Transcript Complete Counts

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
s
H '   ( pi )(ln pi )
i 1
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
H '   ( pi )(ln pi )
i 1
Alpha & Gamma Species
Diversity Indices
• Simpson Index – sensitive to changes
in most abundant species
s
D  1   ( pi )
2
i 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
D  1   ( pi )
i 1
2
Alpha & Gamma Species
Diversity Indices
• Species Evenness
H'
J
H 'max
H’max = maximum value of H’ = ln(s)
Beta Species Diversity Indices
• Sorensen’s Coefficient of Community
Similarity – weights species in
2a
common
S 
S
2a  b  c
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
1
2
3
4
5
6
7
8
9
10
11
12
Sample 1
1
1
1
0
1
0
0
1
1
0
1
0
Sample 2
1
0
1
0
1
0
0
0
1
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 MarApr -- 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