Neogobius melanostomus (Pallas 1811)
- AUTHOR: Dr. Krzysztof E. Skora
AUTHORS ADDRESS: Hel Marine Biological Station, 84-150, Hel, P.O. Box 37,
tel.: +48 58 750836, fax: +48 58 750420,
e-mail: sekhel@halina.univ.gda.pl
CITATION OF THIS ENTRY: Skora, K., E. 1997. Neogobius melanostomus. In: Baltic Sea
Alien Species Database. S. Olenin, E. Leppakoski and D. Daunys (eds.).
INTERNET: http://www.ku.lt/nemo/mainnemo.html
TAXONOMY
| Typus | Chordata |
| Subtypus | Vertebrata |
| Superclassis | Gnathostomata |
| Classis | Osteichthys |
| Subclassis | Actinopterygii |
| Ordo | Perciformes |
| Subordo | Gobioidei |
| Familia | Gobiidae |
| Genus | Neogobius |
| Species | Neogobius melanostomus (Pallas 1811) |
Subspecies (?) in the Caspian Sea Neogobius melanostomus affinis Eischwald
- Gobius melanostomus Pallas 1811,
Gobius (Apollonia) melanostomus Pallas 1811
- Trevno popche (Bu), Schwarzmundgrundel, Kruglyak Grundel
(D), Round goby, Black spotted goby (En), Gobie ā taches noires
(Fr), Babka bycha, babka okragla (Pl), Guvid, Stronghil, Babca
neagrā (Ro), Bychok kruglyak, Chornorotyj bychok (Ru), Gobio
pintato (Sp)
IDENTIFICATION
- After Miller (1986) nape scaled completely, scales cycloid
on middle and anterior nape. Head depth 0.9 1.2 width. Inter orbit
four fifths to almost equalling eye diameter. Angle of jaws below
anterior quarter of eye. Snout 1.1 1.4 orbit. Upper lip narrowing
slightly to rear, with about half lateral preorbital area. Pelvic disc
0.6 0.8 abdomen length, anterior membrane width very shallow, rounded,
lateral lobes, if evident at all. Caudal peduncle depth about two
thirds own length. D1 VI (VVII); D2 I + 1416 (1316): A I + 1113
(1114); P 1819 (1720). Scales in lateral series 4955 (4557).
Vertebrae 3233 (3134). Colour: yellowishgrey, with lateral blotches;
first dorsal fin with large black spot in posterior part; breeding males are
black, with median fins whiteedged. Size: to 22 cm. (24.6 cm Lt, in
Gulf of Gdańsk)
Fig.1 Neogobius melanostomus (Pallas 1811) from the Gulf of
Gdansk (Lt 185 mm).
The figure does not show the changeable colour and
pattern of the fish.
Fig.2 Larvae and juvenile Neogobius melanostomus affinis
(after Koblickaja 1981)
- Species already present in the Baltic Sea,
with which an introducent have similar features, and therefore may be
mixed up
Fig.3 Gobius niger
Fig.4 Gobiusculus flavescens
Fig.5 Pomatoschistus microps
Fig.6 Pomatoschistus miutus
INTRODUCTION AND DISTRIBUTION
- First record from the Baltic Sea (year, area, reference):
- Year 1990,
Area Gulf of Gdańsk (Hel),
Reference Skóra K. E., Stolarski J. 1993 "New fish species in the
Gulf of Gdansk Neogobius sp [cf. Neogobius melanostomus
(Pallas 1811)]", in: Notes Bulletin of the Sea Fisheries
Institute 1 (128): 83.
- in the entire Baltic Sea No
in the area of primary introduction Yes
- Primary or secondary introduction into the Baltic:
- Primary, probably before 1987, into the harbours or
shipyard basins of Gdynia (Gulf of Gdansk) because the first individual
of this species, caught in 1990 in Hel, was age 3 or 4 according to
scale readings.
- Present distribution in the Baltic:
- In the Gulf of Gdańsk:
- In the entire Puck Bay:
- in the harbours of: Gdynia, Hel, Jastrania, Puck and out of them
(data from Hel Marine Station);
- in the coastal zone, of thr above harbours, and near the fishery
villages: Kuźnica, Chałupy, Swarzewo, Rzucewo, Osłonino, Rewa, Mechelinki, GdyniOksywie, GdyniaOrłowo and Gdynia Redłowo (data from Hel Marine Station),
- shoal area of Ryf Mew (data from Hel Marine Station)
- position 54° 31, 39 N and 18° 50, 47 E at depth =3134 m (data from Sea Fisheries Institute, Gdynia).
- Outside the Puck Bay:
- in the area of GdańskBrzeźno, GdańskWesterplatte (data from Sea Fisheries Institute and Hel Marine Station).
