil chem, and microclimate characteristics that occurs following natural and human caused disturbances in an environment

Composition of ecosystem is often affected by competition and predation

Carrying capacity = number of individuals an ecosystem can support based on resources

-. Predators keep number of prey below amount of resources available

Ecologically functional = when a population of a species is sufficiently large to have an impact on the other species in a an ecosystem

Mutualistic relationship = two species benefit each other

Symbiotic relationship = two species in a close long-term association

Abiotic environment Primary producers (photosynthetic species) primary consumers (herbivores) secondary consumers (carnivores/predators) decomposers (detritvores)

Disease causing organisms are major threat to many rare species

Biomass = living weight = primary producers bc less energy is transferred to each successive trophic level

Food chain = specific feeding relationships

Food wed = species linked together through complex feeding relationships

Guild = species at same trophic level that use approximately same environmental purposes

Keystone species = particular species or species in a guild that may determine ability of large numbers of other species to persist in the community (often top predators)

Trophic cascade = dramatic change in vegetation and great loss in biodiversity caused by elimination of even small number of individual predators

Ecosystem engineers = species that extensively modify physical environment through activities

Extinction cascade = series of linked extinction events caused by losing keystone species

Keystone resources = physical or structural resources that occupy small area yet crucial to many species

-. Like rotting wood, hollow tree trunks, mineral pools

Ecosystem integrity = condition in which an ecosystem is complete in terms of species composition, structure and function

Healthy ecosystem = ecosystem processing normally with or without human presence

Stable ecosystem = ecosystem able to remain stable

-. Resistance = ability to maintain same state even with ongoing disturbance

-. Resilience = property of being able to return to an original state quickly after disturbance has occurred

Chapter 3: Where is the World’s Biodiversity Found?

Most species rich environments are: tropical forests, coral reefs, deep sea, large tropical lakes and river systems, and regions with Mediterranean climates

Endemic species = species that are found in a particular location and nowhere else

Species richness tends to increase with decreasing elevation, increasing solar radiation, increasing precipitation in terrestrial communities

Species richness can be greater where complex topography and great geological age provide more environmental variation, which allows genetic isolation, local adaptation and speciation to occur

Why are there so many species in the tropics?

1. Tropical regions receive more solar energy over the year and many have abundant rainfall2. Species of tropical communities have had longer periods of stability than species of

temperate communities (bc glaciation)

3. Warm temperatures and high humidity provide favorable conditions for growth and survival of many species

4. Due to predicable environment, species interactions in topics are more intense, leading initially to greater competition among species and later to niche specialization (more parasites and diseases too)

5. Large geographical area of tropics, compared to temperate zone may account for greater rates of speciation and lower rates of extinction

1.5 million species have been described, at least two to three times this number of species remains undescribed

-. Most species will be described by end of 22nd century

Entire biological communities continue to be discovered in extremely remote and inaccessible location (canopy, deep sea)

Best estimate is that there are about 5-10 million species in the world, with half being insects

DNA analyses have suggested thousands of species of bacteria have yet to be described, marine environment contains large numbers of species unknown to science

There is a need for more taxonomists in the world

Chapter 4: Ecological Economics

It is easier to convince governments and corporations to protect biodiversity when there is an economic incentive to do so

Environmental economics/ecological economics = integration of economics, environmental science, ecology, and public policy that include valuations of biodiversity in economic analyses

Externalities = hidden costs, can be positive or negative

Market failure = resources are misallocated, which allows a few individuals or businesses to benefit at the expense of the larger society (allocation of goods and resources is not efficient)

Open-access resources = water, air, soil; commonly overlooked negative externality

Tragedy of the commons = (market failure) value of open-access resource is gradually lost to all of society

-. Think unregulated dumping of industrial sewage into river

-. Negative externalities = degraded drinking water, increase in disease, etc.

