“Dule” is a close spelling variant of “dole,” sharing the same likely root in an old word for grief, and the two terms are largely interchangeable in older collective-noun lists. Rather than repeat the same explanation, it’s worth pointing to a turtle phenomenon that makes any group term feel like an understatement: the arribada.
Certain sea turtle species, most famously the olive ridley, gather by the thousands, sometimes tens of thousands, to nest on the same beach within just a few days of each other, an event so massive it has its own Spanish name, meaning “arrival.” Scientists still don’t fully understand what synchronizes these mass nestings, though lunar cycles, wind, and ocean currents are all thought to play a role. It’s one of the largest reptile gatherings on Earth, dwarfing anything the word “dule” was originally coined to describe.
Most turtle gatherings are far more modest than an arribada, but the extreme case is a good reminder of how much size and behavior can vary across turtle species.
Example: “Researchers camped out to document what locals still call a dule of turtles arriving each spring.”
Related: Collective Nouns for Reptiles · What Is a Group of Turtles Called?