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by Christopher A. Urban Chief, Natural Diversity Section and defined Frogs and toads are in the class Two of Pennsylvania’s most common and “Amphibia.” have species are the eastern backbones like , but unlike mammals they cannot internally ( americanus americanus) and the pickerel regulate their body temperature and frog ( palustris). These two species exemplify are therefore called “cold-blooded” (ectothermic) . This means the physical, behavioral, that the has to move ecological and habitat to warm or cool places to change its body tempera- similarities and ture to the appropriate differences in the comfort level. Another major difference frogs and toads of between amphibians and Pennsylvania. other animals is that amphibians can breathe through

the on photo-AndrewL. Shiels

www..state.pa.us Pennsylvania Angler & Boater • March-April 2005 15 land and absorb through the weeks in some species to 60 days in (plant-eating) beginning, they have skin while underwater. Unlike reptiles, others. Frogs can become fully now developed into amphibians lack claws and nails on their developed in 60 days, but many (insect-eaters). Then they leave the toes and fingers, and they have moist, species like the frog and bullfrog water in search of such as small permeable and glandular skin. Their can “overwinter” as in the insects, and other inverte- skin lacks scales or feathers. bottom of and take up to two brates. Frogs and toads belong to the to transform fully into adult Where they go in search of this Anura. Anurans are frogs. As the tadpoles metamorphose food is often what separates the tailless amphibians. They have a short (develop) into frogs or toads, their different frog and toad species. Some backbone with modified and legs back legs first “grow” from their small anurans remain close to their aquatic designed for and hopping. bodies. Soon thereafter their front birthplace and live their entire lives Unlike , anurans possess a closely associated with an aquatic well-developed external habitat, such as a , lake, eardrum, or tympanum, stream or . Other which they use to anurans take on detect predators, more of a prey and terrestrial mates. existence,

Eastern American Toad

photo-Tom Diez

occupying Anuran drier places life cycle such as upland Anurans, like most woodlands, grassy other amphibians, have meadows and rocky two distinct life phases— hillsides. In these environ- aquatic and terrestrial. They hatch ments frogs and toads spend the from jelly-covered into an aquatic remainder of their lives foraging, environment as long-tailed, legless and legs “pop” out of their bodies and brumating (winter ), lungless larvae, or tadpoles (also known their slowly begin to absorb into estivating (summer dormancy) and as “pollywogs”), which breathe with their bodies. breeding. like fish. In this life phase the At the beginning of this second life Frogs and toads are typically develops quickly by feeding mainly on phase, the young frogs or toads (called nocturnal (active at night). Unlike algae, and dead animal matter froglets or toadlets) develop and other reptiles and amphibians, adult found on the bottom of ponds, lakes and begin to breathe air. At this stage, frogs and toads have vocal chords. streams. Toads tend to have a brief their diet changes dramatically. From They vocalize, or “sing,” during the larval stage, lasting from as little as two their humble, mainly herbivorous mating season. Males have a species-

16 Pennsylvania Angler & Boater • March-April 2005 www.fish.state.pa.us specific call that attracts females spit out the toad. Predators to a small area in an aquatic quickly learn to avoid toads. habitat that they defend Unless toads are from other males. Pickerel handled roughly, Mating occurs they will not externally; as Frog secrete the poison each female from the skin. may lay In addition, thousands of toads won’t eggs, males in give you warts, but secrete sperm wash your that forms a hands after protective jelly handling them around the anyway, as you eggs. would after photo-Andrew L. Shiels The cycle handling any wild continues. However, animal or herptile. tadpole predators are Toads are active abundant and include hunters that move about in , diving and search of prey. Their short legs hellgrammites. Juveniles and adult assist them with hunting insects. anurans also attract a diverse group most of our frogs also live at the ground When a toad spots an insect, it crawls of predators including , level, several species dwell in trees and on all four feet within striking distance , , , foxes and shrubs and come down to the ground of the insect and then quickly flicks . Only a small percentage of only to breed. The color and camou- out its long, sticky (attached to the several thousand eggs that were flage pattern on frog and toad skin helps the front of its ). Then it pulls laid by the female survive to adult- them blend in to the habitat they the insect back to its mouth. Frogs’ hood. occupy. Frogs tend to be mainly shades are also sticky, but they are Frogs and toads are surprisingly of green and brown, similar to the green attached to the back of the mouth, so long-lived creatures—living up to 20 edges of ponds, lakes, rivers and frogs cannot extend their tongues as years in the wild. Toads have been streams. Toads tend to be colored by far as toads can. Frogs tend to make known to live more than 30 years in more earthy tones such as gray, brown, up the distance by ambushing prey captivity. red and yellow—similar to the leaf litter with an abrupt leap from a distance. in woodlands and dry grasses along They accurately catch an unsuspecting Frog and toad wetland borders. insect with their sticky tongue and differences Frogs and toads move differently. quickly consume it. Frogs differ from toads by having Their movement differs because they Frogs and toads also hibernate in smooth skin as compared to the have adapted differently to feeding and different habitats. Frogs usually “bumpy” or warty skin of toads. to avoiding predators. Frogs have long hibernate in water under or leafy Frogs need to keep their skin moist. legs adapted for leaping long distances debris at the bottom of streams or They tend to prefer more aquatic or when detected by a predator. Frogs also ponds. Toads hibernate in uplands by wet habitats. Toad skin tends to be have large webbed hind feet that assist using their back legs to dig deep drier and better suited to drier them with swimming and avoiding in leaf litter or soft soil safely habitats. This skin difference affects predators in the water. Conversely, below the frost line. where frogs and toads live. Frogs toads have short, stalky legs used for never stray too far from water or a hopping. Eastern American toad damp environment, and toads are Avoiding predators is not as much an The eastern American toad belongs not restricted to damp environments. issue with toads because they secrete a to the family Bufonidae. It is the In fact, toads have been observed in poison from glands in the skin on the largest of our three Pennsylvania toad about every habitat in Pennsyl- back when an animal bites them. Given species, reaching 4 inches in snout- vania. the quick reaction to the poison when a vent length. The eastern American All of our Pennsylvania toads are predator bites a toad (bad taste, nausea, toad is stout and squat in appearance, ground-dwelling animals. Although dizziness), most animals immediately with short, thick legs compared to the

