8/6/2019 Biology 3709 - Alien Invasive Species
http://slidepdf.com/reader/full/biology-3709-alien-invasive-species 1/14
Alien
InvasiveSpecies
Matthew&
Zack
8/6/2019 Biology 3709 - Alien Invasive Species
http://slidepdf.com/reader/full/biology-3709-alien-invasive-species 2/14
� Non-native microorganisms, plants andanimals which adversely affect the areas they
invade. Debate on what actually constitutes a native species.
General agreement that a native species has fullyadapted to an areas natural environment.
� They do not always have negative effects.
May simply have invasive species livingpeacefully in a new environment.
Sometimes defined as an exotic species.
8/6/2019 Biology 3709 - Alien Invasive Species
http://slidepdf.com/reader/full/biology-3709-alien-invasive-species 3/14
� Can be stowaways on any transport vesseland get dropped off in f oreign territory.
� They can be intenti
onally intr
oduced byprivate companies.
� Can be unintentionally shipped on freshproduce or other exotic resources.
� Man made canals and other alterations to theenvironment can open up opportunities f ororganisms to invade new areas.
� Animal vectors are also common, such as
migrating birds.
8/6/2019 Biology 3709 - Alien Invasive Species
http://slidepdf.com/reader/full/biology-3709-alien-invasive-species 4/14
� They lack natural predators.
� They can introduce f oreign pathogens and
wipe out native species.� They can easily out-compete native species
f or resources and space. Native species have no built-in mechanisms to deal with
invasive species.
� Have high reproduction rates and can thrivein different environments.
8/6/2019 Biology 3709 - Alien Invasive Species
http://slidepdf.com/reader/full/biology-3709-alien-invasive-species 5/14
� They easily disrupt f ood webs (e.g. outcompetition).� They can f orm hybrids with native species,
ultimately causing lo
sso
f the native species.� They are huge economic antagonists, which take
lots of time and money to regulate.
E.g. zebra mussels costs ~$100 million/year to regulate
due to
damage to
ships, pipelines, and aquaculture.
8/6/2019 Biology 3709 - Alien Invasive Species
http://slidepdf.com/reader/full/biology-3709-alien-invasive-species 6/14
� Since the island of Newf oundland is
completely surrounded by ocean, any species
which migrate here (non aided by humans)must be able to tolerate salt water or cross by
air/ice.
�
With increased human travel ito
pens upavenues f or the species to tag along, such asthe Zebra mussel which hosts on ship hulls or
ballast tanks.
8/6/2019 Biology 3709 - Alien Invasive Species
http://slidepdf.com/reader/full/biology-3709-alien-invasive-species 7/14
� Second only to habitat loss, invasive alien speciesare the most significant threat to native species and
bio
diversity.� Newf oundland and Labrador Wild Life Act (1992),
Restricts the import, and possession of non-nativewild life into the province, or onto the island portiono
f the pro
vince fro
m Labrado
r. Pro
hibits the releaseof any wild life that has been imported or that hasbeen propagated from imported stock onto thenatural landscape.
8/6/2019 Biology 3709 - Alien Invasive Species
http://slidepdf.com/reader/full/biology-3709-alien-invasive-species 8/14
� Over 35% of plant species in NL are alien
invasive.
� Newf oundland and Labrador 's flora of approximately 1,500 vascular plant species
comprises perhaps 1,000 native species and500 naturalized species.The latter were
brought here intentionally or accidentally andhave flourished.
8/6/2019 Biology 3709 - Alien Invasive Species
http://slidepdf.com/reader/full/biology-3709-alien-invasive-species 9/14
� One of the most harmful of invasive speciesinNewf oundland is the moose.
�
Intro
duced in the early 1900s the moo
se hasspread throughout the island, bred withoutcheck and is now inflicting serious damage inour national parks and many parts of rural
Newf oundland. A voracious browser, moosehave stripped tree branches as high as theycan reach and munched native shrubs downto their crowns.
8/6/2019 Biology 3709 - Alien Invasive Species
http://slidepdf.com/reader/full/biology-3709-alien-invasive-species 10/14
� The snow shoe hare is also a non-native
island species.
� It too browses native vegetation, but is f ondof young shoots and seedlings.The result is a
dramatic change in boreal f orest recovery,age structure and understory species.
8/6/2019 Biology 3709 - Alien Invasive Species
http://slidepdf.com/reader/full/biology-3709-alien-invasive-species 11/14
� OysterThief (Codium fragile tomentosoides).� A green alga from Japan, first appeared in
easternC
anada in 1989 in so
uthernNo
vaScotia. It also appeared in the Gulf of St.Lawrence in 1996. Uproots eelgrass whichprovides shelter and reproductive and
feeding habitat f or fish, molluscs andcrustaceans.� May overtake kelp beds. Bad f or shell fish
industry.
8/6/2019 Biology 3709 - Alien Invasive Species
http://slidepdf.com/reader/full/biology-3709-alien-invasive-species 12/14
� Green crab, (Carcinus maenus).
� Native to Baltic and eastern Atlantic.Travels
on ships hulls, ballast tanks, ect. It feeds onbivalves including clams, oysters, mussels,
ect.
8/6/2019 Biology 3709 - Alien Invasive Species
http://slidepdf.com/reader/full/biology-3709-alien-invasive-species 13/14
� Trying to kill invasive species is highly
ineffective.Natural predators are the best at
controlling their numbers.� Mussel aquaculture is a common vector of
invasive species transport (e.g. tunicates andthe green crab).
� Eventually an invasive species will becomeless of a threat to its new area, due to its
incorporation into natural f ood webs and
native species adjusting to its presence.
8/6/2019 Biology 3709 - Alien Invasive Species
http://slidepdf.com/reader/full/biology-3709-alien-invasive-species 14/14
� http://www.invasivespecies.gc.ca/english/Lin
kSearch.asp?x=1&f ormAction=SubjectArea
� Coulatti, R. & MacIsaac,H. (2004). A neutralterminology to define invasive species.
Diversity and Distributions. 135-141.
Top Related