Vivid orange shark caught by anglers in Costa Rica in first-of-its-kind sighting
Anglers on a sport fishing trip off Costa Rica reeled in their lines and were stunned when a bright orange shark surfaced near the boat. The 6-foot-long predator turned out to be a first-of-its-kind catch.
Garvin Watson and Juan Pablo Solano set out on a sport fishing trip with the Parismina Domus Dei tour company in August 2024 to fish near Tortuguero National Park, according to a study published Aug. 1 in the peer-reviewed journal Marine Biodiversity.
During the trip, the anglers caught and released a 6-foot-long nurse shark with “intense yellow-orange” coloring, the study said.
Photos shared on Facebook by Parismina Domus Dei show the odd-colored shark, which clearly stands out against the blue-green water. Normally, nurse sharks are uniformly gray.
Seen up close, the shark had “white eyes, with no visible iris” instead of “the typically black iris,” the study said.
Researchers later reviewed the photos, spoke with the fishermen and identified the animal as an adult nurse shark with a “rare” condition known as albino-xanthochromism and a first-of-its-kind record.
Xanthism and albinism are two types of “abnormal pigmentation” caused by genetic mutation and rarely seen in wild sharks, the study said. Albinism reduces the amount of melanin or pigmentation in an animal’s skin and eyes, while xanthism results in “partial or predominantly yellow pigmentation.”
The orange nurse shark was “the first scientifically documented case of total xanthism in the species and the first record from the Caribbean Sea,” researchers said.
Based on the size of the shark, researchers concluded that “this unusual pigmentation did not affect its survival.”
Still, “the discovery of a xanthic G. cirratum (nurse shark) — a rare occurrence among elasmobranchs — raises important questions about the genetic variability and adaptability of nurse sharks,” the study said. “Is this an isolated case? Could it represent an emerging genetic trend within the regional population?”
Researchers suggested “further investigation into how local environmental conditions influence the expression of such genetic traits.”
The research team included Marioxis Macías-Cuyare, Gilberto Rafael Borges Guzmán and Daniel Arauz-Naranjo.
This story was originally published August 14, 2025 at 1:19 PM with the headline "Vivid orange shark caught by anglers in Costa Rica in first-of-its-kind sighting."
