Biology 5C ~ Lecture 7 ~ (Conservation Biology)

Conservation Biology:

Seeks to preserve life, integrates several fields: Ecology, Physiology, Molecular biology, Genetics, Evolutionary biology, economics, sociology, law, etc [mission driven discipline]

Global biodiversity crisis:

- conservation biologists are concerned about species loss because of alarming statistics regarding extinction and biodiversity
-more than 1,000 species have become extinct in the last 400 years; this rate is 100 to 1000 times the "background" extinction rate

Global biodiversity crisis cont. (pt.2):

- globally, 12% of birds and 21% of mammals are threatened with extinction
- extinction may be local or global

Extinctions and critically endangered species in numbers

North America: 261 are extinct --- 303 are critically endangered
Mesoamerica: 30 are extinct --- 383 are critically endangered
Caribbean: 50 are extinct --- 242 are critically endangered
South America: 33 are extinct --- 659 are critically endangered
Europe: 30 are extinct --- 398 are critically endangered
North Africa: 16 are extinct --- 52 are critically endangered
Sub-Saharan Africa: 97 are extinct --- 663 are critically endangered
West & Central Asia: 21 are extinct --- 122 are critically endangered
South & Southeast Asia: 36 are extinct --- 745 are critically endangered
North Asia: 7 are extinct --- 32 are critically endangered
East Asia: 20 are extinct --- 189 are critically endangered
Oceania: 180 are extinct --- 324 are critically endangered

Most species loss can be traced to four major threats:

-habitat loss
-introduced species
-overharvesting
-global change

habitat loss:

a forest or ecosystem that gets destroyed for some reason and replaced with some human use that the biodiversity can no longer utilize [ex. cutting down forest for urbanization, putting dams on rivers]

introduced species:

species that are introduced by humans start to grow and take over the ecosystem which has a negative effect on the ecosystems and the species that live there

over-harvesting:

-overuse of natural populations
-plants and animals that are out in natural ecosystems but are still harvested for human use [ex. seafoods--fishing]
-harvesting resources in a way that's not sustainable [hunting too much animal that it causes extinction]

Management strategies: species/population level

-threat management -- identifying the threat
-captive breeding -- zoo [breed & release them]
-reserves

*focusing efforts on a specific species or a specific population of that species [ex. endangered animals]

Management strategies: ecosystem/landscape level

-reserves -- find hotspot areas and build a reserve
-restoration -- repairing damaged ecosystems

*trying to preserve an ecosystem or a landscape that may have many species in it or it may have some critical ecosystem function

Biodiversity hotspot:

-areas that are species of lands that have a very high amount of biodiversity in the area

Protected areas and reserve design:

*zoned reserve - includes undisturbed areas and modified areas that serve as buffer zones
*corridors - connect protected areas and facilitate dispersal

Ecosystem restoration

-the goal is to return degraded ecosystems to a more natural state
-may focus on (re)introducing species or restoring key ecological processes (ex: flow, fire, bioremediation)

Sustainable development

-Sustainable development is development that meets the needs of people today without limiting the ability of future generations to meet their needs
-sustainable development requires connections between life sciences, social sciences, economics, and humanities

Ecosystem services:

processes through which natural ecosystems and their species help sustain human life

Examples of ecosystem services:

-Purification of air and water
-Detoxification and decomposition of wastes
-Cycling of nutrients
-Moderation of weather extremes

major concepts to know:

-what is conservation biology, and how does it integrate different fields? Why do we say it is a "mission-oriented discipline?"
-why do conservation biologists say we are seeing a global biodiversity crisis, and what are the main causes?
-what are the main conservation management strategies, and what is the difference between species/population strategies and ecosystem/landscape ones?
-what is sustainable development?
-what are ecosystem services? what are some examples of them?