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LEC242 continued

Anna Hollywood BIOLOGY DEGREE LEVEL Inglés 168 fichas

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  1. 1How does the proximity of reserves have an effect on species?Shorter distances = increase chance of recolonisation and helps prevent loss of genetic diversity due to inbreeding
    Longer distances = help reduces the spread of diseases and invasive species between reserves and increases the likelihood that some reserves will avoid the impacts of a major distrubance
  2. 2What are the arguments for 'more shared' habitat and 'less shared' habitat?More shared = larger area of target habitats, increasing the pop. size of target species dependent on those habitats
    Less shared = likely to capture more habitat heterogeneity, and therefore
    greater species diversity
  3. 3What are the 2 types of reserve connectivity?Structural connectivity (physical connection of reserves) and functional connectivity (species of interest can disperse between reserves)
  4. 4How can functional connectivity be lost?By reducing the species dispersal ability or by increasing the hostility of the matrix habitat in between the patches
  5. 5What did Beier and Noss show about connectivity?Conducted a review of 32 studies on
    corridors and connectivity:
    -10 of 12 well-designed studies demonstrated positive effects of corridors
    - Those that did not find an effect were generally poorly designed
  6. 6Which are better out of round and elongated reserves?Rounder reserves have lower edgeto-area ratios than elongated reserves so they therefore minimize the amount of area that is subject to edge effects - edge effects can extend far into patches of remnant forest
  7. 7When may elongated reserves be appropriate?E.g. the conservation of riparian habitats (riparian area is the interface between land and a river or stream)
  8. 8EVIDENCE FOR RESERVE DESIGN BEING CONTEXT-DEPENDENT: Give an example of a species best conserved at a single siteThe frog E.corona is restricted to just 10km^2 in Haiti
  9. 9EVIDENCE FOR RESERVE DESIGN BEING CONTEXT-DEPENDENT: Give an example of a species best conserved at a network of sitesThe black lion tamarin occurs in 9 isolated forest fragments - enhancing connectivity is crucial
  10. 10EVIDENCE FOR RESERVE DESIGN BEING CONTEXT-DEPENDENT: Give an example of a species best conserved at a network of sites complemented by broad-scale conservation actionThe leatherback turtle
    nests at discrete beaches where it is
    threatened by egg collection, but is also
    threatened by bycatch and pollution throughout the tropical and temperate oceans
  11. 11EVIDENCE FOR RESERVE DESIGN BEING CONTEXT-DEPENDENT: Give an example of a species best conserved through broad-scale conservation action (rather than using reserves)The Indian vulture is threatened by poisoning from feeding on dead livestock that have been treated with the veterinary drug diclofenac
  12. 12Beyond reserves, what are there other options for the conservation of biodiversity?Legislation; improve habitats outside reserves e.g. hedegrow planting, field margins - using money incentives from the government to farmers; quotas e.g. fishing quotas; education to help avoid human-wildlife conflict; ex-situ conservation
  13. 13What percentage of the planet's land surface is covered by protected areas? What percentage of the land in 9 of the major 14 biomes do they represent?10-16%; >10%
  14. 14.....% of mammal species are not represented in any protected area, and many are represented in areas but are unlikely to be able to ...... in the long term (as of 2004)12; survive
  15. 15How have protected areas in the Amazon been successful?Lower rates of deforestation and fires inside of reserves compared to outside reserves
  16. 16Give evidence for tropical parks not always workingDeforestation inside the park increased exponentially when the surrounding land was fully deforested in Bom Futuro National Forest, Rondonia, Brazil; Deforestation inside the park increased when the buffer was fully deforested (i.e. no alternative forest to cut down) in Borneo Park
  17. 17What have park measurements failed to include?Leakage - the creation of parks protects the forests within the park but may have pushed deforestation elsewhere - as a result, there could be no net change in the rate of deforestation overall
  18. 18When including the effects of leakage in surrounding areas, how did the review of Costa Rica's parks change?A corrected analysis of Costa Rica’s parks reduced their influence on reducing deforestation from 65% to 10%
