conservation biology chapter 55. threaten species –chinese river dolphin –philippine eagle...
TRANSCRIPT
Conservation Biology
Chapter 55
• Threaten species– Chinese River Dolphin– Philippine Eagle– Less than 100 individuals remain
Threats to species
• Loss of habitat– Development of cities, suburbs– Agriculture, deforestation– local, feeding nesting etc. sites– tropical (distant) areas involved
with migratory species – Monarchs in Mexico
• Introduced species- competition– domestic dogs and cats, goats, cattle, foxes– Water hyacinth, Kudzo, Zebra Mussel– Brown Tree snakes in Guam– Caulerpa, Argentine ants, Africanized bees
• Loss of forest in Wisconsin
• Fragmentation of remaining areas
• Act like islands of forest
Fragmentation OR forests
Nile Perch- Africa Brown Tree Snake- Guam
Argentine Ants- California Caulerpa - California
• Zebra Mussel
Threats to Species
• Over-Exploitation of species– Hunting, timber harvest etc.– Most species are rare.– Many larger plants & animals are fewer in
number and reproduce slowly (low inherent growth rate) and can not recover quickly.
• Pollution - Pesticides and insects, amphibians
• Currently in a mass extinction
Polynesia andMicronesia
islandcomplex
Mediterraneanbasin
Caribbean
WesternGhats andSri Lanka
Philippines
Wallacea
NewCaledonia
Fig. 23.25, p. 617
TropicalAndes
CentralChile
BrazillianCerrado
Caucasus
Eastern Arc Mountainsand coastal forests
of Kenya and Tanzania
Cape Floristicregion of
South Africa
SucculentKaroo
Madagascar/Indian Ocean
islandsSouthwestAustralia
New Zealand
Polynesiaand
Micronesiaisland
complexIndo-Burma
Mountains of southcentral China
Guineanforests of
WestAfrica
Brazil'sAtlanticforests
Sundaland
Choco/Darien/western Ecuador
CaliforniaFloristicProvince
Meso-americanforests
What to save?
• We can’t save them all. Not enough $$ or land to save everything – Interests change with political climate– Population growth demands on local areas– More demand for exports in developing countries
– raw materials, energy
• What species to save? Choosing the fights to preserve an area.– Unique species - no closely related species (not
just another beetle)– Charismatic species - Giant Panda, Florida
Panther, Bald Eagle– Unique ecosystems
Park / Reserve Design• Best: Large, close- by reserves.
– Large round parks reduce edge effects– Increase immigration, population
migration (gene flow)
• Less desirable: many, small isolated preserves.
Park / Reserve Design
• Bigger is better – Many national parks have lost species
since their creation, even as the park area has expanded.
– The outside private lands have developed, thus reducing the the over all area.
– Mt. Rainier in 1920 = 73% of mammals remained by 1976 only 55% of original mammal species. Even though it has same area as original park.
Island Biogeography Ideas:
• Size of island influences survival rate– Larger islands sustain more species
• Nearness to other island influences immigration rate– Near islands have more species than
distant islands
• Island are any isolated habitat– Most parks are functionally islands.
Island Biogeography
• Larger islands sustain more species
Bio Reserve Model• Core - strict preserve, research.
– No human disturbances are allowed. – Very few such areas in US System – most
similar are our Wilderness Areas– Rounded to reduced edge effects.
• Inner Buffer - hiking, Some commercialization. – Ecotourism– Similar to most of our National parks today
• Outer buffer - (may not even be part of park) camping, concessions, grazing timber, agriculture.– Allows for nature outside park
Core
Fig. 23.26, p. 618
Core
• Round parks have less edge effect– Higher per cent
of park is in core area
Edge effect
• Natural vs. Artificial edges
Biosphere Reserve
Core area
Inner Buffer
Outer Buffer
Fig. 23.27, p. 620
One Species
Three Species Overlap
Two Species Overlap
Existing Nature Reserves
Naalehu
Hilo
Kona
Fig. 23.28, p. 621
Bio Reserve Model
• Corridors connect core areas from park to park forming land bridges
• May be like outer buffer with agriculture, forestry.
• Our national Forests serve this role in many areas of the west.
• Except for areas designated as wilderness (need permits to access them) U.S. system is one of multiple use (inner buffer) at every level.
Endangered and Threatened Species
• Endangered species
• Threatened (vulnerable) species
• Rare species
Florida manatee
Northern spotted owl (threatened)
Gray wolf Florida panther Bannerman's turaco (Africa)
Fig. 22.7a, p. 556
Land Use
• About 40% of our land is in public trust. – Distribution is unequal! – Western States have many more acres in
parklands, forest than East Coast.
• Very little is actually protected– 15% as wilderness.
• Species conservation has to fight with - timber, hunting, farming, grazing, oil exploration, etc..
Urban 2%
Tundra and wetlands 9%
Desert 20%
Cropland 11%
Rangelandand pasture26%
Fig. 23.2, p. 586
Forest32%
U.S. Land Use
Forest30%
Parks,wildlife refuge,wilderness 9%
Desert, tundra,wetlands 13%
Urban 2%
Cropland 17%
Rangelandand pasture29%
Fig. 23.3a, p. 586
U.S. Land Ownership
Federal35%
Private55%
Native American 3%
State and local 7%
Fig. 23.3b, p. 586
National parks and preserves National forests National wildlife refuges
Fig. 23.4a, p. 587
National parks and preserves National forests National wildlife refuges
Fig. 23.4b, p. 587
Mineral / Energy Resources
• Many of the federally protected lands many rich supplies of minerals
• Extraction of these resources would add further stresses on ecosystems
• Artic Refuge the current target– want to open up protected areas for oil
exploration
• California off-shore oil-beds also threaten with development
• Needs of the populations vs. preservation
Moderate mineral deposits
Rich mineral deposits
Federal landFig. 23.5a, p. 588
Moderate mineral deposits
Rich mineral deposits
Federal land
Fig. 23.5b, p. 588
National Parks and Monuments
• Started in US - 1864 - Yosemite – protected by Abraham Lincoln during Civil War. – Turned over to State of California to administrate.
