Diadophis punctatus

Ringneck snakes are common snakes occurring throughout eastern and central North America. Their range extends from Nova Scotia, southern Quebec, and Ontario to south-central Mexico, covering the entire eastern seaboard except for areas along the gulf coasts of south Texas and northeast Mexico. The range extends laterally to the Pacific coast except for large areas in drier regions of the western United States and Mexico.

Biogeographic Regions: nearctic (Native )

The range of this species extends from the Pacific coast to the Atlantic coast of North America (Conant and Collins 1991, Stebbins 2003). The northern limit of the more or less continuous portion of the range reaches Nova Scotia, southern Quebec, southern Ontario in Canada, Minnesota, southeastern South Dakota, eastern Nebraska, southeastern Colorado, and Arizona in the United States. The southern limit extends to San Luis Potosi (Mexico), the Gulf Coast of the United States, and southern Florida. The species also occurs disjunctly in western North America in eastern Washington, eastern Oregon, Idaho, Nevada, Utah, and Arizona, and it ranges from southern Washington through western Oregon and throughout much of California (except the Central Valley and deserts) into northwestern Baja California, including Islas Todos Santos and San Martin along the Pacific Coast (Grismer 2002). This species has been introduced on Grand Cayman Island (probably via ornamental plants from southern Florida), but it is unknown whether or not the species is established there (Schwartz and Henderson 1991).

Ringneck snakes are common snakes occurring throughout eastern and central North America. Their range extends from Nova Scotia, southern Quebec, and Ontario to south-central Mexico, covering the entire eastern seaboard except for areas along the gulf coasts of south Texas and northeast Mexico. The range extends laterally to the Pacific coast except for large areas in drier regions of the western United States and Mexico.

Biogeographic Regions: nearctic (Native )

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: (>2,500,000 square km (greater than 1,000,000 square miles)) The range extends from the Pacific coast to the Atlantic coast of North America (Conant and Collins 1991, Stebbins 2003). The northern limit of the more or less continuous portion of the range reaches Nova Scotia, southern Quebec, southern Ontario, Minnesota, southeastern South Dakota, eastern Nebraska, southeastern Colorado, and Arizona. The southern limit extends to San Luis Potosi (Mexico), the Gulf Coast of the United States, and southern Florida. The species also occurs disjunctly in western North America in eastern Washington, eastern Oregon, Idaho, Nevada, Utah, and Arizona, and it ranges from southern Washington through western Oregon and throughout much of California (except the Central Valley and deserts) into northwestern Baja California, including Islas Todos Santos and San Martin along the Pacific Coast (Grismer 2002). This species has been introduced on Grand Cayman Island (probably via ornamental plants from southern Florida), but it is unknown whether or not the species is established there (Schwartz and Henderson 1991).

Continent: Middle-America North-America Caribbean
Distribution: SE Canada (incl. Nova Scotia, New Brunswick, Ontario, Quebec) USA (California, Oregon, Illinois, New Mexico, Texas, Oklahoma, Kansas, Nebraska, SE/NE Minnesota, SE Colorado, SE Idaho, Utah, SE South Dakota, Iowa, Missouri, Arkansas, Louisiana, Mississippi, Alabama, Georgia, Florida, South Carolina, North Carolina, Virginia, West Virginia, Kentucky, Indiana, Illinois, Wisconsin, Ohio, Maryland, Pennsylvania, New Jersey, Michigan, New York, Rhode Island, Connecticut, Massachusetts, S New Hampshire, S Vermont, S Maine)  Mexico (incl. Aguascalientes), Cayman I  
Type locality: Carolina; restricted to Charleston, South Carolina, by Schmidt, 1953  acricus: Florida;
Type locality: Big Pine Key  amabilis: California;
Type locality: San Jose, California (see Stejneger & Barbour, 1943)  arnyi: Wisconsin, Kansas, Arkansas, Oklahoma;
Type locality: Hyatt, Anderson County, Kansas  docilis: Texas;
Type locality: between Rio San Pedro or Devil’s River and Comanche Spring, Texas  edwardsii: Wisconsin, Ohio, Kentucky, Pennsylvania, etc.;
Type locality: Pennsylvania  modestus: California;
Type locality: California (see Stejneger & Barbour, 1943)  occipitalis: South Carolina;
Type locality: designated as “Charleston, South Carolina” (see Schmidt, 1953)  pulchellus: California;
Type locality: El Dorado County, California (see Stejneger & Barbour, 1943)  punctatus: South Carolina, Georgia, Florida;
Type locality: Carolina (in Linnaeus, 1766), but given as “Carolina and Eastern Gulf States” by Stejneger & Barbour (1943), and restricted to “Charleston, South Carolina” by Schmidt (1953)  regalis: Mexico (Sonora);
Type locality: Sonora, Mexico  stictogenys: Illinois, Arkansas;
Type locality: designated as “southern Illinois” (see Schmidt, 1953: 183)  texensis: Louisiana, Texas;
Type locality: “New Orleans to Galveston”

