FW 458 Final Exam

  1. Pleistocene Overkill
    • Martin 1984
    • Blitzkreig hypothesis/ "Clovis first"
    • Rapid settlement of Americans (12,900 yrs. bp)
    • Guided with glaciers
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    • Exponential Population Growth
    • Nt = N0ert
    • Colonization of empty habitat
    • After strong reduction of population size (e.g. removal)
  3. Intrinsic Growth Rate (rmax)
    • Maximum growth that is biologically possible for a given species
    • Scales to body size
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    • Density Dependence
    • Closed popualtion with no hunting or predators growing exponentially
    • Resulting in intraspecific competition
    • Population density can affect both fecundity and mortality
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    • Logistic Growth
    • dN/dt = rN (1-N/K)
  6. Carrying Capacity
    • "Maximum population size that the environment can support"
    • Often applied as a single-species concept
  7. Fertility
    • Pregnancy rate (# of fetuses)
    • Pregnancy rates don't decline until conditions are very bad
    • Fairly stable for most of the female's life
  8. Natality
    average number of live births per reproducing female ("litter size")
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    • Fecundity
    • Average number of offspring born for a given age/stage
    • Tends to show density dependence faster
    • Litter size shows big differences
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    • Recruitment
    • Number of offspring that survive to "adulthood"
  11. Net Recruitment
    Number of individuals added to population
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    Logistic Growth is just one of population growth with density dependence
  13. Characteristics of a population at Carrying Capacity
    • Natality / fecundity lower
    • Recruitment very low
    • Mortality (particularly of juveniles) is high
    • Individual quality/ condition is lower
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    • Time Lags
    • Popoulation Cycles response to habitat quality
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    • Oscillations
    • Trophic levels out of sink
    • Unlikely
  16. Oscillations
    • Gestations time (# of individuals born reflects habitat conditions in the previous year)
    • Long-lived species with high adult survival
    • Population and habitat (vegetation) cycle differently
    • Environmental stochasticity and predation
    • Stronger = growth rates are higher, and population close to K
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    • Irruption
    • The Kaibab Paradigm
    • Permanent Habitat Damage
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    • Irruption & dampened oscillations
    • Blacktailed deer on Angel Island
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    ICC & MSY (Stability Problem)
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    • KCC (equilibrium cc) & ICC (inflection cc)
    • Two concepts of carrying capacity
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    • Relative Deer Density
    • another CC concept
  22. Benefit of the RDD approach
    • Importance of different habitats for determining desired deer density
    • Not all management objectives or human values will be met
    • Helps compare deer populations in different environments
  23. Problems with the RDD approach
    • Need estimates (or indices) of K in different habitats
    • In absence of predation, require heavy harvest (both sex)
    • - Not always possible/practical/socially acceptable
  24. Limiting Factor
    • any process that causes mortality or affects birth rates (affects the rate of population change)
    • - both density dependent and independent
  25. Regulating Factor
    • Any process taht causes growth rate to decline as a population increases
    • - density dependence
  26. Bottom Up Control
    • Populations of herbivores are constrained primarily by plant availability, populations of predators are determined by herbivore availability
    • - depending on forbs
    • Competition dominant mechanism (intra and inter specific)
    • Population increase competition increase
    • Predator populations dependent on prey availability
  27. Top Down Control
    • populations of predators control herbivore populations, which in turn limits the impact on vegetation (depend on Apex predator)
    • predation dominant limiting herbivore populations
    • population prey increases population of predators increase
    • prey are not limited as strongly by intraspecific competition (e.g. lack of food)
  28. Intra-specific competition
    • Competition for resources among members of the same species (food, water, den sites, shelter)
    • Density Dependence
    • Affect sex and age classes differently
  29. Interspecific Competition
    • Concept of niche and resource partitioning
    • Species evolve separated niches to reduce interspecific competition
    • Stronger during times of limited resources
  30. Facilitation
    • One species improves habitat quality for another
    • Ex.: bison grazing encourages growth of forbs and improves forage availability for pronghorn anatelope
  31. Apparent Competition
    • Increase in one species causes a decline in another even though there is no direct competitive interaction
    • Ex.: whitetailed deer vs. elk, caribou, mule deer, moose
    • (Cote 2005: deer competitively exclude bear)
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    • Numerical Response Model
    • Change in predator # as prey increases
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    • i. predators regulate prey at low densities
    • ii. predators cannot regulate prey
    • iii. multiple stable states
  34. Compensatory
    Predators are killing prey that would have died anyway because of starvation, disease, etc.
