Invasives species PDF

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invasive species handout on lecture...

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Mammal diversity, behaviour and conservation INVASIVE SPECIES What is an invasive species? Introduced / non-native / exotic / alien / non-indigenous species = “a species living __________ its natural geographical range as a consequence of _________________” An invasive species = “a non-indigenous plant or animal that __________ affects its habitat __________ or economically” Naturalized species = “an introduced or invasive species that has been present for such a period of time as to become viewed as part of the natural ecosystem”

How do invasive species arise? Deliberate

Accidental

Livestock / Food Bio-control agents Companion animals Hunting quarry Aesthetic reasons Commensal rodents Shipwrecks Escapes from:-

Examples: _______________________ Examples: _______________________ Examples: _______________________ Examples: _______________________ Examples: _______________________ Examples: _______________________ Examples: _______________________ Agriculture: Goats, Pigs, Sheep Companion animals: cat, exotic pets Fur farms: American mink, coypu Zoos: Reeves’ muntjac Research labs: primates

British mammal fauna ____ are considered feral / non-native Deliberate Accidental

Livestock / Food Aesthetic / hunting Commensal rodents Escapes

Examples: _______________ Examples: _______________ Examples: _______________ Examples: _______________

Invasive mammals in conservation 1. Invasive species impacting mammals 2. _________________________________________________ Mammals impacted by invasive species Plant example:

_________________________________________________

Bird example:

_________________________________________________

Amphibian example:

_________________________________________________

Reptile example:

_________________________________________________

Mammal diversity, behaviour and conservation Impacts on other species Global Invasive Species Database Origin Livestock species Companion animals Commensal species Source of food and / or for sport-hunting Bio-control Furbearer Scientific purposes

Examples Cattle, donkey, goat, pig, sheep Dog, cat House mouse, Pacific rat, brown rat, black rat, musk shrew Rabbit, reindeer, red deer, Axis deer, white-tailed deer, red fox, rusa deer, brown hare Chilla, hedgehog, Indian mongoose, ferret, stoat, weasel American mink, Brush-tailed possum, coypu, beaver, snowshoe hare Patas monkey, rhesus macaque, crab-eating macaque

Impacts can occur at 5 different levels:

1. Individual 2. _______________ 3. Population 4. _______________ 5. Ecosystem

Examples of genetic impacts:

Scottish wildcat & domestic cat Red deer & _______________ Polecat & _______________

Examples of population impacts:

Predation: ___________________ Competition: ___________________ Disease: ___________________

Examples of community impacts:

Rabbit & red fox combined

Examples of ecosystem impacts:

Disruption of fire regimes Flooding Soil erosion

Case study: rabbits & red foxes Rabbit:

Burrowing bettong Rufous hare-wallaby ________________ Lesser stick-nest rat

Red fox:

Red-tailed phascogale Rock wallabies Quoll _______________

There is substantial interaction between rabbits and foxes that has exacerbated the impact of foxes. Known as ____________________

Mammal diversity, behaviour and conservation Hyper-predation:

California Channel Islands Macquarie Island

Feral pig–Golden eagle–Channel Island fox Rabbit - ____________ - Seabirds

_______________ = where one top predator suppresses abundance of lower predator, such that absence f top predator leads to increased abundance of lower predator Yellowstone Grey wolf – Coyote – Red fox Management of invasive species Prevent _______________ (requires quarantine & early detection surveillance) Reduce to an acceptable level Eradication Example: Rats & mice Method: Poisoning Rabbits, goats & pigs ____________________ Cats ____________________ _______________ Trapping Management issue 1: most expense incurred in _______________________________ Management issue 2: must be limited option for _______________________________

Management issue 3a: hyper-predation. Must control __________________________ Management issue 3b: meso-predator release. _______________________________ Management issue 4: wildlife management is a _______________________________...