Today: Global and local Conservation issues. It s s the end of the world as we know it (R.E.M) Wednesday: Conservation solutions. Once upon a time 1
And then. Global warming Fires Increased development Agricultural Exploration Agricultural revolution Ayres Ed, 1999. Gods Last Offer: Negotiating for a sustainable future. The world today seems absolutely crackers. it s depressing and it s senseless (Monty Python) Just some of the hundreds of similar newspaper headlines: One Quarter Of All Mammal Species Face Extinction Soon (IUCN-- 2000) Monkeys, Apes Are Being Eaten to Extinction (Associated Press) Mass Extinction of Freshwater Creatures Forecast (WWF Report) 90% OF ALL LARGE FISH GONE FROM WORLD'S OCEANS (Nature-- 2003) North Sea Undergoing Ecological Meltdown (U.K. Independent) Amphibians Declining Worldwide (Boston Globe) Reptiles Vanishing Faster Than Amphibians (CNN) Migratory Birds and Animals Rapidly Dying Out (Environment News Service) Forests Face Global Extinction (United Nations) 1000's Of Medicinal Plants Being Harvested to Extinction (Australian Broadcasting Co.) 25% Of World's Conifers Threatened With Extinction (IUCN) One in Eight Birds Face Extinction (BirdLife International) 90 Percent of Great Ape Habitats Will Be Destroyed by 2030 (United Nations) 2
Ecological threats: Habitat degradation Species loss Habitat loss * Exotics affecting the natural species in a habitat. * Coevolutionof species with humans. Species-Area curves (SPAR) 3
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5 Loss of habitat => loss of species
Loss of species =>loss of more species Obligate mutualism Symbionts Food webs (predation, competition) Keystone species (may lead to collapse of entire system). Species gain: Coevolution of species with humans Harmless: peppered moth of England Harmful: more virulent strains of viruses or bacteria etc. (e.g. the flue). 6
Examples of Habitat loss and degradation: World s tropical rainforests are disappearing at a rate of 160,000 square km. per year! The Atlantic coastal Rainforest of Brazil used to cover 12% of Brazil s area; today 93% of this forest has been cleared! Brooklyn, NY ~1925 7
The Atlantic Coastal Rainforest of Brazil (450 tree sp./ha. highest richness on earth) 1945 85.4% of Bahia state was forested =2,235,900 hectares 1960 over half was cleared 1974 Over ¾ cleared 1990 94% cleared!!! Only 164,825 hectares remain!!!! 8
Loss of species: Keystone species. Aesthetical: Pandas, hummingbirds Medicinal value: Various plants. Economic: food species, fibers etc. (e.g. Nature. 1997: the economic value of ecological services such as soil formation, water filtration, biological control of pests, and production of oxygen far exceeds the value of the entire human economy. Bees, and other wild insects, for example, pollinate about 80% of the world's major crops, other than grains... the bees, too, are disappearing. Ayers, God s Last Offer) New and yet unknown species: (e.g. Discovery of new monkeys in the Forests of North Congo. chimpanzee and gorilla mix?; The Bigfoot / Yeti) The Species Extinctions Spike 1.75 Mio species have been described, but 13-14 Mio may exist. The current extinction rate may be 100 to 40,000 times higher than the background level. The current era of mass extinction may have begun 50,000 to 10,000 years ago, the Pleistocene Extinction or the Homocene Extinction. 9
Statistics of species loss: IUCN Red List (Global) ESA (Endangered Species Act) listed species and extinctions (USA) IUCN The World Conservation Union Red List About 140 countries are members in the IUCN. Founded in 1948. Mission: to influence, encourage and assist societies throughout the world to conserve the integrity and diversity of nature and to ensure that any use of natural resources is equitable and ecologically sustainable. The Red List is an assessment of the conservation status of species and populations on a global scale. 10