Common property = resources owned by society (market failure can occur when there is lack of enforcement of regulations on common property)

Economists evaluate larger development projects using environmental and economic impact assessments: consider present and future effects of projects on environment and economy

Cost-benefit analyses compare values gained against costs of project or resource use

Precautionary principle = may be better not to approve a project that has risk associated with it and to err on the side of doing no harm to the environment rather than to do harm unintentionally

Perverse subsidies = economic activities appearing to be profitable but actually losing money because government subsidize environmental damaging activities with tax breaks, direct payments, cheap fossil fuels, free water and road networks

Discount rates = commonly used by economists to calculate present value of natural resources that will be harvested or used at some point in the future

-. Lower current values will be assigned to resources used in future bc it is better for society to have money now and invest

GDP = gross domestic product

Green accounting, Index of sustainable economic welfare and environmental performance index all used to measure natural resource depletion

Economic value can be assigned on three levels:

1. Marketplace value of resources2. Value provided by unharvested resources in natural state3. Future value of resources

Use value

-. Direct use value: products harvested by people (timber, seafood, medicine)

-.Consumptive use value: goods consumed locally (not in GDP)

-. Bushmeat

-. Replacement cost approach: how much people would have to pay if they had to buy an equivalent product when their local source is no longer available

-. Productive use value: products sold in markets

-. Wood, caffeine, cocaine, ephedrine

-. Indirect use value: benefits provided by biodiversity (recreation, education)

-. Option value determined by prospect for possible future benefits to human race (new medicine, future food sources)

Non-use value

-. Existence value

-. Bequest value: how much people are willing to pay to protect something for their children or future generations

Chapter 5: Indirect Use Value

Ecosystem services = benefits harvested from ecosystem for humankind

Ecosystem services include: provisioning (food, water, fuel), cultural (spiritual, aesthetic), regulating (climate control, soil retention), supporting (primary production, soil formation) essential for human well-being (health, basic material for comfortable life, security from disasters, stable society, freedom of choice, enhancement of science and art)

Ecosystem with reduced species diversity may be less able to adapt to altered conditions with rising CO2 levels, higher temps, and other aspects of global climate change

Social value of carbon = financial impact on society of producing a ton of carbon and then to tax carbon emission and subsidize sequestration based on this value

Wetland ecosystem service whose value is typically not accounted for in the current market system include waste treatment, water purification, and flood control – all of which are essential to healthy human society

Plant communities moderate climate conditions

Species relationships are important (bats provide surprisingly important ecosystem services in from of agricultural pest control, pollination is also important

Species that are particularly sensitive to chemical toxins serve as environmental monitors

Amenity value = monetary value of activities (important for recreational services)

-. Can have major impact on local economies

-. Ecotourism = people visiting places and spending money wholly or in part to experience unusual biological communities

-. 20% of tourism industry

-. Tourists could unwittingly damage ecotourism sites

Educational use of biology has large economic influence

Option value = species potential to provide an economic benefit to human society at some point in the future

Potential economic or human health value of natural resources motivates people and countries to protect biodiversity

Bioprospecting = searching biological communities for new plants, animals, fungi and microorganisms that can be used to fight human disease or provide some economic value

Biopiracy = past and present unauthorized collecting of biological materials for commercial purposes

“Who own the commercial rights to the world’s biodiversity?”

Existence value = amount people are willing to pay to prevent species from going extinct, habitats from being destroyed, and genetic variation from being lost

Bequest value = how much people are willing to pay to protect something of value for their own children and descendants, or for future generations

People, governments and organizations pay a lot of money annually to ensure some species stay alive and some ecosystems remain healthy: birds, whales, sharks, rainforests, lakes

Major structural changes are needed to change how we view ecosystem, even in terms of the economy (minority uses majority of resources, people are dying in poverty)

Chapter 6: Ethical Values

Environmental ethics = articulates value of natural world

Ethical and religious arguments can complement economic and biological arguments for protecting biodiversity – these arguments are readily understood by many people

An argument can be made that people have a responsibility to protect species and other aspects of biodiversity because of their intrinsic value, not just because of human needs

