Chapter 9: Population Ecology: Distribution & Abundance

Question 1

 Population:A group of ___ of the same species that occupy a given ___ at a given ___ .

Answer 1

individuals
place
time

Question 2

 Local distribution – generally ___ , not ___ (which reflects patchy character of habitat, dispersal history, etc.)

Answer 2

patchy

continuous

Question 3

 Geographic distribution: the entire ___ ___

Answer 3

geographic range

Question 4

 Population size – the number of individuals in the ___

 Population density – the number of individuals per ___ ___

Answer 4

population

unit area

Question 5

 Relative Abundance:
 Most species are ___ and ___ restricted
 Deborah Rabinowitz identified 7 forms of ___

Answer 5

rare
geographically
rarity

Question 6

 Genets – single ___ individuals; best focus for ___ questions

Answer 6

genetic

evolutionary

Question 7

 Ramets – actually or potentially independent members of a genet; clones; best focus for how (semi-)independent ___ ___ compete

Answer 7

genet; clones

physiological units

Question 8

 Dynamics: Neither distributions nor abundances are ___

Answer 8

static

Question 9

 Dispersal Links Populations:

Answer 9

 Natal dispersal (dispersal outside of the birth spot); Other dispersal (among breeding sites, foraging patches, etc.); Migration

Question 10

 Distribution & Abundance are limited by

Answer 10

Habitat Suitability, History & Dispersal

Question 11

 Dispersion Patterns

Answer 11

 Clumped, random, regular (over-dispersed)

Question 12

 The pattern of dispersion is very often

Answer 12

scale-dependent.

Question 13

 D > 1: ___; Large variance
 D ~ 1: ___
 D < 1: ___; Small variance

Answer 13

Clumped
Random
Regular

Question 14

 Population abundances and distributions can be estimated with

Answer 14

area-based counts, distance methods, mark-recapture studies, and niche models.

Question 15

 Area-based counts – random or stratified random placement of many ___ ___, ___, or ___; (average count/area) * total area = population estimate

Answer 15

replicate plots, quadrats or transects

Question 16

 Distance methods – employ ___ ___ ___ (one for each species or habitat) to weight observations & calculate population estimates
 Line transact:
 Point sampling:

Answer 16

detection probability
walk along a straight line
stand in one place

Question 17

 M1 / N = R / M2

Answer 17

 M1 = # of individuals caught & marked on 1st occasion
 N = # of unknown individuals in the population
 R = # of marked individuals caught on 2nd occasion
 M2 = # of individuals caught on 2nd occasion

Question 18

 Ecological niche-modeling

 Ecological niche: the ___ and ___ conditions that the species needs to grow, survive, and reproduce

Answer 18

abiotic and biotic