Taxonomic name: Tridentiger trigonocephalus Gill, 1859
Synonyms: Gobius fasciapectoralis Fowler, 1938, Triaenophorichthys taeniatus Gunther, 1874, Triaenophorichthys trigonocephalus Gill, 1859, Triaenophorus trigonocephalus, Triaenophorus trigonocephalus Gill, 1858, Tridentiger bifasciatus Steindachner, 1881, Tridentiger bucco Jordan and Snyder, 1901, Tridentiger taeniatus Reeves, 1927, Tridentiger trigonocephalus Rendahl, 1924, Trifissus ioturus Jordan & Snyder, 1900
Common names: Chameleon goby (English), Japanese goby (English), Oriental goby (English), polosatyi trekhzubyi bychok (Russian-Russian Federation), shimahaze (Japanese-Japan), shimahaze (Japanese), striped goby (English), striped tripletooth goby (English-Russian Federation), trident goby (English)
Organism type: fish
Treidentiger trigonocephalus (the chameleon goby) is a native fish of Asia which is spread through ship ballast water or via eggs laid on hulls. It has established in California and Australia where it has been introduced. The main impact of this species is thought to be competition with native species.
The Chameleon goby is a grey-brown coloured goby with a white speckled head and two characteristic black stripes (Hayes et al. 2005). The stripes go from behind the eye to the tail fin and from the snout along the upper portion of pectoral fin to the tail fin. It is able to mask the black stripes by changing its colour to a grey-brown. There are two dorsal fins, which often have brown horizontal stripes and scattered white spots. The anal fin has a grey to orange stripe along the middle (NIMPIS 2006). Adult can grow to 120mm in length (NIMPIS 2006).
Eggs are somewhat pointed at one end (Breder and Rosen 1966, in FishBase 2006). There is a cluster of adhesive filaments at basal pole and the yolk is yellowish; with the late embryo pigmented on hindgut and ventral margin of tail (Watson 1996, in FishBase 2006).
estuarine habitats, lakes, marine habitats
Chameleon goby can live in freshwater, brackish and marine habitats, including artificial habitats. It lives in shallow water on (or near) the bottom, under rocks, in burrows, or in crevices (NIMPIS 2006). This bottom dweller may find a home in seagrass meadows (Kwak 2003). In its native range, the Chameleon goby is typically found in rocky areas of coastal bays and in freshwater (Fishbase 2006). In its introduced range in Australia it is found in both brackish and saltwater, while in USA it is found in brackish and freshwater environments (Fishbase 2006).
Chameleon goby have specific habitat requirements and it is therefore possible that they will compete with species sharing their preferred habitat (NIMPIS 2006).
Native range: Chameleon goby are native to Japan, China, Korea and Russia (NIMPIS 2006).
Known introduced range: Chameleon goby have been introduced to California, USA, and Australia (NIMPIS 2006).
Introduction pathways to new locations
Live food trade: Fertilised eggs of T. trigonocephalus may have been transported along with Pacific oysters in commerical shipments (Hayes et al. 2005).
Ship ballast water: Many introduced marine species are first recorded from regions with commercial ports and it is believed the large amounts of ballast water carried by international shipping is the most common way introduced marine species are transported (Carlton 1985, in Lockett and Gomon 2001). It has been suggested this has been a key vector in the transfer of several fish, including T. trigonocephalus (Lockett and Gomon 2001).
Ship/boat hull fouling: The eggs of T. trigonocephalus may be transported attached to fouling organisms on vessel hulls (Hayes et al., 2005).
Local dispersal methods
Boat: T. trigonocephalus may have been translocated by commercial or recreational vessels in southern Australia (Hayes et al., 2005).
Natural dispersal (local): T. trigonocephalus has self-established in USA (Fishbase, 2006).
Preventative measures: A two year study was undertaken for the Department of Environment and Heritage (Australia) by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) to identify and rank introduced marine species found within Australian waters and those not found within Australian waters.
All of the non-native potential target species identified in this report are ranked as high, medium and low priority, based on their invasion potential and impact potential. Tridentiger trigonocephalus is identified as one of ten potential domestic target species most likely to be spread to uninfected bioregions by shipping. A hazard ranking of potential domestic target species based on invasion potential from infected to uninfected bioregions identifies T. trigonocephalus as a 'low priority species' - these species have a low impact potential and a low invasion potential relative to the other domestic non-native species identified in the report.
For more details, please see Hayes et al. 2005.
The rankings determined in Hayes et al. 2005 will be used by the National Introduced Marine Pest Coordinating Group in Australia to assist in the development of national control plans which could include options for control, eradication and/or long term management.
The Chameleon goby mostly takes its prey from within the sediment and may consume large numbers of polychaetes, feeding mainly at night (Kwak 2003). Stomach contents have also been found to include crab larvae and caprellid amphipods (Kwak 2003).
Male and female Chameleon goby are separate, and eggs are laid during spring and summer. Eggs are deposited in nests which are guarded by the male (Breder and Rosen 1966, in FishBase 2006). Eggs take nine to 10 days to hatch. Females are able to spawn up to 10 times within a breeding season, which is from March through to November in the USA (FishBase 2006). In Japan, temperatures during the breeding season are between 18°C to 26°C.
Chameleon gobies are relatively short-lived, reaching sexual maturity within one year and living up to three years.
Compiled by: IUCN/SSC Invasive Species Specialist Group (ISSG) with support from La Fondation d'entreprise Total
Last Modified: Wednesday, 10 January 2007