Conservation Biology

Conservation Biology

Biodiversity

Trophic LevelsPrimary ProducersPrimary ConsumersSecondary ConsumersTertiary ConsumersQuaternary Consumers

Trophic LevelsPrimary ProducersPrimary ConsumersSecondary ConsumersTertiary ConsumersQuaternary Consumers

Keystone Species

Keystone Species

Keystone SpeciesCoyote –Keystone species in Walnut

Killing coyotes means an increase in a few dominant species Residents complain about rodent problems when coyotes disappear

Biodiversity – Number of Species?

Biodiversity Levels

Genetic SpeciesCommunity and Ecosystem

Biodiversity Levels

AlphaNumber of taxa in a local area

GammaNumber of taxa in a region

BetaThe turnover of species from one habitat to another

Geographic Patterns in Species Diversity

Latitude60 degrees N40 degrees N20 degrees N

Ant Species10 species50 – 100 species100 – 200 species

Geographic Patterns in Species Diversity

CountryGreenlandNew YorkGuatemalaColombia

Bird Species56 species105 species469 species1395 species

Bird Diversity in North and Central America

Geographic Patterns in Species Diversity

Location

Arctic WatersTemperate WatersTropical Seas

Marine Species (Tunicates)

100 species400 species600 species

Latitude BeltsTemperate Zone Habitats

MarshGrasslandShrublandDesertConiferous ForestsUpland DeciduousFloodplain Deciduous

# of Bird Species (E. J. Tramer)

661414172124

Foliage Height DiversityAdding new layers adds new habitats for additional species

North American Diversity (MacArthur and MacArthur)

Mammals and Breeding Land Birds

Increase from North to SouthMore in the west

• Increases with heterogeneity

Reptiles and Amphibians

More abundant in East• Reptiles – mountains• Amphibians - water

Island BiogeographyMacArthur and Wilson (1960’s)

Primary ProductivityThe amount of light energy that is converted into chemical energyOften expressed as biomass

Pyramid of Net Productivity

Secondary ProductivityThe rate at which an ecosystem converts the chemical energy of the food they eat into their own biomass10% rule

Biodiversity Crisis

Extinction Rates are increasingToxins (biological magnification)Greenhouse effect / Ozone depletionOverpopulation

Major threats to BiodiversityHabitat DestructionOverexploitationIntroduction of exotics

ConservationEndangered Species

in danger of becoming extinctThreatened Species

likely to become endangered in the near future

Genetic DiversityLosing individuals or populations loses genetic diversity

Habitat Fragmentation

ConservationEdgesCorridorsProtect landscapes not individual speciesSustainable development

Edge Effect

Corridors

Population Viability AnalysisPredicts whether a species will persist in an environment

minimum viable populationeffective population size

ExtinctionBackground

Several species a year just go extinct – They are replaced

MassLarge scale extinction – species replaced due to adaptive radiation of remaining species

AnthropogenicLarge scale extinction – species being replaced by a single species (humans)