Texas Wildlife Science

Abiotic – non-living

Adaptive management – a systematic process for continually improving management policies and practices by learning from the outcomes of previous practices

Aestivate – a dormant state for animals that happens in hot or dry conditions

Allen’s Rule – an ecological principal stating that warm-blooded animals in warmer climates have longer appendages to maximize heat dissipation

Altricial – a bird or mammal that is born without full development that requires extensive parental care

Amplexus – literally “an embrace;” the posture when a male frog grabs a female frog for egg-laying and fertilization

Aquatic – of, or pertaining to, water

Apex predator – a predator at the top of a food chain, without natural predators of its own

Atmosphere – all the gases making up the Earth’s air

Bag limit  – the maximum harvest of fish or game allowed within a given time period

Bask – a “sunbathing” strategy used by reptiles and other animals to increase body temperature to ideal levels for activity

Batholith – a large igneous structure beneath the earth’s surface; may be exposed by erosion

Bergmann’s Rule – an ecological principal that warm-blooded animals in a given species tender to have larger body size farther from the equator

Binomial nomenclature – a standardized system of naming animals with Latin names consisting of a genus name and a species name

Bioaccumulation – the gradual accumulation of substances, such as pesticides or other chemicals, in an organism; can result in high concentrations in animals high in the trophic pyramid

Biodiversity- the variety of living things found in an area

Biogeochemical cycles – the movement and transformation of chemical elements and compounds between living organisms, the atmosphere, and the earth’s crust

Biology – the study of living things

Biomass – the total quantity or weight of organisms in a given area

Biome – a distinct geographical region with specific climate, vegetation, and animal life

Biosphere – all the living organisms on Earth

Biotic – referring to something which is living

Bog – a wetland of soft, spongy ground consisting mainly of partially decayed plant matter called peat

Bolson – a large basin area, usually in arid regions, where water collects and evaporates

Bottomland hardwoods – forested riparian wetlands of East Texas where the streams or rivers occasionally flood beyond their channels into hardwood forested floodplains

Browse line – the boundary between normal plant growth at higher levels and lower portions of plants where they have been stripped back by wildlife or livestock

Browser – an animal that feeds on leaves, soft shoots, or fruits of woody plants

Brumate – a dormant state that reptiles and amphibians exhibit during cold weather

Brushlands – woodlands made up of woody species usually less than 25 feet tall

Buck – a male deer

Bunchgrass – a perennial grass that grows as an individual plant forming a clump of stems

Caldera – a volcanic crater, often resulting from the collapse of the volcano cone

Caliche – a shallow layer of soil or sediment that has been cemented together by the precipitation of calcium carbonate or other mineral material.

Carapace – the upper shell of a turtle consisting of numerous fused plates; the carapace is also fused to the turtle’s backbone

Carnassial teeth – molar teeth in carnivores that are modified for shredding

Carnivore – an animal which eats only other animals; also, a member of the mammalian order Carnivora

Carrion – a decaying animal carcass

Carrying capacity – the maximum number of individuals of a given species that a habitat can sustain indefinitely

Census – a complete count of animals in a wildlife population

Chrysalis – the pupa form of a butterfly in which metamorphosis from larva to adult takes place

Ciénega – shallow wetlands formed by spring seeps in desert regions

Clearcut – a timber harvest strategy in which all or nearly all trees are removed from a forest patch at the same time

Climate – the weather conditions prevailing in an area in general or over a long period 

Climate change – a long-term change in average weather patterns

Climax community – a stable vegetation type that tends to develop over time and includes the animals and plants that are best adapted to the abiotic factors in an area

Coastal Plain – a band of flat topography that parallels the Texas Gulf Coast

Commensalism – a symbiotic relationship between two species in which one species benefits and the other is neither benefitted nor harmed

Community – an association of interacting populations of different organisms in a natural environment 

Compensatory mortality – a situation in which hunting or predation reduces mortality rates from other factors; it applies when limiting factors are density-dependent

Competition – when two or more organisms have a demand for the same limited resources, such as nutrients, space or light.  Competition between two members of the same species is intraspecific competition.  Competition between two different species is interspecific competition.

