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Invasive Species. Monday, March 14 th , 2011. Invasive species. “ non-native (or alien) to the ecosystem under consideration and whose introduction causes or is likely to cause economic or environmental harm or harm to human health .” Non-native Introduced via vector
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Invasive Species Monday, March 14th, 2011
Invasive species • “non-native (or alien) to the ecosystem under consideration and whose introduction causes or is likely to cause economic or environmental harm or harm to human health.” • Non-native • Introduced via vector • Established populations • Harm caused
Invasive species • A disturbance may be required to allow a population to go from an invading propagule to a locally sustaining population • Chinese Mitten Crabs • Damaged ecosystems more susceptible to invasion • 1998 bleaching event killed 80-90% of the coral reefs in the Seychelles, leaving them more vulnerable to invasions (IUCN.org) • 3 out of 330 spp. were introduced
Hot spots In areas subjected to the worst pollution, the most intensive fisheries and bottom trawling, and major shipping routes http://maps.grida.no/go/graphic/invasive-species-in-the-marine-environment-problem-regions
In 1999, it was estimated that the total cost of managing invasive species in the United States was around $120 billion per year (Pimentel et al. 2004)
Characteristics of successful invaders • Large home range • Ecological generalists • High invasion frequency • High larvae dispersal
Marine Fish invaders • Rare • <30 of 550 fish introductions in US were marine • Most introductions were intentional • Improvement to ecosystem? • Few negative effects actually documented
How did they get here? • Ballast water • Aquaculture • Seafood trade • Pet trade
Major pathways of marine invasive species infestation Maps.grida.no
Ballast Water Zebra mussel (Dreissena polymorpha) -Native to Eurasia -First sighted in 1988 in Great Lakes -Hudson River in 1991 -Now occur in densities as high as 700,000 per m2
Aquaculture • Rearing aquatic animals or cultivating aquatic plants for food • Animals can escape • Asian Carp • Atlantic salmon Drgeorgpe.com
Seafood trade • Intentional or Accidental • Chinese mitten crab (Eriocheir sinensis) • northern snakehead fish (Channaargus) Sportsmanhabitat.com
Pet trade • Escape or release of pets • Also feed, plants • “Don’t free Nemo”
Impacts of invasives • Foodweb interactions • Competition • Disease • parasites • Loss of biodiversity
What can be done? • “bounty” for fish capture • Volunteer surveys, Rapid Assessment surveys • Utilize invasive as food source • Biocontrol?
Education • http://www.iiseagrant.org/NabInvader/
Example 1: 2 invasive crabs • Carcinusmaenas • European shore crab Rough map of the distribution of Carcinusmaenas. Blue areas are the native range; red areas are the introduced or invasive range; and green areas are the potential range of the species.
Example 2: Sea lampreyPetromyzonmarinus • Life history: • Anadramous • Native to Atlantic coast
Example 2: Sea lampreyPetromyzonmarinus • Introduction: • Welland Canal • 1st spotted in Lake Eerie 1921
Example 2: Sea lampreyPetromyzonmarinus • Spread Dnr.wi.gov
Example 2: Sea lampreyPetromyzonmarinus • Impacts: • Affected sportfish • Disrupted foodwebs • One adult lamprey can consume 40 lbs of fish in its lifetime Dnr.wi.gov
Example 2: Sea lampreyPetromyzonmarinus • Response efforts • Lampricide • Physical barriers • Sterile male release Syracuse.com Fws.gov *90% reduction in most areas where these methods are applied
Example 3: LionfishPteroisvolitans • Background: • Venomous • Dorsal, anal, and pelvic spines • Native to Indian and W. Pacific oceans
Example 3: LionfishPteroisvolitans • Introduction: • Biscayne Bay, FL • Hurricane Andrew, 1992
Evidence for the aquarium trade as the vector for the introduction of lionfish ● Lionfish are popular in the North American aquarium trade ● Lionfish were released from an aquarium in Florida waters ● Other marine aquarium fish have been introduced in Florida waters ● Color patterns of lionfish off the SE US are similar to those from the Philippines where many are collected for the aquarium trade ● No successful introductions of scorpaenids are known to have occurred via ballast water ● In more than a century, no Pacific marine fish are known to have been introduced into the western Atlantic Ocean via ballast water Coastalscience.noaa.gov Oceanservice.noaa.gov
Example 3: LionfishPteroisvolitans • Spread: • Long distance larvae dispersal • Females release large egg masses, fertilized externally, gradually break apart to release larvae • Some lionfish reproducing every few days • No natural enemies
Example 3: LionfishPteroisvolitans • Impacts • Affecting food web, no natural predators in Atlantic Ocean Pacific Cornetfish, Fistulariacorneta (Mexicofish.com)
Example 3: LionfishPteroisvolitans • Response efforts • Bounty • Research • Outreach, Education