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1 QUIZ 2

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3 FINAL EXAM 2a 3

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10 FINAL EXAM 29 Question. Define biodiversity. Anything along these lines is okay:..the sum total of all living things the immense richness and variation of the living world. or The numbers and relative equitability of different biological variants found in a given place and time Question 2. Describe one important weakness of the Canadian Species At Risk Act with respect to its effectiveness in protecting biodiversity. Explain your answer. Any of the following (others possible): - only applies to federal land (which makes up small portion of country) - protects listed species and their residences but not really their habitats, except on federal land - species may be excluded if their protection has negative economic or social impacts

11 Question 3. In terms of the overall goal of protecting biodiversity, provide one possible benefit and one possible risk of using assisted colonization as a management tool. Benefit (2.5 marks) - Help species avert extinction - Help maintain species abundance/adaptation - Help maintain ecosystem services Risks (2.5 marks) - Create an invasive population - Hybridization = creation of invasive, swamping/assimilation - Reduce genetic differentiation of populations Question 4. For a population of grizzly bears, demographic data were collected over a period of four years, allowing three year-to-year estimates of the population growth rate (λ) to be calculated: λ =., λ 2 =.5, λ 3 =.7. Over the long term, do you expect this population to grow, shrink, or remain at approximately the same size? Explain your answer. Population should shrink (3 marks) because. x.5 x.7 < (2 marks) Question 5. Tomatoes (Solanum lycopersicum) originated in South America, and prior to the age of European exploration tomatoes grew only in South America. Tomatoes are now grown by people in many parts of the world, including the Vancouver area. In the Vancouver area, would you consider tomatoes to be a native species? Explain your answer. No. (2 marks) Species are native where they occur naturally (i.e., without human assistance) (3 marks) Question 6. In the Vancouver area, would you consider Solanum lycopersicum to be invasive? Explain your answer. No (2 marks) Invasive species are those that humans perceive as a problem, and tomatoes are not a problem (3 marks)

12 Question 7. The graph to the right shows the survival rate (mean ± SE) for adult sea turtles either in areas of the ocean where Turtle Exclusion Devices (TEDs) have been used since 22, or in areas of the ocean where TEDs have not been used (Control). TEDs allow turtles to escape from fishing nets. According to these data, have TEDs been an effective conservation tool? Explain your answer. Survival rate TEDs used Control Year Yes (2 marks) Relative to control areas, areas where TEDs were used show improved survival (3 marks) Question 8 List and explain three different reasons you may want to conserve biodiversity. Any 3 of the following: - Biodiversity/Species have inherent value - Biodiversity provides goods to people: food, fiber, medicine - Biodiversity provides services to people: water purification, flood control, etc. - Biodiversity has information value for scientific research - Biodiversity has psycho-spiritual/aesthetic value for people (it makes us happy) Listing two or more things within one of these categories is okay too 2

13 Questions 9 and There are two species of butterfly in the genus Flutterus that live in the same type of habitat. Individuals of F. colonius can disperse long distances, but populations of this species are prone to local extinction. Populations of the second species, F. persistus, are much more resistant to local extinction, but individuals are not very good dispersers. Question 9: Based only on the information provided so far, can you say which of these species will be more sensitive to habitat fragmentation that is, the conversion of many large habitat patches to fewer, smaller habitat patches? Explain your answer. No, can t say. Response depends on both c and e, and there is a trade-off between species in these parameters. Need more informaiton. Question : Now imagine that colonization (c) and extinction (e) rates for the Levins metapopulation model have been estimated for these two species. For F. colonius, c =.2 and e =.5. For F. persistus, c =.4 and e =.2. Does this new information change your answer from Question 9? Explain your answer. The equilibrium patch occupancy (a higher value of which means lower proneness to extinction) depends on the c/e ratio, and this is higher for F. persistus. So, F. colonius is more sensitive to habitat fragmentation. Question In North America, people s views of why nature is (or is not) important have shifted dramatically over the past few centuries. Give one example of this from the past, and also predict one important way in which people s values concerning nature or biodiversity will change over the next 5- years. Explain your answer. Anything reasonable is okay here. Expected common answer concerns predators: we use to kill them because they killed our livestock (or us), and now we protect them because we recognize their role in ecosystems. Question 2 Explain why the concept of shoot, shovel, and shut up represents a limitation to the United States Endangered Species Act. ESA applies to private land, so to avoid any restrictions on the use of your land, there is an incentive to make sure no one ever knows if an endangered species comes to live on your land (shoot it, bury it, don t tell anyone) 3

