Biodiversity & Conservation Professor Andrea Garrison Biology 3A Illustrations ©2014 CENGAGE Learning

Ecosystem Services • Ecosystems important to our well-being – Provide us with variety of direct and in direct benefits (valued as high as $33 trillion) • Source of food and genes • Source of medicines • Natural pest control and pollinators • • • • •

Jobs Natural processes purify our water and air Carbon sequestration Flood and erosion control Recreation Biodiversity & Conservation

2

Ecosystems & Biodiversity • Healthy ecosystems have high biodiversity – Species richness, genetic variation

• Biodiversity keeps ecosystems functioning – At level of communities, ecosystems and biosphere

• Biodiversity has intrinsic value – Humans just one of millions of species – People often emotionally/spiritually connected to natural landscapes, etc. – Biodiversity enhances our existence beyond its direct and indirect benefits to us Biodiversity & Conservation

3

Threats to Biodiversity • Species extinctions decrease biodiversity • Important to protect species; especially endangered and threatened species – 1973 U.S. Endangered Species Act defines an endangered species as a species that is “in danger of extinction throughout all or a significant portion of its range”

Biodiversity & Conservation

4

Threats to Biodiversity • Habitat destruction – Deforestation

Biodiversity & Conservation; Illustration ©2010 Pearson Education, Inc.

5

Threats to Biodiversity • Habitat destruction – Desertification results from clearing or overgrazing large tracts of land – Loss of vegetation • • • • •

More runoff in rainy season Groundwater table recedes Less surface water results in less plant life Soil accumulates high concentrations of salt (if irrigated areas) Topsoil erosion

– Previously vegetation rich habitat becomes desert

Biodiversity & Conservation

6

Threats to Biodiversity • Habitat Fragmentation – Human land use breaks up natural habitat into smaller areas divided by roads and cities – Smaller patches of intact habitat • Sustain smaller populations of organisms – Lower carrying capacity – Problem for higher trophic levels

• Many species won’t cross roads, etc. – Reduced gene flow between populations

• Edge effects further decrease habitat area Biodiversity & Conservation

7

Threats to Biodiversity • Edge effects – Human activities at borders of habitat disrupt quality of habitat • Noise • Pollution • Extra sunlight, wind, rain at edge of forest

Biodiversity & Conservation; photos ©2013 Pearson Education, Inc.

8

Threats to Biodiversity • Edge effects – Habitat fragments have more edge effects than larger regions of habitat

Biodiversity & Conservation

9

Threats to Biodiversity • Invasive (exotic) species – Outcompete and prey on native species

Biodiversity & Conservation

10

Threats to Biodiversity • Invasive (exotic) species – Introduce diseases to which native species have no previous exposure, no resistance – Devastating outbreaks • Ex: chytrid fungus infection is at least partially responsible for drastic declines in amphibian population world-wide (along with habitat destruction and pollution) – Traced back to African clawed frogs imported for biological research and the pet trade – Biologists hypothesize that climate change has facilitated the growth of the fungal species over the last 35 years

Biodiversity & Conservation

11

Threats to Biodiversity • Overexploitation – –

Sport or commercial hunting and fishing beyond sustainable levels Poaching protected animals for fur or body parts

Biodiversity & Conservation; Illustration ©2010 Pearson Education, Inc.

12

Kiyoshi Kimura, president of company that runs a sushi restaurant chain, poses with 220 kg bluefin tuna at Tsukiji Market, Tokyo, Jan 5, 2016. Kimura bid 14 million yen (almost $120,000) for the tuna. (Hiroto Sekiguchi/AP; from CNN; http://www.cnn.com/2016/01/08/world/gallery/week-inphotos-0107/index.html)

Threats to Biodiversity • Air pollution

Biodiversity & Conservation

14

Threats to Biodiversity • Water pollution – Toxic chemicals – Eutrophication • Nutrient runoff in agricultural watershed

Biodiversity & Conservation

15

Threats to Biodiversity • Water pollution – Nutrient run-off in agricultural watershed – High algal growth – Decomposition of algae as they die uses up oxygen (dark blue indicates lack of life)

Biodiversity & Conservation

16

Threats to Biodiversity • Global climate change

Biodiversity & Conservation; right photo Hurricane Sandy, ABCNEWS.com; left photo http://www.commodityonline.com/news/cashing-in-on-drought-challenges-the-bofaml-way-50968-3-50969.html

17

Threats to Biodiversity • Hydrologic alteration – Building massive dams – Redistributing water to where humans want it – Freshwater ecosystems among most endangered on earth

Biodiversity & Conservation

18

Threats to Biodiversity • Hydrologic alteration – Changes rate and volume of water flowing in river • Less, slower water downstream • Seasonal changes in water flow become more regulated

– Disrupts life histories of aquatic organisms adapted to natural river • Cold water from depths is brought to surface • Interrupts spawning and other temperature regulated activities of organisms

– Reduces connections between streams and rivers • Interrupts upstream fish migrations for spawning

– Facilitate introduction of nonnative species that thrive in disturbed habitat

Biodiversity & Conservation

19

Threats to Biodiversity • Biodiversity hotspots – Places identified by scientists as having high biodiversity endangered by human encroachment – Areas with at least 1500 endemic species (found nowhere else) and having lost at least 70% of its natural vegetation – # has grown from 25 to at least 34 areas since 2000 – Represent 1.4% of earth’s land surface – Include only remaining habitat for 45% of all terrestrial species and 35% of all terrestrial vertebrate species Biodiversity & Conservation