Compound – a basic building block of matter composed of two or more elements bonded in a specific chemical formula

Conservation – wise use of natural resources

Consumer – an organism that must consume other organisms for their energy needs

Crepuscular – active in the early morning and/or late evening

Cryptic – hard to see as a result of coloration and/or behavior

Deciduous – a broad-leaved tree or shrub that sheds its leaves each winter

Decomposer – an organism that breaks down other dead organisms or parts of organisms in order to obtain energy

Decreaser grass – a species of grass that decreases under heavy grazing pressure; usually these species are desired for both livestock and wildlife

Density-dependent factors – a limiting factor that is increased as density of populations increase

Density-independent factors – a limiting factor that is not affected by population density

Diapause – a period of suspended development in an insect, other invertebrate, or mammal embryo, especially during unfavorable environmental conditions

Dioecious – a plant with imperfect flowers in which the male and female flowers are born on separate plants

Diurnal – active during the day

Doe – a female deer

Ecological niche – the function, position or role of a species within an ecosystem

Ecological pyramid – a graphical representation of the energy in an ecosystem that illustrates the abundance of organisms at each feeding level (also called trophic pyramid)

Ecological succession – include primary succession and secondary succession

Ecology – study of the relationships living organisms have with each other and with their environment, including both biotic and abiotic components

Economics – the study of how wealth is produced and distributed

Ecoregion – a major ecosystem defined by distinctive geography, climate, and biotic communities

Ecosystem – a biological community of a given area and the physical environment with which it interacts

Ecosystem engineers – species that create, modify, maintain, or destroy habitats through their physical activities

Ecosystem services – outputs from nature, such as clean air and clean water, that benefit human welfare

Ecotone – a transition zone between two different ecosystems or ecoregions where characteristics of both can be found

Ectotherm – an animal that uses its surroundings to adjust its internal body temperature

Edge species – an animal that tends to utilize ecotones, or the boundary between two different habitat types or conditions

Element – one of the basic building blocks of matter composed of atoms with the same chemical structure

Emergent vegetation – herbaceous wetland plants that protrude from the water

Emigration – when an animal moves out of a population area

Endemic – a species whose distribution is restricted to a certain area

Endothermic – an animal whose internal body temperature is controlled by its internal metabolism

Ethology – the study of animal behavior

Eutrophication – an overgrowth of algae and aquatic plants due to high levels of nutrients in the aquatic environment

Evergreen – a tree or shrub with leaves that remain green throughout the year

Exotic – a species that is not native to a given area

Exploitation – a symbiotic relationship that benefits one organism but harms another; may also refer to human use of a wildlife resource

Extinction – the dying out of a species or subspecies completely

Extirpation – the dying out of a species or subspecies in a particular area

Fauna – the animal life of a particular natural area

Fawn – a young deer under one year of age

Fecundity – a measure of the reproductive capacity of a population; ratio of young produced to adult females

Feral – an animal originating from domestication or captivity that has established in the wild

Flora – the plant life of a particular natural area

Focal species – a species of plant or animal that is monitored during wildlife management as a measure of the success of conservation strategies

Food chain – part of a food web, the series of linkages that shows how energy is transferred in sequence from a producer to several different consumers, including decomposers

Forb – herbaceous (non-woody), broad-leafed plants

Forest – a habitat with trees grouped in a way so their leaves, or foliage, shade the ground

Fragmentation – a situation in which natural habitats are disconnected or broken into small tracts

Frugivore – a fruit-eating animal

Furbearers- species which may be legally harvested for the sale of their hide or pelt

Game – animals for which hunting regulations, including bag limits, seasons, and methods of harvest, have been adopted

Generalist species – a species of wildlife that can eat many types of food and survive in many types of habitats

Genetic bottleneck – a loss of genetic diversity in a population or species because of a very low population size at some point in time

Genetic diversity – the variety of inheritable traits that occur within a species

Geologic fault – cracks in the earth’s crust resulting from stress and differential movements between sections of crust, often resulting in visible changes in landforms on the earth’s surface

Geosphere – the rocks and minerals making up the Earth’s land

Gestation period – the amount of time that a mammal develops within the uterus while being nourished by the placenta

Gilgai – depressional areas that occur in blackland soils that can support moisture-loving species

Grasslands – areas dominated by grasses, with tree or shrub canopies covering less than 25 percent of the area

Greenhouse effect – the trapping of the warmth of the sun near the earth’s surface due to the presence of atmospheric gases that prevent heat from escaping

Group selection – a forestry technique that harvests small groups of trees, creating light gaps in the forest, but maintaining forest diversity

Habitat – the natural environment for an organism that supplies all their life needs.  Habitat must provide food, water, shelter, and adequate space. 