Intrinsic value = value for its own sake

“It is necessary to use nature, but not all use of nature is necessary”

All species and ecosystems are interdependent, and so all parts of nature should be protected – it is in long term survival interest of people to protect all of biodiversity

People have a responsibility to act as stewards of the earth

-. Leaders of world’s religions increasingly prioritize the conservation of natural resources and respect for all life

People have a duty to their neighbors

People have a responsibility to future generations

Respect for human life and human diversity is compatible with a respect for biodiversity

-. Environmental justice and social justice are related since both encourage broad respect for all kinds of life, both human and non-human

-. Win-win scenarios

Preserving biodiversity is in our material self-interest

We should act altruistically towards nature regardless of out material self-interest

Enlightened self interest = preserving biodiversity and developing our knowledge of it will make us better and happier people

-. Maintaining full diversity of life improves opportunities for scientific investigation and religious inspiration

-. Aesthetic and recreation; artistic expression and philosophical insight, historical understanding, protecting life-support system and economy

Affluenza = unsatisfying and unending pursuit of increasing material wealth

Deep ecology = environmental philosophy that advocates placing greater value on protecting biodiversity though changes in personal attitude, lifestyle and even societies

Chapter 7: Extinction

Extinct = no member of the species is found alive anywhere in the world

Extinct in the wild = species remain alive on in captivity

Globally extinct = both extinct and extinct in the wild

Locally extinct/ extirpated = species no longer found in specific area, but still inhabits elsewhere in wild

Regionally extinct = extinct in country or region but still persist in another part of its range

Ecologically extinct = persist at such reduced number that its effects on other species in its community are negligible

Current rate of species loss is unprecedented and irreversible – utmost concern

Five past episodes of mass extinction

Sixth extinction event is caused by humans – not natural disaster

-. Many large mammal species became extinct when people arrived to each of the continents, - almost certainly caused by humans

Extant = still living

Many species (especially insects) thought to be extant may have become extinct, just unreported

Extinction debt = presumed eventual loss of species following habitat destruction and fragmentation

Many species toady are represented only by scattered populations, each consisting of a few individuals – although these isolated populations could persist for years or decades, the ultimate fate of such species is extinction

Current rate of species loss is unprecedented and irreversible. 99% of current extinctions are caused in some way by human activities

Endemic = found in one place and nowhere else

Island species have higher rates of extinction than mainland species. Freshwater species are more vulnerable to extinction than marine species

Island-biogeography model = general rules on distribution of biodiversity, model used to estimate future extinction rates

Species-area relationship = islands with large areas have more species than islands with smaller areas

-. Large islands allow larger number of separate populations, larger sizes of populations increasing likelihood of speciation and decreasing probability of local extinction of newly evolved and recently arrived species

-. S=CA^Z; s=number of species, c,z=constants, a= area of island

-. Extinction rates = rate of immigration of new species (low to high): small near, large near, small far, large far

Island biogeography model can be used to predict how many species will go extinct due to habitat loss. Model can also be used to predict how many species will remain in protected areas of different sizes

-. Has variables: broad geographical range, forests, nonrandom events, degree of habitat frag.

Historical models used to predict how long it will take for species to go extinct

Many species are experiencing loss of populations across range. Such local extinctions results in loss of species richness at local level, with potential implications for ecosystem function and enjoyment of nature

Species rich tropical rain forests are being lost at rate of 1% a year, rate believed to result in destruction of more than 13500 biological populations each day, population loss will eventually result in species extinctions

Chapter 8: Vulnerability to Extinction

Rare species considered especially vulnerable to extinction

Species is rare:

1. Lives in narrow geographic range2. Occupies only one or a few specialized habitats3. Is found only in small populations

Endemic = found in one place and no other place

-. Often found in isolated areas, remote places (mountain tops, old lakes)

Neoendemic = occupy small range because they have only recently evolved from closely related species

