The Cuban Tree Frog, Osteopilus septentrionalis, is a large arboreal amphibian native to Cuba, the Cayman Islands, and the Bahamas. Females often grow to nearly twice the size of males, making it one of the largest tree frogs in North America. Its success in new environments, such as Florida, is closely linked to its remarkably broad and opportunistic diet. This predatory nature influences its ecological role both in its native range and in regions where it has been introduced.
Natural Diet and Hunting Strategies
The Cuban Tree Frog is a generalist feeder, including almost any moving creature it can subdue. While invertebrates form the majority of its consumed biomass, the frog actively hunts a vast array of insects, including beetles, roaches, moths, and crickets, alongside spiders and snails. This adaptability allows it to thrive in diverse habitats, from natural forests to urbanized areas that provide a surplus of insect life.
The species is an ambush predator, employing a sit-and-wait strategy, often remaining stationary on vertical surfaces like tree trunks or walls. Hunting is primarily nocturnal, coinciding with the activity of many prey items, such as moths and night-active insects. The frog’s highly flexible and disproportionately large mouth facilitates the consumption of unusually large food items. This capacity allows them to feed on prey that is often a significant fraction of their own body size.
The diet extends beyond invertebrates to include small vertebrates, which is uncommon among tree frogs. Documented vertebrate prey includes small lizards, such as brown anoles, and tiny snakes like the Florida brown snake. The Cuban Tree Frog is also a known predator of other frogs, consuming species like the southern leopard frog and various native tree frogs. Tadpoles of this species exhibit omnivorous habits and are known to engage in cannibalism.
Ecological Impact of Their Appetite
The Cuban Tree Frog’s diet contributes to its success in colonizing new ecosystems. In areas where it has been introduced, such as the southeastern United States, its predatory habits directly disrupt local food webs. The ability to consume a wide range of food items, from insects to large vertebrates, gives it a distinct competitive advantage over specialized native amphibians.
This allows the Cuban Tree Frog to occupy the same ecological niche as native species while simultaneously preying upon them. Their large gape allows adult Cuban Tree Frogs to capture and swallow native tree frogs, which are often smaller. This predation pressure has been observed to cause declines in local populations of native tree frogs, such as the squirrel treefrog and the green treefrog, particularly in urban and suburban settings. Furthermore, their tadpoles are superior competitors against native frog tadpoles, inhibiting the growth and development of species like the southern toad and green treefrog larvae.
Feeding Cuban Tree Frogs in Captivity
For those who keep the Cuban Tree Frog as a pet, providing a diet that mimics its natural carnivorous tendencies is necessary for good health. The captive diet should consist primarily of live, moving insects, such as gut-loaded crickets, roaches, earthworms, and silkworms. Gut-loading ensures the nutrients are passed along by feeding the prey items a nutritious diet just before offering them to the frog.
Feeding frequency depends heavily on the frog’s age and size. Juveniles, which are rapidly growing, require daily feeding, typically consuming two to four appropriately sized insects per meal. Adult frogs should be fed less often, generally two to three times per week, with a meal consisting of two to five food items. It is important to ensure the prey item is no wider than the space between the frog’s eyes to prevent choking.
A proper diet requires supplementation to prevent nutritional deficiencies, especially metabolic bone disease. Prey items must be dusted with a high-quality calcium powder at nearly every feeding for juveniles and two to four times per week for adults. A separate multivitamin supplement, ideally one containing Vitamin D3, should also be provided once per week to ensure a balanced intake of micronutrients. A large, shallow water dish containing clean, de-chlorinated water should always be available, as the frogs will often soak to absorb water through their skin.