A first look at whale sharks in Hawaiian waters: Using citizen science to study the world's largest fish, Rhincodon typus

Abstract

1. The world's largest fish, the whale shark (Rhincodon typus), is a circum-tropically distributed and globally endangered species, that is widely studied at predictable aggregation sites. The main Hawaiian Islands are not known to have large aggregations of whale sharks; however, they have been anecdotally reported here with some regularity. To date, little is known about this charismatic species in Hawaiian waters.2. This study is the first effort to examine whale shark demographics and movements in a previously unstudied region of the world. Here, citizen science was used to investigate the abundance, seasonality (if any) and occurrence of

Dots in the dark: dorsal polychromatism in the endemic Xingu Freshwater Stingray

“…Polychromatic forms in cartilaginous fishes, mainly Batoidea, are not a new issue. Several studies use color polymorphism for the photo‐identification of specific individuals and also as a non‐invasive alternative to mark‐recapture studies (Bassos‐Hull et al., 2014; Benjamins et al., 2018; Cerutti‐Pereyra et al., 2018; Couturier et al., 2011; Davies et al., 2012; Dudgeon et al., 2008; González‐Ramos et al., 2017; Marcoux et al., 2023; Marshall et al., 2011; Navarro et al., 2018). In most of these studies, however, it is not clear whether color diversity is related to other factors such as sex, reproductive stage, or size.…”