Con Bio Set 2 Flashcards
1978
- 1st international congress on con bio
- society for con bio formed
1992
- 5000 members in SCB
- 15 grad programs in US
1996
- first textbooks started to appear
Foundations of Con Bio
1) intrinsic values of biodiversity and entire communities
2) physical environment and living organisms provide vital services and goods
3) physical environment and its organisms add value, knowledge, and meaning to the human experience
5 main problems in con bio
1) conservation of genetic diversity
2) conservation of species
3) conservation of habitat
4) management of landscapes through ecosystem processes
5) sustainable development of human economies and populations
Yellowstone
- earliest history goes back 11000 years - Native Americans
- established as a national park in 1872
1916
National Park Service
conservation
proper use of nature
preservation
protection of nature from use
1892
- Sierra club was established by John Muir
- preservation ethic
- John Muir was a racist
30 by 30
- biodiversity convention set goal of 30 by 30
- governments designate 30% of earth’s water and land area aside as protected areas
Endangered Species Act (1973)
- prohibits unauthorized “taking”
- protection of “critical habitat”
- creation of “recovery plans”
- more than 1100 listed as threatened/endangered
Fire suppression effects
- leads to fuel buildup
- dense regeneration can create a ladder for ground fire
reducing fires –> bigger fires later
How many species are there?
roughly 8.7 million
–> 2.2 million have been named
–> 20000 added each year
endemic
specific to one area, cannot be found anywhere else in the world
Why is rising human population an issue?
- 2.5x food use
- 2x water use
- 3x N&P use
5 drivers of changes in biodiversity
1) habitat change
2) climate change
3) invasive species
4) overexploitation
5) pollution (mostly N&P)
Reasons for habitat loss
- deforestation
- clearing for agriculture
- aquatic habitat loss
- climate change
Why is fragmentation a problem
- forest fragments isolated due to cutting become exposed to greater amounts of wind and solar
- forest edges become hotter and drier
- fragmentation decreases diversity of many organisms
Prairie habitat loss
- converted to till agriculture and pasture
- less than 1% of natural prairie remains
- bison gone
Prairie fires
- fire is necessary to maintain prairies
- species have adapted to fires by having underground root systems and quick recovery
Examples of overexploitation (passenger pigeon)
- used to be one of most abundant birds on earth
- pigeon meat was used as food in 1800s
- commercial hunting in 1860s led to >100000 bird being shipped each week
- last passenger pigeon died in 1914 :(
Examples of overexploitation (American bison)
- used to be 30 mil
- went down to 10000
now at 400000, but only 30000 of them are in the wild - rest are bred for meat in captivity
Examples of invasive species (rabbits in Australia)
- rabbits introduced in Australia and the population exploded
- grazing was devastating to natural animals and agriculture
- two intros of non-native species were used to eradicate rabbits
- .5% were genetically resistant to virus released, so population grew again
Examples of invasive species (lionfish in Florida)
- accidentally introduced to Florida
- has few native predators
- is a strong venomous predator
Ecological effects of zebra mussels
- increased water clarity by 600% by reducing some forms of phytoplankton
- phytoplankton is the basis of the lake food web
- zebra mussels have totally eliminated some native species in certain areas
VULTURES
- faced unprecedented population declines due to poison
- poisoning of carcasses they feed on
- populations of 11 species have plummeted by 87-90%
What contributes to N&P pollution?
- overusing fertilizers
- rainfall picking up animal waste
- rainfall flowing over urban areas where there is no storm water management
- overflow from septic tanks
