Animal Diversity Web

Ge­o­graphic Range

Opheodrys aes­tivus, com­monly known as the rough green snake, is found widely through­out the south­east­ern United States. It is found fre­quently as far north as south­ern New Jer­sey and can be found along the East Coast into the Florida Keys. The west­ern range stretches to cen­tral Ok­la­homa, Texas, and into north­ern Mex­ico. (Gray, 2005; Mitchell, 1994)

• Biogeographic Regions
• nearctic
  • native

Habi­tat

Rough green snakes are typ­i­cally found on for­est edges near ponds or lakes. Al­though they are ar­bo­real snakes, they for­age in dense veg­e­ta­tion along pond and lake shore­lines dur­ing the day. Their nights are spent coiled in the branches of trees. Rough green snakes choose perches based on dis­tance from shore­lines, height in branches, and thick­ness of the branch. Rough green snakes are most com­monly found in de­cid­u­ous trees, shrubs, hedgerows, and fields. (Mitchell, 1994; Plum­mer, 1981; Plum­mer, 1997a)

• Habitat Regions
• temperate
• terrestrial

• Other Habitat Features
• riparian

Phys­i­cal De­scrip­tion

Rough green snakes are small and thin. The dor­sal and lat­eral sur­faces are a uni­form green, the un­der­belly, chin and labial scales range from yel­low­ish-green to cream. Males and fe­males have no dif­fer­ences in color or pat­tern, but fe­males are larger in length and mass, while males have a longer tail length. Ju­ve­nile rough green snakes look like smaller adults, ex­cept they are lighter in color. Since these snakes are di­ur­nal and tend not to avoid the heat of the day, their peri­toneum is black and dense. This is be­lieved to be an adap­ta­tion that acts as an ul­tra­vi­o­let ra­di­a­tion shield, keep­ing these snakes from be­com­ing too hot. Fe­males range from 11 to 54 g in mass, with an av­er­age of 26.7 g, males are from 9 to 27 g, with an av­er­age of 16.3 g. Av­er­age lengths are 947 mm in fe­males and 892 mm in males. (Mitchell, 1994; Plum­mer, 1993)

• Other Physical Features
• heterothermic

• Sexual Dimorphism
• sexes alike
• female larger

• Range mass

  female: 11 male: 9 to female: 54 male: 27 g

  to oz

• Average mass

  female: 26.7 male: 16.3 g

  oz

• Average length

  female: 947 male: 892 mm

  in

De­vel­op­ment

When com­pared to other snakes, Opheodrys aes­tivus em­bryos are well-de­vel­oped upon egg lay­ing. This al­lows for a short in­cu­ba­tion pe­riod out­side of the fe­male, thus short­en­ing the span for preda­tors to eat the de­fense­less eggs. These eggs usu­ally range from 21.4 to 33.6 mm long, 9.3 to 11.1 mm wide, and 1.2 to 2.4 g. Upon hatch­ing, their length av­er­ages 128 to 132 mm and weigh 1.1 g (Mitchell, 1994). Most growth oc­curs in the first year of life. Fe­males grow at a faster pace and reach larger sizes than males. Ac­cord­ing to Plum­mer (1985), the growth of rough green snakes fol­lows the Von Berta­lanffy model, which al­lows any size snake to be aged rel­a­tively ac­cu­rately. How­ever, this model is more ac­cu­rate for younger snakes; error is pos­i­tively cor­re­lated with age. (Mitchell, 1994; Plum­mer, 1985a)

Re­pro­duc­tion

Rough green snakes re­pro­duce sex­u­ally with in­ter­nal fer­til­iza­tion. These snakes are promis­cu­ous, with males leav­ing al­most im­me­di­ately after cop­u­la­tion (Rich­mond, 1956). Courtship be­hav­ior of rough green snakes con­sists of vi­sual ori­en­ta­tion of males to­wards fe­males, ap­proach, body con­tact, and body align­ment. Some motor pat­terns that are dis­played dur­ing these stages are dor­sal crawl­ing, chin rub­bing, tail wav­ing, and head jerk­ing. Once aligned with a fe­male, a male be­gins with tail search cop­u­la­tory at­tempts in en­er­getic spurts fol­lowed by pe­ri­ods of mo­tion­less­ness. On av­er­age, align­ment is ac­com­plished in about 2:45 min­utes and the cop­u­la­tory se­quences av­er­age about 16:04 min­utes (Gold­smith, 1988). (Gold­smith, 1988; Mitchell, 1994; Rich­mond, 1956)

