Threats 1/2 Test

alien species

an organism living outside its natural geographic range due to direct or indirect human activity

allee effect

a population of species that’s so small that it’s difficult to find mates and reproduce (depend on colony)

background extinction

continuous, low-level, natural rate of species loss that occurs over geological time outside of major catastrophic events

biological imperialism

modern conservation efforts prioritize specific agendas over ecological relationships

biological magnification

bioaccumulation

process by which toxin concentrations increase in living tissue concentrations/increase through food chain

bush-meat

harvest of wild animals for food (little is wasted)

bycatch

catching something with no intention of catching it

commercial exploitation

using resource for commercial gain

ex: overfishing

core area

part of a patch not impacted by edge effects (fragmenting habitats decreases the core area more and more)

darlington model of species-area relationship

for ocean archipelagos, the number of species roughly doubles for every tenfold increase in island area

degraded carrying capacity

permanent or long-term reduction in an environment’s maximum sustainable population size caused by resource depletion, habitat destruction, or ecological damage

ecological extinction

there is a population, but not enough of a species to complete their ecological function

edge effects

changes in a population or community structures that occur at the boundary of two or more adjacent habitats

endemic species

species only lives in small area

environmental acidification

ongoing decrease in pH of earth’s oceans, soils, and freshwater systems caused by absorption of anthropogenic carbon dioxide (CO₂) and acidic air pollutants

exotic species

non-native organisms introduced intentionally or unintentionally by humans into new ecosystems

extinct in the wild

a species is not in its natural habitat, or its natural carrying capacity for an ecosystem

extinction debt

animals are going extinct before we can find out about them going extinct

extinction vortex

things that causes populations to get smaller and smaller

extirpation

a species is gone from a region they’re supposed to be in

fragmentation

modifying habitats so much that the habitat is broken apart, leading to less genetic exchange

global extinction

every place on earth that a species lived in is gone

habitat attrition

not enough habitat for a species

habitat degradation

human or environmental disruptions reduce the quality of an ecosystem so it cannot properly support its native plants and animals, even though the physical area is not completely wiped out

habitat destruction

when a natural environment is altered on cleared so severely that it can no longer support its native species, leading to displacement, starvation, or death

habitat dissection

cutting effect of linear barriers that divides continuous surface into separate parts

habitat perforation

creation of holes or small clearings within large, pre-existing, and otherwise continuous natural landscape

indirect exploitation

benefiting from resource without directly being involved with it

intentional introductions

deliberate release, transport, or planting of non-native species into a new environment

introduced species

an organism brought intentionally or accidentally into a new region outside of its ecosystem

island biogeography model

explains how species richness and diversity are maintained on isolated islands based on dynamic balance between immigration and extinction

IUCN

largest global environmental organization; can determine if species is extinct or critically endangered with species risk listings criteria (red list)

light pollution

presence of excessive, misdirected, or inappropriate artificial light in outdoor and indoor environments

neodemic species

species that just speciated recently

non-point source pollution

sources that can’t be pinpointed from one location (greenhouse gases, acid rain, water quality)

paloendemic species

all its relative species have gone extinct

plasticity

ability of a species to adapt

point source pollution

sources that can be traced back to (oil spill, sewage release, light pollution)

regional extinction

a species is doing fine in one region, but not another

resource specificity

a species specifically requires a resource to survive

species-area relationship

number of species increases with size of habitat

S = C*A^z

S = # of species

C = constant

A = area

z = migration potential

subsistence exploitation

utilizing wild plants and animals to live

unintentional introductions

accidentally transporting or releasing a species outside of their natural ecosystem

vulnerability

the degree to which a species is threatened to extinction from external threats