  19. 19What is PADDD?Protected Area Downgrading, Downsizing and Degazettement (degazettement = removal of a reserves status)
  20. 20Ecological restoration is......the process of assisting the recovery of an ecosystem that has been degraded, damaged or destroyed (IUCN definition)
  21. 21What did the global policy, CBD (Convention of Biological Diversity) (1992) say that each party shall do?Each Party shall “rehabilitate and restore
    degraded ecosystems and promote the recovery of threatened species”
  22. 22What key ecological concepts does restoration ecology draw on?Succession; competition; predation; nutrient limitation; facilitation; resilience; resistance; dispersal; scale-dependence
  23. 23What are ecosystem phase-shifts?Where an ecosystem flips to a different stable state (for example from a coral-dominated reef to an algae-dominated reef)
  24. 24What is restoration therefore about in terms of ecosystem phase shifts?Getting them back to their original state
  25. 25What are some examples of things that can happen that requires restoration?Natural disasters (St Helen's eruption, 1980); human-caused disasters (Exxon Valdez oil spill, Alaska, 1989); cleaning up after industry (mining - spoils, and open cast mines); response to environmental change (managed retreat of sea defences - also called managed realignment)
  26. 26What are two things to consider when carrying out restoration?- Restoring biodiversity e.g. native succession (results in higher levels of biodiversity and smaller carbon stocks
    - Restoring ecosystem value e.g. exotic Eucalyptus plantations (results in much lower levels of biodiversity and higher carbon stocks)
  27. 27Ecosystems can have a very high value: US$............. annually (Costanza et al. 1997)33 trillion
  28. 28Some species groups have a big impact: e.g. faeces burial by dung beetles may be worth $............. a year in the USA (Losey and Vaughan 2006 Bioscience)380 million
  29. 29Give some examples of valuable functions provided by ecosystemsGas regulation; disturbance regulation; water regulation; pollination; biological control; food production; recreation; cultural
  30. 30What are some possible components to measure when looking at restoring biodiversity?Keystone species (species with important role in the ecosystem, charismatic species); endangered species (the red list, endemic species); an assemblage of species (which taxa to examine?)
  31. 31What are the 2 different reference systems used to measure recovery?- Historical reference ecosystem: aims to restore ecosystem to something similar to historical reference site (but lack of information and debate on how far you should go back)
    - Modern reference ecosystem: based on modern likely equivalent; what would likely be there based on other similar sites (shifting baselines)
  32. 32What are some of the solutions?Do not constrain aims by 'historical fidelity' (establish ecosystems that are able to persist in future environment); accept that ecosystem processes are dynamic (set alternative goals for restoration, that allow for unforseen changes); set goals of restoration within an economically and socially acceptable framework; focus on ecosystem functions rather than species communities
  33. 33What is re-wilding?Turning a managed area back to the wild in the form of a self-sustaining ecosystem, using minimal intervention e.g. Wild Ennerdale aims 'to allow the evolution of Ennerdale as a wild valley for the benefit of people, relying more on the natural processes to shape its landscape and ecology'
  34. 34Give examples of animals that have been reintroduced into the UK after their evolutionary counterparts have become extinctBeavers; wolves; lynx
  35. 35What are 2 key considerations of restoration programs?Restoration goals are subjective (what time period in the past should be the target of restoration? also need to consider magnitude and scale); applies a static approach to dynamic ecosystems (climate change, species invasions etc.; impractical in face of irreplaceable losses - key species may be lost permanently)
  36. 36What are the 3 concepts on how nature is viewed?- Wilderness concept - natural implies no
    human influence at all
    – Arcadian concept – natural includes semi-natural landscapes (idea of a simple and happy life in the country)
    – Functional concept – nature is there to be used by humans (provides services such as clean water, carbon sequestration, amenity land etc).
