Spring peeper

## Description

The spring peeper (Pseudacris crucifer ) is a small chorus frog widespread throughout the eastern United States and Canada. They are so called because of their chirping call that marks the beginning of spring. Crucifer is derived from the Latin root meaning "cross-bearing." This could be a reference to the cross-like pattern on the spring peeper's dorsal side.

## Appearance

Spring peepers are tan or brown with a dark cross that roughly forms an X on their dorsa (thus the Latin name crucifer, meaning cross-bearer), though sometimes the marking may be indistinct. They have a body length between less than 25 mm (0.98 in) to 38 mm (1.5 in) and a mass between 3 and 5 g (0.11 and 0.18 oz).

The species has large toe pads for climbing, although it is more at home amid the loose debris of the forest floor.

The color variations of P. crucifer are mostly tan, brown, olive green, and gray. All have a slightly pale yellow coloration on the inside of the thighs. Females are lighter-colored, while males are slightly smaller and usually have dark throats. Females have a bulkier abdomen. Skin color of Spring Peepers is also affected by temperature and light. Coloration is dynamic and adaptable in this species. It can be altered quickly, in 15 to 45 minutes, in order to better camouflage from predators.

Located by its throat, this frog has a vocal sac that expands and deflates like a balloon to create a short and distinct peeping sound. Only males have the ability to make this loud high-pitched noise, and they use it to attract mates.

## Distribution

The southern spring peeper's habitat includes the Gulf Coast from southeastern Texas to southeastern Georgia and northern Florida, United States. Its northern conspecific occurs in the entire United States east of the Mississippi and spreads to eastern and central Canada.

## Behavior

Spring peepers live primarily in forests and regenerating woodlands near ephemeral or semipermanent wetlands. This amphibious species requires marshes, ponds, or swamp regions to support the aquatic environment the eggs and tadpoles need.

In the northern reaches of their range, spring peepers must frequently endure occasional periods of subfreezing temperatures during the breeding season. The species can tolerate the freezing of some of its body fluids, and undergoes hibernation under logs or behind loose bark on trees. It is capable of surviving the freezing of its internal body fluids to temperatures as low as -8 °C (17.6 °F). This species frequently occurs in breeding aggregations of several hundred individuals, and commonly breeds in many small wetlands, including swamps and temporary pools and disturbed habitats, such as farm ponds and borrow pits.

## Diet

Spring peepers are nocturnal insectivores, emerging at night to feed primarily on small invertebrates, such as beetles, ants, flies, and spiders. They do not climb high into trees, but hunt in low vegetation. Spring peepers living in deep, damp forests are active hunters both day and night, whereas those found in woodland edges restrict most hunting and other activity to night.

Tadpoles feed on algae and other organisms in the water. Their predators include great diving beetle larvae (when in tadpole form), snakes, skunks, and larger frogs.

## Reproduction

Spring peepers breed in southern areas from October to March, depending on the local temperature. In northern areas, they breed between March and June, when the warm rains start. P. crucifer typically lays around 900 eggs per clutch, but up to 1000 are possible. Egg clusters are hidden under vegetation or debris at the water base. After they hatch, they remain tadpoles for two to three months before they transform into frogs and are ready to leave the water. Females choose mates based on the speed and volume of these calls. Interestingly, females also discriminate between distinct genetic lineages, with females preferring males of their own lineage, possibly due to the detrimental effects of hybridization. Older, larger males tend to have faster and louder calls that are preferred by the females. A segment of the male population, known as 'satellite males' do not make these calls, but instead position themselves near loud males and attempt to intercept females drawn in by these calls. Males normally call between 15-25 times per minute to attract mates. This can continue from the evening unto 3am. Male spring peepers have also been found to increase the duration and frequency of aggressive calls in response to increased calling intensity from others. These satellite males are also known to circumvent female choice and increase rates of hybridization between spring peeper lineages. The spring peeper can live an estimated three years in the wild.

## Population

### Population number

The spring peeper has no special status in most areas. They are common and widespread frogs in the eastern regions. However, their habitats are quickly changing due to loss of wetlands. In some areas, their populations have decreased significantly.

The species is listed as threatened in both Iowa and Kansas.