Insular and mainland interconnectivity in the movements of oceanic manta rays (Mobula birostris) of Mexico in the Eastern Tropical Pacific

November 2024

Robert D. Rubin, Katherine R. Kumli, A. Peter Klimley, Joshua D. Stewart, James T. Ketchum, Edgar M. Hoyos‑Padilla, Felipe Galván‑Magaña, Aldo A. Zavala‑Jiménez, Iliana A. Fonseca‑Ponce, Megan Saunders, P. Santiago Dominguez‑Sanchez, Paul Ahuja, Corey R. Nevels, Paúl Antonio Preciado González, Antonio Corgos, Sara J. Diemer

Keywords: Residency • Migration • Photo identifcation • Telemetry • Tropical Eastern Pacific

Summary: The oceanic manta ray (Mobula birostris) is the largest species of ray, and is found in tropical and subtropical seas around offshore islands and seamounts with high productivity. This study tracked 22 manta rays from the Revillagigedo Archipelago and Bahia de Banderas, revealing their movements between the Revillagigedo Archipelago, Bahia de Banderas, Bahia de Navidad, and the Gulf of California over 21 years. Manta rays travelled between the Revillagigedo Archipelago and the mainland, with some journeys lasting up to 15.3 years. Findings suggest these populations form a connected metapopulation. The research highlights new telemetry and long-term field data for these regions.

Abstract

“The oceanic manta ray (Mobula birostris) is the largest batoid. The species is distributed circumglobally in tropical and subtropical seas around ofshore islands and seamounts where upwelled waters are present with high productivity. They inhabit the waters of the Eastern Tropical Pacifc, with known aggregations around the Revillagigedo Archipelago (RA), and in Bahia de Banderas (BB), along the western edge of the Mexican mainland. Manta rays from the Archipelago and Bahia de Banderas were identifed by their unique color markings, in photographs collected by citizen scientists and researchers, and/or coded acoustic beacons detected by autonomous monitors deployed at sites mentioned below. Here we report the movements of 22 individuals that moved between RA and several aggregation sites over 21 years: BB, Bahía de Navidad (BN), and the Gulf of California (GC). Two manta rays moved from Isla Cerralvo in the southern GC to RA over periods of 3.0 and 3.3 years (y). Seventeen mantas moved back and forth between RA and the mainland over periods ranging from 0.1 to 15.3 years. The longest manta transit was from RA to Bahía de Navidad on the western coast of Mexico, traversing approximately 560 km. Findings suggest that the three populations constitute a metapopulation, with connectivity between the three locations. Resulting from the scarcity of past biological research conducted in RA and GC, we introduce some information from telemetry monitoring and signifcant observational data from the author’s long-term feld research.”

Author Affiliations

  • Department of Biology, Santa Rosa College

  • Pacific Manta Research Group, University of California

  • The Manta Trust

  • Department of Wildlife, Fish, and Conservation Biology, University of California

  • Biotelemetry Consultants

  • Department of Fisheries, Wildlife, and Conservation Sciences, Hatfeld Marine Science Center, Oregon State University

  • Pelagios-Kakunjá Cuauhtémoc 155, Col. El Manglito

  • Fins Attached: Marine Research and Conservation

  • Centro Interdisciplinario de Ciencias Marinas (CICIMAR-IPN), Instituto Politécnico Nacional