Changing Planet

The Gladiator Tree Frog

This post is the latest in the series Places, Experiences and Objects to Dream About, which profiles marvelous locations, unique life experiences and objects of interest to modern explorers that Kike discovers during my travels.

Ranked as one of the 12 most beautiful national parks in the world by Forbes, Manuel Antonio National Park is dotted with breathtaking white sand beaches and lush  hiking trails. A true small gem, the park is the smallest of Costa Rica. Yet it does have some unique features like several coves surrounded by the backdrop of mountains and stretches of tropical jungle.




Given its high biodiversity, hiking around the park is an explorer’s dream. There at least 109 species of mammals and 184 species of birds. But what caught my eye this time around was a tiny tree frog. The gladiator frog, Hypsiboas rosenbergialso known as Rosenberg’s gladiator tree frog, measures about 3.3 inches and is known for the aggressiveness displayed by males. Female gladiator frogs mate only with males capable of providing a nest, which puts pressure on males to either build one or conquer one from other males. This is when the gladiator-like fights kick in. Male gladiators remain very vigilant of intruding males until the eggs hatch. If a male poses a threat to the nest, they can engage in fierce wrestling matches, often times resulting in death or serious permanent damage to one of the contenders. The primary weapons used by males are their large dagger-like spines, which are skillfully used, earning them the gladiator title.

Kike shares his expertise and experiences as a National Geographic Expert on several Costa Rica/Panama Lindblad Expeditions.


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Award-winning photographer, journalist, and author Kike Calvo (pronounced key-keh) specializes in culture and environment. He has been on assignment in more than 90 countries, working on stories ranging from belugas in the Arctic to traditional Hmong costumes in Laos. Kike is pioneering in using small unmanned aerial systems to produce aerial photography as art, and as a tool for research and conservation. He is also known for his iconic photographic project, World of Dances, on the intersection of dance, nature, and architecture. His work has been published in National Geographic, New York Times, Time, The Wall Street Journal, The Washington Post, New York Magazine, Rolling Stone, and Vanity Fair, among others. Kike teaches photography workshops and has been a guest lecturer at leading institutions like the School of Visual Arts and Yale University. He is a regular contributor to National Geographic blog Voices. He has authored nine books, including Drones for Conservation; So You Want to Create Maps Using Drones?; Staten Island: A Visual Journey to the Lighthouse at the End of the World; and Habitats, with forewords by David Doubilet and Jean-Michel Cousteau. Kike’s images have been exhibited around the world, and are represented by the National Geographic Image Collection. Kike was born in Spain and is based in New York. When he is not on assignment, he is making gazpacho following his grandmother’s Andalusian recipe. You can now buy Kike´s products: You can travel to Colombia with Kike:

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