Chapter 4: Abundance Flashcards
1
Q
population
A
a collection of individuals of a species in a defined area, for which it is meaningful to refer to abundances, birth and death rates, sex ratios, and age structure
2
Q
BIDE equation
A
Nt+1 = Nt + Bt + It - Dt - Et
3
Q
density
A
if abundance is scaled per unit area
4
Q
incomplete detection
A
since we cannot count them all, we have to deal with it
5
Q
estimate of abundance variable
A
N
6
Q
estimate of abundance formula
A
N = count / p
7
Q
census
A
complete count
8
Q
the value of p is often
A
< 1
9
Q
indices
A
- not sampling actual animals
- cannot estimate p
10
Q
indices: to rely on for abundance
A
known relationship between index and abundance
11
Q
indices: to rely on for trend
A
constant relationship between index and abundance
12
Q
transect methods
A
count animals along a line
13
Q
types of transect methods
A
- distance sampling
- replicated counts
- viewshed methods
14
Q
distance sampling
A
- p decreases with distance
- detection function can be estimated
15
Q
key assumptions of distance sampling
A
- all animals directly on the line are seen
- animals are counted only once and do not move before being sighted
- perpendicular distances are measured exactly