The backside, or top, of ringneck snakes can be blue/gray, light brown, or greenish-gray, but it is always a solid color, except for a gold ring around the neck. The ring may not be complete on all animals and may be absent in some. The belly is yellowish-orange, but in some regions may be more orangish-red towards the end. In some regions there are black spots on the belly.

The scales on the back are smooth and the anal plate is divided. Average length ranges between 25 and 38 cm, but some can reach up to 46 cm. When ringneck snakes are born the have the same coloration as adults. Adult females are generally longer than males, and both males and females shed their skin throughout the year.

Range length: 25.5 to 46 cm.

Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry

Sexual Dimorphism: female larger

The dorsum of ringneck snakes varies among subspecies from blue-gray to light brown to greenish-gray, but it is always solid, except for a distinctive golden ring around the neck. The ring may be interrupted or, in the cases of the regal ringneck snakes (D. punctatus regalis) and key ringneck snakes D. punctatus acricus, may appear only as a trace or be completely absent. The abdomen is orange-yellow, but western and extreme southern subspecies show a change in color to orange-red toward the posterior. The presence and configuration of black spots on the abdomen can be used to distinguish subspecies.

Eastern subspecies have 15 scale rows at the anterior end; western subspecies have 17. Scales are smooth and the anal plate is divided. The species has a length of 25 to 38 cm, except D. punctatus regalis, which measures 38 to 46 cm. Newborn snakes have the same markings and coloration as adults. Generally speaking, adult females are longer than adult males. Molting occurs in all months of the year.

Range length: 25.5 to 46 cm.

Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry

Sexual Dimorphism: female larger

Length: 76 cm

Ringneck snakes prefer areas with good hiding spaces, but they are found in many different habitats. Damp soil and temperatures between 27 and 29 degrees Celsius are best. Northern and western subspecies prefer to hide under stones or loose bark from dead trees. They are often found in open woodlands near rocky hillsides. Southern subspecies usually stay in wetter areas, like swamps, damp forests, or riparian woodlands.

Habitat Regions: temperate ; terrestrial

Terrestrial Biomes: savanna or grassland ; chaparral ; forest

Wetlands: marsh

Habitat and Ecology

Systems

• Terrestrial

Areas with abundant hiding places are preferred by all subspecies of D. punctatus but, beyond that, they occur in a wide variety of habitats. Gently moistened soil and 27 to 29 degrees Celsius provide optimal conditions. Northern and western subspecies prefer coverage under stones or under the loose bark of dead trees, and are often found in open woodlands near rocky hillsides. Southern subspecies tend to stay in conspicuously wet locales, such as swamps, damp forests, or riparian woodlands.

Habitat Regions: temperate ; terrestrial

Terrestrial Biomes: savanna or grassland ; chaparral ; forest

Wetlands: marsh

Comments: This snake occurs in forests, woodlands, grassland, chaparral, and riparian corridors in arid regions (Stebbins 2003). Habitats are moist, at least seasonally. One or multiple individuals often are found near abandoned buildings and in junk piles in wooded areas. During daylight hours, this snake generally hides underground, in or under logs, or under rocks, stumps or other surface cover. Eggs are laid (often communally) underground or under logs or rocks.

Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.

Locally Migrant: Yes. At least some populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: No. No populations of this species make annual migrations of over 200 km.

Distance between hibernaculum and summer range estimated to average 121 m in Kansas study (Fitch 1975).