Habitat corridor – a linear tract of habitat that is conserved or restored in order to allow wildlife movement between two other fragments of habitat

Halophyte – a plant that grows in environments with high salinity

Hardwood tree – flowering trees, such as oaks and elms, that are usually deciduous and slow-growing; they produce a dense, hard wood

Herbivore – an animal that eats only plants

Home range – a familiar tract of habitat that an individual animal passes through on a regular basis to obtain food, seek shelter, or find mates

Homeothermic – an animal that maintains a constant internal body temperature despite the external temperature variations

Humus – the organic layer of soil formed when soil microorganisms break down dead plants and animals

Hydric soil – soil that is permanently or seasonally saturated by water, resulting in anaerobic conditions, as found in wetlands

Hydrology – the distribution and movement of water in a system

Hydrophytic – water-loving

Hydrosphere – the water in the Earth’s oceans, rivers and lakes

Igneous rock – a rock that is formed from cooled magma or lava; often with air bubbles or large crystals within the rock

Immigration – when animals move into a new area

Increaser grass – a species of grass that increases under disturbed conditions or heavy grazing pressure; usually they provide poorer grazing nutrition and wildlife structure

Indicator species – species whose presence or abundance in an ecosystem reflect a specific environmental condition

Induction—gathering observations and data from many sources and circumstances and then developing theories

Insolation – the amount of solar radiation reaching a given area

Intrusive igneous rock – rock formed by cooling of magma underground, producing various shapes, such as stocks, laccoliths, sills, and dikes, where magma pushed its way into overlying geologic formations

Invasive species – alien species whose introduction does or is likely to cause economic or environmental harm or harm to human health

Keystone species – species that significantly influence ecosystem structure, composition, and function through their activities

Lacustrine wetlands – wetlands that form along lakes or ponds

Lava dome – a mound of lava that is emerging from the vent of a volcano

Limiting factor – a feature of habitat, biology, or ecological communities that constrains a population’s size and slows or stops it from growing.

Marsh – a wetland dominated by reeds and other grass-like plants

Mast – food sources produced by woody plants, such as acorns, nuts, and fruit

Mesopredator – a medium-sized animal that hunts other animals, but may not be at the top of the food chain; examples include foxes and raccoons

Metamorphic rock – rock that is formed by the transformation of other rock types under pressure and heat; often demonstrate flattened crystals or bent layers

Migration – a regular seasonal movement of animals back and forth between a breeding ground to a wintering ground, usually at different latitudes; some species also move between different elevations

Mima mounds – small mounds up to one meter tall that occur in tallgrass prairie and may support unique species

Mitigation – creation or restoration of a habitat to make up for a habitat loss as the result of a project at another site

Model – a representation or simulation of a real-life phenomenon, organism, or process. Concept-process models can be used to predict. how changes in one part of a system may affect other parts of the system

Monoculture – a planting of crops or timber that is composed of only one type of crop or tree

Monoecious – a plant with imperfect flowers (separate male and female flowers) in which an individual plant has only male or female flowers

Mortality – the ratio of the number of deaths to the size of the population; death rate

Motte – a small grove or clump of trees in open prairie country

Mutualism – an association between two different species in which both species benefit

Myrmecophagous – an organism that specializes in feeding on ants

Natality – the ratio of the number of births to the size of the population; birth rate

Natural History – the scientific study of plants and animals, based primarily on observation of the natural world

Natural Selection – the process in nature whereby organisms that have more suitable characteristics tend to survive and reproduce

Naturalist – a person who observes and studies wild flora and fauna

Nature-based tourism – travel focusing on wildlife or other natural features; sometimes called ecotourism

Neotenic – retaining larval characteristics even as an adult

Nocturnal – active at night

Nongame – any of a variety of animals that do not have seasons and bag limits designed for harvest; most wildlife is nongame

Omnivore – an animal that eats both plants and animals

Organic – a substance containing carbon associated with a living organism

Ornithology – the study of birds

Oviparous – an organism that lays eggs; young develop within the egg through incubation

Ovoviviparous – an organism that produces eggs that are hatched in the body; young are born live; characteristic of some reptiles

Oxbow – a lake or wetland that is formed from the ancient meanders of a river

Perennial – a plant that lives for three years or more

Pheromone – a chemical substance produced by an animal that can affect the behavior of other members of its species

Photosynthesis – the process by which plants and other producers use chlorophyll, sunlight, water, and carbon dioxide to produce and store sugars

Physiography – the study of the physical abiotic features of the earth’s surface

Plastron – the lower shell of a turtle consisting of several bony plates fused together

Plate tectonics – theory that the earth is made up of rigid plates at the surface that move on a fluid mantle beneath

Playa lake – round depressions in the Southern High Plains of the United States that fill with water when it rains forming shallow temporary lakes or wetlands

Poikilotherm – an animal whose internal body temperate can vary considerably

Population – a group of organisms belonging to the same species occupying a particular area at the same time

Prairie – a term, most often used in North America, to describe a wide expanse of grassland habitats

Prairie potholes – depressional wetlands scattered in a grassland habitat; may be formed by wind or glaciers

