Links for Enrichment and Further Learning

• WildCam Africa: Live web cam of Pete's pond in Botswana
• World Atlas of Biodiversity
• United Nations Environment Programme - Forests
• World Database on Protected Areas
• California: Invasive, nuisance and exotic species
• Non-native red fox in California
• California Native Plant Society: Exotics
• Biodiversity and Conservation: A Hypertext Book by Peter J. Bryant
• Endangered species program - US Fish and Wildlife Service
• California's threatened and endangered species
• Bald Eagle reintroduction on Catalina Island

Student Learning Outcomes. Following successful completion of this lesson, students should be able to:

Study Questions / Quiz Prep. (Consult Required Reading and lecture notes for answers.)

1. Evidence in the rocks indicates that Earth has experienced several, previous mass extinction events. How is the current mass extinction event different from those of the past?
2. In the recent past, and in some cases today, over hunting has caused the extinction of animals such as the saber-toothed cat, wooly mammoth, Stellar's sea cow, New England sea mink and the dodo bird of Mauritius Island. But today, what is the main cause for species extinctions?
3. On the map below, label the top ten countries in terms of total area of forest cleared in the period between 1990-2000. (You may consult to following link for a world map: http://en.wikipedia.org/wiki/World_map .

4. Geographically, what is the notable relationship between these top ten countries and the planetary region of greatest biodiversity?
5. About how many square kilometers of tropical rain forest are being destroyed every year.
6. Using the following links, the area of which state in the the USA most closely matches the area of annual tropical rain forest destruction?

• http://en.wikipedia.org/wiki/New_jersey  (New Jersey)
• http://en.wikipedia.org/wiki/Louisiana (Louisiana)
• http://en.wikipedia.org/wiki/California (California)
• http://en.wikipedia.org/wiki/New_york (New York)

7. On the map above, label Madagascar.
8. How much of the original forest remains on the island of Madagascar?
9. Identify one type of animal at risk of extinction on Madagascar.
10. On the map above, label Borneo.
11. Identify one type of animal at risk of extinction on Borneo.
12. On the map above, label Kenya.
13. Identify one type of animal at risk of extinction in Kenya and eastern Africa.
14. Identify one type of animal at risk of extinction in Central America and South America.
15. On the map above, label southern California.
16. Identify one type of animal at risk of extinction in southern California.
17. What are the main reasons that humans destroy natural habitat?
18. Salt cedar is a plant that was recently introduced by humans to the southwest USA for a variety of reasons. It has since spread out and now dominates patches of many natural habitats. Be able to identity a photograph of salt cedar.
19. How does salt cedar become a problem to native plants?
20. How does salt cedar cause problems for the desert pupfish?
21. The brown tree snake was introduced to the islands of Guam and Hawaii. How did this snake cause problems to the native animals?
22. Pampas grass seems pretty enough. Why is this introduced plant problematic to the native plants of California?
23. Sweet fennel and black mustard have been introduced to California. How do these plants cause problems to the native ecosystems they invade?
24. What is an endemic species?
25. The International Union for the Conservation of Nature has developed a classification scheme for species based on their probability of extinction. List and define the three levels in this scheme.
26. Refer to Table 28.2. In terms of the number of threatened species as a percentage of the number of evaluated species, which groups are at greatest risk from each of the following categories: 1) vertebrates; 2) invertebrates; 3) plants?
27. Conservationists realize that they do not have sufficient time and resources to save all threatened species on the planet. How then do they recognize and define the most important areas to which they should devote their limited time and resources?
28. What are the three characteristics of a biodiversity hotspot?
29. Is there a biodiversity hotspot in California?
30. Define: minimum viable population.
31. How would the minimum viable population size differ between the two following groups: 1) invertebrates and annual plants; 2) vertebrate species?
32. Define: minimum dynamic area.
33. Refer to figure 28.14. According to this graph, how many large carnivores could a park with an area of 10⁴ hectares support?
34. Refer to figure 28.14. According to this graph, if we want to create a park only for populations of 1000 small herbivores, how many hectares should our park be?
35. J. Berger studied 120 populations of free-ranging bighorn sheep in the American southwest. According to this investigation, what is the minimum viable population for this species?
36. Conservationists have had differential success relocating and reintroducing black rhinos and white rhinos in Africa. Why so different?
37. Before California Condors could be reintroduced to the wild, their total numbers had to be increased. How did conservationists successfully increase the condor populations?
38. After being regionally extinct for decades, the gray wolf has been reintroduced to Yellowstone National Park. What were the immediate changes that the wolves caused to the Yellowstone ecosystem?
39. The American bald eagle recently was reintroduced to Catalina Island off the coast of southern California. How can these large predatory birds possibly find enough food to eat while living on this small island?
40. Below are two pictures that represent the geographic arrangements of two protected areas. Protected land is shown in black. Both areas are equal in size. Which is better?

(a)

(b)

41. In the USA, where are most of the protected lands?
42. In the USA, what is the main geographic characteristic shared by most regions of protected lands?
43. What are the three arguments presented by conservationists for the maintenance of biodiversity?

Synthesis (These are not official study questions. But you should try to answer them on your own.)

Presentation

Biodiversity

A map showing that the tropical zone has the greatest number of species on the planet.

Habitat Loss

Image source: United Nations.
Global distribution of original and remaining forests

Images source: Pearson Education, Inc.
History of habitat loss in Madagascar.

Image source: Google maps.
A close up view of habitat destruction in Madagascar. The pattern shown here indicates: 1) clear-cutting the rain forest in order to harvest timber; and 2) conversion of rain forest to pasture land to support grazing cattle.

Images source: Unknown.
Lemurs at risk of extinction in Madagascar.

