Week 10: Conservation Ecology Flashcards
Conservation
The collective name we give to the various actions we can take to slow down or
globally even reverse these losses of species and of biodiversity.
Biodiversity
Biodiversity or biological diversity is the variety and variability of life on Earth. Biodiversity is a measure of variation at the genetic, species, and ecosystem levels.
Restoration
Conservation in a broader
sense, since the aim is to reverse a past failure to con- serve.
Demographic uncertainty
Random variations in the number of individuals that are born male or female, or in the number that happen to die or reproduce in a given year, or in the genetic quality of the individuals in terms of survival/reproductive capacities can matter very much to the fate of small populations. Suppose a breeding pair produces a clutch consisting entirely of females. Such an event would go unnoticed in a large population but could be the last straw for a species down to its last pair.
Environmental uncertainty
Unpredictable changes in environmental factors, whether disasters (such as
floods, storms, or droughts ofa magnitude that occurs very rarely) or relatively minor events (year-to-year variation in average temperature or rainfall), can also seal the fate of a small population. A small population is more likely than a large one to be reduced by adverse conditions to zero or to numbers so low that recovery is impossible. And of course global climate
change may greatly aggravate this influence.
Inbreeding depression
The reduced biological fitness that has the potential to result from inbreeding. The loss of genetic diversity that is seen due to inbreeding, results from small population size. Biological fitness refers to an organism’s ability to survive and perpetuate its genetic material.
Overexploitation
Populations are harvested at a rate that is unsustainable, given their natural rates of mortality and capacities for reproduction.
Introduced species
A species that has been intentionally or inadvertently brought into a region or area. Many introduced species are assimilated into communities without much obvious effect.
Invasive species
An introduced species to an environment that becomes overpopulated and harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage
Extinction vortex
Population may have been reduced to a very small size by one or more of the processes described above, and this may have led to an increased
frequency of matings among relatives and the expres- sion of deleterious recessive alleles in offspring, leading to reduced survivorship and fecundity and causing the population to become smaller.
Protected area
Defined by the International Union for the Conservation of Nature (IUCN, 2008) as ‘a clearly defined geographical space, recognized, dedicated, and managed through legal or other effective means, to achieve the long term conservation of nature with associated ecosystem services and cultural values.”
Marine protected area
All or mostly marine, although
portions of adjacent land areas are often included, par- ticularly when the land is intimately tied to the marine ecosystem in function or culturally.
No-take zone
Areas where no
fishing is allowed. These areas are also well protected from land-based pollution sources and other human
disturbances.
Irreplaceability
Defined as the likelihood of
its being necessary if we are to achieve conservation targets or, conversely, the likelihood that one or more targets will not be achieved if the area is not included.
Ecosystem services
Functions or attributes provided in support of human interests by ecosystems
(natural or managed), generally saving a cost that would otherwise need to be paid.