Ringneck snakes prey upon small Caudata, Squamata, Anura, Oligochaeta, and younger Serpentes of other species. The amount of each of these prey types depends upon availability. Those snakes living in Michigan eat mainly Plethodon cinereus. To stop prey from struggling ringneck snakes use constriction, wrapping themselves around their prey and squeezing to subdue them.

Animal Foods: amphibians; reptiles; mollusks; terrestrial worms

Prey of D. punctatus consists of small salamanders, lizards, and frogs, as well as earthworms and juvenile snakes of other species. Frequency of specific prey in the diet is dependent on availability. reports show that Michigan populations of eastern ringneck snakes (D. punctatus edwardsii) prey almost exclusively on red-backed salamanders. Ringneck snakes employ partial constriction to subdue their prey.

Animal Foods: amphibians; reptiles; mollusks; terrestrial worms

Primary Diet: carnivore (Eats terrestrial vertebrates, Vermivore)

Comments: Eats earthworms; slugs; small salamanders, frogs, lizards, and snakes; and various other small invertebrates.

Ringnecks may play a small role in biodegration by moving through surface debris such as branches and leaves within forests. They also take on the role of predator and prey within their habitat, helping to control pest populations and serving as sustenance for larger animals.

Ecosystem Impact: biodegradation

When ringneck snakes are frightened, they raise their tail into a coil that is presented to the intruder. This is seen in snakes with reddish-orange tails, where the red color can act as a warning signal. When the snake is held, or further provoked, a musky, smelly mucus is secreted from the corners of its mouth.

Predators include Micrurus fulvius, Lampropeltis, and Coluber constrictor. Other snakes may also be predators of ringneck snakes if they share the same habitat. Wild hogs, opossums, shrews, armadillos, skunks, screech owls, and bullfrogs are possible predators. Large spiders and centipedes have been seen eating young ringneck snakes.

Known Predators:

• blue racers (Coluber_constrictor)
• kingsnakes (Lampropeltis)
• wild hogs (Sus_scrofa)
• Virginia opossums (Didelphis_virginiana)
• nine-banded armadillos (Dasypus_novemcinctus)
• striped skunks (Mephitis_mephitis)
• easter screech owls (Otus_asio)
• bullfrogs (Rana_catesbeiana)
• northern coral snakes (Micrurus_fulvius)

Anti-predator Adaptations: aposematic

Ringnecks may play a small role in biodegration by moving through surface debris such as branches and leaves within forests. They also take on the role of predator and prey within their habitat, helping to control pest populations and serving as sustenance for larger animals.

Ecosystem Impact: biodegradation

When ringneck snakes are alarmed, the tail is coiled and raised toward the intruder. This behavior occurs only in populations where the orange-red posterior is present. The red coloration may act as a warning signal. Western subspecies feign death on further provocation. When the snake is held, a musky saliva is secreted from the corners of its mouth, accompanied by a pungent, clinging odor.

Predators include coral snakes, kingsnakes, and racers. Other snakes sharing the geographical areas of the ringneck snake may also be predators. In addition, wild hogs, opossums, shrews, armadillos, skunks, screech owls, and bullfrogs are all suspected predators. Large spiders and centipedes have been observed feeding on juvenile ringneck snakes.

Known Predators:

• blue racers (Coluber constrictor)
• kingsnakes (Lampropeltis)
• wild hogs (Sus scrofa)
• Virginia opossums (Didelphis virginiana)
• nine-banded armadillos (Dasypus novemcinctus)
• striped skunks (Mephitis mephitis)
• easter screech owls (Otus asio)
• bullfrogs (Lithobates catesbeianus)
• northern coral snakes (Micrurus fulvius)

Anti-predator Adaptations: aposematic

Diadophis punctatus is prey of:
Rana catesbeiana
Coluber constrictor
Micruroides euryxanthus
Micrurus fulvius
Otus asio
Didelphis virginiana
Mephitis mephitis
Sus scrofa

This list may not be complete but is based on published studies.

Diadophis punctatus preys on:
Annelida
Mollusca
Amphibia
Reptilia

This list may not be complete but is based on published studies.

Note: For many non-migratory species, occurrences are roughly equivalent to populations.

Estimated Number of Occurrences: > 300

Comments: This species is represented by thousands of occurrences or subpopulations.

>1,000,000 individuals

Comments: Total adult population size is unknown but undoubtedly exceeds 1,000,000. Local subpopulations may include several thousand individuals (e.g., Fitch 1975, 1982).

