A school of goatfish working a sandy patch at the edge of a northern reef operates with the organised energy of a team that has divided responsibilities and is getting on with it. Several fish probe the substrate at once, chin barbels dragging through the sediment like instruments looking for a signal. Others hover in loose attendance. Nearby, a john dory watches from a polite distance, waiting for something to bolt. Upeneichthys lineatus is the only common goatfish in New Zealand, known locally as red mullet, and it earns both names. The body is moderately deep and laterally compressed, with coloration that is genuinely variable: pale cream to deep red, with blue and gold lines on the face, thin yellow stripes and blue spots along the flanks, and fins that can shift between colour phases depending on behaviour and mood. A resting fish often looks quite different from an actively foraging one. Two fleshy barbels hang from the chin, tucked into a groove when not in use, extended during feeding. These are chemosensory instruments capable of detecting buried invertebrates through several centimetres of sand, and they are the reason this family exists as a distinct group. The foraging behaviour is the most observable thing about goatfish. Schools move slowly over sandy and mixed substrates, each fish pushing its barbels into the sediment and tossing small puffs of disturbed material back through the gills. Anything edible that gets dislodged is taken immediately. The disturbance also benefits other species: small wrasse follow goatfish schools closely to intercept organisms flushed from the sand. John dory patrol the edges. Shags make occasional lunging passes from above. The goatfish school functions, in effect, as a mobile feeding event that draws a small but reliable audience. Distribution in New Zealand is concentrated in the northern North Island, from Northland through the Bay of Plenty and into the Marlborough Sounds. Populations are reliably found in sheltered harbours and at productive reef-sand margins where currents carry food across soft substrate. Two rarer species, the black-spot goatfish and the bar-tailed goatfish, are occasionally recorded but are not consistently present. The goatfish carries no threat classification in New Zealand and is not commercially targeted. Its significance is ecological rather than economic: a mid-level forager that turns sediment productively and supports a small community of opportunists in its wake. It does this continuously, without particular urgency, at every productive sandy margin in the northern coast.