  35. Additive
    Predators are killing prey that would have survived otherwise
  36. Predation Subsidized
    Predator has an alternative and abundance food source and therefore will not be limited by prey populations
  37. Mesopredator release
    • expansion in density or distribution, or the change in behavior of a middle-rank predator, resulting from a decline in the density or distribution of an apex predator.
    • Ex.: wolves, coyotes, pronghorn, forbs
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    • Harvest Management
    • Harvesting the same number every year
    • Two stable equilibria for any strategy other than MSY
    • Forecast environmental variation
    • Ex.: cougar in OR, black bear
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    • Harvest Management
    • Harvesting the same proportion every year
    • Forecast environmental variation
  40. Fixed Effort Harvesting
    • rather than setting a number of animals that can be removed each year, fix effort
    • season of a set length
    • limited number of hunters
    • population increases, kill will increase
  41. Harvest Management Goals
    • 1. Determine the status of the population
    • 2. Define the goals of the management program
    • 3. Establish a management strategy
    • 4. Determine how well the goals were achieved
  42. Linked Sex Harvest Strategy (LSHS)
    • McCullough 1990. (Black Box)
    • Harvest small number of antlerless deer along with usual male harvest
    • Harvest higher proportion of antlerless deer (later)
    • Slowly increase
    • Track sex ratio of the population
    • Track age structureof the harvested population
  43. The LSHS approach: predictions
    • Harvest of females will increase to levels similar that of males
    • sex ratio will move towards equality
    • female age structure will shift to lower age classes
    • harves of males will increase becasue of much higher recruitment of males and females.
  44. Sex-Age-Kill (SAK) Model
    • Extension of the harvest ratio population estimator
    • Good estimates of sex and age ratios
    • Good information on harvested animals (number and age)
    • Estimates of overall male mortality rate
  45. Fermentation
    • Microbes in the gut are used to break down cellulose in the plant cell walls and convert it to usable form
    • - Foregut fermenters (ruminants) x2
    • - Hindgut fermenters (off shoot)
    • - large animals = colonic fermenters
    • - small mammals = caecal fermenters
  46. Ruminant Digestion
    • Have four chambered stomachs
    • Fermentation allws herbivores to eat the structural parts of plants (leaves, shoots, twigs, buds)
    • No multicellular animal can break down cellulose enqymatically
  47. Cellulose breakdown by symbiossis
    • Bacteria and protozoa are maintained in the rumen
    • - cellulose broken down into volatile fatty acids
    • - rumen is anaerobic, buffered by NaHCO3 in ruminant saliva to keep pH correct
    • - bacteria = 60 -90% rumen mass
    • After fermentation, material moved through other chambers into "ture stomach" and into the small intestine for absorption
  48. Drawbacks to Rumen
    • maintained with a lot of water
    • can't handle fast changes in diet
  49. Passage Time
    • length of time that material stays in the gut
    • - longer passage time = more complete digestion
    • larger animals have larger rumens and longer passage time
  50. Important dietary elements
    • Energy (fats, oils, protein, starch & sugars, cellulose)
    • Protein (amino acids, ruminant have few AA's)
    • Water (free, preformed , metabolic)
    • Minearls
    • Vitamins
  51. Assessing "forage quality" for herbivores
    • Method 1: Clip pieces of preferred food plants and measure protein content (measure of nitrogen)
    • Method 2: Fecal nitrogen
  52. Macroelements
    • Minerals
    • large amounts
    • calcium, phosphorus, potassium, sodium, magnesium, chlorine, sulfur
  53. Trace Elements
    • minerals
    • smaller amounts
    • iron, zinc, manganese, copper, selenium, iodine, molybdenum, fluoride, chromium
  54. Mineral Deficiencies
    • Copper: twisted antlers, easy to break
    • Selenium: muscle and bone abnormalities, porr juvenile survival
  55. Fat Cycle
    • Seasonal variation (summer/winter, or wet/dry) causes forage and quality availability to vary
    • High quality (high energy, highly digestible) forage is available, store fat
