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Unit 2 Lesson 8: - Biodiversity Hotspots - Brown Bag Surprise Activity - Problems associated with biodiversity - Habitat fragmentation.

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Presentation on theme: "Unit 2 Lesson 8: - Biodiversity Hotspots - Brown Bag Surprise Activity - Problems associated with biodiversity - Habitat fragmentation."— Presentation transcript:

1 Unit 2 Lesson 8: - Biodiversity Hotspots - Brown Bag Surprise Activity - Problems associated with biodiversity - Habitat fragmentation

2 What Are Species? Species definitions:
Reproductive isolation - organisms that breed in nature and produce fertile offspring Phylogenetic species concept - emphasizes the cladistic relationships (branches on a taxonomic tree) Evolutionary species concept – defines species in terms of evolutionary history

3 Keystone Species Sometimes the loss of one species from a community can have a disproportionately large effect on the entire community. Keystone species play a role in its community that is far more important than its relative abundance might suggest. Typically exist in low numbers Could be predators, sources of food, mutualistic species or providers of other essential services

4 Keystone Predator example (aka Predator-Mediated Competition)
Keystone predators.  Sea stars are keystone predators in their rocky intertidal communities in Washington State. When sea stars are present, they consume mussels, which are strong competitors for space. This predation creates open spaces that inferior competitors can colonize. As a result, the diversity of species is high. In the absence of sea stars, the mussels dominate the surfaces of the intertidal rocks, and the diversity of species declines dramatically.

5 Other examples of Keystone Species
A species that provides food for a community at times when food is scarce  Ex. plants that produce nectar and fruits (make up less than 1% of the plant diversity in the tropical forests of Central & South America) During a 3-month period when food is scarce for herbivores, they rely on the less abundant fruits and nectar for food, making those plants keystone species in that community

6 Other examples of Keystone Species
A species that is important because of its mutualistic interactions with other species  Ex. rare pollinator species in some communities, such as the flying fox bat found on South Pacific islands. It is the only pollinator and seed disperser for hundreds of tropical plant species. Unfortunately the flying foxes have been hunted for food to near extinction.

7 Other examples of Keystone Species
A species that maintains habitats for other species (ecosystem engineers) Ex. North American beaver only makes up a small percentage of the total biomass of the North American forest, but the dams they build convert narrow streams into large ponds, thereby creating new habitats for pond-adapted plants and animals.

8 How Many Species Are There?
1.2 million species are catalogued. Latest biodiversity estimate: 8.7 million eukaryotic species (+/- 1.3 million) Invertebrates make up 76% of all known species, and probably most of yet to be discovered species. Tropical rainforests and coral reefs are biodiversity hotspots. 34 hotspots (1.4% of world’s land area) contain 75% of the world’s most threatened mammals, birds and amphibians. Current number from

9 Biodiversity Hotspots

10 Benefits of Biodiversity
Food Wild plants could provide new sources of food or more genetic diversity for existing crops. Drugs and Medicines More than half of all prescriptions contain some natural product. Pharmaceutical companies actively prospect tropical countries for products. Resources often extracted without compensation (biopiracy). Sharing profits provides an incentive to preserve native species.

11 Benefits of Biodiversity
Ecological Benefits Soil formation, waste disposal, air and water purification, nutrient cycling, solar energy absorption, and biogeochemical and hydrological cycles all depend on biodiversity. We do not fully understand biological communities. Loss of a seemingly insignificant species can be damaging.

12 Benefits of Biodiversity
Aesthetic and Cultural Benefits Hunting, fishing, camping, hiking, etc. USFWS estimates Americans spend $104 billion annually on wildlife-related recreation. Ecotourism can be an important form of sustainable economic development. Existence (intrinsic) value - organisms have value in and of themselves.

13 Lesson 7: So can you…? I can identify characteristics of endangered and invasive species. I can explain the difference between r-selected and K-selected species Explain the importance of a keystone species I can explain what biodiversity means and the different types of biodiversity that exist.

14 Lesson 8: Today’s Learning Targets
I can explain what biodiversity means and the different types of biodiversity that exist. I can identify threats to biodiversity I can identify events that can lead to extinction I can discuss legislation that exists to prevent reductions in biodiversity I can discuss the case study on two recovery efforts

15 Brown Bag Surprise Activity Calculating Species Richness

16 Interpreting Scientific Data
Palau Island (north of Australia) Norfolk Island Seychelles Island Patagonia Galapagos Island Palau Island (north of Australia) Norfolk Island (east of Australia) Seychelles Island Patagonia (shared area of Argentina & Chile)

17 Threats to Biodiversity
Extinction - elimination of a species Natural Causes In undisturbed ecosystems, background rate appears to be one species per decade. In this century, human impacts have accelerated that rate, causing perhaps hundreds to thousands of extinctions annually.