• Mating System
• polygynandrous (promiscuous)

Rough green snakes reach sex­ual ma­tu­rity at 21 months in males and 21 to 33 months in fe­males (Plum­mer, 1985). Al­though they breed every spring, fall mat­ings have been noted (Mitchell, 1994). The ges­ta­tion pe­riod can range from 5 to 12 weeks, de­pend­ing on tem­per­a­tures, and they typ­i­cally lay their eggs dur­ing June and July (Plum­mer, 1990). Clutch size is 3 to 12 soft-shelled eggs (Mitchell, 1994). Males first breed in the spring of their sec­ond year, usu­ally around 21 months. How­ever only half of fe­males par­tic­i­pate in breed­ing dur­ing their sec­ond spring, while the other half de­lays an ad­di­tional 12 months. Re­pro­duc­tively ma­ture fe­males can range from 360 to 400 mm snout-vent length, while sex­u­ally-ma­ture males av­er­age 300 mm (Plum­mer, 1985). (Gold­smith, 1984; Mitchell, 1994; Plum­mer, 1985a; Plum­mer, 1990a)

• Key Reproductive Features
• iteroparous
• seasonal breeding
• sexual
• oviparous

• Breeding interval

  Breeding occurs once yearly.

• Breeding season

  Rough green snakes breed in the spring.

• Range number of offspring

  3 to 12

• Average number of offspring

  6.2

• Range gestation period

  5 to 12 weeks

• Average gestation period

  6 weeks

• Range age at sexual or reproductive maturity (female)

  21 to 33 months

• Range age at sexual or reproductive maturity (male)

  20 to 21 months

• Average age at sexual or reproductive maturity (male)

  21 months

Fe­male rough green snakes near­ing ovipo­si­tion leave their usual ar­bo­real habi­tat to travel on the ground away from the shore­line. They seek out hol­lows in dead or liv­ing trees, de­cay­ing logs, under rocks or under boards in sandy soil. Such areas pro­vide suf­fi­cient mois­ture lev­els for egg-lay­ing. These lo­ca­tions are usu­ally about 30.0 m (+/- 9.0 m) away from the shore­line. After ovipo­si­tion, fe­males re­turn to the shore­line and re­sume her ar­bo­real post. Fe­males have no fur­ther con­tact with their eggs after hatch­ing (Plum­mer, 1990). (Plum­mer, 1990b)

• Parental Investment
• no parental involvement
• pre-fertilization
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female

Lifes­pan/Longevity

Sur­vival rates are not well known for ju­ve­nile rough green snakes. How­ever, adults have low sur­vivor­ship, which may partly ex­plain why these snakes be­come sex­u­ally ma­ture early and lay rather large clutches an­nu­ally. The main causes of mor­tal­ity are en­vi­ron­men­tal fac­tors (hot, dry con­di­tions) and pre­da­tion. This species has an av­er­age life ex­pectancy of 5 years, but they can reach up to 8 years. (Gold­smith, 1984; Plum­mer, 1985b; Plum­mer, 1997a; Plum­mer, 1997b)

• Average lifespan
  Status: wild

  8 years

• Typical lifespan
  Status: wild

  8 (high) years

• Average lifespan
  Status: wild

  5 years

Be­hav­ior

Rough green snakes are ar­bo­real and di­ur­nal. They spend their nights coiled on the far ends of tree branches near the shore­line (Plum­mer, 1997). Al­though ar­bo­real, they spend time on the ground for­ag­ing. They are seden­tary and will not bite as a de­fense, but rather flee into dense veg­e­ta­tion where they are cam­ou­flaged (Mitchell, 1994). Rough green snakes are ac­tive ex­cept in the cold win­ter months, usu­ally De­cem­ber to Feb­ru­ary, de­pend­ing on ge­o­graphic lo­ca­tion and tem­per­a­ture (Mitchell, 1994). The cold months are spent in hi­ber­na­tion. Rough green snakes are soli­tary, but there is a pos­si­bil­ity that they use com­mu­nal egg-lay­ing (Palmer & Braswell, 1976). (Mitchell, 1994; Palmer and Braswell, 1976; Plum­mer, 1997a)

• Key Behaviors
• arboreal
• diurnal
• sedentary
• hibernation
• solitary

• Average territory size

  201 m^2

Home Range

Rough green snakes have a home range of roughly 67 m in shore length, while only stray­ing about 3 m away from the shore it­self. Home ranges vary year to year by about 50 m (Plum­mer, 1997). They are not ter­ri­to­r­ial. (Mitchell, 1994; Plum­mer, 1997a)

