Cuban Tree Frog (Osteopilus septentrionalis)
Order: Anura; Family: Hylidae; Genus: Osteopilus; Species: O. septentrionalis. Members of this genus are characterized by their large size and 'bony' skull (osteopilus means 'bony cap').
Species
Cuban Tree Frog (Osteopilus septentrionalis)
Family
Order: Anura; Family: Hylidae; Genus: Osteopilus; Species: O. septentrionalis. Members of this genus are characterized by their large size and 'bony' skull (osteopilus means 'bony cap').
Size
One of the largest tree frogs in North America. Females are significantly larger, reaching 3-5.5 inches (76-140mm) SVL; males are smaller, usually 2-3 inches. Juveniles at metamorphosis are roughly 0.5 inches.
Conservation
IUCN: Least Concern. In their invasive range (like Florida), they are considered an ecological pest and a significant threat to native biodiversity. Populations are increasing and expanding.
Description
The Cuban Tree Frog is a formidable and adaptable amphibian. In the night garden, it appears as a mottled, warty sentinel perched on window screens or walls. Its large golden-bronze eyes and oversized toe pads give it a distinct, almost alien appearance as it waits to ambush prey attracted to artificial lights.
Key Features
Large size (>2 inches as adult), exceptionally large 'suction-cup' toe pads, and warty skin. If the skin on the head feels fused to the bone, it is a definitive ID.
Physical Description
A robust, large tree frog with a broad head. It features prominent bulbous eyes with horizontal pupils and very large, circular toe pads relative to its body. The hind legs are long and powerful, designed for leaping. A key feature is the skin on the head which is often fused to the skull in older adults.
Skin Texture & Coloration
Skin texture is highly variable, ranging from nearly smooth to distinctly warty/tuberculate. Coloration is polymorphic, appearing in shades of gray, tan, bronze, or olive green. They often exhibit a mottled or 'lichen-like' pattern and can change brightness based on temperature and surroundings. The hidden surfaces of the thighs often show a yellow or orange wash.
Distinguishing Features
The most diagnostic feature is the size of the toe pads (wider than the toe) and the warty skin. Unlike many native tree frogs, this species has a 'bony' head where the skin is co-ossified with the skull. They also lack the distinct stripes found in North American green tree frogs.
Habitat
Highly adaptable. Occupies urban and suburban areas (porches, pipes, potted plants), forests, swamps, and hammocks. They are primarily arboreal but are frequently found near human dwellings where artificial lights attract insect prey.
Geographic Range
Native to Cuba, the Bahamas, and the Cayman Islands. It is a highly successful invasive species in Florida, Georgia, and various Caribbean islands. They have also been reported as hitchhikers in potted plants across many US states and even Hawaii.
Behavior
Nocturnal and highly predatory. They are known for 'sit-and-wait' hunting near light sources. They are aggressive and often displace or consume native tree frog species. If threatened, they may secrete a noxious mucus or jump long distances.
Diet & Feeding
Extreme generalists. They consume beetles, roaches, spiders, and larger prey including smaller frogs (especially native Hyla species), small lizards, and occasionally hatchling birds or snakes.
Reproduction
Explosive breeders triggered by heavy rain. They utilize any standing water, including ponds, birdbaths, and swimming pools. Amplexus is axillary. A single female can lay over 3,000 eggs in a season, which hatch into black/dark brown tadpoles uniquely adapted to survive in stagnant water.
Vocalizations
The call is a raspy, variably pitched 'snarl' or 'squawk' resembling a notched stick being rubbed. It is often described as a 'muffled bark.' It lacks the musical quality of many native hylids.
Life Cycle
Rapid development. Eggs hatch in 24-48 hours. The tadpole stage lasts 3 to 10 weeks depending on temperature and food. Maturity can be reached within one year, with a total lifespan of 5-10 years in the wild.
Conservation Status
IUCN: Least Concern. In their invasive range (like Florida), they are considered an ecological pest and a significant threat to native biodiversity. Populations are increasing and expanding.
Toxicity & Defense
The skin produces a thick, sticky mucus containing toxins that irritate the mucous membranes of predators (and humans). It can cause intense stinging in the eyes or respiratory irritation if handled then touching the face.
Ecological Role
Invasive apex predator among amphibians. They significantly reduce populations of native frogs through both competition for resources and direct predation. They also serve as prey for owls, snakes, and crows.
Similar Species
Gray Tree Frog (Dryophytes versicolor) - smaller, have a light spot under the eye and bright orange inner hocks. Green Tree Frog (Dryophytes cinereus) - smooth skin, clear lateral white stripe.
Observation Tips
Look on the glass of windows or near outdoor light fixtures at night. During the day, they hide in the 'axils' of palm fronds, bromeliads, or inside pvc pipes and downspouts.
Handling & Safety
Handling should be minimized. If necessary, wear gloves or wash hands immediately after. Do not touch eyes or mouth after handling as the skin secretions are irritating. In invasive regions, local wildlife agencies often recommend humane euthanasia.
Seasonal Activity
Active year-round in tropical climates. In temperate invasive ranges, they are active from late spring through autumn, retreating into deep crevices or building interiors during cold snaps.
Cultural Significance
Mostly regarded as a nuisance species in North America due to their impact on native wildlife and noise. In their native range, they are part of the complex tropical food web.
Interesting Facts
In Florida, they frequently cause short-circuits in electrical transformers and air conditioners by crawling into warm, tight spaces. They are known to cannibalize their own kind if other food is scarce.