APES 11

What decreases biodiversity?

Large or catastrophic disturbances, drastic decreases of a nutrient, extreme habitat changes, non-native species introduction, geographic isolation

How much faster is the current extinction rate due to humans?

Almost 10,000 times the natural rate

Approaches for biodiversity protection

Species approach, ecosystem approach, wildlife approach, legal approach

Goal of the species approach

Protect species from premature extinction

Strategies of the species approach

Identify endangered species, protect their critical habitats

Tactics of the species approach

Legally protect species, manage habitat, propagate in captivity, reintroduce into wild

Local extinction (extirpation)

Loss of population in one area, but still exists elsewhere

Ecological extinction

So few members remain that the species no longer fulfills its ecological role

Biological extinction

The species no longer exists anywhere on Earth

Instrumental values of biodiversity

Utilitarian, economic goods, ecological services, recreation

Examples of economic goods from biodiversity

Food, fiber, fuel, lumber, medicine, paper

Examples of ecological services from biodiversity

Photosynthesis, water/air purification, pest control, pollination, waste decomposition, climate regulation, soil formation, nutrient recycling, flood control

How much is spent annually on outdoor recreation in the U.S.?

$887 billion

Non-utilitarian values of biodiversity

Existence, aesthetics, bequest

What is the conservation status list called?

The International Union for the Conservation of Nature (IUCN)

What does 'Extinct (EX)' mean?

No known individuals remaining anywhere

What does 'Extinct in the Wild (EW)' mean?

Species only survive in captivity or cultivation

What does 'Critically Endangered (CR)' mean?

Extremely high risk of extinction in the immediate future

What does 'Endangered (EN)' mean?

High risk of extinction in the near future

What does 'Vulnerable (VU)' mean?

High risk of endangerment in the medium term

What does 'Near Threatened (NT)' mean?

Conservation Dependent (CD)

Species would be threatened if conservation programs were stopped

Least Concern (LC)

Low risk; widespread and abundant

Causes of species extinction

Background extinction, mass extinctions, and extinction spasms

Why is extinction difficult to confirm?

Few species have regular counts, rare species are hard to locate, and some may exist elsewhere

Species-area relationship

Estimating extinction rates based on habitat loss

Population Viability Analysis (PVA)

Predicts population persistence using habitat, genetics, interactions, and reproduction

Minimum Viable Population (MVP)

The smallest number of individuals needed for long-term survival

Typical number of individuals needed for MVP

Several thousand

Minimum Dynamic Area (MDA)

The minimum area of habitat required to support MVP

Island biogeography

Species diversity and extinction based on island size and isolation

Latitudinal species diversity gradient

Species diversity increases closer to the equator

Effect of tropical rainforest destruction rate on extinction

Accelerates species extinction due to habitat loss

Current extinction rate due to humans

10,000 times higher than natural background rates

Habitat fragmentation

The breaking up of habitats into discontiguous or smaller patches

How habitat fragmentation threatens species

Makes animals more vulnerable to predators, reduces viable population size, limits movement for food and mates

Habitat loss

Complete removal of natural habitat, preventing native species from repopulating the area

What happens when habitats are exposed?

Animals become more vulnerable to predators, invasive species, wind, and fire

Result of small or isolated patches from fragmentation

They may not support genetically healthy populations

Barriers created by fragmentation

It limits species' ability to colonize, find food, and find mates

Non-native species

Species introduced to new areas where they have no natural predators

Why do non-native species become invasive?

Their population can explode and outcompete native species

How to prevent invasive species

Identify sensitive ecosystems, inspect imports, identify invaders, pass international laws

How ballast tanks reduce invasive species

Ships should flush in open sea, sterilize tanks, or use nitrogen to prevent contamination

Hunting and poaching

Illegal killing and trading of animals like leopards, elephants, and tigers

Tiger population in 1950

100,000

Current tiger population

Fewer than 5,000

Elephant population in 1970

2.5 million

Current elephant population

Around 300,000

Overfishing

Excessive removal of fish from ecosystems, threatening marine biodiversity

Drift net fishing

Bycatch

A fishing method where 7/8 of the catch may be unintended bycatch

Threatened species characteristics

Species more likely to be threatened include those that are: Rare, slow to reproduce, need large areas, have specialized niches, or are desirable for use

