Wlf 314 Wildlife Ecology I Fall 2009 Test 3 (100 pts) Answer Key

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1 Wlf 314 Wildlife Ecology I Fall 2009 Test 3 (100 pts) Answer Key ID # Reminders: Pay attention to all parts of a question and especially bold and underlined words. Use the number of points to guide you on how much detail to provide. Ask if a question is not clear. 1. How do ruminants that are grazers and browsers differ for the following characteristics? (6 pts) a) gut morphology Grazers have relatively larger rumens/foreguts and fewer or sparser papillae. Browsers have smaller rumens, more papillae. b) salivary glands Grazers have smaller salivary glands and browsers have larger ones that are used to help reduce the effects of plant chemicals on digestion. c) quality/characteristics of the foods they eat (e.g., grass vs. browse) Grasses have thicker cell walls, lots of cellulose, generally lower nutrition. Grasses also contain silica to deter feeding. Browse has thinner cell walls and more cell contents that are easily digested. Browse also more plant chemicals that inhibit digestion. 2. Which of the following statements about mating systems and sociality are True (T) or False (F)? (4 pts) a. Monogamy is the most common mating system in birds. T b. A lek represents one form of polyandry. F c. Polygny often occurs in species with precocial young. T d. Monogamy is the most common mating system in mammals. F 3. Briefly explain the main questions that Krissy Bush addressed when she spoke with you about her research on sage-grouse. (3 pts) Krissy examined 2 questions: 1) How related are individuals in a lek? If they are closely related, then kin selection might shape evolution of this mating system. 2) How many males are siring offspring and is there a big difference among males in their reproductive success? If so, then sexual selection might be shaping the mating patterns in lekking species. 4. Provide a brief definition of the following terms: (4 pts) a. eusocial obligate group-living; requires sociality to survive b. operational sex ratio the number of sexually receptive females to males at one time in a population

2 5. List and describe 3 advantages and 3 disadvantages of sociality. (9 pts) Advantages include ability to fend off predators through group defense, ability to detect predators, and potential for reduced individual predation in larger groups. In addition, information about food might be shared, there might be group care of young, or benefits with respect to thermal regulation. Disadvanges include increased conspicuousness to predators, potential for increased transmission of disease and parasites, increased competition for food and mates, or potential for increased rates of aggression. (others too most everyone got this one) 6. Why might population density be a poor indicator of high habitat quality? What did Van Horne (1983) and Hall et al. (1997) suggest as a better (functional) indicator of habitat quality? (5 pts) Population density might be high in areas that are, in fact, poor or marginal habitat if the best habitats are occupied by dominant or territorial individuals. Also, animals might group up for other reasons (breeding or to avoid harsh climatic conditions), but those areas might not be good habitat. The authors that we read suggested that survival and reproduction (i.e. fitness) and population persistence are better measures of habitat quality. High quality habitat should promote individual fitness and population persistence. 7. Briefly define each of the terms below in terms of how you would measure each. (9 pts) Habitat use: resources that an individual uses (measure use of resources either directly or indirectly) Habitat selection: this is what an individual chooses to use measured by comparing relative use with relative availability of resources in the environment Habitat preference: what an animal would choose if all possible resources were equally available rarely measured in natural systems, but can be measured in a captive situation 8. Briefly describe how the wildlife that occurs in North America today has been influenced by the following things. (8 pts) a) Great American Interchange of mammals The formation of a connection between North and South America allowed animals to be exchanged between continents. A few of the species that crossed into NA survive here today, including the armadillo, opossum, and porcupine. b) Activities of humans during the Pleistocene Humans crossed the Bering Land Bridge into North America and hunted many of the large mammals. An estimated 75% of large species were driven to extinction by human hunters.

