Types of Extinction

1. Types of Extinction • 1. Local Extinction: occurs when a species no longer occurs in area where it was once found • 2. Ecological Extinction: occurs when so few members of a species are left that it can no longer play its ecological role where it is found • 3. Biological Extinction: occurs when a species no longer occurs anywhere on Earth. Examples:

2. Passenger pigeon Dusky seaside sparrow Great Auk Dodo Aepyornis (Madagascar) Fig. 22.6, p. 555

3. Mass Extinction vs. Background extinction Background extinction : extinction is a natural process, each year a relatively small number of species become extinct naturally. The average is about one species per million per year. .0001% Mass extinction is when there are periods when many organisms become extinct over thousands of years. These are followed by periods of adaptive radiation when diversity increases Aldo Leopold said that we know very little of the ecological roles of the world’s species. Until we know more we should use the precautionary principle.

4. Carboniferous Cretaceous Devonian Jurassic Silurian Triassic Tertiary Ordovician Permian Quaternary Cambrian 408 245 2 Geological Periods Mass extinctions 800 600 Number of families of marine animals ? 400 200 0 570 505 438 360 286 208 144 65 0 Millions of years ago Fig. 22.10, p. 558

5. The extinction crisis Many scientists believe there is ample evidence to show that we are in the middle of the six mass extinction. • WWF found that 34%fish, 25%amphibians, 24%mammals, 20%reptiles, 14% plants, 12%birds are under threat of extinction • 11,046 plant and animal species are at risk of becoming extinct. • In the US 539 species have become extinct and 33% are threatened • At a 1% extinction rate 1/5 of the species will be gone by 2030 • Many scientists believe it is higher than this

6. Arctic Circle Arctic Circle 60° EUROPE NORTH AMERICA ASIA 30°N Tropic Of Cancer Atlantic Ocean AFRICA Pacific Ocean Pacific Ocean 0° 150° 120° 90° 30°W 0° 60°E 90° 150° SOUTH AMERICA Indian Ocean Tropic Of Capricorn AUSTRALIA 30°S Antarctic Circle 60° ANTARCTICA Critical and endangered Threatened Stable or intact Projected Status of Biodiversity 1998–2018 Fig. 22.3, p. 552

7. There are three main things that may make the extinction even worse. • We are destroying, simplifying and degrading coral reefs, tropical forests, wetlands and estuaries that have in the pass served as important centers for the recovery of biodiversity after mass extinction and reducing the rates of speciation • This is the fastest that it has ever happened in history • Human population will accelerate losses.

8. The difficulty in estimating the extinction rate • 1. extinction takes a long time and is difficult to estimate • 2. scientists have only identified 1.4 million species of the world’s 4 to 100 million • 3. scientists know little of the species they are trying to document. • The RED LIST: 16,000 species at risk of extinction compiled by World Conservation Union

9. Characteristic Examples Low reproductive rate (K-strategist) Blue whale, giant panda, rhinoceros Specialized niche Blue whale, giant panda, Everglades kite Narrow distribution Many island species, elephant seal, desert pupfish Bengal tiger, bald eagle, grizzly bear Feeds at high trophic level Fixed migratory patterns Blue whale, whooping crane, sea turtles Rare Many island species, African violet, some orchids Commercially valuable Snow leopard, tiger, elephant, rhinoceros, rare plants and birds Large territories California condor, grizzly bear, Florida panther Fig. 22.8, p. 558

10. Threatened vs. Endangered: • Threatened means that it is still abundant, but the numbers are rapidly declining and it is likely to become endangered. • Endangered: when there are so few animals that the species could become extinct over most of its range.

11. Florida manatee Northern spotted owl (threatened) Gray wolf Florida panther Bannerman's turaco (Africa) Devil's Hole pupfish Snow leopard (Central Asia) Black footed ferret Symphonia (Madagascar) Utah prairie dog (threatened) Fig. 22.7a, p. 556 Ghost bat (Australia) California condor Black lace cactus Black rhinoceros (Africa) Oahu tree snail

12. Grizzly bear (threatened) Arabian oryx (Middle East) White top pitcher plant Kirtland's warblers African elephant (Africa) Mojave desert tortoise (threatened) Swallowtail butterfly Humpback chub Golden lion tamarin (Brazil) Siberian tiger (Siberia) Fig. 22.7b, p. 557