14 Question 3 In 2, the market for softwood timber in Canada followed the supply (positive slope) and demand (negative slope) curves shown in the diagram to the right. In 22, Canada began subsidizing (i.e., giving money to) the logging industry. Re-draw the diagram to the right showing any expected changes based on these new subsidies, and explain how the subsidies should influence the amount of forest logged. For a given cost of doing business (translated into price) timber companies can harvest more wood, so the supply curve (the one going up) goes down and to the right. The equilibrium point (where the curves intersect) also goes down to the right, so there will be more forest cut. (Equivalently, for a given amount of timber, it now costs less to produce ). Price per unit timber Amount of timber sold Questions 4 and 5 In a population of about squirrels on a small isolated island (Squirrel Island), the following experiment was conducted. Ten randomly chosen females were mated with males from the same island (treatment ), and ten different randomly chosen females were mated with males from a distant island of approximately the same size (treatment 2). The fitness of offspring from these matings was assessed on Squirrel Island. Question 4: If the offspring from treatment have lower survival and growth than the offspring from treatment 2, what biological term would apply to this situation? Give one specific reason for this outcome. Inbreeding depression (2 marks). Assuming individuals on the island are more closely related than individuals from different islands, there might be recessive deleterious alleles that come together in homozygous individuals more often (3 marks) Question 5: Give one possible reason that the offspring from treatment 2 might have lower survival and growth than the offspring from treatment. If populations are locally adapted, mating with individuals from other islands introduces maladapted alleles, and therefore lowers fitness. (There are more complicated explanations based on interactions among loci, but we didn t really talk about these) 4

15 Question 6 The data in the graph to the right are for Asian countries, and the curve is the bestfit quadratic regression. Give one possible reason that the poorest countries have a relatively low proportion of threatened species, and one possible reason that the richest countries have a relatively low proportion of threatened species. Poorest: They simply haven t exploited the economic potential of their natural resources yet (that s why they re poor), OR don t have the technology/initial resources to do so Richest: They can invest in conservation OR species have already gone extinct, leaving fewer in the threatened category Proportion of plant species threatened GDP per capita SECTION C The residents of Treehugger Island, which is one of the Southern Gulf Islands near Victoria B.C., have developed two possible plans for the establishment of ecological reserves (see Figure ). The total amount of land in ecological reserves is identical in the two options. They have hired you to provide them with advice on some specific conservation issues. Treehugger Island Option Treehugger Island Option 2 N N Treehuggerville Treehuggerville Background information on Treehugger Island: The island is physically heterogeneous, with hills, flatlands, streams, and a distinct coastline environment. B.C. 5 km FERRIES 5 km B.C. FERRIES Figure. Ecological reserve designs on Treehugger Island. Grey areas show proposed ecological reserves; the dashed line shows the only road on the island. The star shows the location of Treehuggerville. Very tall hills separate the northern and southern parts of the island. A single gravel road allows limited access to some parts of the island (Fig. ); otherwise travel must be by foot or all-terrain vehicle along hiking trails. The population of 5 residents is concentrated in the town of Treehuggerville, with some residents scattered in smaller settlements throughout the island. The island can be accessed only by ferry, which arrives in Treehuggerville. The natural vegetation is largely forest; streams running through the forest provide one of the only sources of clean water. Most of the island is covered with natural vegetation at present, except right in the town of Treehuggerville. Treehugger Island has relatively few exotic species, but other nearby islands and Vancouver Island have major problems with exotic plants. Areas outside the proposed reserves will be open to different kinds of development, including agriculture, logging, commercial buildings, and even some mineral extraction. 5

16 Question 7 Which of the two options do you expect to do the best job of conserving biodiversity across the whole island? Does your answer differ depending on the target organism(s)? Explain your answer. There is no general consensus on single small vs. several large, so one can t clearly be picked over the other. Basically, it depends ( marks). Organisms such as large top predators (e.g., cougars) require large areas, and so would benefit most from option (2 marks). With so much heterogeneity, organisms with smaller area requirements (e.g., plants, insects) will probably have higher total diversity in option 2 because the small patches cover a wider range of environmental conditions (2 marks) Question 8 How do the two options compare in terms of ecosystem services received by the residents of the island? Explain your answer. Clean water for drinking etc. is the main ecosystem service we know is provided by the natural vegetation (2.5 marks) Option 2 allows the residents much better access to this (and any other) services because there is natural habitat right next to town, and mountains make access to the reserve in option difficult (2.5 marks) Treehugger Island Option Treehugger Island Option 2 N Treehuggerville N Treehuggerville B.C. 5 km FERRIES 5 km B.C. FERRIES Figure. Ecological reserve designs on Treehugger Island. Grey areas show proposed ecological reserves; the dashed line shows the only road on the island. The star shows the location of Treehuggerville. 6

