A Guide to the Amphibians
and Reptiles of California

Frog and Toad Behavior and Natural History

Click on a picture for a larger view

Frogs Eating	Movement	Sounds	Reproduction	Predators
Camouflage	Clustering	Toes	Miscellaneous Observations

This is the fun stuff - pictures and videos that illustrate interesting behaviors and features of some of the frogs and toads shown throughout this web site. Follow the links on the name of each species to find more pictures and information about it. I will keep adding more pictures and videos as I get them.
The Life Cycle of the California Toad

This short video shows the life cycle of the California Toad, from the late winter breeding season when frenzied males call and compete and pair up with females who lay long strings of eggs, to tiny black tadpoles just emerged from the eggs then developing and forming huge feeding masses, to the tiny toads, recently-transformed from tadpoles, massing together around the pond edge then dispersing on their own, to an adult toad moving about on its own, as it will remain until the next breeding season. To see more video of each stage, click on the thumbnails below.




Frogs and Toads Eating

A large adult California Red-legged Frog sits still at the edge of a pond under some vegetation until a grasshopper lands nearby when it explodes into action, grabbing the insect on the underside of its long sticky pink tongue.	The same California Red-legged Frog eating grasshoppers in slow motion so you can see it's big tongue in action.	Sitting at night in the Arizona desert next to a breeding pond where other Lowland Burrowing Treefrogs and Couch's Spadefoots are calling, a frog repeatedly snaps up bugs with its big pink tongue, which you can seen when the action is slowed down a few times.

This night video shows a Black Toad lunging with its sticky tongue extended, trying to catch something to eat. First in real time, then repeated in slow motion, then we return to real time.	In this short night video, a male Sonoran Green Toad stops calling and leaps after a flying insect that is attracted to the video lights. Catching it with his tongue, he backs up and swallows it. In real time, then repeated in slow motion.	This short video shows several Chiricahua Leopard Frogs sitting around a pond and jumping after flying insects. The frogs mostly sat and waited for food to come to them, but occasionally they crawled or hopped quickly to catch something. Watch carefully, because they jump so quickly that it's hard to see what is happening. The video is repeated at the end in slow motion so you can see their huge mouths and tongues in action.

This video shows Western Spadefoot tadpoles swimming and feeding in a murky rain puddle. The have to eat as much as possible so they will grow large enough to transform into terrestrial spadefoots before the puddle completely dries up.	This video of Sierran Treefrog tadpoles shows how tadpoles move using their long tail, and feed with their mouth on plant material on the surface of the water.	This video shows some huge American Bullfrog tadpoles swimming and feeding.

In this short video, an American Bullfrog sitting on the edge of a small pond tries to grab an insect with its tongue and fails, but succeeds on the second try, then jumps into the water to finish it off.	Adult American Bullfrog eating a lesser goldfinch that came to drink in an artificial pond in Tehama County. © Lori Grennan
Frog and Toad Movement
While frogs often use the strength of their muscular hind legs to hop long distances, toads generally move by crawling and using short hops. Take a look at the feeding videos above to see frogs and toads lunging and leaping after food.

This video shows some Southern Mountain Yellow-legged Frogs in a quiet mountain creek hopping, swimming, and creeping up and lunging after food.	This video shows a California Toad moving both by crawling and by hopping.	This video shows several Black Toads moving around at night in shallow water, hunting for food.

This video shows several Amargosa Toads hopping, swimming, and crawling around at night.	This video shows several Cascades Frogs along a creek, some of them hopping and swimming.	This video shows a few American Bullfrogs including some hopping, diving, and swimming.

	This video shows tiny Red-spotted Toads that have just transformed from tadpoles, hoping across an algae mat on a pond.
Frog and Toad Sounds
During the breeding season, or sometimes whenever rains have filled breeding pools, males of most species of frogs and toads typically set up a territory near good egg-laying locations, and make a call unique to its species. Frogs usually call at night, but in some places where it gets very cold at night, they call during the day. These calls serve both to attract females and to let other male frogs know that they have claimed a particular territory. Frogs call by exhailing air and using the larynx muscles in the throat to produce a specific sound. The sound is amplified by a vocal sac or sacs - thin membranes of skin under the throat or at the corners of the mouth, that look like a balloon when they are full of air. Some calls are weak, others are extremely loud. A few frogs call from underwater, and their calls usually cannot be heard above the water. You can listen to the calls of many of the frogs and toads shown on this website, and watch some of them calling on video. Here is a list of species on this site that you can listen to. Follow the links to listen and to find videos to watch a frog calling. Here is a chart of the calls of all of California Frogs and Toads, with links to short sounds and videos.

Canyon Treefrog	Great Plains Toad This toad's vocal sac extends out and then straight up.	California Treefrog

Couch's Spadefoot Calling while floating on water	Foothill Yellow-legged Frogs have small vocal sacs which produce a weak sound. They live around fast-moving noisy streams which can cover up their calls, so they also call from underwater, as seen on the right.