  37. 37What are the 3 types of diversity?Phylogenetic; functional; species
  38. 38Give an example of differences between these diversity types. What is the most useful diversity to look at?Darwin's finches - In the case of phylogenetic diversity, functional diversity reflects it in the different beak types (reflecting different feeding types)
    - Species diversity is most commonly used as can be a good surrogate of many facets of diversity and is relatively easy to measure; used to classifying organisms this way (lots of info already exists)
  39. 39How does speciation and diversity increase through geological time?Increase in the number of radiolarian species by 10x over 500 MY; increase in the number of land plants; increase in the number of insect families from 0-600 over 400 million years; increase in the number of tetrapod families by 300 in 350 MY
  40. 40Give an example how dominant taxa have changed over timeAngiosperms have become the dominant taxa over the last 100 MY, used to be gymnosperms and before that it was pteridophytes
  41. 41What have been the 5 mass extinctions that have occurred in the past?End-Ordovician, late-Devonian, end-Permian, end-Triassic and end-Cretaceous
  42. 42How has the extinction rate changed over geological time?In the distant past (when the fossil record was from), <1 in 1000 mammal species went extinct every millenium; in the recent past (known extinctions) the rate is up to 1000 times higher than the fossil record; the projected future extinction rate is more than 10 times higher than current rate
  43. 43What part of the world has the highest plant species density?South America (e.g. Brazil) - shows that the distribution of species diversity is uequal
  44. 44Give some examples of different latitudinal gradients that different organisms exhibitMarine bivalves most prevalent at equator, butterflies most prevalent slightly South; mammals and trees most prevalent in the South
  45. 45What is the intrinsic value of biodiversity?Organisms have interests of their own; they have inherent value (irrespective of value to us)
  46. 46Who accepts intrinsic value as a valid value? Who rejects it?Biocentrists - they argue that as soon as something is given a cash value it becomes vulnerable
    Anthropocentrists - reject it as an idea
    - There has been a cultural shift from biocentrism to anthropocentrism
  47. 47What is the instrumental/utilitarian value of an organism?Anthropocentric; about the goods, services and information we can obtain from them; about their psychological/spiritual value - ecosystem services
  48. 48What are the types of ecosystem services?- Provisioning services (products obtained from ecosystems: fuel, water, food etc.)
    - Regulating services (benefits obtained from ecosystem regulation: climate, disease, pests)
    - Cultural services (spiritual, religion, recreation, aesthetic, educational)
    - Supporting services (necessary for production of other ecosystem services: soil formation, nutrient cycling)
  49. 49What did Constanza et al. (1997) estimate the total global ecosystem services to be in dollars per year?$3.33 x 10^13 per year (= 1.8 x GNP)
  50. 50What has happened to the estimated value of ecosystem services since the 1997 paper (talked about in 2014 paper brought out by Constanza et al.)?Estimated value of Ecosystem Services has decreased considerably since 1997 due to
    habitat loss and ecosystem change
  51. 51Why do some people argue that monetization of ecosystem services is a mistake?It devalues nature; methods used to monetize some services do not capture the true value; ecosystem services are not synonymous with biodiversity; does not biodiversity - markets lead to exploitation
    (resurgent biocentrism?)
  52. 52What relationship did they find between the percentage of parasites present to kill the pests that feed on the crops and the crop heterogeneity? What relationship did they find between number of destroyed buds in European oil-seed rape and crop heterogeneity?Thies & Tscharntke (1999):
    Less parasitism towards in pests in simpler, monocrop areas; therefore there was a higher percentage of destroyed buds in these simpler monocrop areas
  53. 53Give an example commercially where pollination is very importantCalifornian watermelons need 1000 pollen grains to make a marketable fruit; pollination increases with species richness of bees (wild pollination is quickly eroded as species richness declines)
  54. 54What did Steinbeiss et al. find out about carbon storage in 2002?That European grassland communities with reduced species diversity may store less carbon
  55. 55What did Tilman et al. find in their experiments with plant communities in 2001?Aboveground biomass and total biomass seemed to increase with the total number of species in that community
  56. 56What did Isbell et al. find when looking at the responses of ecosystem productivity to climate extremes in 2015?Looked at data from 46 grassland diversity experiments across Europe and N. America; found that there was an increase ecosystem stability and resistance with increasing number of species
  57. 57Since species are generally functionally ......, .......... species diversity results in ......... levels of functioningDistinct; decreased; decreased
  58. 58Therefore what does decreasing diversity result in?Impaired ability to withstand environmental perturbation and increased variability in time of ecosystem processes
  59. 59What did Allan et al. find about ecosystem services and land-use intensification in 2015?Depending on what your values are regarding land-use intensification different changing factors have different positive and negative impacts - different results are even found in different areas
  60. 60MAXWELL ET AL. (2017) What are some of the biggest threats to the (8,688 as of 2017) threatened and near-threatened species globally?1) 6241 - overexploitation (e.g. logging, hunting, fishing, gathering plants)
    2) 5407 - agriculture (e.g. crop farming, livestock farming, timber plantations)
    3) 3014 - urban development (e.g. housing, tourism, industry)
  61. 61Name some anthropogenic causes of habitat loss/degradationAgriculture, contamination, roads, fire, erosion, desertification, deforestation
  62. 62Where are cultivated systems (areas in which at least 30% of the landscape is cultivated) found the least?Areas of extreme temperatures, mountainous areas, protected areas (like rainforests) etc.