Paleoendemic = ancient species whose close relatives have all gone extinct (giant panda)

Identifying characteristics of extinction-prone species allows conservation biologists to anticipate the needs of vulnerable species, even when detailed data are lacking

Species are vulnerable to extinction if:

1. Species has narrow geographical range2. Species only has one or a few populations3. Species has small population size4. Species has declining population size5. Species is hunted or harvested by people

-. Other linked characteristics are: species that need large home ranges, species with large bodies, species that are not effective dispersers, seasonal migrants, species with little genetic variability, species with specialized niche requirements, species that are characteristically found in stable, pristine environments, species that form permanent or temporary aggregations, species that have not had prior contact with people, species that have closely related species that are recently extinct or are threatened with extinction

-. Allele Effect = when population size or density falls and species cannot forage, find mates or defend themselves

IUCN = international union for conservation of nature

Red list criteria: observable reduction in numbers of individuals, total geographical area occupied by species, predicted decline in number of individuals, number of mature individuals currently alive, probability species will go extinct within a certain number of years of generations

CR = extremely high risk of going extinct in wild

EN = very high risk

VU = high risk

NT = close to qualifying for threatened

LC = not considered near threatened or threatened

DD = inadequate info

NE = not yet evaluated

Red list = detailed lists of endangered species by group and by country

Red list index = demonstrates conservation status of certain animal groups has continued to decline since 1988

Living planet index = follows population sizes for 2688 vertebrae species, shown decline of 61% tropical species and average 31% increased for temperate species

Endangered Species Act = ESA, created by Congress to provide a means whereby ecosystems upon which endangered species and threatened species depend may be conserved and to provide a program for the conservation of such species (legal protection)

NatureServe network is similar to IUCN

Chapter 9: Habitat Destruction, Fragmentation, Degradation and Global Climate Change

Humans dominate global ecosystem:

1. Land surface (agriculture and forestry)2. Nitrogen cycle (fossil fuels, nitrogen-fixing crops, nitrogen fertilizers raise nitrogen levels)3. Human use of fossil fuels and deforestation (CO2 levels up)

Major threats to biodiversity are: habitat destruction, habitat fragmentation, pollution, global climate change, overexploitation of resources, invasive exotic species, spread of diseases – all rooted in expanding human population

Globalization = increased interconnectedness of resource and labor markets

Ecological footprint = influence group of people has on both surrounding environment and locations across the globe

I = PAT; I=impact, P= number of people, A = avg income. T = level of technology

The enormous consumption of resources in an increasingly globalized world is not sustainable in long term

Habitat destruction results from expansion of human populations and human activities

Shifting cultivation = subsistence farming, slash and burn agriculture where trees are cut down and burned away, cleared patched are farmed for 2/3 seasons then soil fertility diminishes and areas are abandoned

-. Destroying tropical rain forests

Demands of coffee, chocolate, palm oil, soy beans, timber and beef products in the US, China and other industrialized nations help fuel the destruction of vast expanses of tropical rain forest

Tropical deciduous, grasslands, wetlands and aquatic habitats are also threatened.

Mangroves and coral reefs also being degraded

Desertification = ecosystems in dry climates degraded by humans into man-made deserts

As human population grows, people and domesticated animals move into drylands that cannot support their numbers turning semiarid areas into full-blown deserts

Habitat fragmentation = process where large continuous area is both reduced in area and divided into two or more fragments

Edge effect = edges experience altered set of conditions

Habitat fragments differ from original habitats by:

1. Fragments have greater amount of edge per area2. Center of each habitat frag is closer to edge3. Continuous habitat hosting large population is divided into pieces with smaller populations

Habitat fragmentation: limits dispersal and colonization, restricted access to food and mates

-. Create small subpopulations that are vulnerable to local extinction

Habitat fragmentation increases edge effects: changes in light humidity and wind that may be less favorable to many of original species

Pollution of air, water and soil by chemicals, wastes and by-products of energy production destroys species, habitats and ecosystems in ways that are sometimes difficult to detect

