Diving and Foraging Behaviors

Abstract

ManateesManatee and dugongsDugong (Dugong dugon) live in tropical and semi-tropical regions around the world. Their preferred habitatsHabitats, are seagrass beds, rivers, lakesLake, and estuaries. ManateesManatee live in both freshwater and marine systems although habitatHabitats, preferences vary across the three species, while the dugongDugong (Dugong dugon) is entirely marine. Sirenians are shallow water divers, and their diveDives/diving durations are short compared to most other marine mammals. The maximum recorded manateeManatee diveDives/diving duration is 24 min, with the maximum recorded duration of a dugongDugong (Dugong dugon) diveDives/diving being about half that. Even though the durations of dugongDugong (Dugong dugon) divesDives/diving are shorter than those of manateesManatee, current data indicate that dugongsDugong (Dugong dugon) diveDives/diving deeper than manateesManatee. Dive depthsDives/diving depth for manateesManatee generally do not exceed 5 m, other than during occasional travel over deeper water; however, this may be an artifact of water depthDives/diving depth in areas where divingDives/diving data were recorded, or where manateesManatee live. In some parts of their range, dugongsDugong (Dugong dugon) are found over deep-water seagrassSeagrass deep-water beds and divesDives/diving have been recorded to more than 30 m. All extant sirenians eat diverse plant-based dietsDiet: collectively they have been documented feedingFeeding on at least 55 genera of marine and freshwater plants. Although not confirmed for the Amazonian manateeAmazonian Manatee (Trichechus inunguis), it is likely that all extant sirenians eat animal, as well as plant, matter. West Indian and African manateesAfrican manatee (Trichechus senegalensis) have been documented eating marine and freshwater fishFish and invertebratesInvertebrates , and for African manateesAfrican manatee (Trichechus senegalensis), these foodFood resources are a regular part of their dietDiet, arguably making them omnivoresOmnivore . DugongsDugong (Dugong dugon) have been recorded targeting invertebratesInvertebrates at the high latitude limits of their range in winter. All manateesManatee like to drink fresh water, in contrast to dugongsDugong (Dugong dugon), which live entirely in marine systems and apparently meet the water requirements from their foodFood.