  63. 63What is a key driver in agricultural growth?- Global population doubled in 40 years (1960-2000)
    - Projected to grow to between 8.1 and 9.6 billion by 2050
  64. 64How has the calories per day changed from 1961 to 2009?Countries are eating a lot more calories than they did previously; for example, China used to consume below 1600 kcals a day and now they have ~3000 kcals a day
  65. 65How much did the global cereal production increase by between 1980 and 2001?36%
  66. 66How much did the land area in permanent crops increase by between 1980 and 2001?34%
  67. 67How much did the nitrogen fertiliser use increase by between 1980 and 2001?34%
  68. 68Developed countries ......... calories per day per capita, developing countries ........ (1999-2001)3260; 2680
  69. 69How much has the percentage of undernourishment decreased by in developing countries from 1990-92 to 2014-16?10.4%
  70. 70More land was converted to cropland in the ....... years after 1950 than in the ...... years between ...... and 185030; 150; 1700
  71. 71What has the largest proportion of projected loss by 2050?Tropical and sub-tropical coniferous forests
  72. 72What relationship can we see between habitat loss and species richness?More habitat loss = less species richness
    e.g. mature vegetation has more species richness then cropland, pastures and urban areas (Newbold et al., 2015)
  73. 73Name some of the countries with the largest net change in local richness caused by land use and related pressures by 2000 (Newbold et al., 2015)Sub-Saharan Africa; U.S.; Argentina, Brazil, India, Turkey etc.
  74. 74What is the equation for the relationship between species richness and area?Species richness = (fitted constant) x area^(another fitted constant)
    - Results in a logarithmic curve
    - This can be linearised by logging it
  75. 75What happens when z=0.35 and loss of area is 90%? What about when z=2 and loss of area is 90%?z=0.35 --> species richness reduced by 55%
    z=2 --> species richness reduced by 37.5%
  76. 76What are some of the causes of species loss as area is reduced?- Habitat diversity = lose heterogeneity due to loss of micro-climates/habitats (larger areas contain a greater variety of habitats)
    - Sampling (non-biological mechanism) – larger areas contain more individuals
    - Population size - large area = larger populations, smaller populations more likely to go extinct
  77. 77Why does habitat fragmentation hold fewer species than similar areas of contiguous habitat- Home range may be bigger than fragment (e.g. grizzly bears 900km^2)
    - If matrix is inhospitable then sub-populations will be isolated and so are more likely to go extinct
    - Edge effects e.g. nest predation rates are often higher at the edge
  78. 78What are some of things that need to be considered when looking at edge effects?- Fragment shape matters – long thin and
    irregular shapes have higher edge:area
    - Edge effects can extend great distances into fragments
    - Even closely related species can respond
    differently to fragment edges
  79. 79What did they find when looking at beetles in forest fragments in New Zealand?Mix - some beetles preffered the original habitat and some thrived at the edge
  80. 80What can be said about how species respond to the matrix?Different species will respond differently to
    boundaries and matrix between patches; some species may be able to utilise the matrix area between patches (becomes less likely as the habitat contrast increases)
  81. 81How could the matrix affect mortality rates?The matrix may be a barrier to movement, but may also increase mortality, particularly if patches are separated by road
  82. 82Give a case study giving evidence for the fact that matrix properties govern species response to the patch edgeNZ native forest patches adjacent to pasture (open circles) and pine plantations
    (filled circles):
    - Coleoptera - less found in pasture matrix than pine matrix
    - Hemiptera - more found in pasture matrix than pine matrix
    - Diplopoda - virtually none found in pasture matrix, lots found in pine matrix
  83. 83What is the citation for this study?(Campbell et al., 2011)
  84. 84What else can cause habitat fragmentation?Road installation - box turtles and rattlesnakes in Illinois, USA; had quite a high frequency of road crossings to get between different habitat patches
  85. 85Newly created islands ....... species through ........; remnant islands ....... species by .........Accumulate; colonisation; lose; relaxation
  86. 86What happened when looking at the fragmentation of moss on rocks in Derbyshire?Species richness decreased quite a lot in the first 2 months, peaked 2 months later and then slowly declined again
  87. 87What shows evidence of relaxation?Less large mammals found in forest fragments in Queensland, Australia in 2006-07 than when sampled in 1986-87
  88. 88Why can species richness temporarily appear to go up after fragmentation?Due to species over a larger area being grouped into a smaller area (the 'crowding effect') - often ends in a 'nested subset' of the original community