Climate change threat to species

The environment changes faster than species can evolve

Wildlife habitat alteration by 2100

One third of global wildlife habitat may be altered

Species needs identification

Distribution, population status, habitat requirements, intraspecies relationships

Bioinformatics

The development of software tools to interpret biological data

Fields combined in bioinformatics

Biology, computer science, mathematics, engineering

Legal approach to biodiversity protection

Using international treaties and national laws to prevent the trade of endangered or at-risk species

CITES

Convention on International Trade in Endangered Species

CITES signing year and countries

Signed in 1975 by 152 countries

CITES prohibitions

Trade or sale of 900 species; restricts trade of 29,000 others at risk

Problems with CITES

Difficult enforcement, members can opt out, small fines, trade occurs in non-member countries

Convention on Biological Diversity

An international agreement signed by 172 countries to conserve biodiversity

Goals of the Convention on Biological Diversity

Conservation, sustainable use, and fair sharing of benefits from genetic resources

U.S. laws controlling endangered species

The Lacey Act of 1900 and The Endangered Species Act of 1973

Lacey Act

Restricts the transport of wild species or their parts across state lines without a federal permit

Endangered Species Act (ESA)

U.S. law signed in 1973 to protect endangered and threatened species of fish, wildlife, and plants

Organizations enforcing ESA

National Marine Fisheries Service (NMFS) and U.S. Fish and Wildlife Service (USFWS)

Threatened or endangered species count (2018)

2,340 species were listed as threatened or endangered as of 2018

Species recovered since 1967

53 species recovered; 11 de-listed due to extinction

Habitat Conservation Plans (HCPs)

Allow developers to set aside habitat, relocate species, or fund habitat preservation elsewhere

Safe Harbor Agreement

Landowners maintain or restore habitat for endangered species in return for support from agencies

Voluntary Candidate Conservation Agreement

Similar to Safe Harbor but for species not yet listed as endangered or threatened

Ways the ESA has been weakened

Make protection voluntary, force government to compensate landowners, limit public opposition, shift power to Secretary of the Interior

Improving the ESA

Increase funding, develop recovery plans faster, use science-based policies, define emergency habitats

Additional ESA improvements

Protect ecosystem function, identify at-risk ecosystems, incentivize landowner participation

First U.S. federal wildlife refuge

Pelican Island, designated by Roosevelt in 1903

Protected acres in U.S. wildlife refuge system

150 million acres are now protected in the U.S. wildlife refuge system

Number of national wildlife refuges

560 refuges

Wildlife refuges

Over 380 threatened or endangered plant and animal species

Role of wildlife refuges for birds

Serve as rest stops for migrating birds

Annual visitors to refuges

47 million

Economic benefit from refuge visitors

$2.4 billion annually

Obtaining refuge lands

Purchased outright, leased fully or partially, or acquired as an easement

Conservation easement

A legally binding agreement that restricts land use to protect resources while remaining privately owned

Seed banks

Facilities where seeds are preserved for future use

Egg pulling

Removing eggs from the wild and hatching them in captivity

Captive breeding

Breeding endangered species in controlled environments to increase population

Techniques for population replenishment

Artificial insemination, embryo transfer, cross-fostering, and genetic cloning

Artificial insemination

Injecting sperm into a female to aid reproduction

Embryo transfer

Implanting a fertilized embryo into a surrogate mother

Cross-fostering

Raising offspring by a surrogate parent of a similar species

Genetic cloning

Creating a genetically identical copy of an organism

Wildlife management

Hunting and fishing laws, harvest quotas, habitat improvements, and population plans

Treaties for migrating birds

International treaties used in wildlife management

Ecological succession

Natural change in the structure of a species community over time

Importance of diverse habitats

They attract and support a variety of wildlife species based on needs for food and shelter

Population dynamics

Study of how populations change over time

Maximum sustainable yield

The largest number of individuals that can be harvested without reducing future population sizes