Black goby

D-Schwarzgrundel; GB-Black goby; DK-Sortkutling; PL-Babka czarna; LT-Juodasis grundalas; LV-Melnais jūrasgrundulis; EST-Must mudil; RU-Чёрный бычок; FIN-Mustatokko; S-Svart smörbult

Characters

1) Pelvic fins are fused to form a sucking disc.
2) Basis of both dorsal fins are touching each other.
3) Anterior upper part of first dorsal fin dark.
4) Fin rays of first dorsal fin often elongated.
●) Eyes standing near together.
●) Body colouration brown marmorated with dark spots; during spawning season males become dark-brown to black.
Usually up to 12 cm, max. up to 18 cm length.

Similar species

Round goby - dark spot on posterior lower part of first dorsal fin; scales not in front of level of preoperculum (vs. completely scaled neck in black goby).

Common goby - dorsal fins separated; body lighter in colouration.

Sand goby - dorsal fins separated; body light coloured; dark spot on posterior part of first dorsal fin.

Painted goby - dorsal fins separated; body lighter in colouration; two rows of dark spots on dorsal fins.

Biology

Lives on muddy-sandy grounds and in-between algae down to 40 m depth; often in brackish and also polluted water; spawns in the Baltic Sea between May and August, thereby attaching the eggs onto seashells. Males defend the spawn and fan fresh water to it.

Diet

Feeding on bottom-living organisms like worms and amphipods.

Importance

Due to their abundance an important prey for bigger, commercially important fish species like eel and cod; is used as bait fish.

Remarks

Gobiids resemble each other much; this holds especially true for poorly coloured specimens and juveniles. Often even specialist have much difficulties to clearly identify the species.