20

Threats to Biodiversity • Most biodiversity hotspots in heavily populated areas – Difficult to manage for the preservation of species

• Biologists looked for areas that would provide best outcome for their investment – Identified 595 sites of imminent extinction, with total 794 endangered species; each site: • Must have at least one species recognized as endangered by the World Conservation Union • Must contain at least 95% of the world population of that species • Must have clearly defined boundaries that separate it from surrounding areas (easier to manage species at the site) – Lakes, mountain tops, forest fragments

– 33% of sites lie completely within protected areas – 40% of sites have no protection – Biologists working to protect these sites and their species

Biodiversity & Conservation

21

Sites of Imminent Extinctions

Biodiversity & Conservation

22

Conservation Biology • Focuses on maintenance and preservation of biodiversity • Uses theoretical concepts from biological disciplines of systematics, population genetics, behavior and ecology

Biodiversity & Conservation

23

Conservation Biology • Systematics – Conservation plan for any area requires inventory of species • • • •

Daunting task 1.6 million species named and described Estimated 30 – 100 million living species How to inventory species when up to 98% of them have no name?

Biodiversity & Conservation

24

Conservation Biology • Population genetics – Endangered species have small population sizes • Genetic drift usually reduces genetic diversity within the population – Reduces potential to adapt to changing environment

– Biologists work to increase population size and genetic diversity • Breeding programs carefully monitored to prevent inbreeding

Biodiversity & Conservation

25

Conservation Biology • Ex: whooping crane – Once abundant in wetland areas of Midwestern U.S. – Overhunting and habitat destruction caused numbers to decline to 21 individuals in two isolated populations – Population bottleneck, loss of genetic variability • Developmental deformities of spine and trachea Biodiversity & Conservation

26

Conservation Biology • Ex: whooping crane – Aggressive conservation program • Preserved habitats within winter and summer ranges • Captive breeding program designed to minimize effects of inbreeding • Currently >300 individuals in wild and captive populations • Still have very low genetic variability Biodiversity & Conservation

27

Conservation Biology • Population ecology and behavior – Conservation programs require understanding of target species’ feeding habits, mating habits, predators, habitat preferences, movement patterns, space requirements and reproduction rates – Population viability analysis (PVA) required • Complex computer modeling • How large must population be to ensure long-term survival (95% chance of surviving 100 years) – Examine factors which may influence longevity of the population » Habitat suitability » Likelihood of catastrophes in habitat » Gene flow between populations » Other factors which influence population demographics, size or genetic variability

• Identifies minimum viable population size – Smallest population size that fits specifications of conservation plan

Yellow-bellied glider (marsupial)

– Always a risk • If you transplant 50% of living individuals of an endangered species and program fails, there are even fewer of that species left Biodiversity & Conservation

28

Conservation Biology • Community ecology – Large regions of habitat contain more species than smaller regions • Higher carrying capacity • Smaller edge effects

– Beyond a certain area, adding area doesn’t increase species richness (all species in area are represented) – What is the right size area for the species under consideration? – Is it physically and politically possible to get that much land set aside?

US Threatened; IUCN Endangered (Int’l Union for Conservation of Nature)

Biodiversity & Conservation

29

Conservation Biology • Landscape ecology – Design geometry and size of protected areas – Analyze large-scale ecological factors • Distribution of vegetation, topography, human activity • Large area vs smaller patches? – Large area increase species richness – Smaller patches connected by corridors seem to increase native plant species richness – Corridors also allow animal movement between patches – Corridors do not promote entry of exotic species

Biodiversity & Conservation; photo ©2013 Pearson Education

30

Conservation Biology • Alpha diversity – Biodiversity within well-defined communities

• Beta diversity – Conservation biologists concentrate of this – Biodiversity within area having wide variety of habitats and vegetation types – Larger areas increase species richness (preserve greater # spp in the reserve area) • Perhaps because they are more likely to include more environmental diversity • Global climate change also increases need for variation of altitude within protected areas Biodiversity & Conservation

31

Conservation Biology • Practical strategies – Preserving species (in nature) requires preserving ecosystems – Integrate biological research with economic and social realities – 3 approaches • Preservation • Mixed use conservation • Restoration Biodiversity & Conservation

32

Conservation Biology • Preservation – Set aside sensitive habitat where biodiversity is threatened – Strict standards must be enforced for land use • Sometimes people are totally excluded • Sometimes access is restricted and resource exploitation controlled

– Requires enforcement capabilities • Works well in developed nations

Biodiversity & Conservation

33

Conservation Biology • Mixed-use conservation – Protect some land parcels and allow controlled use of others – Ngorongoro Conservation Area (Tanzania) • Tourist attraction • Maasai people herd cattle and goats here – Nomadic; move frequently, no permanent damage to habitat – Maasai agreed to leave Serengeti National Park in return for right to remain in NCA; govt helped create infrastructure (water access) in NCA – 40,000 people live in NCA without damaging habitat

Biodiversity & Conservation

34

Conservation Biology • Restoration – Reestablish health of disrupted ecosystem • Remove any contaminants, impediments to natural water flow, barriers to animal movement, etc. • Restore natural processes such as periodic fires, floods • Replant key plant communities • Long-term management

Biodiversity & Conservation; banner http://panoramavista.org/

35

Conservation Biology

• Requires local support and involvement – Works best if preservation of the habitat provides local residents with some benefit • Jobs as park wardens • Ecotourism

Biodiversity & Conservation

36