18 Natural Extinction Fossil record suggests more than 99% of all species ever in existence are now extinct. Periodically, the Earth has experienced 5 mass extinctions. Permian period - 95% of marine species and nearly half of all plant and animal families died out 250 million years ago. End of Cretaceous - Dinosaurs and 50% of existing genera disappeared 65 million years ago.

19 What are some man-made impacts that have caused reductions in biodiversity?

20 Accelerating Extinction Rates
Humans are accelerating the natural extinction rates by 100x to 1000x. If present trends continue, between 22% and 47% of all plants species will become extinct within 50 years. Animals dependent upon them would also become extinct. This is equivalent to other mass extinctions like the Cretaceous extinction.

21 Human-Caused Reductions in Biodiversity
Acronym HIPPO summarizes the issues: Habitat destruction Invasive species Pollution Population Overharvesting 2:43 video clip from PBS on biodiversity:

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23 Habitat Fragmentation

24 Human-Caused Reductions in Biodiversity
Habitat Destruction Habitat loss = greatest cause of extinction Conversion of forest to farmland, cities, etc. Only 1/5 of remaining forest is old growth. Loss of habitat due to mining, dams, destructive fishing practices Habitat is fragmented into small, scattered plots

25 Habitat Fragmentation

26 Human-Caused Reductions in Biodiversity
Habitat Destruction – Desertification In semiarid environments, dry, nutrient-poor soil can be easily degraded by agriculture to the point at which it is no longer viable for any production at all. Irrigation can cause salinization, and topsoil is eroded away because of the shallow roots of annual crops failing to hold it in lace

27 Desertification

28 Human-Caused Reductions in Biodiversity
Invasive Species Invasive (exotic) organisms thrive in new territory where they are free of usual predators, diseases, or resource limitations that limited them in original habitat. Over past 300 years, approximately 50,000 non-native species have become established in the U.S. At least 4,500 are free-living. 15% cause environmental damage.

29 Human-Caused Reductions in Biodiversity
Commercial Products and Live Specimens Wildlife smuggling is very profitable. Fur, horns, live specimens, folk medicine Leopard fur coat = $100,000 Mature cactus = $1,000 5 million wild birds sold worldwide each year Additional 3 million caught but die before reaching market 128 million tropical fish sold annually in U.S.

30 Human-Caused Reductions in Biodiversity
Bush meat market - more than 1 million tons of wild animals are sold for human food annually. Cyanide fishing is killing reefs in the Philippines and Indonesia. Cyanide released above coral reefs to stun fish. A single diver can kill all life on 200 sq. meters of coral reef in one day.

31 Human Causes to Reductions in Biodiversity - Pollution
Eutrophication A body of water’s increase in fertility due to anthropogenic inputs of nutrients. Increase algae (bloom) Algae dies; microbes digest algae, consuming O2 Lack of O2 creates “dead zones”

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33 What legislation exists to prevent future reductions in biodiversity?

34 Endangered Species Act

35 Endangered Species Act
Established in 1973 Endangered are those considered in imminent danger of extinction. Threatened are those likely to become endangered, at least locally, in the near future. Vulnerable are those that are naturally rare or have been locally depleted to a level that puts them at risk.

36 Endangered Species Act Prohibits…

37 Endangered Species Act
ESA regulates a wide range of activities involving endangered species: Taking (harassing, harming, pursuing, hunting, shooting, killing, capturing, or collecting) either accidentally, or on purpose Selling Importing into or Exporting out of the U.S. Possessing Transporting or Shipping Prohibitions apply to whole organisms, body parts, and products made from the organisms.

38 Endangered Species Act
Currently, U.S. has 1,165 species on its Endangered list, 326 Threatened lists, with more candidate species waiting for consideration. Number reflects more about human interests than actual status Invertebrates make up 75% of all species, but only 18% of T/E list. Listing process is extremely slow; at least 18 species have gone extinct since being nominated for protection. Only 593 active recovery plans right now Insects 2013 = 208 species / 1165 = 18%  As of2004, the CBD counted 85 species that had gone extinct before they were ever placed on the list at all. More have died off since then.

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40 Reauthorizing ESA Endangered Species Act officially expired in 1992.
Farmers, loggers, miners, ranchers, developers have tried to prevent its reauthorization. Scientists think we should focus on continent-wide preservation of ecosystems that support maximum biodiversity rather than individual species. Gap analysis - seeks out unprotected landscapes rich in species

41 Recovery Plans

42 Recovery Plans Once a species is endangered, USFWS is required to propose a recovery plan detailing the rebuilding of the species to sustainable levels. Takes years, is expensive, and is subject to political interference Once a species is endangered, much of its habitat and ability to survive is often compromised.

