Lecture 20 - Sampling 2

Question 1

surveillance

Answer 1

a process for monitoring insect related factors such as crop invasion, feeding, reproduction, dispersion, etc to get information on things like population density and dispersion

Question 2

2 types of surveillance

Answer 2

qualitative and quantitative

Question 3

qualitative surveillance

Answer 3

• less complex
• rarely produce eact numbers
• result in list of pests
• usually only an approximation or subjective measure of density

Question 4

quantitative surveillance

Answer 4

• more common
• numerically defines size of population
• examines numbers relative to space and time
• info is for guiding management decisions
• based around sampling

Question 5

sample

Answer 5

a group of sampling units taken from the population

Question 6

sampling unit

Answer 6

the proportion of the habitable space that you will draw your insects from

Question 7

sample size is a function of __________

Answer 7

population size

Question 8

sampling universe

Answer 8

the habitat in which the population occurs

Question 9

sampling technique

Answer 9

the methods used to collect the insects or information

Question 10

sampling program

Answer 10

the procedure for how you will employ the sampling technique (insect stage, # of samples, pattern, timing)

Question 11

2 types of sampling programs

Answer 11

extensive
intensive

Question 12

extensive sampling program

Answer 12

conducted over large areas and are generally intended to determine how species are distributed or to generate info on factors such as most damaging life-history stage

Question 13

intensive sampling programs

Answer 13

frequent, covers small area, high precision (for research use mostly)

Question 14

3 types of sampling methods

Answer 14

random
systematic
stratified

Question 15

random sampling method

Answer 15

randomly choosing sample locations and times

Question 16

systematic sampling method

Answer 16

samples are taken at fixed, pre-determined intervals but from a randomly chosen starting point

Question 17

stratified sampling method

Answer 17

samples are chosen randomly from diff categories called strata

Question 18

methods of sampling

Answer 18

absolute
relative
population index

Question 19

absolute method

Answer 19

estimate density from a precise area and compared based on area (typically uses nets or suction devices)

Question 20

relative methods

Answer 20

estimate density with only limited attention to area sampled and used to compare amoung studies based on effort (use traps)

Question 21

population index

Answer 21

measures product or effect of a population

Question 22

ways to accomplish better precision

Answer 22

variable intensity sampling
fixed number sampling
sequential sampling

Question 23

variable intensity sampliing

Answer 23

a mix of the properties of a fixed sample size and a sequential sampling plan

Question 24

fixed number sampling plan

Answer 24

a plan with a predetermined number of samples to be collected with level of accuracy chosen in advance

Question 25

sequential sampling

Answer 25

no prior knowledge of density is required and a number of samples collected is limited to the number required to make an appropriate decision

Question 26

benefits of sequential sampling

Answer 26

- reliable estimates generated quickly - can integrate info like field/plant distribution, optimal # of samples, level of tolerance, etc)

Question 27

sequential sampling plans typically use ___________

Answer 27

stop lines

Question 28

what do stop lines in sequential sampling tell you

Answer 28

between lines mean continue sampling below mean no damage and no managment needed above mean damage occuring and manangement is needed

Question 29

sampling techniques

Answer 29

- in situ (direct counts) - knockdown (insect knocked off plant and counted) - netting (insect caught in net are counted) - traps

Question 30

pros and cons of traps

Answer 30

pros - less time spent sampling - can be used for long periods - no need to count right away cons - can be costly - more subject to weather - animals - delay between answer and sampling