Lecture 17

Question 1

are all alien species invasive?

Answer 1

no

Question 2

invasive alien species?

Answer 2

harmful alien species whose introduction or spread threatens the envr, the economy, or society, including human health

Question 3

what threats do invasive alien species pose?

Answer 3

envr

economic

societal & human health

Question 4

what envr threats do invasive alien species pose?

Answer 4

biodiversity & ecosys function

Question 5

what economic threats do invasive alien species pose?

Answer 5

invasive alien weeds

dutch elm disease

Question 6

what societal & human health threats do invasive alien species pose?

Answer 6

asian tiger mosquito can transmit yellow fever

west nile virus

Question 7

how have routes of species emigration changed?

Answer 7

Interchanged with other continents & areas is much faster & more common today

Question 8

enemy release hypothesis

Answer 8

invasive are free from predators & pathogens in the new area –> classical biological control

no adaptations from other organisms to control pop

Question 9

invasional meltdown hypothesis

Answer 9

a group of alien species facilitate one another’s invasion, increasing the likelihood of ecological impact

Several species come together to a new origin

need to have a variety of species to support their food web

Question 10

utilization of new niches

Answer 10

no competitors

Question 11

why do some alien species become invasive? (3)

Answer 11

enemy release hypothesis

invasional meltdown hypothesis

utilization of new niches

Question 12

what is an ex of a pest utilizing a new niche? & what is the result?

Answer 12

eathworm in NA

Have completely modified the soil ecosystems

Question 13

describe how classical BC was used in cottony-cushion scale

Answer 13

almost destroyed citrus industry

vedalia ladybeetle was introduced

cottony-cushion scale was almost extinct

brought many other ladybeetles that they thought would solve the same prob but it didn’t & is why we have so many ladybeetles today

Question 14

describe the soybean aphid lifecycle

Answer 14

Summer – all females (asexual reproduction) in soybeans

Fall - migrate out of soybeans, move to buckthorn to sexually reproduce & lay eggs

Spring - female without eggs, have several gens until nutrition is at a max then reproduce aphids with wings that go to the soybean fields in the summer

Question 15

what stage in the soybean aphid lifecycle do the aphids exponentially increase their pop?

Answer 15

summer - during asexual reproduction

Question 16

what components of the soybean aphid lifecycle is introduced?

Answer 16

all of it! aphid, soybean & buckthorn

Question 17

what is the overwintering host of soybean aphids?

Answer 17

buckthorn

Question 18

what is the summer host of soybean aphids?

Answer 18

soybean

Question 19

what are the native species in the soybean aphid sys? (2)

Answer 19

Lysiphlebus testaceipes

Minute pirate bug

Question 20

the invasion of aphids has led to what adaptation?

Answer 20

incres abundance of exotic ladybeetles

decres abundance of native ladybeetles

Question 21

describe the diets of gypsy moths & what does it result in?

Answer 21

polypagous - don’t need to feed on a particular tree

enables rapid spreading

Question 22

the pop fluctuations of gypsy moths are due to:

Answer 22

NPV virus (high densities) - causes pop to crash

rodents (low densities)

Question 23

describe the lifecycle of gypsy moths

Answer 23

Eggs in September – May

6 instars in May – July

Pupae in July – August

Adults in August – September

Question 24

what is the origin of gyspy moths?

Answer 24

europe

Question 25

how were gypsy moths introduced?

Answer 25

by an amateur entomologist, escaped his home

Question 26

how do gypsy moths spread?

Answer 26

slowly, females are almost flightless

but produce a lot of larvae making them prolific

Question 27

what was the physical control response to the gypsy moth invasion? (4)

Answer 27

egg mass destruction

Burlap bands for catepillars

spray programs (DDT in defoliated areas)

synthetic insecticides - broad spectrum

Question 28

what was the biological control response to the gypsy moth invasion? (5)

Answer 28

Parasites, pathogens

Btk sprays (microbial pesticide)

NPV (nuclear polyhedrosis virus)

Quarantine, inspection, monitoring
Main solution is to quarantine to provide spreading

Insecticides to eradicate from new areas

Question 29

describe how the emerald ash borer infects

Answer 29

Lays eggs in bark

larvae begin to make tunnels that disrupt phloem (can’t really detect them)

Don’t disperse too much, attack the same tree over & over - pop will grow slowly over gens

Question 30

what was the response of control of the emerald ash borer?

Answer 30

Banned movement of firewood & destruction of infested trees

10km-wide Ash tree-free zone

firewood movement ban infested tree destruction

Question 31

describe early detection of the emerald ash borer

Answer 31

done through branch sampling

done with visual or chemically baited trees

can only inject insecticides into a healthy tree

Question 32

what does a prevention strategy consist of?

Answer 32

early detection

rapid response

eradication, contaimnet & control

Question 33

what does early detection prevention consist of?

Answer 33

Surveillance & monitoring in high risk areas

Diagnostic capabilities to recognize alien species

Question 34

what does rapid response prevention consist of?

Answer 34

Plans & funds in place for a control scheme to prevent est

Education to garner public support for control measures

Question 35

what does Eradication, containment & control

prevention consist of?

Answer 35

Physical, chemical, biological & integrated strategies, quarantine measures etc.

Question 36

what 3 species of pests are thought to have come in wooden packing material such as pellets?

Answer 36

emerald ash borer

brown spruce longhorn beetle

asian longhorned beetle