-. Pesticide pollution

-. Biomagnification = DDT became concentrated as it ascends the food chain (Rachel Carson, Silent Spring)

-. Water damage not only damages biodiversity but also harms health of people who use water

-. Eutrophication = nitrogen stimulates plant and algal growth, dominate water, deplete oxygen

-. Acid rain and other types of air pollution are increasing rapidly in Asia as countries there industrialize. Acid rain is particularly harmful to freshwater species

-. Photochemical smog = ozone and secondary chemicals produced by release of hydrocarbons and nitrogen oxides as waste products into the air

Greenhouse gases = CO2, methane, sunlight passes through and warms the earth, slows release of heat from earth

Greenhouse effect = warming effect of earth by its atmospheric gases, act as blanket on earth’s surface, denser blanket = more warmth

Global warming = increased temperature resulting from greenhouse effect

Global climate change = refers to complete set of climate characteristics changing now and will continue to change in the future

IPCC = intergovernmental panel on climate change = study group of leading scientist organized by UN agrees increased levels of greenhouse gases are contributing to global warming

Evidence:

1. Increased temp and incidence of heat waves2. Melting of glaciers and polar ice3. Rising sea levels4. Earlier spring activity5. Shift in species’ ranges6. Population declines

As rainfall patterns change and most regions become warmer many plant and animal populations may not be able to adapt quickly enough to survive and habitat frag may prevent them from migrating to viable regions

Climate change is predicted to cause both rising sea levels and increasing seawater temp with broad implications for marine ecology and coastal areas

Assisted colonization = transplant isolated populations of rare and endangered species to new localities at higher elevations and closer to poles where they can survive

Chapter 10: Overexploitation, Invasive Species, and Disease

Overexploitation threatens ¼ of endangered vertebrates

Today’s vast human population and improved technology have resulted in unsustainable harvest levels of many species and other biological resources

Bushmeat crisis = decline of animal populations caused by intensive hunting of animals

Species can often recover when they are protected from overexploitation

Overharvesting of wildlife has increased to supply global marts, both legal and illegal

Maximum sustainable yield = the greatest amount of a resource that can be harvested each year and replaced through population growth without detriment to the population

-. Ymax=rK/4 where k=largest pop that a given area can support

Commercial fisheries have been overharvested due to pressure for high harvest levels, fluctuating fish populations and illegal harvests. Many noncommercial species are caught and killed accidentally as bycatch during fishing activities

Bycatch = caught incidentally ¼ to ¾ of bycatch released into ocean dies

Certifying timber, seafood, and other products as coming from sustainable management practices may be a way to prevent overharvesting

Invasive species may displace native species though competition for limiting resources, they may prey upon native species to the point of extinction, or they may alter habitat so that natives are no longer able to persist

Anthropocene = altered species distribution part of pattern of extensive human impacts could be entering this era

Exotic species = species that occur outside their natural range because of human activity

Invasive species = new species establish themselves in new home, may spread and increase rapidly at expense of native species

Species introductions have occurred because of:

1. European colonization2. Agriculture, horticulture, aquaculture3. Accidental transport4. Biological control

Many islands have been driven to extinction by invasive species. Freshwater and marine ecosystems may also be altered by invasive species

Genetic swamping = when invasive species hybridize with native species and unique genotypes may be eliminated from populations and taxonomic boundaries may be obscured

When human development changes the environment, invasive species and undesirable native species may thrive. Hybridization between rare native species and invasive species may blur species boundaries

Countries need to prevent introduction of new invasive species, to monitor the arrival and spread of invasives and to eradicate new populations of invasives

Increased incidence of infectious disease threatens wild and domestic species as well as humans. Transfer of disease between different species is a subject of special concern

Steps must be taken to prevent spread of disease in captive animals and to ensure that new diseases are not accidentally introduced into wild populations

Comprehensive conservation efforts must recognize that biodiversity faces multiple threats