- Outside of the Gulf of Gdańsk:
- near Dębki. (data from Sea Fisheries Institute, Gdynia).
- Primary introduction (in Europe): a route of introduction:
-
The first transfer of this species outside its native biogeographic
range occurred in the Aral Sea (Miller 1986). However, the species died
out because of increasing salinity in this body of water (A. Neelov,
personal comm.).
N. melanostomus could have found its way into the Gulf of Gdansk
by means of ballast waters of vessels sailing along the line connecting
the Caspian and Black Seas with the Baltic, or directly through rivers:
from the Black Sea through the Dnieper, Pripet, Pina, Kanal Krolewski,
Bug, and Vistula. It is also possible that they reached the Baltic by a
longer route from the Sea of Azov through the Don to theVolga or from
the Caspian Sea through the Volga, Rybinskoe Reservoir, the Onega and
Ladoga Lakes and the Gulf of Finland. This second longer route seems
more likely. This is supported by the fact that N. melanostomus was
observed in the river Moskva (Sokolov et al. 1989). So far the presence
of these fish in other parts of the Baltic has not been observed; the
Gulf of Gdansk is their only habitat. Transport of eggs or larvae with
ballast waters seems more likely than the migration of fish. This
species is not a good "swimmer" and it is difficult to imagine the
fish covering such a long distance, leading mostly upstream.
Fig.7 Hypothetical route of N. melanostomustransfer
from its native habitat into the Gulf of Gdansk.
ABIOTIC PREFERENCES AND BIOLOGY
- In the area of origin
- Inshore, on coarse gravel, shelly and sandy bottom, to a depth of 20 m (50-60 m in winter, off Varna, Bulgaria); also lower and middle reaches of rivers, in only slightly brackish to freshwater (Miller 1986).
In the Baltic
- In the Gulf of Gdansk: on sandystony bottom, among mussel beds, marine
structures (piers, wharves), sunken objects. In the Puck Lagoon, which
is a part of the Puck Bay, juvenile stages inhabit muddysandy
humuscontaining bottom, overgrown with bethic flora.
- Reproduction, physiology, feeding strategy,
mobility level, etc.
- After Miller (1986) Reproduction: April to end of September
(Varna), MayJune (Romania), early April to August (Strait of Kerch)
but ending by July in Sea of Azov; repeat spawning, up to six times,
every 1820 days in captivity. Eggs ovoid, with sharp apex, about 3.9 x
2.2 mm, deposited under or between stones. Fecundity 3285221 at 713 cm.
Sexually mature at 34 years (males), 23 years (females).
Lifespan:
up to 4 years, but males after the spawning season.
Food: chiefly
bivalves, crustaceans (corophiid amphipods, decapods) and polychaetes;
also, small fish and chironomid larvae.
Based on the observation from two years (very warm seasons in 1994 and 1995), it was concluded that the spawning season of N. melanostomus in the Gulf of Gdansk extended from the end of April until the end of August/beginning of September. In captivity at water temperatures of 1819°C the incubation lasted from 17 to 19 days (Skora, unpublished). Fecundity values, calculated by Kuczynski (1995) for two 15 cm long females were 2700 and 3000 eggs/individual.
- a) positive and/or negative social and economic effects
- The consequences of the growth of this species population in the
Gulf of Gdañsk may be commercially favourable for local fishery and
anglers becausein a situation when many of traditionally caught species
disappear it may compensate for their absence.
This species has cobstituted most of gobiid catches in the Sea of
Azov, Romanian and Bulgarian waters (Miller 1986).
According to Svietovidow (1964) in the `30s and `40s in the Aral Sea
the catches of this species ranged from 2 to 35 thousand tons, while
in 1956, they amounted to almost 50 thousand tons. In the northern Black
Sea annual catches fluctuated at the level of 3 to 4 thousand tons (Fig.8).
Catch rates vary widely because of the stock size, predation by pike
perch and mortality due to the summer oxygen deficiency in water.
-
Fig.8 Cans with Round Goby in the Russian supermarket (Photo by S. Olenin)
It is uncertain whether the stock of N. mealnostomus will be that
numerous; food resources (abundance of mollusks) and lack of predators
are to the species advantage. For a year N. melanostomus has bee sold
in fish markets at 1.5 PLN/kg (0.6 $/kg). Bycatch rates of this species
during eeldirected catches with traps reach up to 50 kg/day/boat.
This fish becomes more and more often the main sporting species,
particularty in the Gdynia area.
