Conservation Bio Exam 2: Movement of Exotic Species

exotic

any species where it is living outside of its native range; synonymous with introduced, non indigenous and non native

naturalized

exotic species that sustain pops in a new habitat without human intervention

invasive

any species that is exotic and its pops are expanding rapidly in the new habitat

unintentional introductions of exotic species

stow-aways with humans, cargo, ballast (ship)

example of stow-away species

solenopsis invicta red imported fire ant; hitchhiked on human cargo

what are the modes of spread of exotic species in introduced habitat

jump-dispersal and diffusion dispersal

jump-dispersal

dispersal to a new geographic area without occupation of the intervening region

diffusion dispersal

continuous dispersal along an invasion front

list of intentional introductions of exotic species

subsistence and commerce, recreation, aesthetics, biologival control, scientific investigations

example of species introduced for recreational purposes

many fish species

classical biological control

technique for controlling populations of an invasive exotic species by introducing another exotic species that is a natural enemy of the exotic pest

examples of classical biological control technique

r. conicus acting on musk thistle phyllaries

enemy release hypothesis

invasiveness of some exotic species results from decreased predation in the invaded range because co-evolved predators are not present in the invaded range

example of enemy release hypothesis

invasive lespedeza cuneata and native lespedeza capitata

geographic movement of exotic plants

leveraging human infrastructure and dispersal forces to expand along environmental corridors, into cooler regions as climates warm while favoring disturbed, nutrient-rich lowlands.