Com­mu­ni­ca­tion and Per­cep­tion

Rough green snakes use their tongue to sense chem­i­cal cues. They also have keen eye­sight, al­low­ing them to eas­ily spot move­ment of prey. Mat­ing be­hav­iors in­volve tac­tile and vi­sual cues. (Cooper, 2007)

• Communication Channels
• chemical

• Perception Channels
• visual
• tactile
• vibrations
• chemical

Food Habits

Rough green snakes are in­sec­ti­vores, con­sum­ing crick­ets, grasshop­pers, other in­sects, and spi­ders (Mitchell, 1994). They ex­clu­sively use their ex­tra­or­di­nary vi­sion to hunt live prey. Even a slight move­ment of a leg or an­ten­nae is suf­fi­cient to draw the at­ten­tion of these snakes to the lo­ca­tion of their prey (Gold­smith, 1986). Ac­cord­ing to Gold­smith (1986), dur­ing the ini­tial phase of their ap­proach, these snakes use fast and ir­reg­u­lar move­ments, but they slow down as they fur­ther ap­proach their prey. When rough green snakes are about 3 cm from prey, they as­sume spring-like curves with their body, fol­lowed by a straight­en­ing of the body, al­low­ing the snake to pro­pel its head to­ward the prey, strik­ing ei­ther at the head or tho­rax. Rough green snakes some­times raise their head above the sub­strate im­me­di­ately upon strik­ing in order to get prey away from any­thing that may aid their es­cape. Prey is worked fur­ther into the mouth and swal­lowed by move­ments of the jaw. Prey is usu­ally swal­lowed head first. (Gold­smith, 1986; Mitchell, 1994)

• Primary Diet
• carnivore
  • insectivore

• Animal Foods
• insects
• terrestrial non-insect arthropods

Pre­da­tion

Many an­i­mals prey up on these snakes, in­clud­ing larger snakes, birds, do­mes­tic cats, and even some spi­ders (Plum­mer, 1990; Mitchell, 1994). Their only de­fense mech­a­nism is cam­ou­flage. (Mitchell, 1994; Plum­mer, 1990a)

• Anti-predator Adaptations
• cryptic

• Known Predators

  • loggerhead shrikes (Lanius ludovicianus)
  • hawks (Buteo species)
  • domestic cats (Felis catus)
  • bluejays (Cyanocitta cristata)
  • kingsnakes (Lampropeltis getulus)
  • racers (Coluber constrictor)

Ecosys­tem Roles

Rough green snakes are a source of prey for larger snakes, birds, and other small preda­tors. There are a few known par­a­sites that af­fect rough green snakes. They are in­fected oc­ca­sion­ally with Cryp­tosporid­ium species, which af­fects the gas­troin­testi­nal tract, caus­ing ep­ithe­lial necro­sis. (Brower and Cran­field, 2001; Plum­mer, 1981)

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Al­though not com­mon pets, do­mes­ti­ca­tion of these snakes has be­come in­creas­ingly pop­u­lar be­cause they are easy to care for. (Plum­mer, 1981)

• Positive Impacts
• pet trade

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

There are no known ad­verse ef­fects of Opheodrys aes­tivus on hu­mans.

Con­ser­va­tion Sta­tus

Rough green snakes are listed as a species of least con­cern. Due to their ap­par­ent pop­u­la­tion sta­bil­ity, no con­ser­va­tion ef­forts are planned. (Plum­mer, 1985b)

• IUCN Red List

  Least Concern
  More information

• IUCN Red List

  Least Concern
  More information

• US Federal List

  No special status

• CITES

  No special status

• State of Michigan List

  No special status

Con­trib­u­tors

Kaelin Cre­ange (au­thor), Rad­ford Uni­ver­sity, Karen Pow­ers (ed­i­tor), Rad­ford Uni­ver­sity, Tanya Dewey (ed­i­tor), Uni­ver­sity of Michi­gan-Ann Arbor.

Ref­er­ences

Brower, A., M. Cran­field. 2001. Cryp­tosporid­ium sp.-As­so­ci­ated En­teri­tis with­out Gas­tri­tis in Rough Green Snakes. Jour­nal of Zoo and Wildlife Med­i­cine, Vol. 32, No. 1: 101-105.

Cooper, W. 2007. El­e­vated tongue-flick­ing rate to cricket sur­face chem­i­cals by the arthro­po­di­v­o­rous rough green snake Opheodrys aes­tivus. AM­PHIBIA-REP­TILIA, Vol­ume: 28 Issue: 3: 413-417.