13. West Virginia spring salamander Giant panda (China) Knowlton cactus Whooping crane Blue whale Mountain gorilla (Africa) Swamp pink Hawksbill sea turtle El Segundo blue butterfly Pine barrens tree-frog (male) Fig. 22.7c, p. 557

14. Critical population density (minimum viable population size): critical size of a population below which reproduction does not take place. Even though the this species is not extinct its numbers will continue to decline

15. Why preserve wild species • Economic and medical importance • 90% of today’s food crops were domesticated from wild plants • Genetic engineers require existing wild species as sources of genetic material to develop new crop strains • They supply lumber, dyes, paper, fuel, fiber, oils, rubber • 40% of all medicines (worth 200 billion dollars per year) were derived from living organisms that mainly come from the rainforests

16. Scientific and Ecological importance of Wild Species • Every species can help scientists understand how life evolved and functions • Produce oxygen, absorb pollutants, moderate climate, recycle nutrients, store solar energy, detoxify toxins, natural pest control • Provide genes for future evolution

17. Aesthetic and Recreational Importance of Wildlife • Biophelia: love of nature • A source of beauty, wonder, joy and recreational pleasure • Americans spend $18.2 billion per year on ecotourism • Save them because Mrs. Sealy likes them

18. It is Ethically important to preserve wild species • Each species has a right to exist unrelated to its usefulness to us • It is ethically wrong for us to hasten the extinction of any species, and we have the ethical responsibility to protect species from premature extinction.

19. Causes of premature Extinction • 1. Underlying Causes - population growth - Economic systems that fail to value the ecological services - High per capita resource use.

20. Causes of Premature Extinction • HIPPO • H: habitat degradation and fragmentation • I: invasive species • P: pollution • P: population of humans increasing • O: overharvesting and poaching

21. Direct causes • Habitat Loss and Fragmentation: • In order of decreasing impact: worst: rainforests, coral reefs, wetlands, grasslands, pollution of freshwater. • Habitat fragmentation (1st) increases exposed surface area making animals more vulnerable to predator, disease, etc. (2nd) patches are to small to support viable populations (3rd) creates barriers that limit species ability to colonize new areas. The map shows important Aspen stands (shown in red), the open Birch (with some Aspen) wood mix (shown in orange) and commercial conifer woodlands. The commercial conifer woodland at Balliefurth forms an effective barrier and block to Aspen species dispersal and movements in Strathspey.

22. . Direct causes • Commercial Hunting and Poaching: Illegal sale of species, $12 billion per year organized crime has been getting involved in smuggling • Bushmeat: hunting wild animals for food is depleting many of the great apes and monkeys

23. . Direct causes • Over fishing: Only large fish are caught-all other animals are thrown back dead or dieing (overcatch)- drift-net fishing is the worst, everything that touches this “invisible curtain of death” dies

24. . Direct causes • Predator and Pest Control: People exterminate species that compete for food and game animals. Wolves, prairie dogs, parakeets, elephants, coyotes.

25. . Direct causes • Market for exotic Pets and decorative Plants: For every live animal captured and sold 50 others are killed. Birds, amphibians, mammals, reptiles and tropical fish, exotic plants like cacti and

26. . Direct causes • Climate Change and Pollution: Global warming and toxic chemicals

27. . Direct causes • Non-Native Species: Can be accidental or deliberate, some have no natural predators, competitors or parasites so they take over the ecosystem and crowd out other species called native species

28. Stopping Invasive Species • 1. do not allow wild animals to escape • 2. Inspect imported goods • 3. Ships replace ballast water with fresh seawater before entering ports • 4. Do not trade plants or animals from overseas • 5. Do not dump your aquarium into local waterways • 6. Clean your recreational gear before heading home, such as boots, kayaks, mountain bikes, dive gear etc.

29. Habitat loss Habitat degradation Overfishing Basic Causes Introducing nonnative species Climate change • Population growth • Rising resource use • No environmental accounting • Poverty Commercial hunting and poaching Pollution Sale of exotic pets and decorative plants Predator and pest control Fig. 22.13, p. 564

30. III. Approaches to Protecting Species Against Extinction • Ecosystem approach: legally protect wilderness areas • Species approach: protecting endangered species by identifying them and giving them legal protection • Wildlife management approach: manage game species for sustainable yield. Using hunting laws, harvest quotas etc.

