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 speciesEcosystem A Ecosystem B
4 oak species 3 oak species
bl oak = 40 bl oak = 120
wh oak = 30 wh oak = 60
r oak = 20 r oak = 20
pin oak = 10 pin oak = 0
A = B = alpha () diversity – within habitatC = beta () diversity – among habitatD = gamma () diversity – geographic scale
Three Scales of Diversity
Alpha & Gamma Species Diversity Indices
• Shannon-Wiener Index – most used
- sensitive to change in status of rare species
s
iii ppH
1
))(ln('
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
s
iii ppH
1
))(ln('
Alpha & Gamma Species Diversity Indices
• Simpson Index – sensitive to changes in most abundant species
s
iipD
1
2)(1
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
s
iipD
1
2)(1
Alpha & Gamma Species Diversity Indices
• Species Evenness
max'
'
H
HJ
H’max = maximum value of H’ = ln(s)
Beta Species Diversity Indices• Sorensen’s Coefficient of Community
Similarity – weights species in common
cba
aSS
2
2
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 / 2a + b + c
Or 1.0 - Ss
Species Sample 1 Sample 2
1 1 1
2 1 0
3 1 1
4 0 0
5 1 1
6 0 0
7 0 0
8 1 0
9 1 1
10 0 0
11 1 1
12 0 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
Territorial (Spot) Mapping
Limitations:- territorial species (grouse, songbirds)- sex ratio known or
assumed-nonterritorial males? (floaters)-ability to id species & map territories
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 AbundanceIndices 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 AbundanceIndices of Relative Abundance
Capture TechniquesCapture Techniques
Capture TechniquesCapture Techniques
Radio Telemetry
Female
Male
Spatial Organization
Scent Stations
Remote Camera Systems
DNA Fingerprinting
GPS
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