  89. 89What was found by Newmark (1987) when looking at the number of extinctions in North American National Parks?Negative correlation between an increase in park size and the number of extinctions
  90. 90Loss of species is non-random. The following are more likely to be lost following fragmentation:Naturally rare species; wide ranging species; poorly dispersing species; species with low fecundity; short-lived species
  91. 91What is the history of humans and over-exploitation of land?- Initially hunter-gatherers: nomadic habit allowed over-exploitation of small areas but impacts were minimal and localised due to small population sizes and recovery of areas was allowed as people moved
  92. 92What happens as populations grew?New areas were colonised and many large species were quickly extirpated; despite considerable land conversion for agriculture, wild harvesting is still a major human activity in the developing and, to a lesser extent, developed world
  93. 93Give an example of a large mammal that showed a large decrease in range sizeIn 1870 bisons had a fairly large range over the US; in 1889 the range was a lot smaller
  94. 94How has human colonisation impacted on the percentage of genetic extinctions of different body-massed animals?100% of 1000+kg extinct
    75% of 100-1000kg extinct
    41% of 5-100kg extinct
    1.3% of 0.01-5kg extinct
  95. 95How has human colonisation impacted on the survival rates in different countries?Significant decreases in survival rates since human colonisation in Australia, North America and Madgascar - drop not as significant in Africa
  96. 96How has hunting impacted on ecosystems?- Extinction or near extinction of many high
    profile species (e.g. passenger pigeon, American bison)
    - Bushmeat problem; threatens species like chimpanzees
    - Many fish stocks severely reduced (e.g. Atlantic cod)
  97. 97Over-hunting is the major problem for ...... of threatened mammals and birds1/3
  98. 98How many mammal species were found to be traded on market stalls when surveying 7 countries in central Africa?71
  99. 99How many large vertebrates have been lost from Vietnam since 1960s?12
  100. 100What happened to the Atlantic cod stocks off the East coast of Newfoundland?Fairly constant amount of cod harvested from 1850-1950; in 1950 they developed new technologies which could fish deeper and exploit more of the cod poplulation; this led to a complete collapse of the fishery in 1992; it has now been reopened with very limited fishing under national regulation
  101. 101What has happened with whale harvesting?Lots of whales were harvested from ~1945 to 1980 with the biggest whales like the blue whale and the fin whale being caught first then as their populations depleted smaller whales were caught - 1980 saw strict conservation regulations which banned whale hunting
  102. 102What can be said about wild meat hunting in tropical forests?- Productivity for wild meat = 10x greater than in open habitats like savannahs
    - High human pop. densities (>1km^-2) are unsustainable in tropical forests (if dependent of wild meat for protein)
  103. 103Considering human population densities > 1 km^-2 are unsustainable in tropical forests (if dependent on wild meat for protein), how does this compare to current population densities?Currently there are 522 people km^-2 in SE Asian forests, 90 in W/Central Africa; 46 in Latin America; the population of Africa increased 8-fold in the 20th century
  104. 104When looking at 36 sites across Central and West Africa, what are the most commonly hunted groups? What group comprises 55% of biomass harvested?Ungulates (47%) and rodents (37%); large mammals
  105. 105How does the biomass of all mammals; large, preferred mammals; secondary game mammals; bats, mice and rats differ with increasing hunting pressure?All - Decreases
    Large, preferred - Decreases quicker
    Secondary game - Increases then decreases
    Bats, mice and rats - Increases
  106. 106Wild meat in Ghana case study (Brashares et al., 2004)Hunting in reserves increases when fish catch decreases; fish supply in markets is negatively correlated with sales of wild meat; the link between fish supply and estimated mammal biomass is much stronger close to the coast
  107. 107How much did the fish catch increase since 1950 in Ghana? What about in the EU?10x; EU (subsided) catch increased 20x over the same period
  108. 108Give an example of how availability affects food priceIn Libreville in New Guinea poultry is more abundant than wild meat (porcupines) so wild meat is more expensive here; as you go further inland you find that the opposite is the case so poultry is a lot more expensive in places like Villages - consumption reflects this market price
  109. 109Why is this happening?Meat is often a key food and cash earner for people on the geographical fringe of the economy; lack of development means lack of access to livestock in these more rural areas so rely on hunting of wild meat; these people often have meat consumption 10x higher than urban poor