17 Question 9 Does one of the two options provide greater protection against the possibility of invasive plants becoming a problem within ecological reserve areas? Explain your answer. If roads are the main way exotic species arrive, option is worse because the only fragment is dissected by roads, where as option 2 has some fragments complete isolated from roads. OR If exotic species come in on edges, then option is better because it has a much lower edge:core ratio Question 2 If you could recommend one study that would help decide between the two options, what would it be and why? Explain your answer. The most logical study would be a biodiversity survey of different groups across the island to see which areas contain the most total biodiversity at present. High marks can be given for other logical answers. Things that are more tangential get lower marks (5 marks) 7

18 MIDTERM 29 Question : There are two species of butterfly in the genus Flutterus that live in the same type of habitat. Individuals of F. colonius can disperse long distances, but populations of this species are prone to local extinction. Populations of the second species, F. persistus, are much more resistant to local extinction, but individuals are not very good dispersers. Which of these species will be more sensitive to habitat fragmentation that is, the conversion of many large habitat patches to fewer, smaller habitat patches? Explain your answer. 5 marks There is a tradeoff here with respect to the two key aspects of habitat fragmentation: with less habitat, dispersal/colonization ability becomes more important to metapopulation viability (F. persistus more sensitive); with smaller patches, resistance to extinction becomes more important for metapopulation viability (F. colonius more sensitive). (3 marks for recognizing this tradeoff) Because each species is most sensitive to a different aspect of habitat fragmentation, overall either the two species should be equally sensitive or we don t know quite enough to say need more information on how these biological attributes translate quantitatively into colonization/extinction rates (2 marks) Question 2: Surveys of plant species were conducted in two parks in the Vancouver area of comparable size and similar environmental conditions, with the results shown in the table below (next page), where a indicates that a species was present in that park, and a indicates that it was absent from that park. Species (Latin name) Plantarinius communis Plantarinius backii Plantarinius gallolei Caryolaxus pratense Caryolaxus grandiflorum Dentolium pauciflorum Erigalia erigalius Actya bromolensus Brodo canadensis Maianthis petroides Big Hill Park Long Mountain Park (a) Based on this information, which park would you select as the higher priority for conservation? Provide two reasons for your answer. 5 marks 8

19 Species (Latin name) Plantarinius communis Plantarinius backii Plantarinius gallolei Caryolaxus pratense Caryolaxus grandiflorum Dentolium pauciflorum Erigalia erigalius Actya bromolensus Brodo canadensis Maianthis petroides Big Hill Park Long Mountain Park Big Hill Park - mark It has more species 2 marks The species it has are more genetically distinct 4/5 species in Long Mountain Park are in just 2 genera, whereas the species in Big Hill are all in different genera except 2 2 marks Notes: (i) With more species in Big Hill Park, and data for only two parks, it must be the case that more species occur only in this park, so that is not a different reason than the difference in species richness. (ii) Although many conservation schemes focus on species that are rare/endangered, or areas with lots of rare/endangered species, this would never lead you to focus on areas where there are already fewer species per se (e.g., where more species have already gone extinct), all else being equal. (b) Specify two specific additional pieces of information about these species that would help inform your prioritization decision, and explain how the new information might cause you to switch your choice. 5 marks There are a several possibilities here, but the two most obvious ones based on repeated discussion in class and tutorials are: () Which species are exotic? If most of the species on Big Hill are exotic, and the species unique to Long Mountain are native, we might switch our choice 2.5 marks (2) Which species are threatened/endangered? If the two species unique to Long Mountain are the only threatened ones regionally (i.e., all of the species on Big Hill are regionally abundant), we might switch our choice. 2.5 marks Full marks are possible for valid arguments based on abundance e.g., if all species are at very low abundance on Big Hill and vice versa for Long Mountain, perhaps we would switch our choice, or if evenness (a component of diversity) were much greater on Long Mountain we might switch our choice Other possibilities for partial marks: if species unique to Long Mountain are of particular economic or cultural importance, we might switch our choice. Note: just mentioning a factor is not enough for full marks you must also get the logic right (e.g., exotic species would cause a site to be less likely a priority for conservation) 9

