Bio Invaders Final (shortened)

PCB2441 - UF Fall 2023 [socred a 94% on exam]

impact levels

GYPSY (GIP-CE)

1. genetic

2. individual

3. population

4. community

5. ecosystem

Genetic Level Impact

gene pool - hybridization, introgression

genetic level example

non-native Spartina and native Spartina interbreeding

individual level impact

behavior, morphology, demographic rates

individual level example

invasive ants changing behavior of mice

population level impact

population growth, composition

population level example

Burmese pythons reducing populations

community level impact

diversity, composition

community level example

• invasive plants affecting tick survival and host abundance

• Hemlock Woolly Adelgid reducing forest diversity

ecosystem level impact

material flow and operations

ecosystem level example

• Reed Canary Grass - hydrology

• Cogongrass - fire regime

• Morella Faya - nitrogen fixation

• Hemlock Woolly Adelgid - carbon storage, fish populations, nutrient flow, stream warming

methods to evaluate

1. Observation

2. Removal

3. Introduction

observation method

• invader v. invader-free areas

• shows broad patterns

• quick and easy

• hard to disentangle cause/effect

removal experiment method

• method determines result

• effects may not be removed

experimental introduction method

• under controlled conditions

• not realistic

• ethical concerns

possible interactions

1. additive (+)

2. synergistic (x)

3. offsetting (-)

inspection policy

• large cargo volume

• relies on exporting country

ineffective laws

• focus on agriculture

• uses dirty lists

• tight/competitive budgets

• often too late

inspection policy example

Microstegium - worst invader, not regulated

ineffective laws example

FIRFA 1947 - regulation of pesticides

biocontrol steps

Fast, Fried, Quick, P.R.E. (FF-Q-PRE)

1. Feasibility

2. Foreign Host Range

3. Quarantine

4. Permit for Release

5. Release and Establishment

6. Evaluations

biocontrol pros v. cons

PROS

• widespread invasions

CONS

• expensive

• many years

• cannot be contained

chemical/mechanical pro v. cons

PROS

• affordable for short-term

• quick

• targeted

CONS

• expensive for long-term

• controversial

• can be used improperly

• can fail

chemical method examples

• backpack sprayer

• airboat

• injections

• baits

mechanical method for plants examples

• cut stump

• dig + burn

• mowing

mechanical method for animals examples

• trapping

• fencing

• shooting

Blackburn Model

TIES-I

1. Transport

2. Introduction

3. Establishment

4. Spread

5. Impact

speciation

1. allopatric - gographic

2. sympatric - behavior

global drivers of biodiversity

ORID

1. old habitats

2. reinforcing

3. isolation

4. divided landscapes

continent v. island

• resistance: against disease/extinction

• persistence: somewhere else

ballast

soil, sand, rocks brings weeds and insects

traits of invasive animals

• fast growth rate

• high fecundity

• quick maturity

• toleration of conditions

• broad diet

• highly competitive

• few predators/disease

barriers of invasion

Billy Goes Camping, Spreading Red Dust Everywhere

BARRIERS

1. Geography

2. Captivity/Cultivation

3. Survival

4. Reproduction

5. Dispersal

6. Environment

traits of invasive plants

• fast growth rate

• high fecundity

• thrive under disturbed conditions

• habitat generalists

• extended phenology

• allelopathy

• alter soil conditions

inavsive mechanisms

1. propagule pressure

2. abiotic factors

3. biotic factors

propagule pressure

• size x frequency

• null hypothesis

abiotic factors

disturbance causes favorable conditions

biotic factors

• enemy release hypothesis

• biotic resistance