  110. 110Give an example of how hunting has acted as an effective selection pressureIn the North-East Atlantic cod; naturally larger cod have lower mortality rates; hunting has meant that larger cod now have higher mortality rate; this has lead to a decrease in the age at which these cod reach sexual maturity (used to be 9 years old in 1930 and is now around 6 years)
  111. 111How can a similar effect be seen in rock lobsters in WA?They have a reduced carapace length (been constantly reducing since 1970) partly as a result of removal of larger individuals and partly evolution towards a smaller body size
  112. 112How has tusk harvesting acted as a selection pressure on the African elephants?There has been a documented increase in the proportion of tuskless females in African elephants
    - 10.5 % in 1969 to 38.2 % in 1989
    - South Luangwa National Park, Zambia
    - Also seen an overall decrease in tusk length in males and females since 1960s
  113. 113How has trophy hunting acted as a selection pressure on bighorn sheep?Trophy hunting focuses on large-horned males; resulting in a decline in horn length of males (documented since 1970)
  114. 114What is the logistic population model?Density dependence regulated population size - population will increase if the carrying capacity>population size and vice versa (pop. will be equilibrium when it reaches carry capacity)
  115. 115Apart from density dependence, what else do conservation biologists need to take into account when looking at population persistance, particularly when populations are small?Genetic effects, environmental stochasticity and demographic effects
  116. 116What is the norm to happen to populations and why?The norm is for populations to fluctuate widely due to density-independent effects
  117. 117Why is the logistic population model too simple?Carrying capacity is not likely to be constant; birth and death rates change with environmental variability; species probably vary in the extent to which stochastic environmental factors influence population size
  118. 118Give an example of how the introduction of a new predator can have a great effect on a speciesThe Stephen's Island wren was a flightless passerine and the lighthouse keeper's cat exterminated the species before it was even officially described in 1894
  119. 119What happened the saiga population in May 2015?200,000 died in the space of 2 weeks (~40% of the population) due to a bacterial infection (normally commensal) and thought to be linked to poor spring weather
  120. 120What is the Allee effect?Rapid reduction in population viability below a threshold value; below this value populations may enter an 'extinction vortex' and be unable to recover
  121. 121What are some contributing factors to these Allee effects?Difficulty in mate location; reduced group defence against predators; reduced group foraging efficiency; breakdown of social integration; chance inequality in the sex ratio (particularly in a reduction of females)
  122. 122How does population size affect African wild dogs?Need to hunt in packs to be successful; can see this between positive correlation of pack size and calorie intake; also need to make sure there is enough to 'baby-sit' the pups so that the next generation can survive and prosper to keep the pack size large
  123. 123Give an example of a species that went extinct due to a skewed sex ratioThe dusky seaside sparrow went extinct as there was only 6 individuals left and they were all male - last female observed was in 1975
  124. 124How did the dusky seaside sparrow populations get so low?1940s DDT sprayed on the marshes to
    control mosquitoes – population fell from 2000 to 600 breeding pairs; key breeding sites were then removed as Merritt Island was flooded to control mosquitoes around the Kennedy space centre; marshes were then drained to allow construction
  125. 125The percentage of ..... species going extinct on Californian Islands over the last 80 years has been strongly correlated to the ....... ......Bird; population size
  126. 126How is the conservation of species in-situ complicated by spatial effects?May be good quality and bad quality habitat patches within a habitat which will affect the success of reproduction in different species; good habitats ('sources') may supplement population size in bad habitats ('sinks')
  127. 127What does this mean in terms of conservation?Can't take for granted that all the patches are the same quality - if some of the bad patches are lost the impact will be less than if some of the good patches are lost; still it is quite hard to determine the quality of a habitat
  128. 128What is a metapopulation?A population made from several sub-populations that are linked together by immigration and emmigration
  129. 129What have studies shown about the proportions of the metapopulation that are living in 'source' habitats and 'sink' habitats?Studies have shown that as little as 10% of the population may be found in the source population maintaining 90% in sinks
