Wildlife Mangement exam 2.2 Earth, Land, and Habitat

What proportion of the Earth's surface is covered by land and water?

Land = 30%, Water = 70%. Most water is salt water; freshwater makes up less than 1% of Earth's surface.

What proportion of Arizona is land vs. water?

Land = 99.7% (113,642 sq mi), Water = 0.3% (364 sq mi). Water is especially limiting.

Why is it important to study and understand biological communities?

They represent associations of plant and animal species, help explain species distributions, and guide conservation/management decisions.

What are the three main ways biological communities have been defined?

Life zones (Merriam 1894)

Biomes

EPA Ecological Regions (Levels I, II, III)

What are life zones?

Vegetation communities defined by climate, elevation, and temperature, often in mountainous areas. Introduced by C.H. Merriam in 1894.

How are life zones different from other classifications?

They focus on a finer scale, often within smaller or localized areas.

How does elevation influence plant communities?

As elevation increases: temperature decreases, precipitation increases. creating different climate zones.

This leads to distinct plant communities at different elevations — for example, desert scrub at low elevations, pine forests at mid elevations, and alpine meadows near the peaks.

How does aspect influence plant communities?

-North-facing slopes: cooler, wetter, more vegetation.

-South-facing slopes: warmer, drier, less vegetation.

What is the rain shadow effect?

Precipitation falls on windward mountain slopes; leeward slopes are drier. Common in the western US.

How does latitude influence plant communities?

As latitude increases (further from equator), temperature and direct sunlight decreases for the same elevation. means less vegetation

How do latitude and elevation interact for ponderosa pine?

-At lower latitudes (like Arizona), temperatures are warmer, so ponderosa pines are found at higher elevations (around 5,000–10,000 ft) where it’s cooler.
-At higher latitudes (like Montana), the climate is already cooler, so ponderosa pines grow at lower elevations (around 2,000–6,000 ft).
-In short: As latitude increases, the elevation range where ponderosa pines can grow decreases because higher latitudes already provide cooler conditions.

What is a biome?

A major ecological community of plants and animals, defined by climate, and spanning regions or continents.

Why is Arizona considered ecologically diverse?

It contains deserts, grasslands, chaparral, woodland, forest, and tundra — a wide range of biomes.

How is the desert biome subdivided?

Cold desert (sagebrush)

Warm desert (Sonoran, Mojave, Chihuahuan, Baja)

What are the three EPA levels of ecological regions?

Level I: broad (e.g., "Deserts")

Level II: medium (e.g., Cold vs. Warm deserts)

Level III: fine-scale (e.g., Mojave Basin, Sonoran Desert, Baja CA Desert, etc.)

What are the three main factors of habitat?

Biotic - living components (vegetation, predators, competitors).

Abiotic - non-living components (temperature, precipitation, topography, water).

Human - impacts from people (hunting, development, management).

What does it mean that habitat is species specific?

Each species has unique adaptations; habitat for one species may not work for another.

Why is correct habitat terminology important?

Misuse can lead to mismanagement of wildlife and conservation errors (Krausman & Morrison 2016).

What are the primary threats to wildlife in the US vs. China?

US: habitat loss, then pollution, invasives, overexploitation, disease.

China: habitat loss and overexploitation, followed by pollution.

What are the three components of habitat fragmentation (Andren 1994)?

-Reduced area (loss of habitat)

-Increased isolation (patches farther apart)

-Increased edge (negative edge effects)

What is landscape connectivity?

The degree to which landscapes allow movement of organisms or processes. More connectivity = more movement. It is both species- and landscape-specific.

What can be done to maintain connectivity?

Identify and conserve key habitats and connections, mitigate barriers like roads with overpasses/underpasses, and reduce urbanization impacts.

What are crossing structures?

Overpasses or underpasses that allow wildlife to cross linear barriers (roads, canals, railroads).

How do wildlife species respond to urbanization in Phoenix Valley?

Species distributions shift along a wildland-to-urban gradient. Wildlife cameras reveal which species persist or decline. Data helps design conservation strategies in urban settings.

What is an ecological disturbance?

A sudden change in environmental conditions that alters ecosystems. Disturbances can be natural (fires, floods) or human-caused, and many species are adapted to them.

Why are disturbances important for ecosystems?

They create new habitat conditions; many species are adapted to exploit disturbed environments.

What is latitude?

The distance from the equator, measured toward the north or south poles. Temperature decreases as latitude increases at a given elevation.

What is a life zone?

An early ecological classification (Merriam 1894) describing vegetation communities based on climate, especially elevation and temperature in mountainous areas.

What is a biome?

A major regional ecological community of plants and animals, usually defined by climate (temperature and precipitation), occurring across regions or continents.

What is an ecoregion?

A hierarchical ecological classification system (EPA Levels I-III) that groups areas by broad to fine ecological patterns, such as deserts, cold/warm desert types, and specific subregions like the Sonoran Desert.

What are biotic communities?

Associations of plant and animal species living together, defined by interactions among organisms and their environment.

What is a bioclimatic envelope?

The range of climate conditions (temperature, precipitation, etc.) within which a species or community can survive and persist.

What is habitat?

The place where a species lives, defined by landscape conditions and shaped by biotic, abiotic, and human factors; species-specific.

What is habitat fragmentation?

The process of breaking a continuous habitat into smaller patches, characterized by reduced area, increased isolation, and increased edge effects.

What is landscape connectivity?

The degree to which the landscape facilitates or impedes movement among habitat patches; connectivity is species- and landscape-specific.

What are crossing structures?

Overpasses or underpasses that allow wildlife to safely move across barriers like roads, railroads, or canals, reducing fragmentation effects.

What is an ecological disturbance?

A sudden environmental change that rapidly alters ecosystems, sometimes temporarily, creating new habitat conditions; many species are adapted to such disturbances.