FW104 1nd Edition Lecture 12 Outline of Last Lecture Outline of Current Lecture I. Wildlife Management, Disturbance & SuccessionA. Disturbance1. Disturbance Vary in Scalea. local b. regional2. Disturbance Vary in Intensity3. Disturbance Vary in Frequency 4. Role of Natural Disturbance B. Succession1. Seral Stagesa. Primary Succession b. Secondary Successionc. Stages of Succession ExplainedC. Anthropogenic Disturbance 1. Deforestation2. Light Pollution3. Sound PollutionThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Current LectureI. Wildlife Management, Disturbance & SuccessionA. Disturbance- an event that destroys or removes ecosystem components either naturally or human caused, usually followed by a recovery period called succession 1. Disturbance vary in scale- size of disturbancea. local: tree falls, animal burrow or wallowsb. regional: fires, floods, hurricanes, insect outbreaks2. Disturbance vary in intensity:- percent of the vegetation that the disturbance removes - Ex: low intensity fire destroys undergrowth, high intensity fire destroys the canopy.3. Disturbance vary in frequency: # of disturbances that occur in a time period - Ex: fire4. The role of natural disturbance: - often integral to biodiversity and ecosystem function- Ex: serotinous pine cones (need fire to open)B. Succession: - process of community development over time until a relatively stable stage is reached (climax community). Follows disturbance 1. Seral stages: - overlapping phases, sequence of species present at various times since disturbance- PIONEER STAGES: bare rock  lichens  small annual plants, lichens  perennial herbs, grasses.    INTERMEDIEATE STAGES: grasses, shrubs, shade tolerant trees.  CLIMAX STAGES or COMMUNITY: shade tolerant trees. a. Primary succession: - Succession occurring for the first time in previously uninhabitable sites, no true soilpresent. - Where might this occur? Volcanic islands in ocean, glacial retreat (glaciers melt which exposes areas with no soil). - Can take 1000s of yearsb. Secondary succession: - follows disturbance- soil is already there- more common than primary- take 100s of years c. Stages of Succession Explained: - Pioneer stage: lichens break apart rock to make soil, grasses, annual flowers, good colonizers, poor competitors, - Intermediate stage:- Climax community: shade-tolerate species, poor colonizers, good competitors, relatively stable (succession “stops” here) BUT climax community not always reached, frequent disturbances may maintain a system in earlier stages, successionas cyclical- Animals are part of succession too- Succession as management tool: Leopold’s tools = disturbances – axe, cow, fire, plowC. Anthropogenic disturbances - Impacts to wildlife and biodiversity. - Ex: deforestation, light pollution, noise pollution1. Deforestation- Tropical Rain Forests: 6-7% of earths land surface, yet have more than half the species in entire world, about half of tropical evergreen forests remain, some countrieshave lost over 90% of forest (Bangladesh, Madagascar, Ghana)- Brazilian Amazon Forest: 60-70% by cattle ranches, clearing pastures: cattle ranching is leading cause of deforestation in Brazilian Amazon, “hamburger connection”, shiftingsmall scale cultivation = small scale cultivation of crops by poor farmers, fires: slash& burn farming combined with drought, fires spreading into virgin forest, at least 10% of amazon destroyed by fire, policy in brazil that encourages people to spread into the forest if they there for 5 years it was their property. - Implications of deforestation: loss of biological diversity = loss of societal resources- Forest fragments not enough: widespread local extinctions in tropical forest remnants, Aug. 9, 2012 the small fragments of tropical forests left behind after forestation are suffering extensive species “extinction”, according to new research led by University of East Anglia- What is needed to lower deforestation: sustainable agriculture and forestry, international development assistance with ecological information, network of parks & reserves, use land already deforested for logging and grazing, ecotourism on remainingforests 2. Light pollution: introduction of artificial light, either directly or indirectly into the natural environment. - What are some common causes of light pollution? Urban areas, residential, street lights, industrial- Light pollution can affect navigation/migration, predator-prey interactions, behavior, sleep cycles- What can we do to reduce light pollution: direct light where it’s needed, shield residential/industrial lights3. Noise pollution: sound becomes unwanted when it either interferes with normal acitivties or diminishes one’s quality of life, unwanted or disturbing sounds. - Examples include: shipping noise, recreation, traffic noise, industrial noise- How does noise effect wildlife: interferes with communication, energy cost of changing vocalizations, avoidance of noise can cause habitat fragmentation, alters predator-prey relationships- Noise pollutions reducing includes noise interactions in sensitive habitat, noise mitigation, designate quiet areas, quiet