-
b) impact on the ecosystem (physical displacement of, or predation
on native species; changes in autochtonous communities and food chains;
others)
- An increase in the number of N. melanostomus may bring about
farreaching changes in the ecosystem. This species may become a serious
competitor for food with other species of ichthyofauna of coastal zone
(especially crustaceans and molluscs feeders). Its hiding places will
overlap with those occupied by Zoarces viviparus and Gobius
niger. N. melanostomus, being abundant and accessible, will
become a new food item for other fish and birds. This will probably
result in reduced preying intensity on traditionally consumed major
species (sand eels, sprat, large crustaceans).
- Abundance in study area: quantitative data on
density/biomas and comparison to autochtonous species of the same
taxonomic/ecological group.
-
The abundance of N. melanostomus in the Gulf of Gdansk should
be considered as high and widespread. In the habitats optimal for this
species (among constructions reinforcing the beach, made of rocks) the
presence of even several individuals per 1 m2 od surface area was
reported (Redlarski A., Samsel J., viedeo films).
The remaining autecological features reveal that this species has
found adequate living condition in the Gulf of Gdansk. Its propagation
in our waters is aided by the food base, abundant in molluscs, which
are the main food component for this species. In the areas of its
natural habitat molluscs constitute from 46 to 98% of its diet
(Svetovidov 1969). Not without significance is also its optimum
spawning strategy (caring for the eggs, absence of the pelagic
phase during the larval stage), protecting embryos and juvenile
stages against predation by stickleback, dominant in the coastal
zone. Besides, the disappearance of large predators (cod, pike, eel,
seals) in the coastal zone nullifies the threat to adult individuals.
Another factor, which probably favourably influences the ability of
this pontocaspian species to settle in the Baltic, are symptoms of the
global warming.
REFERENCES
-
1. Crossman, E.J. Holm E., Cholmondeley R., Turininga K., 1992 First
record for Canada of the rudd Scardinus erythrophthalmus, and
notes on the introduced round goby, Neogobius melanostomus Can.
Field. Nat 106, 2: 206209.
2. Jude D.J., Reider R.H., Smith G.R., 1991 "First evidence of Gobiidae
in the Great Lakes basin. Conf. of the Int. Assoc. for great Lakes
Res. June 25 1991.
3. Jude D.J., Reider R.H., Smith G.R. 1992 "Establishment of Gobiidae
in the Great Lakes Basin" Can. J. Fish. Aquat. Sci. Vol. 49, 2: 416421.
4. Jude D.J., Jamssen J., Crawford G., (in press) Ecology distribution
and impact of the newly introduced round and tubenose gobies on the
biota of St. Clir and Detroit Rivers" In M. Munawar, T. Edsall and J.
Leach (eds) The lake Huron Ecosystem: Ecology, Fisheries and Management.
Ecovision World Monograph Series, S.P.B. Academic Publishing,
The Netherlands.
5. Grygiel W. 1995 Występowanie nowego gatunku babki Neogobius
melanostomus (Pallas 1811) w polskicj obszarach morskich.
Notatka w Zakladzie Biologii i Ochrony Zasobów MIR, Gdynia.
6. P.J. Miller 1986 "Gobiidae" in: "Fishes of the Northeastern
Atlantic and the Mediterranen", Vol III, P.J.P. Whitehead at al (ed):
10191086.
7. Müller H. 1983 "Fische Europeas" Neuman Verlag, Leipzig; 320.
8. Koblickaja A.F. 1981 "Opredielitiel molodii priesnowodnyh ryb"
Moskva. Legkaja i pischevaja promyslennost. 208.
9. Kuczyński J. 1995 Babka krągła Neogobius melanostomus
(Pallas 1811) emigrant z Basenu Pontokaspijskiego w Zatoce Gdańskiej.
Bull. SFI, Gdynia, 2(135): 6871.
10. Kuzancejev E.N. 1981 "Ryby Kaspijskogo morija" Moskva, Legkaja
i pischevaja promyslennost.
11. Skóra K.E., Stolarski J. 1993 New fish species in the Gulf
of Gdansk Neogobius sp [cf. Neogobius melanostomus (Pallas
1811), in: Notes Bulletin of the Sea Fisheries Institute 1(128): 83.
12. Skóra K.E., Stolarski J., 1993 "Neogobius melanostomus
(Pallas 1811) a new immigrant species in the Baltic Sea"
Proceedings of Second Estuary Symposium on Biology of Estuarine Species.
Gdańsk, Poland Oct. 1822 1993. AMBER (in press).
13. Skóra K.E., Stolarski J. 1994 "Neogobius melanostomus (Pallas
1811) new fish in the Baltic Sea". Poster, communicat (abstrakt),
The VIII European Congress of Ichthyology "Fishes and their
environment". Sep 25 Oct 2, 1994 Oviedo, Spain.
14. Skóra K.E., Stolarski J., 1995 "Round goby a fishy invader"
WWF Baltic Bulletin 1/95, :4647.