  130. 130Why can conservationists not just focus their attempts on sites where a species is most common?As this might not be the most productive site and so the efforts may be doomed to fail
  131. 131What sort of patches can the house sparrow be found in on Norwegian Islands?Has populations on 4 Norwegian Islands; 2 of these islands are sinks (due to poor juvenile survival) and 2 are sources (but even the most productive site was a sink in one year)
  132. 132What can be said about patch quality having a disproportionate influence on metapopulation persistance and the Sinai baton blue butterfly species?Food source: Sinai thyme (endangered and grows at high elevations)
    - There are 2 especially important patches containing Sinai thyme, modelling predicts that if these 2 specific patches are lost the chance of the butterfly's extinction within 200 years is 80% (loss of other patches is only 20% chance of extinction)
  133. 133How do the sub-populations of the high brown fritillary butterfly respond differently to small size?- Lives in coppice woodland
    - >70% show Allee effects (dispersal reducing mating)
    - 34% also show rescue effects due to recolonisation (meta-population)
  134. 134What is a PVA model?PVA = Population Viability Analysis
    - Models to predict the likelihood of extinction taking into account the variety of factors influencing population size, and sometimes metapopulation structure
    - Takes into account demographic uncertainty, genetic uncertainty, environmental uncertainty & natural catastrophes
  135. 135How is uncertainty added into the model?- If the equation is N(subscript t+1) = N(subscript t) x λ
    - Can make λ vary randomly
  136. 136How is genetic/demographic uncertainty added into the model?By making λ smaller when the population size falls below a threshold
  137. 137How can we simulate catastrophes?By saying that λ is 0 with a probability of 0.01 - a one in a hundred year event
  138. 138What model does this produce at the end? How can we work out the probability that the population will go extinct over a particular timeframe?We have a stochastic (uncertain outcome) rather than a deterministic (certain outcome) model; if we run the model many time (>100, the more the better)
  139. 139When may ex-situ conservation become necessary?When populations are small and where the probability of extinction in the field exceeds the probability of survival
  140. 140What should take priority in situ or ex situ?CBD acknowledges that in situ should always be given priority and ex situ should be viewed as playing a supportive role to in situ conservation
  141. 141Ex situ is often used with ........, ...... species or with ........ species to conserve ........ diversityCharismatic; rare; agricultural; genetic
  142. 142What are some alternatives to storing seed in seed banks (as some lose viability in storage)? What about for those species that reproduce vegetatively?Pollen cryopreservation or freeze drying (doesn't account for females, however); tissue can be preserved in culture
  143. 143What are seed banks important for and give an exampleSeed banks are also vital to secure
    agricultural futures; Svalbard Global Seed Vault in the Arctic opened in February, 2008 and now houses >890,000 samples
  144. 144What happened to the Svalbard Global Seed Vault in May 2017?It was flooded after the permafrost melted - no seeds were lost but shows that it could be threatened by climate change
  145. 145What is the worldwide aim for the Millenium Seed Bank Project: Kew Gardens? How many species has it banked? How many reintroductions back into the wild have been carried out as a result of this?To safeguard 25% of the world's plant species by 2020; has already secured the future of ~all the UKs native flowering plants; 37,399 species have been banked (Oct. 2016); 420 reintroductions back into the wild
  146. 146What is WAZA?The World Association of Zoos and Aquariums - represents c. 300 institutions across the world; have a published conservation strategy; one of their objectives is to convince zoos and aquariums that their priority should be conservation
  147. 147How many species are Extinct in the Wild according to IUCN?69 (34 animals and 35 plants); some of these persist in zoos
  148. 148Do zoos prioritise threatened taxa?Not always; done quite biasedly; with primates a lot of the threatened species are held in captivity but for other groups like insects, rodents and amphibians the threatened species are much less represented in zoos
  149. 149How many species is it estimated that zoos will be able to protect?~1000
  150. 150What technologies does captive breeding use to promote breeding and prevention of inbreeding?Semen collection for artificial insemination; in vitro fertilisation (IVF); embryo transfer; cryopreservation (280 species currently); cloning? - allows population increase without collecting from the wild and can be used for re-introduction or population reinforcement