Population density was estimated to be 719-1849/ha in Kansas study. Distances between recaptures averaged 80 m (range 0-1700 m) in same study; home range had maximum dimension of about 140 m (Fitch 1975).

Touching, rubbing, head nuzzling, and pheromones are all ways of communication for ringneck snakes. Males rub their heads on females during mating, and females release pheromones from their skin when trying to attract a mate. Ringneck snakes perceive the world around them via sight, smell, and touch.

Communication Channels: tactile ; chemical

Other Communication Modes: pheromones

Perception Channels: visual ; tactile ; chemical

Touching, rubbing, head nuzzling, and pheromones are all ways of communication for ringneck snakes. Males rub their heads on females during mating, and females release pheromones from their skin when trying to attract a mate. Ringneck snakes perceive the world around them via sight, smell, and touch.

Communication Channels: tactile ; chemical

Other Communication Modes: pheromones

Perception Channels: visual ; tactile ; chemical

Comments: Inactive in winter in most areas.

After hatching, females start off smaller then males, measuring about 20 cm while males are about 21.9 cm. By the third year they are longer than most males, measuring about 29 cm while males measure about 28 cm.

Female ringneck snakes reach an average of 20 cm in the first year, representing a 60% increase in length. In the second year they grow to about 24.5 cm and, in the third year, females tend to increase to approximately 29 cm. The fourth year they tend to reach about 34 cm, and in the fifth year they can be expected to reach 39 cm.

Males are slightly larger in the earlier stages of development, usually reaching 21.9 cm in the first year, 26 cm in the second, 28 cm in the third year, and about 31 cm in the fourth year.

The longest recorded lifespan in captivity is 6 years 2 months. In the wild, though, ringnecks have been recorded as having lived over 10 years. It is thought that they may have a lifespan approaching 20 years in the wild.

Range lifespan
Status: wild: 20 (high) years.

Average lifespan
Status: wild: 10 years.

Range lifespan
Status: captivity: 6 (high) years.

The longest recorded lifespan in captivity is 6 years 2 months. In the wild, though, ringnecks have been recorded as having lived over 10 years. It is thought that they may have a lifespan approaching 20 years in the wild.

Range lifespan
Status: wild: 20 (high) years.

Average lifespan
Status: wild: 10 years.

Range lifespan
Status: captivity: 6 (high) years.

Female ringneck snakes release pheromones from their skin which help attract potential mates. Actual mating between ringneck snakes has rarely been recorded. While mating, males rub their mouths on their mates and bite their mate's neck.

Mating System: polygynandrous (promiscuous)

Ringneck snakes mate in spring or fall, and eggs are laid in June or early July. Female snakes lay 3 to 10 eggs at one time. They are laid in covered, moist locations. In places where many ringneck snakes live together, it is not uncommon to find eggs from different females laid in the same area. Each egg is white with yellow ends, and it is about 2.5 cm long. Eggs hatch in August or September.

Both male and femlae snakes are sexually mature when they are three years old, or by their fourth summer. Males are smaller than females when they reach this point.

Breeding interval: Ringneck snakes breed once each year.

Breeding season: Ringneck snakes breed in the spring or fall.

Range number of offspring: 3 to 10.

Average age at sexual or reproductive maturity (female): 3 years.

Average age at sexual or reproductive maturity (male): 3 years.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; oviparous ; delayed fertilization

Ringneck snake eggs are not cared for, there is no parental investment after choosing a nest site and laying the eggs. This largely contributes to the high mortality rate of young ringneck snakes.

Parental Investment: no parental involvement

Pheromones released from the skin of a female ringneck snake attracts males during mating season. Rarely have ringneck snakes been observed mating, amounting to no more than 6 recorded sightings. While mating, males rub their closed mouths on their mate's body. They then bite the female around her neck ring, align their bodies with the female's, and release their sperm.

Mating System: polygynandrous (promiscuous)

Mating of ringneck snakes can occur in spring or fall--delayed fertilization is possible--and eggs are laid in June or early July. Females lay eggs each year, 3 to 10 eggs can be laid at one time, and are deposited together in covered, moist locations. In areas where colonies exist, it is not uncommon to find eggs laid in communal nests. A single egg is white with yellow ends and is elongated, approximating 1 inch in length. Juveniles hatch in August or September.