20 Question 3: A researcher is interested in estimating λ, the per-year population growth rate, in a rare species for which there is limited quantitative information. A census in 26 found 48 individuals in the population, and a census in 28 found 2 individuals. (a) Assuming that l does not change from year to year, what is the best estimate of λ based on these data? 3 marks N2 = N*lambda = N*lambda 2 ; So, lambda = (N2/N) /2 =.5 (3 marks) You can also just figure (with out the square root) that you multiply by.5 twice to get from 48 to 2, but you still need to show/explain that 48*.5*.5=2 (b) Assume now that λ changes from year to year. Two different researchers have made extremely different claims concerning the population size of this species in 27. Dr. Highball says there were 72 individuals, while Dr. Lowball says there were 8 individuals. In addition to the information already provided, which of these population estimates for 27 would lead you to predict higher average long-term per-year population growth? Explain your answer. 5 marks Because in both cases the two estimates of λ are the same, the two estimates lead to the same predicted long-term population growth. Highball λ estimates: 72/48=.5, and 2/72=/6; Lowball λ estimates: 8/48=/6, and 2/8=.5 3 marks explaining why, 2 marks for the right answer 2

21 (a) Explain why the average per capita ecological footprint (see table) is different for the Yukon and Nunavut. Show how these two numbers (one for each territory) were calculated. 2 marks People 5+ years old have greater ecological footprints, and the Yukon has a greater proportion of their population in the 5+ category, so the average per capita ecological footprint is greater in the Yukon than in Nunavut. Yukon:.7*7 +.83*4.5 = Nunavut:.33*7 +.67*4.5 = marks for everything Part marks for the logic without showing how the numbers were calculate Footprint per Person (hectares of land) Y N Population Size (thousands) (b) Draw two points on the large graph above, one showing the current per capita ecological footprint for Yukon and one for Nunavut. Use the symbols Y and N for these two data points. 5 marks 2

22 Footprint per Person (hectares of land) Y 2 Y N N Population Size (thousands) (c) Assuming no changes in the age-specific birth or death rates or in the two territories, and no differences in immigration/emigration patterns, in what direction do you predict the ecological footprints of Yukon and Nunavut to change over the next 4 years? Draw two new points on the graph, Y2 and N2, showing where you predict the Yukon and Nunavut, respectively, to be in 4 years. Explain your answer. 5 marks Average per capita ecological footprint should go up in Nunavut because of all the 4 and under people moving into the 5+ age category, where the per capita footprint is higher. 2 marks Average per capita ecological footprint in the Yukon should go down because many/most of the people in the 4+ age category should be dead in 4 years, which should result in a reduced proportion of the population 5+ years old, where the per capita footprint is highest. 2 marks Footprint per Person (hectares of land) Population Size (thousands) Since most of the people in the Yukon are past reproductive age, this population is likely to decline. Since most of the people in Nunavut are at or below reproductive age, within 4 years this may lead to an increase in the population size (though this depends on the details of the matrix model). point Y 2 N 2 Y N 22

23 Average per capita ecological footprint should go up in Nunavut because of all the 4 and under people moving into the 5+ age category, where the per capita footprint is higher. 2 marks Average per capita ecological footprint in the Yukon should go down because many/most of the people in the 4+ age category should be dead in 4 years, which should result in a reduced proportion of the population 5+ years old, where the per capita footprint is highest. 2 marks Footprint per Person (hectares of land) Population Size (thousands) Since most of the people in the Yukon are past reproductive age, this population is likely to decline. Since most of the people in Nunavut are at or below reproductive age, within 4 years this may lead to an increase in the population size (though this depends on the details of the matrix model). point Notes: (i) Even though λ is close to., this only means that population size doesn t change once a stable age distribution has been reached. The Yukon almost certainly does not have a stable age distribution. (ii) This question is much the same as parts of the PVA tutorial. Given the exact same transition matrices, differences in population growth were found depending on the starting point (i.e., lots of juveniles vs. proportionally fewer juveniles) Y 2 N 2 Y N 23