Grey Tree Frog

Introduction

For this week’s post I wanted to write about an amphibian that was the primary reason I wanted to work with animals. This species of amphibian has always been in my backyard no matter where I lived. This week’s post is on the grey tree frog.

 Matt Bell 2018

Grey Tree Frogs in my Backyard

Since I was a small child living in Pittsburgh the grey tree frog has been part of my life. I remember when I was five or six searching for critters in the yard of my Pittsburgh home. During this search I found a gray frog clinging to the branch of a tree. I still remember grabbing it and being shocked when it started to cling to my arm. Being a young kid, and never seeing a creature like this I thought I had discovered an alien frog. I raced inside to show my mom my finding. She did not know what kind of frog it was, but assured me it was not an alien. Determined to figure out what type of frog it was I search my reptile and amphibian field guide and discovered the alien frog was actually a grey tree frog.

Fast forward a few years, during which I was living in Indiana. The first spring there I found a grey tree frog and this time kept him as a pet. I kept him in a 10 gallon aquarium, and fed him insect I would capture during my outdoor explorations. At the end of summer I released him back into the wild. 

Today, I still see grey tree frogs almost yearly. Most of the time I find them in my small forest or clinging to one of my window on a raining day. At a nature center I volunteer at I get to work with the grey trees frog they have weekly.

Grey Tree Frog Fast Facts

• Female gray tree frogs are larger than males, averaging in size between 1.5 to 2.2 inches. The average size of a male gray tree frog is 1.25 to 2 inches.

•  Grey tree frogs help their ecosystem by eating large amounts of flies, gnats, and mosquito. Grey tree frogs also act as food source for many larger predatory species. 

• Male grey tree frogs are very territorial, and will fight to defend their territory.

• Fight between male frogs can last 30 to 90 seconds and involves head butting, kicking, and shoving.

• Gray tree frogs normally live between 7 and 9 years.

• Grey tree frogs can change the color of their skin. Skin shades include grey, brown, green, and even black. The color of the frog changes in response to activities and the environment around them.

• Grey tree frogs also have bright orange and yellow marking under their legs. Scientists believe these bright marking are used to warn predators not to attack.

Hibernation

During the winter months grey tree frogs hibernate beneath rocks, bark, or on the forest floor. When the gray tree frog becomes frozen the blood and water inside the frog freezes, and organs like the heart and lung spot functioning. Despite these factors that would kill a human in the spring the gray tree frogs thaws out and hopes away.
        The Gray tree frogs survives freezing by creating a large amount of glycerol. This eventually turns to glucose, which travels through the frog’s cells. The glucose acts as a type of anti-freeze that prevents ice crystals from forming in the frogs cells and major organs. If ice crystals were to form the frogs cells would be torn apart and organs would be permanently damaged.

 

Photo Credit Fredlyfish4

Reproduction

Grey tree frogs emerge from hibernation in early spring. During this time the male frogs begin their mating calls. The mating calls normally occur between April and August, although most mating takes place during the spring months. A female will begin the mating process by touching the male frog and rotating 90 degrees. The male frog grabs the female frog with his front legs, then the magic happens. Mating occurs while the frogs are floating in the water. The female will lay between 1,000 and 2,000 eggs, which are fertilized by the male frog. The eggs are released in small cluster.
        Tadpoles hatch between three and seven days, factors like water temperature effect how long it takes the eggs to hatch. Around an hour before hatching tadpoles release fluid to help break down the egg walls. Water temperature also effects the metamorphosis of tadpoles. It takes the tadpoles between 45 to 65 days to develop into frogs, and two years to become sexually mature.

Diet

The gray tree frog is a nocturnal hunter who locates food in shrubs and trees. The tree frogs will often leap from branch to branch to capture prey. A gray tree frogs main diet is made up of insects like beetles, ants, flies, crickets, and grasshoppers. In some causes gray tree frogs will eat smaller frogs and their own young! When in tadpole form gray tree frogs eat organic detritus and algae. “The tree frogs I work with at the nature center eat crickets dusted with calcium supplement.”  

 

Matt Bell 2018

Predators

The adult grey tree frog is preyed upon by species of snakes, birds, small mammals, giant water bugs, and even larger species of frogs. Two frog species that will eat grey tree frogs are green and bullfrogs. Tadpoles are mainly eaten by fish and larger amphibian larvae, like the larvae of the tiger salamander. 

Poison

Gray tree frogs create toxic secretions from their skin. If these secretions gets into a person’s nose, eyes, month, or open cuts it can cause extreme discomfort. The toxin is not deadly, but always wash your hands after handling a grey tree frog. 

How to Grey Tree Frogs Stick to Walls? 

The toes of the grey tree frog have round disks. These disks act as suckers that assist the frog in climbing branches and leaves. The round disks also create a type of sticky adhesive fluid that further assists the frog in climbing. The toes of the gray tree frog can curl with helps the frog move grasp thin twigs.  

Matt Bell 2018

Conclusion

The grey tree frog is one of my favorite species of amphibians on earth. Everyone of my homes have had grey tree frogs in there backyards. Join me next time as we explore wildlife in my backyard and other nature topics. 

References and Additional Resources 

Animal Diversity Web. (2014). Gray Treefrog. Retrieved from http://animaldiversity.org/accounts/Hyla_versicolor/

New Hampshire PBS. (2017). Gray Treefrog. Retrieved from http://www.nhptv.org/natureworks/graytreefrog.htm

Science Museum of Minnesota. (2018). Gray Treefrog. Retrieved from https://www.warnernaturecenter.org/animals/treefrog

Smithsonian’s National Zoo. (N.D.). Gray tree frog. Retrieved from https://nationalzoo.si.edu/animals/gray-tree-frog

Photo Credit and References

Fredlyfish4 - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=27285910

LA Dawson at en.wikipedia (see upload page) - Originally from en.wikipedia., CC BY-SA 2.5, https://commons.wikimedia.org/w/index.php?curid=2446882