Image source: Google Earth.
Deforestation in Borneo. As in Madagascar, deforestation progresses as a wave of destruction moving from the coasts toward the interior.

Image source: Unknown.
Orangutans are at risk of extinction on Borneo.

Image source: Google Earth.
Deforestation in Kenya surrounds islands of protected lands.

Image source: Unknown.
Mountain gorillas are at risk of extinction in eastern Africa.

Image source: Pearson Education, Inc.
Deforestation in Rondonia, Brazil.

Image source: Google Earth.
Deforestation in Rondonia, Brazil.

Image source: Unknown.
Jaguars are at risk of extinction in Central America and South America.

Image source: Google Earth.
Deforestation in Weakley County, Tennessee, USA.

Images source: Unknown.
Grizzly bear (left) and the gray wolf (right) now are regionally extinct in nearly all of their former ranges in North America.

Image source: Google Earth.
Deforestation in Orange County, CA, USA. Endangered Coastal Sage Scrub habitat inconveniently occupies the most buildable land in Southern California.

Image source: Unknown.
California gnatcatcher at risk of extinction in Southern California.

Image source: Unknown.
A truck carries a load of trees removed from a natural forest. The trees will be used for lumber, paper or fiiber.

Images source: Unknown.
Products directly produced from harvested trees.

Image source: Unknown.
Cattle graze on pastureland made available after clearing away the original forest.

Images source: Unknown.
Products directly produced from cattle.

Image source: Unknown.
Harvesters collect a crop of wheat in an enormous wheat field. The farmland was made available after clearing away the original woodland or natural prairie communities.

Images source: Unknown.
Products directly produced from harvested fields of grain.

Introduction of Alien Species

California

Plants

Images source: Unknown.
Salt cedar (above left) is an aggressive plant that crowds out native plants. Salt cedars are exceptionally active ground water pumps. In large stands, they can rapidly deplete ground water reserves and cause ground water levels to drop. This can cause water levels in desert ponds to drop or disappear altogether. Many desert animals depend on desert ponds for water, such as the endangered desert pupfish (above right), local rodents, migratory birds and insects. The draining of these ponds by salt cedar results in fatal consequences to numerous species of desert animals.

Finally, salt cedar "leaves" secrete large amounts of salt. The salt falls to the ground and accumulates, making the soil too salty for other plants.

Image source: Unknown.
Pampas grass. Pampas grass is an aggressive plant that can rapidly colonize and dominate any suitable territory. Pampas grass seeds are carried by the wind, helping the species to rapidly spread downwind. When it does, the diverse, native flora can be quickly replaced by a monoculture of pampas grass.

Image source: Unknown.
Sweet fennel. Sweet fennel is an aggressive plant that tends to dominate its territory, crowding out native plants and transforming a diverse ecosystem into a monoculture.

Image source: Unknown.
Black mustard. Black mustard spreads rapidly and dominates new territories. Its success crowds out native plants, resulting in a loss of biological diversity.

Animals

Images source: Unknown.
Red fox (left), San Joaquin kit fox (right). The red fox is a larger, stronger and more aggressive fox when compared to the San Joaquin kit fox. As a result, the introduction of the red fox has caused native kit fox populations to decline.

Images source: Unknown.
German brown trout (left), Golden trout (right). Fishermen periodically (and illegally) introduce German brown trout into high Sierra lakes. The brown trout out competes and devours the native golden trout.

Threatened and Endangered Species

Image source: Pearson Education, Inc.
Table of threatened and endangered species. Click here for larger view.

Image source: Pearson Education, Inc.
Biodiversity hotspots. Places around the world where there is: 1) high species diversity; 2) high species endemism; 3) large impact from human activities.

Minimum Viable Populations (MVP) and Minimum Dynamic Area (MDA)

Image source: Pearson Education, Inc.
This graph indicates that for any given minimum viable population size, large carnivores require the greatest amount of territory. NOTE: a hectare is 10,000 square meters (2.47 acres), about the size of two and a half football fields.

Images source: Pearson Education, Inc.
Bighorn sheep of the southwest USA (left). At right, the results of a study of 120 populations of bighorn sheep in the American southwest by J. Berger. Results indicate that populations of bighorn sheep of less than 100 tend to go extinct quickly. Populations of 100 or more tend to persist.

Reintroduction

Image source: Pearson Education, Inc.
A black rhinoceros is released into a protected area in South Africa.

Image source: Pearson Education, Inc.
Range history of the black rhinoceros. Note that this once free-ranging species is now restricted to isolated protected areas.

Image source: Pearson Education, Inc.
Feeding a California Condor chick using a surrogate puppet. The puppet is used so that the chick "imprints" on condors and not humans. The person operating the puppet is hidden from the chick with curtains.

Image source: Pearson Education, Inc.
Wildlife biologists release a juvenile condor into a controlled compound in preparation for final release to the wild. This condor was raised in captivity in order to better protect young condors and safeguard against critical losses.

Images source: Unknown.
A map showing the location of Yellowstone National Park. Regionally extinct for decades, the gray wolf was reintroduced to Yellowstone in 1995. Since then the gray wolf population has rapidly increased.

Images source: Unknown.
On Santa Catalina Island, a wildlife biologist feeds a bald eagle chick with a puppet. Bald eagles were reintroduced to the island in 1980. Bald eagles are fish predators and soar above the island's coastal waters in search of fish. They are experts at using their large talons to snatch up fish swimming just under the surface.

Habitat Protection

Image source: Pearson Education, Inc.
Current estimates of the percentage of land now protected from the destructive actions of humans.

Image source: Pearson Education, Inc.
Maps showing the patterns of protected lands in the USA.