43 Recovery Plans Some endangered species merit special attention. Keystone species - species has major effect on other members of community Indicator species - tied to specific communities or successional stages Notable successes include bald eagle, alligator, whooping crane Indicator species – a species that indicates health of living conditions within the habitat. Ex. +/- disease-causing pathogens present; health of other organisms lower on food chain Indicator species – - Opossum - Southern Flying Squirrel - Red Bellied Woodpecker - Carolina Wren - Eastern Hognose Snake - River Otters - Eastern Spiny Softshell Turtle , Lichen - Tulip Tree - Sassafras - Red Cedar - White Oak- Spicebush - Prickly Ash - Buttonbush

44 Recovery Plans Umbrella species - require large blocks of undisturbed habitat Flagship species - attractive organisms to which people react emotionally (Panda) Notable successes include bald eagle, alligator, whooping crane Umbrella Species: Northern spotted owls and old growth forest : ex. Molluscs and salamanders are within the protective boundaries of the northern spotted owl. The flagship species concept holds that by raising the profile of a particular species, it can successfully leverage more support for biodiversity conservation at large in a particular context.

45 Captive Breeding Breeding programs in zoos and botanical gardens are one method of saving threatened species. Repositories of genetic diversity Most mammals in North American zoos are now produced from captive-breeding programs. Reintroduction programs But many species do not reproduce in captivity, and there are not enough zoos to maintain every species. Lynx, African raptor,

46 Neem of Hawaii Restored by Captive Breeding
Captive Breeding Success Story!

47 Black-Footed Ferret of the Western Plains Restored by Captive Breeding
Captive Breeding Success Story!

48 Captive Breeding Issues
Can you think of some issues associated with captive breeding? Zoos have limited space How many can/should we save? Should we preserve pathogens? Parasites? Continued inbreeding of zoo specimens may lead to fertility and infant survival problems. Natural habitat may disappear while we are busy conserving the species itself. Another alternative is to attempt to save species in the wild. Provide funding for protection in native habitats

49 American Whooping Crane and the California Condor
Case Study American Whooping Crane and the California Condor Read the case study then identify the main points American Whooping Crane California Condor

50 Lesson 8: So can you…? I can explain what biodiversity means and the different types of biodiversity that exist. I can identify threats to biodiversity I can identify events that can lead to extinction I can discuss legislation that exists to prevent reductions in biodiversity I can discuss the case study on two recovery efforts

51 Hidden slides follow

52 Nitrogen Cycle Denitrification is a biochemical pathway in which anaerobic bacteria are able to use nitrate (NO3) in their respiration instead of oxygen and as product nitrogen gas (N2) is released back to the atmosphere. This information is usually presented with the nitrogen cycle. 2 NO3 + 10e- + 12H2 + → N2 + 6 H2O -Ammonification is a bacterial pathway decomposes organic nitrogen to NH4 + or NH3. The source of the nitrogen may come from nucleic acids (DNA and RNA) or proteins -Excretion is the process of animals eliminating nitrogenous wastes -Assimilation in biology is the conversion of absorbed food into substance of the body. Example absorbing amino acids and assimilating them into proteins like hemoglobin for the body. -Nitrogen fixation is he biochemical pathway of converting nitrogen gas (N2) into the more usable form of ammonia (NH3). N2 + 6 H -> 2NH3

53 Endangered Species Management
Hunting and Fishing Laws By 1890’s, most states had enacted some hunting and fishing laws. General idea was pragmatic, not aesthetic or moral preservation. In general, regulations have been extremely successful. White tailed deer Wild turkey Snowy egret

54 Recovery Plans Opponents have continually tried to require economic costs and benefits be incorporated into planning. In 1978, construction of Tellico Dam in Tennessee threatened a fish called the snail darter. A federal committee was given the power to override the ESA for economic reasons. Sometimes economic interests are in conflict. Commercial and sport fishing for salmon in Columbia River is worth 1 billion per year, but farmers and electric utilities want the dams that provide irrigation and hydroelectric power.

55 Private Land and Critical Habitat
Eighty percent of habitat for more than half of all listed species is on non-public property. Supreme Court has ruled destroying habitat equates to taking. USFWS has been negotiating Habitat Conservation Plans (HCP) with private landowners. Landowners allowed to harvest resources or build on part of land as long as endangered species benefits

56 Gap Analysis This biodiversity map of the island of Hawaii shows areas of high species richness that are not protected in any preserve and preserves that have scenic and recreational value, but little in the way of species protection.

57 Habitat Protection Grumbine suggests 4 principles:
Protect enough habitat for all native species in a given region Manage at regional scale large enough to accommodate natural disturbances Plan over a period of centuries Allow for human use at a level that does not result in significant ecological degradation

58 International Wildlife Treaties
Convention on International Trade In Endangered Species (CITES) Regulates trade in living specimens and products derived from listed species Currently lists 700 species threatened with extinction by international trade


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