Day Shift

White Mouthed Moray EelPeacock flounder
Kingdom: Animalia Phylum: Chordata Subphylum: Vertebrata Class: Osteichthys Family: Bothidae Genus: Bothus Species: mancus
Scientific name: Bothus mancus
Common name: Peacock flounder
Hawaiian name: 'Ui'ui, Paki'i, Paku

Peacock flounders are handsome fish with blue-colored O-shaped markings on their upper side and three distinct darker blotches along the lateral line. The males sport a long pectoral fin that streams out above them like a plume as they swim. They are found throughout the Indo-Pacific between 30 degrees North to 35 degrees South.

Peacock flounder are among the so-called left eye flounders because, during their metamorphosis from fish larvae to the adult form, their right eye migrates to the left-hand side of their head and their body flattens so that they live, lying on their right hand side. This adaptation is perfected for living on or near sandy seafloors. They can bury themselves in the sand and lie concealed with just their eyes protruding looking up into the water column to watch for predators or prey.

But for their superb adaptations to this environment Peacock flounders would be vulnerable. Their sharp color vision enables them to visually match the substrate on which they are resting. Their skin is covered with pigment-laden cells called chromatophores controlled by the central nervous system. Their eyes collect information about the color of the background surrounding them and their brains interpret the information dictating which chromatophores should expand or contract. Pigment may coalesce into the center, making the cell go pale, or alternatively expand to radiate color. In this way these fish can make all the color variations necessary for them to exactly match their background. Scientists have discovered that these fish learn their background configurations that make subsequent matches swifter. Six sets of independently controlled skin structures can make countless designs. To improve their camouflage the edges of the flounder are fringed by anal and dorsal fins that hug the substrate closely like a curtain thereby eliminating the shadow of the animal as it lies on the seafloor.

Flounders are active during the day and also, reportedly, at night. They feed mainly on small, sardine-like fishes, crabs and shrimps near the seafloor, although they have been observed swimming to the surface at night to scoop up prey. The males are larger than the females and defend sizeable territories (50-350 square meters) within which their harem of females maintain their own smaller territories. The male patrols his territory during the day, visiting each of the females to spawn every evening during the season. Peacock flounders breed in late winter and early spring during which time the female may releases several million eggs. The fertilized eggs float close to the surface where they are carried away by the currents, to hatch out in 15 days.

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