www.fish.state.pa.us PennsylvaniaPennsylvania AnglerAngler && BoaterBoater •• March-AprilMarch-April 20052005 1717 long legs of frogs. Although they vary tor its large paratoid glands. Another greatly in color and pattern, they tend defensive posture is to inflate itself to Resources to be mainly rusty or brown in color, make it look too large for the predator with warts on the back and legs. One to swallow. or two warts occur in each of the Although the majority of potential largest dark spots. The eastern predators avoid an adult eastern American toad has a cranial ridge American toad because of learned behind its , which is a prominent behavior, many predators have adapted linear protrusion behind each that to their poisonous skin or have learned is either connected by one spur or not how to avoid it. touching the parotoid glands. The parotoid glands are large elongate bumps located on its back behind the The pickerel frog (Rana palustris) is Patches eyes. If a predator bites the toad, these classified in the family Ranidae, or true The Commission continues its glands secrete a distasteful poisonous frogs. Adult pickerel frogs reach about series of nongame species limited- white fluid that contains a , 3 inches in snout-vent length. The edition patches with an eastern which can affect a predator’s mouth, pickerel frog is characterized by a American toad patch and a pickerel and blood pressure. dominant brown or tan color with frog patch. Each patch sells for $4.71 Eastern American toads range from rectangular-shaped dark-brown spots plus 29 cents PA state sales tax for a (Manitoba) through the New that run down the length of the back total of $5.00. Include $2.00 ship- England states and south to central in two rows, and rows of spots that run ping and handling for each order. , west to eastern Oklahoma, along the body. It also has dark Kansas and . The eastern crossbars on the limbs and long hind Pennsylvania American toad is by far the most legs. Amphibians & common of the Commonwealth’s three Pickerel frogs are known to occur Reptiles toad species. It occurs in every from Canada south through northern Another excellent resource on Pennsylvania county and is thought to and eastern Georgia, west to the frogs, toads and Pennsylvania’s other be the most stable of the three toad eastern portion of , and north to reptiles and amphibians is the species. Eastern American toads are the Great Lakes. These frogs occupy a Commission’s book, Pennsylvania found in just about every habitat type variety of habitats, but they tend to Amphibians & Reptiles. The book in the Commonwealth where insects prefer damp meadows and slow- sells for $9.43 plus 57 cents PA state abound. moving streams, marshes or sales tax and $2.00 for shipping and Eastern American toads are active with low vegetation. Pickerel frogs handling (total of $12 for books sent both day and night, but they are most emerge from early in to PA addresses). active at night in the summer. They spring (late March). feed on , caterpillars, Even though this frog spends most Wall charts , beetles, spiders and a variety of of its time near stream or pond edges, The Commission’s four reptile flying insects. pickerel frogs are known to stray far and amphibian wall charts (frogs, In Pennsylvania, eastern American from aquatic habitat in search of turtles, salamanders and ) are toads hibernate deep beneath the soil insects in grassy upland meadows. For $3.77 for the set of four plus 23 cents or leaf litter from October to March. this reason, they are often referred to PA state sales tax and $2.00 for ship- They emerge early in spring and move as “meadow frogs.” ping and handling. to woodland (vernal) pools and Pickerel frogs have the same For all these items, contact: Edu- borders of streams, ponds, lakes and predators as toads. And like the cational Media Services, PA Fish & rivers to breed. American toad, but unlike its other Boat Commission, P.O. Box 67000, As a toad matures, it uses several relatives, the skin of the Harrisburg, PA 17106-7000. Or defense tactics to avoid being eaten. pickerel frog secretes a substance that from the Commission’s web site, Eastern American toads often “freeze” leaves the frog distasteful to many www.fish.state.pa.us, click on “The in place, not moving for some time predators. To avoid predators, the Outdoor Shop” and view or pur- when they detect a potential predator. pickerel frog takes several long leaps, chase patches and other resources Their helps them blend in often zigzagging its way to a nearby online. You may also use the prod- to their terrestrial background. When stream or other waterway, where it ucts & publications order form on a toad is threatened by a predator, it jumps into the water and hides under page 63 of this issue. “bows” its head and shows the preda- debris at the waterway bottom.

18 Pennsylvania Angler & Boater • March-April 2005 www.fish.state.pa.us