In the Gulf of Mexico, the bulk of published studies for sea turtles have focused on northern (United States) waters where economic resources are centered, with fewer studies in the southern portion of the basin, resulting in significant knowledge gaps in these underrepresented areas. Similarly, publications on adult sea turtles are dominated by research on females that come ashore to nest and can be readily studied (e.g., through the collection of biological samples and the application of satellite-telemetry devices), whereas information on adult male sea turtles is scarce. The goal of this paper is to begin filling these knowledge gaps by synthesizing available data on adult male sea turtles in the southern Gulf of Mexico. We used satellite-telemetry, boat- and drone-based surveys, and stranding records combined with ocean circulation modeling to better understand the spatial distribution of male loggerhead (Caretta caretta), green (Chelonia mydas), hawksbill (Eretmochelys imbricata), and Kemp’s ridley (Lepidochelys kempii) sea turtles in the southern Gulf of Mexico. These spatially explicit analyses will provide context for opportunistically collected data on male sea turtles and better contribute to the management and restoration of sea turtle populations that use the Gulf of Mexico. Moreover, this synthesis can serve as a launching point for directed studies on male sea turtles in this region.

Sea turtles are migratory species that occupy several marine and coastal habitats along their different life stages. The study of the spatial and temporal distribution of these vertebrates has been revolutionized with technological advances such as satellite telemetry, which in the last two decades has substantially increased its implementation. This technology attends the need of knowing and locating their critical habitats (such as inter-nesting, migrating, feeding and mating) as well as know their migratory movements for the understanding of their biology and protection through the deployment of satellite transmitters on sea turtle individuals. Because the cost of a satellite transmitter is high, its effective deployment on a sea turtle in a quickly, safely, and firmly way is of vital interest to the researcher to ensure that the transmitter persists for an extended time maximizing the information contribution and benefit the research. In this context, the objective of this contribution is to describe and document experiences applying standardized and verified methodological steps for deploying satellite transmitters on hard shell marine turtles. This contribution represents a documented and step-by-step viable description on the path to have clear and versatile basis as reference for the satellite transmitter deployments.

Antecedentes y Objetivos: La restauración ecológica se ha centrado en los componentes físicos y vegetales de los ecosistemas, y ha dejado de lado a la fauna silvestre y sus interacciones. Chelonia mydas es un macroherbívoro en peligro de extinción que anida en playas de México y Cuba, e influye en la vegetación costera con aportaciones de materia orgánica. Los objetivos de este estudio fueron analizar su recuperación poblacional, un índice del verdor de la vegetación de duna, así como la cantidad de materia orgánica estimada de sus nidadas antes y después de la implementación de una Norma Oficial Mexicana. Métodos: Se analizaron datos de entre dos y tres décadas de monitoreo biológico en 16 playas de anidación de Chelonia mydas; a partir de ellos se realizaron tres niveles de análisis de indicadores demográficos, la aportación de materia orgánica de las tortugas en la playa y el vigor vegetal a partir de sensores remotos, además de aplicar los estadísticos pertinentes. Resultados clave: Hubo un crecimiento exponencial del número de anidaciones de tortuga verde (entre 12 y 14% anual), asociado con pulsos de reclutamiento poblacional en los años 2000 y 2008. El aporte de materia orgánica a la playa fue significativamente mayor después de un cambio en la estrategia para manejo de las nidadas en México, y se detectó un incremento en el verdor de la vegetación de duna en zonas de anidación alta de Chelonia mydas. Conclusiones: El incremento de las poblaciones de tortuga verde lleva a reflexionar acerca de las implicaciones que tiene la recuperación de especies de fauna sobre otras comunidades en los ecosistemas que habitan, lo que demanda el análisis de los paradigmas actuales y la adaptación de estrategias que atiendan sus necesidades de manejo, procurando las condiciones de integridad ecológica de sus hábitats.

Marine turtles are of the highest ecological concern in terms of conservation and restoration programs and marine territorial ordering. Marine resource-extracting industries have severe negative impacts on their populations and their habitats. Thus, private industries and decision makers require the best and most robust spatially explicit scientific knowledge for a sustainable and responsible operation and government administration. Therefore, the identification of marine turtle hotspots is a strategic milestone for ecosystem management and an integral ecological knowledge about any region. We identified and delimited marine turtle hotspots in the Gulf of Mexico and Mesoamerican Reef. We analyzed satellite-tracked data of 178 individuals belonging to four marine turtle species. We used Brownian bridge movement models to estimate space use surfaces and map algebra to weight and merge layers of multiple species, life stages, and movement phases. The Yucatan Peninsula and central Veracruz in Mexico, along with the Florida Keys and Louisiana coast in the US, harbor the primary hotspots where marine turtles aggregate. We defined four primary hotspots used for migration in the western Gulf of Mexico, around the Yucatan Peninsula, a northern route following the Loop Current, and a southern one towards Gorda Bank, Central America. This study is the largest assessment of marine turtle hotspots in Mexico and Cuba and supports strategies for reinforcing regional management actions for their conservation, as well as a stronger response and preparedness for tackling anthropic threats to these species. This milestone contributes to extending the knowledge frontiers about these species to a new level.