We didn't think this was a garter in the field but I'm not sure what else it could be. Round pupils, red tongue. No stripes and belly was dark pink. Alternating checker pattern. Very comfortable in the water and seemed to prefer it over land. 2-3ft long.
This oriole has paired up with a male, and they have been carrying on a conversation of sorts over a period of days about whether they are going to build a nest in the leaves of a banana plant.
Male observation here: https://www.inaturalist.org/observations/227956802