Overexploitation, Exotic Species, and Diseases Flashcards
Examples of things facing overexploitation?
- whaling
- ivory
- medicinal plants
- sharks
- bushmeat
- seahorses
How many sharks have been fished out of ocean in last 50 years?
90%
Why are sharks fished?
fins (shark fin soup)
Why are sharks so vulnerable to overfishing?
- delayed reproduction
- few offspring (low fecundity)
What is a reason for chimpanzees decline in population?
hunted for live animal trade and for meat
Why has hunting chimpanzees and other animals become more accessible?
expansion of commercial logging
How profitable is the bushmeat industry?
$1 billion industry
What does the Jane Goodall Institute do?
helps orphaned chimpanzees survive (result of loss of mother due to bushmeat trade)
What are the major targeted groups of the worldwide trade in wildlife?
- primates
- birds
- reptiles
- ornamental fish
- reed corals
- orchids
- cacti
What is the International Whaling Commission?
global body responsible for management of whaling and conservation of whales
What is impacting the recovery of humpback whales?
climate change
What did Kenyan Wildlife Service do to show they are against poaching?
collected illegally traded ivory and made big pile of it and burned it
How many african elephants are killed by poachers each year?
30,000
What are decoy tusks used for?
have gps and are used to track ivory trade
What is the Asian turtle crisis?
- In different Asian countries, turtles are sold at markets and it is depleting populations
- happening worldwide as well
What is the fear with GMOs?
GMO crops will harm birds, insects, soil organisms, other species, and even humans
What is the hope with GMOs?
GMO crops will produce more food and use less pesticides, resulting in an improved water quality and healthier animals
What is an invasive species?
one that arrives (often with human assistance) in a habitat that had not previously occupied, then establishes a population and spreads autonomously
Why are invasive species bad?
likely to cause economic or environmental harm or harm to human health
What are ideal characteristics for an organism to be a candidate to become invasive species?
- good dispersal abilities
- high population growth rates
- ability to reproduce asexually or through self-fertilization
- “genetic fitness”
- broad ecological tolerance
- climatic matching
What makes certain ecosystems vulnerable?
- diverse, undisturbed communities have few invaders (biotic resistance)
- disturbed habitats have more invaders
- human residential areas
- islands
Why are human residential areas vulnerable?
- many European species are commensal with humans (synanthropic)
Why are islands vulnerable?
little history with competitors, predators, parasites, or diseases
Examples of synanthropic species?
raccoons, coyotes, opossums, starlings, cockroaches
What makes a community vulnerable to invasion?
- absence of strong competitors
- absence of natural enemies
- disturbance before or upon immigration
- propagule pressure
- biotic facilitation
What is propagule pressure?
Ex. shipping containers are packed densely with things from around the world and have potential to escape, so have high propagule pressure
What are examples of invasive species animals?
- opossum shrimp
- gypsy moth
- fire ant
- zebra mussel
- cane toad
- brown tree snake
- Burmese python
- lionfish
- Asian carp
- emerald ash borer
- hemlock wooly adelgid
- Dogwood anthracnose
- American chestnut blight
- cogon grass
What does NISIC stand for?
national invasive species information center
What are some GA invasive species?
- Beach vitex
- bradford pear
- Emerald ash borer
- Asian longhorned beetle
- Joro spider
- cuban tree frog
- giant tiger prawn
What happened when opossum (mysis) shrimp were introduced to Flathead lake?
-were introduced to increase kokanee salmon, but salmon couldn’t eat them cuz feed on different levels of lake
- bald eagle and Kokanee salmon depleted in population size, completely disrupted food web
How did gypsy moths become invasive?
were brought over for textile industry and then got loose
What animal has faced decline due to fire ants?
northern bobwhites in Texas, go after eggs
How were brown tree snakes brought over?
Accidently came over to Guam during world war II
How have brown tree snakes impacted guam?
- caused multiple native bird species to go extinct
- introduced to environment that did not have this type of natural predator
- cause power outages (impacts military base)
How did cogongrass spread?
- used as a potential forage crop but hard to kill due to silica content in leaves
- produces a lot of seeds per grass and can spread 15 miles in wind, get caught on animal fur
- can spread due to land management, vehicles, fire plows
- ryzomes, spreads underground asexually
