Aquifer - An underground layer of gravel, porous rock or other earth material where water accumulates and is of adequate quantity and quality to yield economically important amounts for human use.

BCP - Acronym for Balcones Canyonlands Preserve. This refers to the land.

BCCP - Acronym for Balcones Canyonlands Conservation Plan, the Habitat Conservation Plan that was approved by U.S. Fish & Wildlife Department in 1996. This refers to the plan.

BCNWR - Acronym for the Balcones Canyonlands National Wildlife Refuge. This acreage is separate from the BCP and is under direct management of the U.S. Fish & Wildlife Department.

Dual Management lands - lands whose management is shared between the Balcones Canyonlands Preserve program within the Austin Water Utility and the Parks & Recreation Department.

Conservation easement - As used for the WQPL program, the City buys certain values and uses from the owner of the land. These may include development rights, rights for commercial activities, or specific resource management actions.

Endangered species - is defined by the Endangered Species Act as "a species in danger of extinction throughout all or a significant part of its range."

Endemic - Descriptor for species that are found in a specific geographic area, be it an island or an area of particular environmental conditions.

Fee simple - This term explains full ownership of property. There are no mortgages or other similar encumbrances on the title to the property.

Feral - This is an adjective to describe an animal that has returned to a wild state from being domesticated. On the Wildlands, this term is used when discussing feral hogs whose behavior is similar to wild animals even though their ancestors were once domestic livestock.

Generalists - Plants and animals that exist over a wide area.

Ground water - Water that moves and is stored under the earth's surface.

Karst - a term that describes a terrain formed from the dissolution of limestone, dolomite or gypsum and characterized by caves, sinkholes and underground streams.

Neo-tropical migratory songbirds - These Western Hemisphere species of birds spend more than half of the year wintering in Mexico, the Caribbean Islands, and Central and South America, and migrate to the temperate areas of the United States and Canada in the spring and early summer to breed.

Recharge - Movement of water deep underground into aquifers.

Species of Concern - animals that may become endangered if not protected.

Watershed - A geographic basin which all drains to a stream, lake, aquifer or watercourse.

Wildland - Land valuable for providing habitat for native plants and animals and where the ecosystem is not distributed for purposes of agriculture, urban or industrial use.

Wildland urban interface - the area or zone of interaction between urban or suburban human populations and the native plants, animals and natural features of wild and undisturbed land.