Precocial – a mammal or bird that is born well-developed with an ability to move about quickly

Predator – an animal that captures and eats other animals (their prey)

Prescribed fire – a controlled fire set intentionally for purposes of land management

Prey – an animal that is hunted by another animal (their predator)

Primary succession – type of ecological succession following a severe disturbance in which plants and animals colonize a barren habitat, often with no soil yet present

Proboscis – a flexible tubular elongated sucking mouthpart in insects

Producer – an organism that can produce its own food, usually by capturing energy from the sun to complete the process

Quadrat – a frame of some size in which organisms are counted in order to make estimates about the population in general

Rangeland – land on which the indigenous vegetation (climax or natural potential) is predominantly grasses, grasslike plants, forbs or shrubs and is managed as a natural ecosystem

Resaca – refers to an oxbow lake found in South Texas, often formed from the Rio Grande

Riparian – refers to an area along the bank of a river or stream

Savanna – patches of woodland scattered within a grassland, usually with 10%-50% woody canopy cover

Scat – fecal droppings from a wild animal

Science – a system for discovering general truths or laws about the natural world as obtained and tested through the scientific method

Scientific method – a method of learning about the natural world that involves observation, measurement, experimentation, and the formulation, testing, and modification of hypotheses

Secondary succession – a type of ecological succession that occurs after a disturbance disrupts a community but leaves some life forms present

Sedimentary rock – a rock formed when sediments deposited by wind or water consolidate; often show layers and/or sediment grains

Seed-tree cut – leaving a small number of mature trees during a timber harvest so that they can provide seeds for regeneration of the forest

Selective cutting – a forestry management technique that uses harvest of individual trees to maintain a diversity of tree ages and species in the forest

Sentinel species – a species whose population changes can indicate a change in ecosystem structure or function

Sere (or seral stage) – a series of different plant communities that change with time

Shelterwood cut – leaving a moderate number of mature trees during a timber harvest so that they can provide seeds for regeneration of the forest and some habitat for wildlife

Shrubland – habitat composed of woody plants generally less than nine feet tall scattered throughout arid or semi-arid regions (less than 30 percent woody canopy coverage)

Snag – dead trees that are left upright to decompose naturally

Sociology – the study of human society

Soil horizon – a layer within the soil with recognizable differences in chemistry, biology, and physical structure from the layers above and below it; often represents different ages of the soil

Soil profile – the vertical arrangement of the soil horizons from the soil surface down to the solid rock below

Songbird – a member of the avian order Passeriformes; usually small in size, also called perching birds or passerines

Specialist species – a wildlife species that has very specific habitat or food requirements; it may disappear if those resources are not available

Species – a group of living organisms consisting of similar individuals capable of interbreeding

Spring-seep – a term for wetland habitats formed when groundwater discharges to the surface

Subspecies – populations that have the potential to produce young, but live in different areas and vary in size, shape, or other physical characteristics

Sustainable harvest – a policy of harvesting or collecting animals or plants at a level that allows the population to regenerate and maintain itself

Swamp – forested wetland, usually with water present year-round

Symbiosis – a close relationship between two different species in one depends upon the other

Taxonomy – the science of naming and classifying organisms

Terrestrial – found living on land

Territory – a habitat area defended by an organism or a group of organisms from other members of the species or similar species

Thermoregulation – strategies that serve to adjust and maintain an internal body temperature; some species thermoregulate internally, whereas others use external means

Topography – the arrangement of the natural physical features of an area

Transect – a straight line that cuts through a natural landscape so that standardized observations and measurements can be made

Trophic level – refers to “feeding,” it is a level in a food chain, food web, or ecological pyramid that depicts a stage in energy flow in the ecosystem

Umbrella species – species that have either large habitat needs or other requirements whose conservation results in many other species being conserved at the ecosystem or landscape level

Ungulate – a hooved animal

Viviparous – an organism that gives birth to live young that are nourished in the body by the mother

Water guzzler – self-filling, constructed watering facilities that collect, store, and make water available for wildlife

Waterfowl – ducks and geese; members of the order Anseriformes

Wet meadow – a type of shallow marsh that commonly occurs in poorly drained grassland areas

Wildlife – terrestrial or semi-terrestrial non-domesticated vertebrates existing in a natural or semi-natural wild environment

Wildlife Management – implementing changes to populations, habitat, and human use to produce some desired result

Wildlife science – the study of animals and their environments, with a focus on how to apply ecological knowledge to balance the needs of wildlife with the interests of humans

Zygodactylus – bird feet in which two toes point forward and two toes point backwards; found in woodpeckers and roadrunners