habitat loss orange county, california. desertification desertification is the conversion of...
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Habitat Loss
Orange County, California
Desertification
• Desertification is the conversion of grassland and savanna habitat into relatively sparse, unproductive vegetation
• The main cause of desertification is overgrazing by livestock
RioPuercoBasinNM
Rio Puerco Basin
1885 1977
Rio Puerco Today
Overgrazing – Texas and England
Left good, right overgrazed Left good, right overgrazed
Wetlands
• Wetlands are lands that are transitional between aquatic and terrestrial ecosystems
Freshwater Wetland Types
General Locations of U.S. Wetlands
Crane Species
• 1. Eurasian Crane, 2. Black-necked crane, 3. Munktrana,
• 4. Sandhill Crane,
• 5. Whooping Crane, 6. Japanese crane, 7. White-naped Crane, 8. Sarus Crane, 9. Australian Crane, 10. Siberian Crane, 11. Wattled Crane, 12. Demoiselle Crane, 13. Blue Crane, 14. Black Crowned Crane,
15. Grey Crowned Crane
Grey Crowned Crane
Grey Crowned Crane
Habitat Fragmentation
• Fragmentation is the breakdown of a habitat or ecosystem into smaller patches of that habitat or ecosystem that now are isolated from each other
HabitatFragmentation
Island Biogeography
Charles Darwin and Alfred Russel Wallace
The Galapagos
Galapagos Tortoise
Galapagos Mockingbirds
Galapagos Mockingbirds collected by Darwin
Malay Archipelago
Beetles and Moths Collected by A.R. Wallace
Butterflies from Malay Archipelago
Sphingid Butterfly Diversity Malay Archipelago
IslandHabitats inBaltic Sea
Reptile and Amphibian Species Area Curve for Caribbean Islands
Habitat IslandsIn the Great Basin
Bird Species
Mammal Species
Species Area Curve
S = cAz
where:
S = number of species
A = area of island
c = constant for habitat type - forest, desert, grassland, etc.
z = slope of curve
Ant speciesOn NewGuinea andNearbyIslands
Real Slopes for Species-Area Curves
Oceanic islands birds - New Guinea islands z=0.22
beetles - West Indies z=0.34
land plants - Channel Islands z=0.37
Habitat islands birds - Andes paramo z=0.29
birds - mtns of Great Basin z=0.165
mammals - mtns of Great Basin z=0.326
inverts -caves in West Virginia z=0.72
Robert MacArthur and E.O. Wilson - originators of the Equilibrium Theory of
Island Biogeography
Ruffed Grouse by Audubon
Ruffed Grouse – male mating display
Apostle Islands – Lake Superior
Krakatau – before and after 1883 eruption
Aerial photo of Anak Krakatau and Krakatau
Krakatau today
Mangrove islands off the Florida coast
Mangrove Island Close-Up
Dan Simberloff on MandolinNick Gotelli on Guitar
Simberloff’s defaunation experiment on Mangroves
Simberloff’s defaunation experiment on Mangroves
Bracken Fern
Bracken Fern - Australia
Number of species found on Bracken Fern
Picture Winged Drosophila
Picture Winged Drosophila – more than 500 species from 1 ancestor
Picture Winged Drosophila – more than 500 species from 1 ancestor
• http://www.pbrc.hawaii.edu/research_news/
Cichlid Diversity
African Rift Lakes
Cichlids from Lake Tanganyika (left) and Lake Malawi (right)