  151. 151Captive breeding played a role in the recovery of ..... out of 68 vertebrates whose threat level decreased (IUCN categories)17
  152. 152Why sort of books do captive breeding institutes keep and what are they used for?Stud books - detailed information kept on each species; used to facilitate animal transfers to minimise inbreeding and genetic drift
  153. 153What is a brief history or the black-footed ferret?- Once widespread in the prairies of
    N. America
    - 1950s: Severely impacted by government policy to eradicate prairie dogs and was thought to be extinct
    - 1981: A population of 130 discovered in Wyoming
    - 1985-87: The population became infected with canine distemper, so the remaining 18 animals were brought into captivity (declared EW by IUCN)
  154. 154How successful was the captive breeding program?-Led to >8000 births
    - 1991: reintroduction into 18 sites began
    - Only 3 populations thought to be self-sustaining
    - More than 2000 animals released
    - 2007: wild population estimated at 750 and is now ~1300
    - Now classed as EN rather than EW
  155. 155What was the impact of captivity on black-footed ferrets?Captive ferrets are 5-10% smaller than in the wild; they probably have compromised fitness in the field; males and female ferrets are of more similar size in captivity; the effect is not genetic –thought to be due to lack of mechanical stimuli in cages
  156. 156What can be said about the distribution and population size of the wart-biter?- Very localised in southern England since 1800 at least
    - Currently 5 naturally surviving populations (Sussex, Kent, Wiltshire)
    - Colonies range from 20 –2000 individuals
    - Vulnerable due to inappropriate grassland management
  157. 157What recent action have been done to try and help the wart-biters?- Captive breeding and reintroduction
    programme at the Centre for Invertebrate Conservation (London Zoo) funded by English Nature
    - Re-introduced population in Kent
    - Research into habitat requirements,
    population dynamics and formulation of
    management recommendations
    - All populations are in reserves (NNR, SSSI or CNT)
    - Species action plan been developed
  158. 158What are some of the problems with captive breeding?Initial source of stock can endanger wild pops.; expensive (needs lots of facilities); need large pops. to prevent genetic drift & loss of genetic diversity; captive pops. undergo selection; loss of learned behaviour; high density=disease susceptibility; animal welfare e.g.stress; getting species to breed is often difficult
  159. 159Why has the Sumatran rhino seen major declines?Habitat loss and poaching; there are 3 subspecies with ~300 rhinos in total
  160. 160What was done to try and help the species?- 1984-1996, 40 animals transported to zoos in SE Asia and the West
    - To date only four young born (in USA), three to one mother
  161. 161What is the impact of captivity on African and Asian elephants?African avg. life expectancy zoos: 16.9 yrs African avg. life expectancy wild: 56 yrs
    Asian avg. life expectancy zoos: 18.9 yrs
    Asian avg. life expectancy wild: 41.7 yrs
  162. 162What is the impact of captivity on mammals with larger range sizes in the wild?- Such mammals include: lions and polar bears
    - They higher infant mortality and higher incidence of stereotypical behaviour
  163. 163Give an example of genetic changes in animals in captivity- In Steelhead trout, reproductive capabilities decreased by ~40% per captive generation when returned to the wild
    - Probably due to the loss of natural selection and domestication selection
  164. 164Give an example of an animal showing problems on its release in the wildTasmanian devil - showed an increase in the probability of a fatal vehicle strike with increasing generations in captivity
  165. 165Give one way in which selection in captivity can be minimisedReducing the number of generations in captivity, achieved by:
    - Cryopreservation of germplasm
    - Delayed reproduction
  166. 166What's another way in which selection in captivity can be minimised?By fragmenting the populations as although subpopulations lose diversity through genetic drift, it may be safer and maintains between-population diversity; could transfer one animal every 1-2 generations to minimise inbreeding
  167. 167Of ..... published studies of reintroductions for conservation, only ......% were successful and .....% definite failures (likely publishing bias towards success) - as of 200087; 23; 25
  168. 168Reintroduction is likely to succeed if:1) The source population is wild
    2) A large number of individuals are released (some doubt by Pullin 2002)
    3) The cause of the original decline is removed

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(LEC242) BIOLOGY DEGREE LEVEL Fichas sobre LEC242 continued, creado por Anna Hollywood el 05/03/2018.
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Anna Hollywood
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