3 c) Activities of humans in the 1800s and early 1900s European settlers perceived wildlife as unlimited and hunted wildlife for commercial markets. Many species were driven to extinction (Passenger Pigeon, Heath Hen, Carolina Parakeet) and others were greatly reduced (elk, bison, white-tailed deer). d) Your generation s activities (I m asking you to speculate here) I hope for the best. 9. Which characteristics characterize the Order Perissodactyla vs. the order Artiodactyla? Use a "P" or "A" to indicate your answer. (4 pts) a) hind-gut fermentors _P b) less sexually dimorphic _P c) higher species diversity _A d) odd numbers of toes _P 10. What characteristics represent adaptations for the cursorial lifestyle of ungulates? You may circle more than one. (4 pts) a) strong and rigid spine b) unguligrade feet c) springing ligament d) heavier foot bones 11. Which North American ungulates typically or commonly have more than one young at a time (meaning twin births or more)? You may circle more than one. (4 pts) a) Odocoileus virginianus b) Ovis canadensis c) Antilocapra americana d) Alces alces 12. Which statements about ungulates in North America are True (T) or False (F)? (4 pts) a) A tending-bond mating system is characteristic of the Cervidae. T b) Four families of ungulates occur in Idaho. F c) Of the Bovidae that occur in Idaho, Oreamnos americanus is the least sexually dimorphic. _T d) Cervus elaphus is the only Cervid in North America in which both sexes have antlers. F

4 13. You read the executive summary of the report by Committee on Ungulate Management in Yellowstone National Park titled Ecological Dynamics on Yellowstone's Northern Range. a) What were the 2 primary questions addressed by the panel? (2 pts) Is overgrazing on the Northern Range of Yellowstone NP causing significant damage to the vegetation? Should natural regulation be permitted or how should the National Park Service manage the ungulates? b) What were their major conclusions and recommendations for management? (4 pts) The range is not likely to have a collapse in function in the near future. Targeted protection of vegetation like aspens could help with recruitment. The system is much influenced by humans and natural regulation might not be completely possible. Adaptive management should proceed with planned research to evaluate long-term impacts to the range. 14. a) Name 1 ungulate species that has a wider distribution in North American today than it had historically and explain why. (2 pts) White-tailed deer change in habitat including harvesting of forests in the east and planting of trees and shrubs across the prairie helped the species to expand after hunting was regulated. b) Name 2 ungulate species that have more restricted distributions today than historically and explain why. (4 pts) Bison, bighorn sheep, elk, pronghorn 15. Explain the general trend of sexual dimorphism in body size and antlers/horns that characterizes the ungulates. How has sexual selection favored evolution of sexual dimorphism in ungulates, and which type of sexual selection? (5 pts) In general, male ungulates are larger than females and tend to have secondary sexual characteristics like horns or antlers. When females have horns, they tend to be smaller. The degree of sexual dimorphism increases with body size. Intrasexual selection has likely favored the evolution of large size and antlers/horns in males that compete for breeding access to females. 16. Provide the common name of an Idaho bat that might fit the following description (note: there might be more than one correct answer, but just provide one species). (4 pts) a) typically has twins _pallid, silver-haired, hoary, western pipistrelle b) roosts in tree cavities or under tree bark just about any (but probably not spotted or pallid) c) fur is a distinctive pattern of black and white spots _spotted bat d) the largest bat in Idaho and one of the largest in North America hoary (but ½ pt for big brown bat)

5 17. Answer one of the following questions: (6 pts) -What did you find out about white-nosed syndrome in bats? - How are wind turbines killing so many bats? White-nosed syndrome is a fungus that was discovered only in 2006 in hibernating bats in the northeast US. It appears on the noses of bats in caves during hibernation and kills many bats, possibly because it interferes with their hibernation and causes them to use energy reserves so that they die of starvation. Wind turbines kill thousands of bats each year. Migratory tree bats are the most dramatically affected. While some bats hit the turbines, many die from hemorrhaging in their lungs caused by the drops in air pressure around the spinning turbines 18. Briefly contrast the Megachiroptera and Microchiroptera for the following characteristics: (8 pts) a) diversity of species and distribution Mega occur only in the Old World and consist of only 1 family. The Micro occur across the world and make up 16 of the 17 families of bats. b) foods eaten Mega eat primarily fruits and flowers. Micro have diverse diets (nectar, fish, blood, etc.), but most are insect eaters. c) morphology Mega are larger, have larger eyes and less complex ears & noses (dog-faced bats). Micro are smaller in size, and tend to have smaller eyes and more complex ears and nose leafs. d) sensory abilities Mega rely more on sight and smell and less on echolocation. Some make other sounds for communication. Micro rely on echolocation for navigation and catching food poorer eyesight. Extra Credit: In the assigned reading on bats, what did the author suggest were the functions of hairs on the top and the bottom of the uropatagium. (2 pts) Top helps with airflow for flight Bottom helps in catching and holding insects