Biodiversity Why is Biodiversity Important Genetic diversity Why
Biodiversity
Why is Biodiversity Important? • Genetic diversity:
Why is Biodiversity Important? • Species Diversity:
Why is Biodiversity Important? • Ecosystem Diversity:
Diversity = Richness + Evenness • richness: count of # species • evenness: relative abundance of species Ecosystem A Ecosystem B 4 oak species 3 oak species bl oak = 40 wh oak = 30 r oak = 20 pin oak = 10 bl oak = 120 wh oak = 60 r oak = 20 pin oak = 0
Three Scales of Diversity A = B = alpha ( ) diversity – within habitat C = beta ( ) diversity – among habitat D = gamma ( ) diversity – geographic scale
Alpha & Gamma Species Diversity Indices • Shannon-Wiener Index – most used - sensitive to change in status of rare species H’ = diversity of species (range 0 -1+) s = # of species pi = proportion of total sample belonging to ith species
Alpha & Gamma Species Diversity Indices • Shannon-Wiener Index
Alpha & Gamma Species Diversity Indices • Simpson Index – sensitive to changes in most abundant species D = diversity of species (range 0 -1) s = # of species pi = proportion of total sample belonging to ith species
Alpha & Gamma Species Diversity Indices • Simpson Index
Alpha & Gamma Species Diversity Indices • Species Evenness H’max = maximum value of H’ = ln(s)
Beta Species Diversity Indices • Sorensen’s Coefficient of Community Similarity – weights species in common Ss = coefficient of similarity (range 0 -1) a = # species common to both samples b = # species in sample 1 c = # species in sample 2
Beta Species Diversity Indices • Sorensen’s Coefficient of Community Similarity Dissimilarity = DS = b + c / 2 a + b + c Or 1. 0 - Ss
Species 1 2 3 4 5 6 7 8 9 10 11 12 Sample 1 1 0 1 0 0 1 1 0 Sample 2 1 0 1 0 0 0 1 0
Sorensen’s Coefficient • Sample 1 – Total occurrences = b = 7 - # joint occurrences = a = 5 • Sample 2 – Total occurrences = c = 5 - # joint occurrences = a = 5 • Ss = 2 * 5 / 10 + 7 + 5 = 0. 45 (45%) • Ds = 1 – 0. 45 = 0. 55 (55%)
Species-of-the-Week American woodcock (Scolopax minor)
Habitat • Woods & thickets with moist soil, small openings near woody cover • aspen, alder, willow cover types (early successional = seedling/sapling stage; <3 in dbh)
Food • Diet = 50 -90% earthworms • Diurnal foraging in spring/summer • Nocturnal foraging in winter • Long bill used as probe (foot stomping)
Reproduction Courtship behavior = males on breeding fields Mar. Apr -- polygynous Clutch size = ~4 eggs I. P. = 21 days; near full grown in 28 days Behavior - Migratory – winters in SE U. S. - Nonvocal calls = wing position
Estimating Abundance of Wildlife • Terms - Population - Relative vs. Absolute Abundance - Parameter vs. Statistic - Population Index - Accuracy - Precision - Bias
Estimating Abundance of Wildlife • Complete Counts (Census) - open habitat = visible wildlife - concentration of activity - small study area
Estimating Abundance of Wildlife • Complete Counts (Census) - Drives * Biased (under- or overestimate) - Territorial (Spot) Mapping e. g. , breeding birds
Limitations: - territorial species (grouse, songbirds) - sex ratio known or assumed -nonterritorial males? (floaters) -ability to id species & map territories Territorial (Spot) Mapping
Estimating Abundance of Wildlife • Complete Counts (Census) - Aerial Counts & Sensing - must see animal to count it! - Aerial Photos or IR Thermal Scans - photos of migratory waterfowl
Estimating Abundance of Wildlife • Complete Counts (Census) - Aerial Counts & Sensing • Aerial line-transect counts - must see animal to count it! • Aerial Photos or IR Thermal Scans - photos of migratory waterfowl - IR scans of wildlife (bowhunting study in MN – loss rate)
Estimating Abundance of Wildlife • Complete Counts - Sample Plots - Line transects (ground or aerial) - e. g. , flush count for grassland birds - assumes 100% detection
Indices of Relative Abundance • …dependent on the collection of samples that represent some relatively constant but unknown population size – Traps, number of fecal pellets, vocalization frequency, pelt records, catch/unit effort, number of artifacts, questionnaires, cover, feeding capacity, roadside counts
Indices of Relative Abundance
Capture Techniques
Capture Techniques
Radio Telemetry
Spatial Organization Female Male
Scent Stations
Remote Camera Systems
DNA Fingerprinting
GPS
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