Vernal Pools

Vernal Poolslineline

Glossary of Vernal Pool Terms

Amplexus - The mating embrace of frogs and toads during which time the male grasps the female from behind with his forelegs. The male externally fertilizes the eggs as they are released by the female.

Basal Area - The cross sectional area of trees measured at 4.5 feet above the ground. The basal area for a group of trees is calculated by measuring the area of each tree in the sample then adding them all together. Logging activities are often described in terms of amount of basal area cut.

Clean Water Act - The Clean Water Act is a 1977 amendment to the Federal Water Pollution Control Act of 1972, which sets the basic structure for regulating discharges of pollutants to waters of the United States.

Cyclic Drying - A distinguishing feature of seasonal pools is the hydrologic cycle of drought and flood. Seasonal pools fill with water during wet times of the year and slowly dry up during dry times of the year. Depending on the characteristics of a pool and the amount of rainfall in a particular year, pools may dry up and refill multiple times a year, once a year, or on a semi-annual basis.

Endangered Species Act - The purpose of the ESA is to protect and recover imperiled species and the ecosystems upon which they depend. It is administered by the Interior Department’s U.S. Fish and Wildlife Service (FWS) and the Commerce Department’s National Marine Fisheries Service (NMFS). The law prohibits any action, administrative or real, that results in the "taking" of a listed species, or adversely affects habitat. Importing and exporting listed species across state lines and to foreign countries is also prohibited.

Ecosystem - A natural community of organisms and the physical environment functioning as an integrated unit. Forests, wetlands, and oceans are all types of ecosystems.

Exuviae - Invertebrates must shed their outer skin in order to grow. The exuviae is the cast-off skin. It retains a remarkable amount of detail of the larva that shed it. The skin is the exoskeleton of an invertebrate.

Exoskeleton - The hard outer covering over the body of an animal such as the shell of an insect, mollusk, or crustacean. Insects must periodically molt their exoskeleton in order to grow. The shed skin of an insect is called the exuvia.

Habitat - The place that provides all the things a plant or animal needs to live and grow. Some animals require one type of habitat while young and a different one as an adult.

Herpetofauna - The name for reptiles and amphibian species when they are put together in one group. This group includes frogs, toads, turtles, salamanders, snakes, and lizards.

Hydrology - A science dealing with the properties, distribution, and circulation of water on and below the earth's surface and in the atmosphere.

Larva (pl. larvae) - The immature stage of many invertebrates, amphibians, and fishes. The larva looks very different from the adult form. Larvae must undergo metamorphosis before assuming adult characteristics.

Metamorphosis - The transformation of an animal during its life cycle from larva to adult. Metamorphosis is a rapid and significant physical transformation; examples are the tadpole changing into the frog or the caterpillar changing into a pupa then into an adult butterfly.

Metamorphs - Young immature adults that have recently transformed from the larval stage.

Vernal Pool - Small, shallow wetlands that go through a drying phase most years (usually in the summer), have no fish, and are not permanently connected to another body of water, though they may be temporarily connected during flooding events. They may also be called seasonal pools, temporary pools, autumnal wetlands, or ephemeral wetlands.

Vernal Pool Facultative Species - Species that use seasonal pools for some part of their lifecycle. Facultative species have physical or behavioral adaptations that allow them to successfully utilize seasonal pools but they can also survive in permanent wetland habitats.

Vernal Pool Indicator Species - Animal species that require seasonal pool habitats to complete some phase of their life cycle. They may also be called vernal pool obligate species.

Slash - The tops of trees, roots of trees, and other debris that are left behind after logging. Slash is often intentionally left on the ground to encourage new tree growth by minimizing deer browse of young shoots. Deer avoid the tangled slash piles, preferring to find food that is easy to reach.

Spermatophore - A gelatinous packet of sperm produced by male salamanders that is deposited on the ground or in the water. A female picks up the spermatophore to fertilize her eggs.

Wetland - An area that is regularly saturated by surface water or groundwater and supports vegetation that is adapted to wet soil conditions. Some wetlands like bogs and swamps are wet year-round; others like seasonal pools are wet for only part of the year. Wetlands provide habitat for plant and animal species that depend on moist areas for survival.