EOSC 474- Biological pollution

control cons

heavy cost in money and time usually have complications

control

mechanical control- time consuming and costly chemical- hazard for environment biological-often leads to further complications

Consequences: species "ecological roulette"

-outcomes unpredictable -a complex combination of factors result in invasion (species based--> anatomy/features, environmental based, species interaction based--> interaction with other species)

Secondary introduction (regional spread)

-recreational boating -research and teaching -natural dispersal

Why do some species do well?

1) Enemy-release hypothesis 2) Evolution of increased competitive Ability (EICA) 3) Invasive meltdown

what are the impacts of biological pollution?

1) Environmental. 2) Economic. 3) Social. 4) Human Health.

Management

1) Prevention 2) Control 3) Eradication

how do ships contribute to distributing invasive species?

1) ballast water: -used for stability and trim -dry ballast-terrestrial invasions prior to 1900s -benthic and planktonic organisms ->150,000 tonnes/ship 2) Ballast sediment: -zooplankton & phytoplankton resting stages -survive adverse conditions, desiccation, -survival from days to years -can hatch in dark conditions 3) Hull Fouling: -Sessile or sedentary organisms -spawn or release on arrival -increased speed, shorter port visits may have decreased opportunities -ban of Tributyltin (TBT) increased hull fouling

Prevention

1) best method available 2) least costly Predicting invasions: difficult task vector management (legislation and regulations, customer inspections, best practices).

list the 3 stages of invasion

1) human-mediated movement 2) spread 3) impact

Invasion meltdown: what are some consequences of facilitated spread by other invasive species.

1) resident populations disrupted 2) habitat alteration

eradication cons

difficult and costly often not useful in marine environments

Exotic species

a species that has been introduced from the geographic region where it evolved to an area outside its natural range.

Environmental impacts:

a) Resource competition: compete for shelter, substrate, nutrients, food, light, space, etc. b) predation: Introduced species can be superior predators on native species. No co-evolution of predator/prey "arms-race" c) Biodiversity loss d) altered ecosystem structure and function.

Invasive species

an exotic species that spreads causing either economic, health, or ecosystem harm. example: a plant that sreads and alters the composition, structure and workings of the natural ecosystems in which it spreads.

Prevention pros

best method available least costly

Control pros

results immediate

eradication pros

results immediate

Aquarium/live fish trade/research

-intentional or unintentional release

How does boating contribute to distributing invasive species

-Hull fouling -Entanglement -Bilge tanks -Live bait

commercial shipping

-ballast water -ballast sediments -hull fouling

vectors and pathways: natural

-changing climatic conditions -extreme weather events -removal of barriers -hitchhiking with migratory animals

human-mediated pathways

-commercial shipping -recreational boating -aquaculture trade -live fish and aquarium trade -research and teaching

Primary introduction

-commercial shipping -aquaculture -live trade

vectors and pathways: Anthropogenic (human mediated)

-eliminates geographical barriers of species and gene flow -due to increased trading and globalization -accidental or intentional

Economic impacts both direct and indirect?

-estimated economic harm in BC, Canada for 18 species- $13.3-34.5 billion/year -$137 billion/year in US -Invisible taxes (reduced yield) -can be both positive or negative. ie. pacific oyster, manila clam, softshell clam have become commercial species.

Eradixation

-extremely difficult and costly to implement in marine due to open nature of water bodies -limited number of examples

Whys is global human population growth increasing resource use?

-habitat destruction -over-harvesting -climate change -chemical & nutrient application -biological pollution

Aquaculture

-hitchhikers -intentional release

Recreational boating

-hull fouling -entanglement -bilge tanks -live bait

Enemy-release hypothesis

Absence of native predators (will control the numbers), competitors, parasites and disease. "an area with no predators will allow the species to have more energy to reproduce"

what are some synonyms for invasive species?

Alien, pest, non-indigenous, foreign, neophyte, import

What conditions help to prevent invasions?

Biotic Resistance (antagonistic): Species-rich communities may be more resistant to invasion because of: -limiting resources -more native competitors and predators Environmental condition: steno-species (is a species or living organism only capable of living or surviving within a narrow temperature range) are bad invaders (stenothermal, stenophagous, etc)

Human health impact directly or indirectly

Cholera epidemic (Vibrio cholerae)

prevention cons

Difficult to predict factors enforcing regulations

Invasion meltdown-direct facilitation:

Effects that directly benefit another invader (ex: more nutrients, shelter).

Invasion meltdown-indirect facilitation:

Effects that reduce an invader's enemies or enhance its prey.

Naturized species:

Exotic species that are able to reproduce in the new environment (don't cause harm to other species).

Evolution of increased competitive ability (EICA)

Reallocation of resources in new range. because of a lack of native predators, scientists reasoned, introduced introduced organisms are able to reallocate resources from defense mechanisms into growth and development. Example: Introduced plants can thereby evolve to grow taller, produce more biomass, and yield more viable offspring than their native counterparts, according to the hypothesis.

what are the two types of introduction?

Regional spread and inter-regional spread

Biological pollution

The effects of introduced, invasive species sufficient to disturb an individual (internal biological pollution by parasites or pathogens), a population (by genetical change) or a community (by increasing or decreasing the species complement); including the production of adverse economic consequences.

Looking at the big picture and considering the trends in biological pollution, should we (scientists, institutions, government agencies, interested parties) spend time and effort to fight invasions? List all the CONS

• Costly • Loss of biodiversity, has impacts on human health and detrimental economical impacts. • Control of invasion can lead to hazards for the environment if chemicals are used • Prevention may require new legislation that had to be enforced and adopted by the population to be effective • Leads to habitat alteration which could promote further invasive species to naturalize to the area further exacerbating the problem • Eradication is extremely difficult to implement in marine environment due to open water • Mechanical control of the invasion is time consuming and also costly • Can introduce diseases and parasites to local populations Limit potential of a habitat, if the invasive species can be beneficial

Looking at the big picture and considering the trends in biological pollution, should we (scientists, institutions, government agencies, interested parties) spend time and effort to fight invasions? List all the PROS

• Preventative measures are less costly • Conserves biodiversity • Biological control often leads to additional complications • Reduces the potential damage to the ecosystem due to the invasive species • The results of control and eradication can be immediate • Removal of invasive species can ensure the health of local fisheries