They are mainly herbivores, spending most of their time grazing in shallow waters at depths of 1-2 metres (3–7 ft).= = = Natural history = = =
ð eɪ WORD_BOUNDARY ɑ ɹ WORD_BOUNDARY m eɪ n l i WORD_BOUNDARY h ɜː b ɪ v ɔ ɹ z WORD_BOUNDARY s p ɛ n d ɪ ŋ WORD_BOUNDARY m oʊ s t WORD_BOUNDARY ə v WORD_BOUNDARY ð ɛ ɹ WORD_BOUNDARY t aɪ m WORD_BOUNDARY ɡ ɹ eɪ z ɪ ŋ WORD_BOUNDARY ɪ n WORD_BOUNDARY ʃ æ l oʊ WORD_BOUNDARY w ɔ t ə ɹ z WORD_BOUNDARY æ t WORD_BOUNDARY d ɛ p θ s WORD_BOUNDARY ʌ v WORD_BOUNDARY w ʌ n WORD_BOUNDARY d æ ʃ WORD_BOUNDARY t uː WORD_BOUNDARY m iː t ə ɹ z WORD_BOUNDARY θ ɹ iː WORD_BOUNDARY s ɛ v ə n WORD_BOUNDARY ɛ f t iː WORD_BOUNDARY iː k w ə l z WORD_BOUNDARY iː k w ə l z WORD_BOUNDARY iː k w ə l z WORD_BOUNDARY n æ t̠ʃ ə ɹ ɹ ə l WORD_BOUNDARY h ɪ s t ə ɹ ɹ i WORD_BOUNDARY iː k w ə l z WORD_BOUNDARY iː k w ə l z WORD_BOUNDARY iː k w ə l z WORD_BOUNDARY