Typically, this species calls from the edge of the water at night, but this short video shows a male Northern Pacific Treefrog calling while floating on a pond during daylight.	Northern Red-legged Frog calling underwater in Humboldt County, CA. I recorded this frog with an underwater microphone. You can hear it here.	This video shows a Rio Grande Leopard Frog calling at night, using his throat sack as well as pouches on the side of the neck to produce a variety of sounds. Another Rio Grande Leopard frog joins in and they are both accompanied by an American Bullfrog.

Lowland Burrowing Treefrog The vocal sacs of this frog extend all the way around the mouth.	Great Basin Spadefoot	Western Green Toad

New Mexico Spadefoot Calling while floating on water	Squirrel Treefrog	Houston Toad

A male California Toad picked up out of the breeding pond makes the release call, then swims away.	In this video, you can see a Boreal Toad giving a release call after he is picked up and gently grasped across the back. (It may sound like this toad is suffering, but it was not harmed. This is a warning call, the same one he makes when another male toad comes into his territory or climbs onto his back.)	An adult male Sierran Treefrog makes a one-part call while floating on the water on a sunny afternoon in Contra Costa County.

Three adult male Sierran Treefrogs make their advertisement call one afternoon in early March in Contra Costa County.	In this short video we see three adult male Sierran Treefrogs make their encounter call. These calls were elicited by making a raspy noise near the frogs as they were sitting on the water in calling position. The call of each frog is slightly different.	A male Sierran Treefrog makes a few advertisement calls, until a second frog between him and the camera, makes a raspy trilled encounter call. The first frog responds with his encounter call, but when the second frog continues, he then turns to face his aggressor and charges toward him, continuing to make his encounter call. The second frog changes his call to a faster one part call. Finally they both stop, and the first frog sucks in his throat sac and dives underwater.

A male Baja California Treefrog calls at night as part of a chorus of frogs in Kern County. He starts with the two-parted call, then speeds up a bit slurring the two parts together into what is almost a one-part call which he then alternates with the two-parted call.	American Bullfrogs are a pest in the West, where in some areas they are very abundant, especially with frogs that are not yet full-grown adults.These sub-adults and juveniles usually chirp and jump into the water or onto the shore when they are frightened. In this short video, hundreds of them put on a showwith a chorus of chirps accompanied by splashing and skipping across the water.
Reproduction
Males typically call until a female comes into their territory and then they quickly jump onto the back of the female and hold on. Males have thicker and stronger front legs than females to help them hold on, and they even develop special grasping pads, called Nuptial Pads, on one or more fingers of each hand to help their grasp. This behavior is called Amplexus. Males can get so excited that they will sometimes grab onto other males, other species of frogs, and even other animals, such as fish. Sometimes several males go after the same female, forming a ball of males with a female in the middle. This can be dangerous to the female is she cannot get to the surface to breathe. The male stays on the female until she lays her eggs and he fertilizes them.

A nuptial pad on front foot of an adult male Boreal Toad.	Great Plains Toads	Gulf Coast Toads

Columbia Spotted Frogs	Sierra Yellow-legged Frogs	Couch's Spadefoot

American Toads		This video shows a male and a female Western Spadefoot in amplexus underwater in a breeding area of a rocky creek bed in San Joaquin County. You can also see some eggs by the pair and floating nearby. (The first shot is of the female after the male left her.)

Yosemite Toads in amplexus with the female depositing her eggs	Congregation of breeding adult California Toads © Joyce Gross	Male California Toads searching for females will sometimes go after anything that moves. These California Toads appear to be trying to amplex a catfish. © Andy Hatch

These misguided California Toads are attempting to breed with a dead toad. It's possible they found a dead female, but its also possible they suffocated or drowned her in their agressive competition to amplex her. © Mark Gary	Red-spotted Toads	Cascades Frogs

These videos showbreeding behavior at the shallow outlet of a pond in Contra Costa County where at least 8 solo males and 10 pairs in amplexus were observed in the area.

This video shows some of the sounds and activities of Black Toads on the breeding grounds.	In this video, a group of male Black Toads thrash around in the water trying to wrestle away a female away from another male.	A short video of non-stop ultimate toad-fighting action with a gang of Black Toads trying to steal away females from other males, chasing them around the pond.

	This video shows a Northern Red-legged Frog breeding habitat with eggs.
Sometimes Male frogs and toads grab onto a female or even a male of the wrong species, as you can see below.

This Houston Toad is in amplexus with the wrong species - a Gulf Coast Toad.	These California Red-legged Frogs are in amplexus with California Toads that share their ponds and breed at the same time.
Camouflage

Canyon Treefrogs are colored and patterned to match the rocks along the creeks where they live. They also hunch themselves over, hiding their legs, so they look like little clumps of rock. This camouflage helps them hide from predators.	Canyon Treefrogs, barely visable at a distance on a large boulder.	This video shows a few Canyon Treefrogs on rocks along a creek.

