Cuban Tree Frog (Osteopilus septentrionalis)
Order: Anura; Family: Hylidae (Tree Frogs); Genus: Osteopilus; Species: O. septentrionalis. This genus is characterized by large, robust forms with some species having skin fused to the skull (co-ossification).
Species
Cuban Tree Frog (Osteopilus septentrionalis)
Family
Order: Anura; Family: Hylidae (Tree Frogs); Genus: Osteopilus; Species: O. septentrionalis. This genus is characterized by large, robust forms with some species having skin fused to the skull (co-ossification).
Size
This is the largest tree frog in North America. SVL ranges from 1.5 to over 5 inches (3.8 to 12.7 cm). Females are significantly larger than males. Weights vary but they are noticeably 'heavier' than native hylids.
Conservation
Status: Least Concern (Invasive). In regions like Florida, they are considered a major threat to biodiversity because they outcompete and consume native frog species.
Description
An imposing and hardy amphibian, the Cuban Tree Frog is a master of suburban survival. Often found clinging to windows or hiding in garden pots, its warty skin and oversized gold eyes give it a prehistoric appearance. While fascinating for its size and adaptability, its presence outside its native range is a sign of ecological imbalance.
Key Features
Oversized toe pads, warty skin, very large size (up to 5 inches), and skin on the head fused to the skull.
Physical Description
A very large, robust tree frog with a broad head. The eyes are prominent with horizontal pupils and golden-yellow irises. It features exceptionally large toe pads for climbing and a visible, large tympanum (eardrum). The limbs are powerful, and the snout is blunt.
Skin Texture & Coloration
The skin is highly variable and can change based on temperature and surroundings. It ranges from olive-green and bronze to gray or almost white, often with irregular dark blotches or mottling. The texture is notoriously warty or granular, distinguishing it from many smoother native tree frogs. In juveniles, blue-ish bones may be visible through the skin of the legs.
Distinguishing Features
The most diagnostic feature is the skin on the top of the head being fused to the skull (in adults, if you gently move the skin on the head, it won't budge). Other markers include excessively large toe pads (wider than the toe) and the warty skin. They lack the distinct white stripe seen in Green Tree Frogs.
Habitat
Highly adaptable; found in tropical forests, hardwood hammocks, and mangroves, but thrives in suburban areas. It is frequently found on houses, near outdoor lights, in potted plants, and in cisterns or PVC pipes.
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, with tropical/subtropical climates being preferred.
Behavior
Primarily nocturnal and highly predatory. They are known for 'sit-and-wait' hunting near light sources that attract insects. They can be aggressive toward other frogs and will seek shelter in crevices or pipes during the day to avoid desiccation.
Diet & Feeding
Generalist carnivores. They eat insects, spiders, and other invertebrates, but notably prey upon smaller native frogs, lizards, and even small snakes or birds if they can fit them in their mouths.
Reproduction
Explosive breeders, typically triggered by heavy summer rains. They use any standing water, including pools, buckets, and birdbaths. Amplexus is axillary. Females can lay thousands of eggs in a single clutch throughout the breeding season.
Vocalizations
The call is a raspy, variable 'snoring' or 'grating' sound, often compared to a door creaking or a rhythmic 'scritch-scritch'. It is less melodic than native hylids and can be quite loud in chorus.
Life Cycle
Eggs hatch into dark-colored tadpoles within 24-48 hours. The larval stage lasts 3 to 8 weeks depending on temperature and food availability. Metamorphs are about 0.5 inches long and reach sexual maturity within a year.
Conservation Status
Status: Least Concern (Invasive). In regions like Florida, they are considered a major threat to biodiversity because they outcompete and consume native frog species.
Toxicity & Defense
Their skin produces a noxious mucus that can irritate human eyes and mucus membranes. They don't have lethal toxins like dart frogs but can cause a burning sensation or allergic reaction. Some predators, like certain snakes and birds, are resistant or avoid the skin.
Ecological Role
In its invasive range, it acts as an apex predator among amphibians, drastically reducing populations of native Green and Squirrel Tree Frogs through predation and competition for resources.
Similar Species
Gray Tree Frog (Dryophytes versicolor) - smaller with brighter yellow/orange inner thighs; Green Tree Frog (Dryophytes cinereus) - smoother skin and distinct lateral white stripe.
Observation Tips
Look around outdoor light fixtures on warm, humid nights. Check inside the mouths of PVC pipes or under the large leaves of tropical plants during the day.
Handling & Safety
If handling is necessary, use gloves or a plastic bag. The mucus can cause intense irritation if it gets in your eyes or mouth. Always wash hands thoroughly after contact. In areas where they are invasive, local wildlife agencies often recommend humane euthanasia.
Seasonal Activity
Most active during the wet summer months (May–October in Florida). They may become inactive or hide deep in crevices during dry cold snaps, but they do not hibernate in the traditional sense.
Cultural Significance
In its native Cuba, it is a common part of the night soundscape. In Florida, it has become a 'villain' of local ecology, featured in education campaigns urging residents to humanely remove them to protect native wildlife.
Interesting Facts
They are known 'hitchhikers,' spreading across the US by hiding in ornamental plants shipped from Florida. They are also known to cause power outages by shorting out utility switches in electrical boxes.