Reproductive maturity of both sexes is reached at the age of three years, that is, by their fourth summer. Male ringneck snakes mature at a smaller size than females do.

Breeding interval: Ringneck snakes breed once each year.

Breeding season: Ringneck snakes breed in the spring or fall.

Range number of offspring: 3 to 10.

Average age at sexual or reproductive maturity (female): 3 years.

Average age at sexual or reproductive maturity (male): 3 years.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; oviparous ; delayed fertilization

Ringneck snake eggs are not cared for, there is no parental investment after choosing a nest site and laying the eggs. This largely contributes to the high mortality rate of young ringneck snakes.

Parental Investment: no parental involvement

Lays clutch of 1-18 eggs, usually in June or July. Eggs hatch in up to about 8 weeks. Sexually mature in 2-3 years. May possibly lay two clutches in south. Eggs are laid from late May through August in Florida. Communal nesting common.

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Specimens with Barcodes: 3
Species With Barcodes: 1

Three subspecies of ringneck snakes may soon be protected under federal endangered species laws. They are San Diego ringneck snakes, San Bernardino ringneck snakes, and key ringneck snakes. Key ringneck snakes are currently considered an endangered species in Florida. Regal ringneck snakes and northwestern ringneck snakes are protected under state law in Idaho.

Although ringneck snakes are rarely observed, they are fairly common throughout their range. They are secretive snakes and generally remain hidden.

IUCN Red List of Threatened Species: least concern

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

Year Assessed

Assessor/s

Reviewer/s

Justification

Three subspecies are candidates for the federal endangered or threatened species lists. They are San Diego ringneck snakes (Diadophis punctatus similis), San Bernardino ringneck snakes (Diadophis punctatus modestus), and key ringneck snakes (Diadophis punctatus acricus). Key ringneck snakes are also a threatened species in the state of Florida and are protected under state law. The range of that subspecies is limited to a single island in the Florida Keys. In Idaho, regal ringneck snakes (Diadophis punctatus regalis), and northwestern ringneck snakes (Diadophis punctatus occidentalis), are considered species of special concern, and are protected under state law.

Although ringneck snakes are rarely observed, they are fairly common throughout their range. They are secretive snakes and generally remain hidden.

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

IUCN Red List of Threatened Species: least concern

Canada

Rounded National Status Rank: N5 - Secure

United States

Rounded National Status Rank: N5 - Secure

Rounded Global Status Rank: G5 - Secure

Intrinsic Vulnerability: Moderately vulnerable

Population

Population Trend

Global Short Term Trend: Relatively stable (=10% change)

Comments: Extent of occurrence, area of occupancy, number of subpopulations, and population size are very large and probably relatively stable.

Global Long Term Trend: Increase of 10-25% to decline of 30%

Degree of Threat: Unknown

Comments: No major threats have been identified. Many local populations have been lost or reduced as a result of habitat destruction (Ernst and Ernst 2003), but these appear to amount to a small minority of the total distribution.

Major Threats

Conservation Actions

Global Protection: Very many (>40) occurrences appropriately protected and managed

Comments: Many occurrences are in national parks or other well-protected areas.

Ringneck snakes do not adversely affect humans, though, at times, they may cause a slight inconvenience. Due to urbanization, it is not uncommon to find ringneck snakes in one's basement. In these circumstances ringnecks pose no real threat, and must simply be relocated.

Negative Impacts: household pest

Ringneck snakes are valued in the pet trade for their attractive coloration, and also play a part in research and education. Because they pose no real threat to humans, they are ideal for work with younger children in a school setting. Ringneck snakes also help in controling pest populations.

Positive Impacts: pet trade ; research and education; controls pest population

Ringneck snakes do not adversely affect humans, though, at times, they may cause a slight inconvenience. Due to urbanization, it is not uncommon to find ringneck snakes in one's basement. In these circumstances ringnecks pose no real threat, and must simply be relocated.

Negative Impacts: household pest

Ringneck snakes are valued in the pet trade for their attractive coloration, and also play a part in research and education. Because they pose no real threat to humans, they are ideal for work with younger children in a school setting. Ringneck snakes also help in controling pest populations.

Positive Impacts: pet trade ; research and education; controls pest population