Several adult California Treefrogs blend in perfectly with the creek-side granite rocks they sit on. © Mark Gary
Clustering and other Interactions
Sometimes frogs congregate into groups. One study tested whether some juvenile toads gathered together for protection or to keep from getting too dry, or desiccating, and concluded that the clustering reduced desiccation.

Chiricahua Leopard Frogs These frogs gradually gathered into small and large groups at the edge of a pond, even climbing up onto the backs of other frogs.		Chiricahua Leopard Frogs This video shows frogs diving into the water, and later a number of frog clusters.

In this short video, American Bullfrogs sitting around a crowded pond group together and interact with each other, making what appear to be territorial sounds.	A congregation of Sierra Nevada Yellow-legged Frogs. These frogs were discovered on the south-facing slope of a barely ice-free alpine lake (11,000 ft.). They are covered with pollen, wind-blown from lower altitudes, which coated the area. © Ceal Klingler
Toe Pads for Climbing
Some frogs have special pads on their toes that act like suction cups to help them climb steep surfaces, even glass.

California Treefrog	Baja California Treefrog	Northern Pacific Treefrog

Green Treefrog climbing on class	Baja California Treefrog climbing on class	Mexican Treefrog climbing on class
Predators

Bullfrogs are an invasive species that consume many native species, so it is nice to see this adult Diablo Range Gartersnake eating a Bullfrog tadpole in Santa Clara County. Although eventually the snake regurgitated the tadpole. It was probably too big for it to eat. © Chad Lane		This Valley Gartersnake was found attempting to eat a non-native Leopard Frog in a suburban backyard. (The frog survived, but died later.) © Stephanie Mastriano

A Western Black-necked Gartersnake eating a Chiricahua Leopard Frog. After these pictures were taken, the snake swam across a small pool and finished swallowing the frog, as you can see in the video of this below.

A tiny recently-metamorphosed spadefoot hops around the edge of its birth puddle trying to shake off a predatory insect larva which has grasped onto its tail.	This video shows the Western Black-necked Gartersnake seen above, swallowing a Chiricahua Leopard Frog, back legs first. The snake swims across the creek to finish eating against the bank, then swims into some roots to hide. The video has been severely edited to keep it short. The entire swallowing activity, after I discoverd the snake with the frog half eaten, took about ten minutes.	"At the end of the island I noticed a small green frog. He was exactly half in and half out of the water, looking like a schematic diagram of an amphibian, and he didn't jump.... He was a very small frog with wide, dull eyes. And just as I looked at him, he slowly crumpled and began to sag. The spirit vanished from his eyes as if snuffed. His skin emptied and drooped; his very skull seemed to collapse and settle like a kicked tent. He was shrinking before my eyes like a deflating football. I watched the taut, glistening skin on his shoulders ruck, and rumple, and fall. Soon, part of his skin, formless as a pricked balloon, lay in floating folds like bright scum on top of the water: it was a monstrous and terrifying thing. I gaped bewildered, appalled. An oval shadow hung in the water behind the drained frog; then the shadow glided away. The frog skin bag started to sink." -Annie Dillard in "Pilgrim at Tinker Creek", describing a giant water bug preying on a frog.
Miscellaneous Frog and Toad Observations

Frogs shed their skin just like snakes and lizards. In this short video you can see the skin pulled from the front toes and rear legs of a Chiricahua Leopard Frog and swallowed. The frog uses all four of its legs to pull the old skin off and push it towards its mouth. The mouth is opened and closed to pull the skin into the mouth. This one minute video was cut down from about five minutes, but the shedding took much longer.	Spadefoots and some toads have hardened spades on the backs of their feet. These spades help them dig underground. This picture shows the small black spade on one of the hind feet of a Great Basin Spadefoot	Spadefoots spend most of their lives buried in mud or sand. This short video shows a Great Basin Spadefoot digging into sandy soil and burying itself. © Julie Nelson

This Great Basin Spadefoot is using its nictitating membrane, a translucent membrane, also called a third eyelid, to moisten its eye. © Ceal Klingler	This frightened Rio Grande Leopard Frog pulled its front hands in front of its eyes, maybe to protect them from attack.

This juvenile treefrog from San Mateo County has a deformed fifth leg. © Rory Doolin. Because of their thin permeable skin, amphibians are one of the first indicators of environmental disturbances, some of which can cause malformations as we see here.	Cascades Frogs live high in the mountains and have a high tolerance for cold. They emerge from hibernation and breed as the snow and ice is melting. This frog is sitting at the edge of the ice covering a mountain pond, while other frogs call and breed nearby.	Spadefoot tadpoles hatched in shallow rain pools need to grow and transform quickly when there is no rain and the pools evaporate. Here you can see tadpoles in the water, recently-metamorphosed tailed juveniles on the land and in the water, and some views of a shallow rain pool as it dries up.

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