Cuban Tree Frog (Osteopilus septentrionalis)
Order: Anura, Family: Hylidae (Treefrogs), Genus: Osteopilus. This species is the largest treefrog in North America, known for its robust build and invasive tendencies.
Species
Cuban Tree Frog (Osteopilus septentrionalis)
Family
Order: Anura, Family: Hylidae (Treefrogs), Genus: Osteopilus. This species is the largest treefrog in North America, known for its robust build and invasive tendencies.
Size
Adults typically range from 2.5 to 5.5 inches (6.4–14 cm). Females are significantly larger than males. This is much larger than any native treefrog species in the United States.
Conservation
IUCN: Least Concern. However, as an invasive species, they are a major conservation threat to native biodiversity, particularly native Green and Squirrel Treefrogs.
Description
The Cuban Tree Frog is a formidable and highly adaptable colossus of the treefrog world. Standing out for its immense size and 'bully' behavior, it is a common sight in Florida suburbs, often peering through windows at night. Its warty skin and oversized toe pads give it a prehistoric appearance as it dominates backyard ecosystems.
Key Features
Enormous toe pads, warty skin, fusion of skin to skull, and large adult size (over 2.5 inches).
Physical Description
A large, robust treefrog with a dorsoventrally flattened body. Its most distinctive features include very large toe pads for climbing and eyes that are large and prominent. The head is broad, and in adults, the skin on top of the head is often 'co-ossified' (fused) to the skull.
Skin Texture & Coloration
The skin is highly variable, ranging from warty to relatively smooth. Coloration fluctuates based on temperature and light, appearing gray, tan, brown, or olive green. They often have splotchy or mottled patterns and lack the distinctive dark 'X' mark found on similar species.
Distinguishing Features
Large, expanded toe pads; warty skin; and the unique fusion of skin to the skull (can be felt as a hard plate). It lacks the dorsolateral ridges of true frogs and the markings of the Gray Treefrog. Large size is a key indicator for adults.
Habitat
Highly adaptable. Occupies urban environments, gardens, and wetlands. They are frequently found on human structures like walls, windows, and patio umbrellas (as seen in the photo), seeking moisture and warmth.
Geographic Range
Native to Cuba, the Bahamas, and the Cayman Islands. Highly invasive in Florida and spreading throughout the Southeastern United States and the Caribbean due to human transport.
Behavior
Nocturnal and highly predatory. They are known to congregate around porch lights to catch insects and will actively hunt and eat smaller native frogs, lizards, and even small birds.
Diet & Feeding
Generalist carnivore. Their diet includes beetles, roaches, spiders, and a significant amount of other amphibians. They are sit-and-wait predators but can be quite aggressive in their pursuit of prey.
Reproduction
Explosive breeders, typically triggered by heavy summer rains. They use any available standing water, including pools and buckets. Males have a loud, raspy call. Eggs are laid in a film on the water surface.
Vocalizations
The call is a low-pitched, raspy, or grating 'snore' or 'croak,' similar to the sound of a squeaky door. It is distinct from the musical trills of native Hyla species.
Life Cycle
Standard metamorphic cycle. Eggs hatch within 48 hours. Tadpoles are dark and can develop rapidly (3–4 weeks) in warm conditions. They reach sexual maturity within a year.
Conservation Status
IUCN: Least Concern. However, as an invasive species, they are a major conservation threat to native biodiversity, particularly native Green and Squirrel Treefrogs.
Toxicity & Defense
The skin produces a thick, irritating mucus. This secretion can cause burning in the eyes, sneezing, and respiratory irritation in humans, and is foul-tasting to many predators.
Ecological Role
In its invasive range, it acts as a significant threat to native populations through both competition for resources and direct predation (as an apex predator in the microhabitat).
Similar Species
Gray Treefrog (Hyla versicolor): Smaller, has a dark 'X' on back. Squirrel Treefrog (Hyla squirella): Much smaller, smooth skin. Green Treefrog (Hyla cinerea): Slender, green, with a side stripe.
Observation Tips
Check outdoor lights at night, or look inside PVC pipes, gutters, and large-leaved plants like bromeliads during the day where they hide to stay moist.
Handling & Safety
Handle with gloves or a plastic bag. Their skin secretions are highly irritating to human mucous membranes. Always wash hands thoroughly after contact.
Seasonal Activity
Active year-round in tropical climates. In more temperate areas, they are most active during the warm, wet months of summer and become dormant or seek deep shelter during cold snaps.
Cultural Significance
In its invasive range, it is primarily viewed as a pest. In Florida, residents are often encouraged to 'humanely euthanize' them to protect native wildlife populations.
Interesting Facts
They are known as 'transformers' because of their extreme color-changing abilities. They are also notorious for causing power outages by shorting out electrical breakers in air conditioners.