Endangered Species Act (ESA) Passed by Congress in 1973. After realizing that many organisms are in danger of becoming extinct and acknowledging that: the natural heritage is of esthetic, ecological, educational, recreational and scientific value to our nation Purpose: to conserve and recover listed species and the habitat on which they depend. Administered by the U.S. Fish and Wildlife Service (FWS) and the National Oceanic and Atmospheric Administration (NOAA)-Fisheries. Tucson Bird Count human influence Human avoiders (Will Turner. www.tucsonbirds.org) 11
Tucson Bird Count human influence Human followers (Will Turner. www.tucsonbirds.org) Endangered and Extinct species examples: 12
Some Endangered Species of Arizona (list taken from: Official World Wildlife Fund Guide to Endangered Species of North America. Washington D.C.: Beacham Publishing Inc., 1990.) Ed. John R. Matthews. Plants (12 sp.) Arizona agave (Agave arizonica) Birds (4 sp.) Northern aplomado falcon (Falco femoralis septentrionalis) Fish (17 sp.) Apache trout (Salmo apache) Reptiles (1 sp.) Desert tortoise (Gopherus (=Xerobates) agassizii) Mammals (6 sp.) Sonoran pronghorn (Antilocapra americana sonoriensis) The Palila - Endangered A large Endangered finch found only on Hawaii, USA. The species was abundant on the island until the beginning of the twentieth century. However, it is now restricted to a very small range and its subalpine forest habitat continues to decline due to severe overgrazing by feral ungulates and invasion of introduced weeds. Nestlings are also preyed upon by Shorteared Owls, feral cats and introduced rats. 13
The Cucumber Tree - Vulnerable An unusual Vulnerable endemic from the island archipelago of Soqotra, Yemen. The species is very well adapted to withstand drought conditions and should therefore be better able than many species to tolerate any drying out of the Archipelago due to climate change. However, in times of severe drought, trees are cutdown, pulped and fed to livestock, and in some areas this has resulted in its almost total eradication. Declining habitat quality is also preventing regeneration of the plant. The Anegada Ground Iguana - Critically Endangered Was once distributed over the entire Puerto Rico Bank, but today is confined to the island of Anegada in the British Virgin Islands. The iguana is susceptible to predation by humans and their dogs and cats and it is believed that this may have resulted in the contraction in the species range. It is listed as Critically Endangered and a reintroduction program is currently in place. 14
First sighted around 1600 on Mauritius, an island in the Indian Ocean, the Dodo was extinct less than eighty years later. Some of the birds may have been eaten by the Dutch sailors who discovered them. However, the primary causes of their extinction were the destruction of the forest (which cut off the Dodo's food supply), and the animals that the sailors brought with them, including cats, rats, and pigs, which destroyed Dodo nests. (American Museum of Natural History) Dodo - Extinct Passenger Pigeons - Extinct lived in the eastern United States from Canada to the Gulf of Mexico. They migrated across this range in numbers so huge that their flocks darkened the sky. A writer once described a migrating flock as "a column, eight or ten miles in length... resembling the windings of a vast and majestic river." In 1808 a single flock in Kentucky was estimated to contain over 2 billion birds. Today, in a stunning example of the human potential for destruction, the Passenger Pigeon is extinct. The last one, which lived in the Cincinnati Zoological Garden, died on September 1, 1914. (American Museum of Natural History) 15
6 floral kingdoms: 1. Holarctic Kingdom: 42% 2. PaleotropicalKingdom: 35% 3. Neotropical Kingdom: 14% 4. Australian Kingdom: 8% 5. Holantarctic Kingdom: 1% 6. Capensis: 0.04% (Cape Kingdom) Fynbos (South Africa s Western Cape Province) 16
Fynbos plants Area of 90,000 km 2 8,500 plant sp. 68% endemic Homework for Monday: Read The Lorax by Dr. Theodore Geisel (3 copies in the reserves of the library). Suggest one possible strategy to get a Happy end for the book. (how would you rewrite the story in the first place so it s happier, or how would you change the end of the current book?) Email me your short answer by Monday evening alona@email.arizona.edu 17