Chap 11

Question 1

In order to determine whether a species is in need of protection we must first ask….

Answer 1

whether the species is in immediate risk of extinction

Question 2

in order to answer whether the species is in immediate risk of extinction we must have….

Answer 2

an estimate of population size

and then ask whether the population is increasing, stable, or declining

Question 3

Gathering existing information about a species prior to….

Answer 3

listing is essential

Question 4

Information comes from:

Answer 4

1. published literature

2. Unpublished literature

Question 5

published literature

Answer 5

often compiled using search engines like Thomson Reuters Web of Science or Google Scholar

Question 6

unpublished literature

Answer 6

consists of reports issued by scientists enthusiastic citizens, government agencies, and conservation organizations

Question 7

Once the natural history and likely geographic distribution of a species is understood……

Answer 7

fieldwork is conducted to gather data specific to conservation needs

Question 8

Gathering background information

Answer 8

vast majority of world’s species not well studied

ecology of a species often changes from place to place

Usually the most expensive part of gathering information

Question 9

species of concern must be….

Answer 9

surveyed in the field and monitored over time

Question 10

Surveys are often termed

Answer 10

inventory and monitoring (I&M)

Question 11

three most common approaches to I&M

Answer 11

1. Censuses
2. Surveys
3. Demographic studies

Question 12

Census

Answer 12

count of the number of individuals in a population

Question 13

Census can only be used on species that:

Answer 13

1. don’t move much
2. are east to detect
3. have a limited distribution

Question 14

Survey

Answer 14

repeatable sampling method to estimate the abundance or density of a population or species

Question 15

In survey’s ranges…..

Answer 15

can be divided into sampling segments and individuals in certain segments counted

can then estimate actual population size

Question 16

Demographic studies

Answer 16

follow known individuals of different ages and sizes in a population to determine their rates of growth, reproduction, and survival

Question 17

Mark-recapture

Answer 17

a method used to estimate population size by capturing, marking, releasing, then subsequently recapturing marked individuals

Question 18

mark-recapture assumes….

Answer 18

the proportion of individuals marked during the first sampling period is equal to the proportion of recaptured individuals in the second sampling

technique used to mark individuals depends on the organism

Question 19

The challenge of estimating trends

Answer 19

assuming a population based on a series of 2 or 3 points may be misleading

populations can fluctuate because of sampling error or from year-to-year population fluctuations that are not indicative of an overall population trend

Question 20

The discrete time model of exponential change can be written as:

Answer 20

Nt+1= lambadaNt –> lambada= (Nt+1)/Nt

Where N is equal to the population size at time t and lambada is the population growth rate

Question 21

lambada= (Nt+1)/Nt

Answer 21

if lambada= 1, the population is stable
if lambada> 1, the population is growing
if lambada < 1, the population is declining

Question 22

lambada= (Nt+1)/Nt

Assumptions

Answer 22

the population shrinks or grows at a constant rate, no matter how big the population becomes

There is no environments or demographic stochasticity

There is no movement of individuals into or out of the population, except through births and deaths

Question 23

lambada= (Nt+1)/Nt

Assumptions corrections

Answer 23

We can correct for some of these assumptions, by accounting for random fluctuations in growth rate across time periods

Question 24

A population will change at a rate equal to the _______ of lambada

Answer 24

geometric mean

Question 25

geometric mean

Answer 25

GM= square root (∏λ) Where ∏ indicates the product of λ across time periods

Question 26

Population viability analysis (PVA)

Answer 26

combines current population size (N), trend in populations size (λ), year-to-year variability in population growth rates to quantify the probability of extinction within some specified time frame

Question 27

PVA

Answer 27

one of the core technical tools used in the species approach to conservation

Question 28

By simulating population growth researchers.....

Answer 28

can project population size into the future for various time periods stochastic events can then be built into the model results is a range of population sizes that reflect what might happen in real world circumstances