Biology Topic 19: Conservation Biology

Importance of Biodiversity:

The life of the planet

––Provides us food, oxygen, building material, fiber, and medicine

––Helps maintain climate and weather patterns and weather patterns

–– Purifies air and water

It is estimated an ecosystems will stop functioning if __% or more of species disappear –

20%

Ecosystem Diversity

the variety of terrestrial and aquatic ecosystems

Interconnected ecosystems help______ each other

maintain

Benefits of healthy ecosystems

- Water and air purification

– Oxygen and food production

– Flood and landslide prevention

– Climate moderation

– Creation and preservation of soil

Value of Ecosystem Services

Crucial in maintaining life

• Global dollar value estimated at $33 trillion a year

• New York City bought land in the Catskill

Mountains that was the source of the city’s water

–– Water filtration plant to do the same job would to do the same job would

have cost $8 billion plus $300 million a year have cost $8 billion plus $300 million a year

Species Diversity

The number and abundance of different species

– Maintains food chains and healthy ecosystems

– Produces human resources like food and

medicines

•25% of US prescriptions first derived from plants

–– Pollination and soil fertility

–– Natural pest control

Genetic Diversity (= genetic variation)

The number and distribution of different alleles in

populations

– Maintains population health by diluting harmful

alleles

– Helps prevent extinction by allowing species to

adapt and survive in changing conditions

Terrestrial ecosystems are ________in many places.

–– Globally, we’ve lost almost half of all forests

–– Less than 22% of native US grassland remains

declining

Beach grooming

removes vegetation and dead seaweed which nourishes birds and wildlife

Freshwater fish make up _____________ of known fish species

over half.

25% of all freshwater fish face extinction

Globally, __% of coral reefs are gone and _% are damaged

50% ; 70%

Biodiversity Hotspots

Have many endemic species (found only there) and are are highly impacted by human activity

•Example: California biodiversity hotspot

Critically endangered

extremely high risk of extinction in very near future

Endangered

very high risk of extinction in near future

Extinct

no members of a species are left alive

How many periods of mass extinction are seen in the fossil record?

5, but we could possibly be in the 6th.

Extinction vortex

cycle of inbreeding and genetic drift that causes small populations to become smaller and go extinct

Small populations lose alleles by genetic drift

develop genetic disorders

loss of ability to respond to changing conditions

Leading causes of loss of biodiversity are:

1. Habitat Loss – biggest threat

2. Invasive Species – second biggest

3. Overharvesting – third

4. Global Changes

Habitat Fragmentation

• Remaining habitat areas become smaller and smaller

• divides populations so that

  genetic diversity is lost

• Individuals in different habitat fragments don’t

  encounter each other to mate

Non-fragmented habitats are almost__________.

non-existent

Globally, all biome habitat fragments except tundra are less than __% of their historical size

15%

Invasive Species

Invade a location in which they did not evolve

–– Compete with, prey on, or parasitize native species

–– Native species may lack defenses to the new invader

Overharvesting

Harvesting at rates that exceed population regeneration

Example of overharvesting

California groundfish

Examples of global changes caused by humans:

• nutrient enrichment

• toxin build-up

• climate change

Nutrient enrichment

People add nutrients made using fossil fuels to farmland, especially nitrogen and phosphorous.

“dead zone”

are created annually at river mouth

Biological magnification

toxins become concentrated, higher in food chain

Neonicotinoids

are killing insects and birds.

used in US to kill insect pests on crops.

toxic to bees and non-pest insects, causing the population to decline.

Climate change

caused by human air pollution and agriculture

The sea level has risen how many inches since 1880?

8-9”

Current Effects of Climate Change:

Fewer, more extreme rainfall events reduce crop yields

• Expanded disease ranges affect humans, wildlife, and livestock

• Heat and drought increase tree die-off

• Organisms must move, adapt, or die

–– Hundreds of species have declined, changed location, changed habits, or disappeared

• Many organisms cannot migrate rapidly enough or have nowhere to go

–– Mountain pikas dying off in western US

–– Caribou reproduction 4x less

Conservation Biology

Seeks to understand and counter biodiversity loss.

1. to maintain genetic diversity

2. to protect populations of threatened species

3. To sustain entire ecosystems and landscapes

Conserving genetic diversity

Global seed banks and zoo breeding programs help

In order to protect populations of threatened species, one must:

Must understand the niche of a species, its key habitat requirements and interactions

• Assess threats posed by human activity

• A plan is designed to expand or protect species’ needed resources

Global fisheries management is difficult because:

governments may disagree

Fisheries conservation

global attempt to stop subsidizing harmful fishing practices

Core reserves

protected areas within the landscape (only low impact activities like hiking,

etc). must be connected to reduce fragmentation

What is the 30×30?

Scientists believe that 30% of the land and sea needs to be protected by the year 2030

What type of communities protect 80% of global biodiversity?

Indigenous communities

Restoration ecology

seeks to return degraded areas to a more natural state

What type of food contributes the most emissions?

beef