Gold­smith, S. 1988. Courtship Be­hav­ior of the Rough Green Snake, Opheodrys aes­tivus (Col­u­bri­dae: Ser­pentes). The South­west­ern Nat­u­ral­ist, Vol. 33, No. 4: 473-477.

Gold­smith, S. 1984. As­pects of the Nat­ural His­tory of the Rough Green Snake, Opheodrys aes­tivus (Col­u­bri­dae). The South­west­ern Nat­u­ral­ist, Vol. 29, No. 4: 445-452.

Gold­smith, S. 1986. Feed­ing Be­hav­ior of an Ar­bo­real, In­sec­tiv­o­rous Snake (Opheodrys aes­tivus) (Col­u­bri­dae). The South­west­ern Nat­u­ral­ist, Vol. 31, No. 2: 246-249.

Gray, B. 2005. The Ser­pent's Cast - A Guide to the Iden­ti­fi­ca­tion of Shed Skins from Snakes of the North­east and Mid-At­lantic States. Lans­ing, Michi­gan: ECO Her­peto­log­i­cal Pub­lish­ing & Dis­tri­b­u­tion.

Mitchell, J. 1994. The Rep­tiles of Vir­ginia. Wash­ing­ton and Lon­don: Smith­son­ian In­sti­tu­tion Press.

Palmer, W., A. Braswell. 1976. Com­mu­nal Egg Lay­ing and Hatch­lings of the Rough Green Snake, Opheodrys aes­tivus. Jour­nal of Her­petol­ogy, Vol. 10, No. 3: 257-259.

Plum­mer, M. 1990. Nest­ing Move­ments, Nest­ing Be­hav­ior, and Nest Sites of Green Snakes (Opheodrys aes­tivus) Re­vealed by Ra­dioteleme­try. Her­peto­log­ica, Vol. 46, No. 2: 190-195.

Plum­mer, M. 1983. An­nual Vari­a­tion in Stored Lipids and Re­pro­duc­tion in Green Snakes (Opheodrys aes­tivus). Copeia, Vol. 1983, No. 3: 741-745.

Plum­mer, M. 1985. De­mog­ra­phy of Green Snakes (Opheodrys aes­tivus). Her­peto­log­ica, Vol. 41, No. 4: 373-381.

Plum­mer, M. 1987. Ge­o­graphic Vari­a­tion in Body Size of Green Snakes (Opheodrys aes­tivus). Copeia, Vol. 1987, No. 2: 483-485.

Plum­mer, M. 1985. Growth and Ma­tu­rity in Green Snakes (Opheodrys aes­tivus). Her­petolig­ica, 41: 28-33.

Plum­mer, M. 1981. Habi­tat Uti­liza­tion, Diet and Move­ments of a Tem­per­ate Ar­bo­real Snake (Opheodrys aes­tivus). Jour­nal of Her­petol­ogy, Vol. 15, No. 4: 425-432.

Plum­mer, M. 1990. High Pre­da­tion on Green Snakes, Opheodrys aes­tivus. Jour­nal of Her­petol­ogy, Vol. 24, No. 3: 327-328.

Plum­mer, M. 1997. Pop­u­la­tion Ecol­ogy of Green Snakes (Opheodrys aes­tivus) Re­vis­ited. Her­peto­log­i­cal Mono­graphs, Vol. 11: 102-123.

Plum­mer, M. 1997. Speed and En­durance of Gravid and Non­gravid Green Snakes, Opheodrys aes­tivus. Copeia, Vol. 1997, No. 1: 191-194.

Plum­mer, M. 1993. Ther­mal Ecol­ogy of Ar­bo­real Green Snakes (Opheodrys aes­tivus). Jour­nal of Her­petol­ogy, Vol. 27, No. 3: 254-260.

Plum­mer, M., H. Snell. 1988. Nest Site Se­lec­tion and Water Re­la­tions of Eggs in the Snake, Opheodrys aes­tivus. Copeia, Vol. 1988, No. 1: 58-64.

Rich­mond, N. 1956. Au­tumn Mat­ing of the Rough Green Snake. Her­peto­log­ica, Vol. 12, No. 4: 325.

Rich­mond, N. 1952. Opheodrys aes­tivus in Aquatic Habi­tats in Vir­ginia. Her­peto­log­ica, Vol. 8, No. 2: 38.

Tin­kle, D. 1960. A Pop­u­la­tion of Opheodrys aes­tivus (Rep­tilia: Squa­mata). Copeia, Vol. 1960, No. 1: 29-34.