Black Goby
Gobius niger
Frillfin Goby
Bathygobius soporator
About
The frillfin goby is a small, sharp-eyed fish that grows to about 15 cm and rules the tide pools and rocky shallows it calls home, rarely straying far from one patch of shore for long.
Also known as: brant
- Length
- 15 cm
- Depth
- up to 16 m
How to tell it apart
Many small gobies look alike on sand and rock, but on the frillfin goby the upper rays of each pectoral fin are not webbed together, giving the fin a frayed, fringed edge when it fans out.
Appearance
This goby is dark, with a mottled pattern of black, gray, and tan broken by three broad, slanted dark bars and faint pale stripes along its sides. Its eyes and cheeks look large for its body. The two dorsal fins are thin and gray-green, while the tail, anal, pectoral, and pelvic fins are a see-through yellow, and the head and pectoral fin bases carry white spots.
Habitat
It lives on sand and mud bottoms and in rocky tide pools, mangrove edges, and sheltered seagrass beds close to shore. It tolerates a wide range of salt levels, from full seawater to brackish creeks and even fresh water.
Breeding
A female lays her eggs on a sheltered hard surface, sometimes inside an empty shell. A male mates with several females, and each one leaves her eggs in a single spot for him to guard. These males can be very territorial and chase off intruders near the nest.
Did you know?
This goby can build a mental map of the tide pools around it, letting it leap accurately from one pool to the next at low tide instead of risking a jump onto dry rock.
Log it in Into the Blue
Describe what you saw and we name it, then keep every species you find in your Oceandex.