    • Animals reduce forage intake to conserve fat
  56. Bergman's Rule
    • Surface to volume ratio also matters
    • - Larger animals don't loose heat fast
  57. Birth Synchrony revisited
    • not just a response to predation
    • an attempt to time reproduction for the most productive window of plant growth
  58. Predator Control
    • 1. Control of "top" predators to limit predation of game, endangered species, livestock, pets or humans
    • - selective (removing problem individual)
    • - non-selective ( aerial gunning / posion)
    • - non-selective, harvest based (encourage hunting)
    • 2. Control of mesopredators becasue top predators are absent
    • 3. Control of exotic predators
    • - non-selective
  59. Population Concepts of Disease
    Density Dependence: transmission increases linearly with host population density (social contacts)

    Independence (freq.) Dependence: rate at which hosts contact one another is independent of population density (sexual, vecot/host)
  60. Pasteurella Pneumonia Complex
    • Viruses, lungworms, scabies, internal parasites, fleas and ticks
    • Ex.: Hells Canyon - Rocky Mountain BHS
  61. Adenovirus Hemorrhagic Disease
    • Deer (whitetail deer)
    • Oral ulcers and abscesses
    • labored breathing (acute onset of pneumonia)
    • foaming or drooling at the mouth
    • diarrhea
    • weakness
    • emaciation
  62. Bluetongue/ Epizootic Hemorrhagic Disease
    • White-tailed deer, mule deer, pronghorn antelope
    • loss of appetite
    • weakness
    • excessive salivation
    • rapid pulse and respiration
    • hemorrhage and lack of oxygen results in blue
    • death 8-36 hours
  63. Poxvirus
    • Deer\Young self-limiting
    • Hair lose
  64. Trichinosis
    • Hogs, bear, fox, wolf, cougar, seal, walrus
    • blood test, cyst identification in muscle (tongue, masseter, diaphram)
  65. Chronic Wasting Disease
    • Deer (15 months) and Elk (12 months)
    • Progressive weight loss and eventual death
    • caused by prion transform proteins in brain to abnomral form
    • transmission is animal to animal (oral ingestion: saliva, feces, urine, contaminated soil/surfaces)
    • environmental contamination
  66. CWD Symptoms
    • teeth grinding
    • abnormal head posture
    • aspiration pneumonia from excessive salivation
    • clinical signs may occur with other illnesses and aren't diagnostic
  67. Intensive Management
    • Regulating a population by means other than habitat management and public harvest
    • Expensive
    • Overabundant populations where harvest is not permitted or practical
  68. How can we reduce populations where harvest is prohibited or ineffective (urban areas, national parks) - Overabundant populations
    • Capture and translocation
    • Contraception
    • Culling
  69. Capture
    • Logistically difficult (expensive and slow)
    • Disease risk
    • Liability risk for dangerous species
    • Poor Survival
  70. Contraception
    • More humane
    • Cost effective
    • Effective
    • Long-lasting
    • Doesn't drastically change behavior of target sp.
    • Easliy deliverable (darts, jabstick, oral)
    • Works: closed population (no emigration/immigration), tracked
  71. Culling
    • Removal and killing of surplus individuals by means other than public hunting not effective, feasible, acceptable
    • Removed by professionals that can employ restricted models
    • Results in fewer wounded animals
  72. Captive Breeding
    • Last resort
    • Expensive
    • Very careful tracking of pedigrees to prevent inbreeding
    • Ex.: Red and Mexican Wolves
  73. Translocation
    • Transporting individual to new or empty habitat
    • Important strategy for creating, increasing, or maintaining populations of some species
    • Adequate source population (disease-free, genetically diverse)
    • Mortality in new habitat is high
  74. Translocations: Soft Release
    Release animals at new site in a large protected pen to allow them to acclimate and recover from transport stress
  75. Game Ranching
    • Meat/ hide/ antler/ horn for commercial use
    • Raising animals for "canned" hunts
    • Ranches that offer "canned" hunts
    • Fee hunting
    • Wildlife viewing
  76. Why animals move
    • Dispersal: kin avoidance
    • Saturation dispersal: when population density become too high
  77. FST
    measure of genetic distance between populations (0 to 1)
Card Set
FW 458 Final Exam
FW 458 Final Exam Guide