Case Studies:
Flying Fox: these are actually BATS!
They are POLLINATORS!
Kudzu: The INVASIVE vine that is taking
over North Carolina among other
states! It was brought over from Japan
ON PURPOSE!
African “killer” bees
• Bees brought to South America for Scientific
Research, but they escaped and are now in
the U.S.
Pollinators
• KEYSTONE species
• Without pollinators, many different plants
can’t reproduce.
• Help to start the food chain
• Examples: flying foxes, bees, hummingbirds
Fish
• Good “indicator species” because
– Found everywhere
– Live in water (first indication that something’s
wrong with water – for example: male fish turning
female…)
Zebra Mussels
• Invasive species! Accidentally introduced to
the Great Lakes.
• Causing a lot of harm to lake ecosystems and
millions of $$$ in damage
The spread of zebra mussels…
Kelp
• Tall weeds that grow in the ocean
Kelp provides a lot of habitat for
others..
• Sea otters play a “key” role in maintaining
kelp; they eat the sea urchins that would
otherwise eat up all of the kelp (HINT!! Relate
this to wolves/elk/willows and aspen trees)
• Picture of sea otter eating a sea urchin:
Passenger Pigeons
• Biologically extinct! Meaning: GONE
FOREVER!!
– 1914
Amphibians
• Good indicator species:
– Live both in water and on land
– Permeable skin
– Found everywhere
– Disappearing FAST!
Dung Beetles
• KEYSTONE! Help to recycle nutrients!
• Use other animals’ feces: bury it for FOOD or
to lay eggs
Water Hyacinth
• From the video
• Accidentally introduced
• Lake Victoria, Africa
Nile Perch
• From the video
• Introduced ON PURPOSE!
• Caused massive extinction of species in Lake
Victoria
Weevils
• From the video
• Biological control of water hyacinth
• SUCCESSFUL
however… Gov’t
still used chemicals
Sea Otters
• KEYSTONE
• Maintain kelp (which provides habitat for
many other species)
Brown Tree Snake
• Invasive! Accidentally introduced to GUAM –
caught a ride on a boat??
• Overrunning Guam, taking over the island!
• Venomous
Cane Toads
• Invasive! Introduced to Australia on purpose
to control the cane grub which was eating the
sugar cane crops. The Cane Toad and Cane
Grub never come into contact with each
other… not a very well thought out plan…
More cane toads…
• TAKING OVER AUSTRALIA!!!
• Poisonous to would-be predators
Top Predators
• KEYSTONE!!
• Sharks, wolves, bears, tigers, big cats…
• Think: wolves in Yellowstone!!
Elephants
• Foundation species: they maintain the
savanna – take down/trample trees to keep
grasslands as grasslands. (Bison do the same
thing for North American Grasslands)
Asian Carp
• Invasive!
More Asian Carp
• Introduced on purpose to certain areas but due to flooding,
they escaped.
• The following agencies are working together to install and
maintain a permanent electric barrier between the fish and
Lake Michigan to prevent the carp from entering the Great
Lakes:
• U.S. Army Corps of Engineers
• EPA
• State of Illinois
• International Joint Commission
• Great Lakes Fishery Commission
• U.S. Fish and Wildlife Service
More on the carp…
• They can out-compete native fish for food and
therefore drive native fish populations into
extinction.
Fire Ants
• Invasive! Accidentally introduced to the U.S.
from a docked ship that came from South
America.
Sharks
• Top predators… so they are KEYSTONE!
– We kill ONE MILLION sharks for every shark that
kills or injures one person.
Whooping Crane
• Nearly went extinct with only 16 left in 1941.
• Efforts have helped the population grow to
over 200 but they are still ENDANGERED.
• Biggest threat today: loss of wetlands
• Need FLYWAYS as they migrate up to Canada
to mate/reproduce.
Whooping Cranes…
California Condor
• Scavengers
• Largest flying birds in North America
• Shot… poisoned… slow to reproduce… need a
LARGE range… they almost went extinct
• SUCCESSFUL captive breeding program!!
• Still ENDANGERED today.
Condor…
Mountain Gorilla
• Endangered!! Found in Central Africa – subject
to loss of habitat, poaching, and the many
wars that have taken place/are still taking
place there…
Many are taken and sold…
• Many of the adults are killed trying to protect
the babies which are sold for profit.
Blue whale
• Endangered! Many marine biologists feel that
it’s too late to avoid extinction…
• World’s largest animal.
• Take 25 years to mature and reproduce! Only
one offspring every 2 – 5 years.
Giant Panda
• Specialist
• Endangered
Carolina Parakeet
•
•
•
•
Native to the U.S. – EXTINCT!! Because:
They were considered a “pest”
Habitat taken away
Feathers were used in hats…
Prairie Dogs
• Prairie dogs were considered “pests”
• Large scale poisoning “program” reduced the
numbers drastically!
• They were a food source for the black footed
ferret so the ferret almost went extinct as
well.
Poisoned prairie dogs…
Black Footed Ferret
Pros and Cons of Captivity, Seed Banks,
Botanical Gardens etc…
Next two slides
PROS
• Preserves genetic information (gene banks)
• Preserves species (build up populations??)
• Education and awareness
Cons
• Success rate varies from “successful” to “not
at all”
• $$$$$$$$$$$$$$$$$
• Not enough individuals to maintain a
population
• Captive animals often kept in insufficient
facilities (Ex: killer whales “stored” in what is
essentially a bathtub when they are used to
having a range that spans hundreds of miles).