31. The Species Approach The Ecosystem Approach Goal Goal Protect populations of species in their natural habitats Protect species from premature extinction Strategies Strategy • Identify endangered species • Protect their critical habitats Preserve sufficient areas of habitats in different biomes and aquatic systems Tactics Tactics • Protect habitat areas through private purchase or government action • Eliminate or reduce populations of alien species from protected areas • Manage protected areas to sustain native species • Restore degraded ecosystems • Legally protect endangered species • Manage habitat • Propagate endangered species in captivity • Reintroduce species into suitable habitats Fig. 22.5, p. 555

32. Use Treaties: • 1975 Convention on International Trade in Endangered Species (CITES). Signed by 169 countries. Lists 900 species that cannot be commercially traded as live specimens or wildlife products because they are in danger of extinction. It also lists 28,000 species whose international trade is monitored and regulated because they are at risk of becoming threatened. Problems: enforcement is difficult and spotty, convicted violators often pay only small fines, member countries can exempt themselves from protecting any species that is on the list, much of the highly profitable trade of these animals goes on in countries that have not signed the treaty.

33. Treaties • The Convention on Biological Diversity: Signed during the 1992 Rio Earth Summit. Ratified by 188 countries. The US has refused to ratify this treaty, which has hindered progress. Countries commit to preserving wild species

34. Use Laws • Endangered Species Act: (1973, 2006) makes it illegal for Americans to trade, kill or use any product from an endangered species. (Unless for scientific purpose or enhance the survival of the species. Currently the list has over 1,260 species (60% animals 40% plants) • Also makes it illegal for state or federal governments to authorize any project that will jeopardize an endangered species. • 1,260 on the list, 50-85 added every year • Fish and Wildlife and National Marine Fisheries put together the list • All species that are listed are required to have a “critical habitat” needed for its survival and recovery – only ¼ currently have a plan

35. Bad Politics • In 1996 this act was almost replaced by U.S Congress who were being backed by timber, mining, and private industry. • Tried to make wildlife protection voluntary on private land • Attempted to have government pay landowners if their land was unusable in order to protect an endangered species – regulatory taking • Make it harder and more expensive to list newly endangered species by tying up government wildlife officials in hearings and pre-review panels • Allowing secretary of the interior the power to allow a listed species to become extinct -God Squad • give landowners exemptions from the law, and prohibiting the public from commenting or filing lawsuits to change poorly designed habitat conservation plans. “HCPs”

36. ***Opponents say ESA has been unsuccessful because only a few species have been removed from the list. However, many populations have stabilized – 40%

37. Strengthen the ESA • Find out what ecosystems we have. • Protect most endangered ecosystems. • Offer financial incentives to private landowners to protect species. • Operates on very limited funds. So we need to decide which species to save. Environmentalists want the following considered: • Have the best chance for survival. • Have the most ecological importance to the ecosystem. • Potentially useful for agriculture, medicine or industry. • Some say we don’t have enough info to make these decisions.

38. Encouraging Private Landowners to Protect Species • Use Habitat Conservation plans which allow landowners to kill a certain number of endangered species in exchange for protecting species. This could include setting aside part of the species habitat as a preserve, paying to relocate the species, paying the government money to set up a suitable habitat elsewhere. • safe Harbor agreements- voluntary agreement to maintain habitat in exchange for technical assistance and assurances of no further future restrictions • candidate conservation agreements – agree to save species not yet listed in exchange for govt subsidies

39. Conservation • Conservation Easements: The Nature Conservancy has preserved 10,800 square miles by buying the land.

40. Wildlife Refuges: 508 refuges, 20% endangered species inhabit them.

41. Gene Banks & Botanical Gardens: storing seeds under refrigeration. Expensive, doesn’t work with all seeds, to little storage capacity.

42. Zoos • Zoos: focus on large charismatic animals; rely on egg pulling & captive breeding. Most reintroductions fail. Lack of space & money cant support the minimum # of animals needed to sustain the pop.

43. Wildlife Management • 1.Manipulation of wildlife populations for their welfare & human benefit. • 2. 90% is devoted to producing surpluses of game animals & game birds. • 3.Wildlife manages the growth of plant species that are the best cover & food for game animals. • 4. Sport hunting: sport-hunting laws to manage populations of game animals- like limits on age, sex, number, etc. Proponents of hunting claim we need to keep down the # of deer because there is a population explosion. Opponents say a surplus is deliberately created and that the deer is used as a smoke screen to hunt many other animals. • Management of Migratory Waterfowl: ducks, geese, song –birds that fly in north-south routes called flyways. International Treaties to protect habitats, regulate hunting Bonn Germany