The number of individual whale shark Rhincodon typus sightings registered October 2015-March 2018 in Bahia de La Paz, Mexico, ranged from 73 to 129 animals per season (total 1662), with the majority of them identified as males. Density plot maps showed high correlations in sightings between sample seasons and revealed potential hotspot areas. Our study provides an essential baseline of information for the management of whale shark conservation and the associated touristic activities in the region.

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We report the presence of striped marlin larvae in coastal waters of the mouth of the Gulf of California, collected during seven oceanographic cruises during 1990 to 1993. From 169 sampled stations, 30 produced a total of 68 larvae of 2.4–30.5 mm total length. Most of the larvae were about 3 mm, indicating a recent spawn. The sea surface temperature at the sampled stations ranged from 19.4°C to 32.0°C, but larvae were caught at stations with temperatures between 27.8°C and 31.5°C. These results clarify the existence of a spawning area of striped marlin in the eastern Pacific, located closer to the coast than previously believed, during several months of the year.

In this study we present the first attempt at modelling the feeding behaviour of whale sharks using a machine learning analytical method. A total of eight sharks were monitored with tri-axial accelerometers and their foraging behaviours were visually observed. Our results highlight that the random forest model is a valid and robust approach to predict the feeding behaviour of the whale shark. In conclusion this novel approach exposes the practicality of this method to serve as a conservation tool and the capability it offers in monitoring potential disturbances of the species.

Primer registro del dinoflagelado Prorocentrum panamense (Prorocentrales, Dinophyceae) en el Pacífico Mexicano recolectado en el Archipiélago de RevillagigedoSe reporta por primera vez el dinoflagelado Prorocentrum panamense en la costa del Pacífico de México. Diez células de P. panamense se encontraron en muestras de red procedentes de aguas superficiales en tres islas del Archipiélago de Revillagigedo donde se recolectaron muestras en marzo de 2017. Los sitios de muestreo tenían una profundidad aproximada de 60-70 m y la temperatura superficial del agua estaba entre 21 y 23 ºC.