• 1872 Yellowstone First National Park – – United States Federally administrated park
• Yosemite and Sequoia Kings canyon in 1890. – Each was founded independently by an act of congress.
• 1906 Congress gave President authority to set aside areas of scientific, historic or cultural value as national Monuments.– Teddy Roosevelt used this to establish many reserves
Early National Park System• Loosely managed by US Army to protect lands
form hunters, loggers etc.– Yosemite was patrolled by cavalry at first.
• Until 1916 when National Park Service was established to better protect parks, – in part as a response to Hetch Hetchy dam in Yosemite.
• National Park concept has spread around the world, some say it America’s best invention.
• Originally just natural areas • Now have expanded to include many more
historical (battlefields) and cultural sites (Pueblo).
National Parks• After cars made visiting easier, NPS stressed the
visitors pleasures more than natural environment. – Camp Curry in Yosemite shows would draw over 2,000
nightly. – Had fire falls, bear feedings, Jazz bands, toboggan runs
etc.
• California has the most National parks with 23. • Many states have none, causing a political
problem.• New Ideals stress Rangers as nature interpreters,
and preservation as top priorities• Unfortunately many Rangers have become more
like police in some areas.
National Parks
• Seem large (miles across) but are often too small for the larger animals to maintain a viable number of individuals.
• Yosemite has limited access (closed when full). – Most visitors don’t stray far into the wild. – 95% of visitors don’t venture past Yosemite Valley floor
which is less than 1% of the park’s area. – Park becomes crowded, dusty, smoky etc.
• Yosemite Valley Plan• Yellowstone only has 100 grizzle bears.• Most Parks are generally over-crowded and under
funded
National Parks
• Restoration -– allowing forested areas return to old growth
without logging.
• Reintroduction of native species – – wolves in Yellowstone, Great Smokey
Mountains, Arizona– Restoration projects in meadows, marshes
National Wildlife Refuge System
• 1964 Wilderness Act- areas of federal land that are to be managed to retain its:– primeval character with no commercial
enterprise, no permanent road, and no motorized vehicles
• Many are set up to protect migratory bird areas.
Other Parks• State Parks, Beaches
– Mt Diablo- Mitchell Canyon– Bodega Shoreline – Sonoma County State
Beaches
• East Bay Regional Parks (EBRPD)– Founded in 1934. – Includes: Briones, Redwood– 50 parks, shorelines and lakes; 20 trails.
Totaling more than 75,000 acres.– Alameda and Contra Costa Counties (once one
county-parks remained joined)
• City Parks- mostly for recreation not nature reserves
Private Reserves- Nature Conservancy • Highest level of protection is private ownership.
– founded by Ecological Society of America, college professors.
– Largest private land owner in US. In 1999 had 7 million acres. 78% on Biologically significant sites.
– Other land donated may be sold / exchanged for more biologically significant sites later.
– Able to purchase high price lands.– 286 square miles of unbroken forest in Maine for $35
million
• 14,000 acres of CO wetlands for $4.5 million. • Easements - sold to owner.
– Doesn’t change ownership of land, but restricts future development.
Private Reserves
• Started by Ducks Unlimited
• Other hunting groups
• Local interest groups– Friends of Mt. Diablo– Save the Redwoods– Many Others
Zoos• Originally just for our pleasure
• Now for many a last resort -
• Animals are Safe, but in artificial habitat
• Is it ethical ? – free roaming animals, trapped in small
enclosures, tanks. – Captive vs. Extinction?
• Animal’ s visitors pay most of the bills.
• Animals bred in captivity without (or reduced) natural rearing.
Zoos• Different for different animals,
– some don’t live long in captivity. – Most live longer, but quality of life?
• Sincerely trying to mimic wild conditions-– not fed everyday.– larger multi-species enclosures– play, hunting activities.– changes in habitat design,– rotating into different areas.
• For many no longer a choice, a necessity as home ranges disappear.
• Genetic resource for breeding in captivity
Zoos• Potentially can reintroduce in new or restored
areas. Success stories: – Whooping Crane. – California Condor– Peregrine Falcon
• Cryogenic storage of sperm. – ova to increase genetic diversity in future pops. – Used for endangered populations, with high resource
availability, – allow for artificial insemination between zoos without
moving animals. Less risk of harm, disease
• Cloning – first was a banteng in April 2003– Used cells preserved in deep freeze from an animal that
died years earlier
Botanical Gardens• No ethical problems, costly to maintain.
– Not as lucrative as zoos – Some are being combined with zoos.
• National Seed Storage Laboratory in Fort Collins CO. – Mostly for commercial lines. – Loss of local, heritage vegetable crops.
• Many of the potatoes and tomatoes in UC Davis storage are now extinct in the wild.
• Millennium Seed Bank Project- United Kingdom has a group to preserve seeds / spores from all of its native plants