Bulletin
Zoologisch Museum
0]NIVERSITEIT VAN AMSTERDAM
Vol. 6 No. 3 1977
Furtherobservations on the range extension of the alienamphipod
Gammarus tigrinus Sexton, 1939, in the Netherlands
during the years 1974 to 1976
Jan Dieleman & Sjouk Pinkster
extension Abstract showed a rapid range of this species
(Nijssen & Stock, 1966, Pinkster & Stock, In the of 1967, autumn 1975 and in the spring of a
of the of new survey range Gammarus tigrinus Sex- Dennert et al., 1968, Gras, 1971,and Lourens,
ton, 1939, was carried out, especially at the bor- 1972). In a trade with 1973, new survey was spe- ders of the 1973 Considerable range. range exten-
sions were found in the north-eastern of cial the of the local parts the emphasis on position gam- province of Groningen, the Kampereiland (province marid fauna in the area now inhabited by G . ti- of in the Deltaic and Overijssel), Region in some
less isolated in more or areas the province of grinus (cf. Smit, During this survey only
Zuid-Holland. In most of the invaded newly areas minor range extensions were found. Notable new G. tigrinus has replaced the indigenous Gammarus
species. Sampling along the Dutch-German border localities were the Kralingse Plassen at Rotter-
revealed that has no invasion taken place from any dam, where an isolated was and of the German population found, populations. A fungus was found which
to be appeared pathogenic for G. tigrinus. the Haringvliet near Middelharnis, the southern-
most record of G. tigrinus in the Netherlands and
INTRODUCTION the first record for the Deltaic region. The most
this striking result of survey was the disappear-
After the introduction of the alien Gam—- of the amphipod ance indigenous species G. p. pulex (Lin- marus in the Netherlands duebeni tigrinus Sexton, 1939, naeus, 1758), G. Liljeborg, 1852, and G.
series (probably in 1964) a of sampling zaddachi from extensive surveys Sexton, 1912, areas, now 22
inhabited by G. tigrinus alone. (Benthuizer Vaart, Stotrpwijkse Vaart, Langeraarse
autuim in In 1975 and 1976 a new sampling sur- Pias, Kronme Mijdrecht).
out the boundaries of the In the of vey was carried along province Groningen (northeastern
distribution area of G. tigrinus as determined in Netherlands) the species has successfully invaded
1973. Mareover, intensive sampling was done along nearly all inland waters north of the line Gronin-
the eastern border of the Netherlands, to check a gen-Winschoten-Nieuweschans, except for sane pools
possible invasion of G. tigrinus from West Germany, and ditches behind the dikes of the Waddenzee.
where this species was purposely introduced in the South of this line no gammarid fauna was found at
rivers Weser and Werra (Schmitz, i960, Tesch & all, in spite of intensive sampling. Most probably
Pries, 1963> and Ruoff, 1968), while recently new this is caused by the heavy organic pollution and
found in localities were the Schlei (Bulnheim, the complete absence of oxygen during the sumner
1976). The total area, investigated during the months.
2. Netherlands there present survey, is indicated in fig. In the central part of the
in is only a small number of new localities: the
RANGE EXTENSION OF G. TIGRINUS IN THE AREAS Noordoost Polder, in the deltaic area of the river
INVESTIGATED IN 1975 AND 1976 IJssel and in some places just inside the dikes
along the former Zuyderzee (the parts now called
the considerable During present survey range ex- Eemmeer and Veluwemeer).
tensions have been found especially in the north- Intensive sanpling along the Dutch-German bor-
eastern and southwestern parts of the country. The der revealed, that no invasion had taken place
new localities, together with the distribution from any of the populations recently introduced
area found by Smit are illustrated in fig. in West Germany.
1. Table I summarizes the exact localities, dates
and chlorinities of the samples containing G. ti- THE INDIGENOUS SPECIES IN THE INVESTIGATED AREA
grinus.
Notable is the range extension in the south- Gammarus pulex pulex (Linnaeus, 1758) west on the islands of Voorne, Putten and Beijer- In the central part of the province of Zuid-Hol-
almost fauna is land, an area without any ganmarid land there still an extensive area in which G. at all before the introduction of G. (Den is the dominant the tigrinus p. pulex species, with excep-
Hartog, 1964, Smit, 1974). tion of some lakes in which G. tigrinus is the
In the Haringvliet, where it was found only only gairmarid. This area is characterized by the
once in G. has become in- of 1973, tigrinus a common presence many oligohaline, relatively unpollut- habitant and even inside the dikes on the island ed ditches with a well-developed and diverse flora of Goeree-Overflakkee the found in and fauna. In this of species was type habitat G. p. pulex can
In and one single locality. stony exposed places build up dense populations. The area is now almost along the border of the Haringvliet G. tigrinus conpletely surrounded by waters containing G. ti- was often found together with G. duebeni. More to grinus and it will be quite interesting to inves- the east, in the Hollands Diep and the Biesbosch tigate further developments there.
former tidal area) is (a freshwater there still Den Hartog (1964) expected a dispersion of G. no fauna at all. from the localities the Del- ganmarid p. pulex existing in
The in isolated population the Kralingse Plas- taic region and the small Brabantian rivers into
in (cf. sen Rotterdam Smit, has succesfully the Haringvliet, the Hollands Diep and the Bies- invaded the Bergscne Plassen and the Schiebroek- bosch after the closing of the sea arms and the sche Polder, further to the north at the city subsequent refreshing of these waters. However,
boundary. the reverse seems to happen: some localities in
In the central part of the of Zuid- Vilich G. found province formerly p. pulex was are now oc-
Holland some formerly inhabited localities, found cupied by G. tigrinus whereas the Brabantian riv- abandoned the during 1973 survey, were again occu- ers are so severely polluted that they act as an
by G. Noord A). In the effective barrier rather than pied tigrinus (Vliet, Geer, a way for disper-
several same area new localities were discovered sion. So it seems most likely that G. tigrinus 23
the almost from the will soon occupy the Hollands Diep and Bies- has now completely disappeared
in northern Deltaic the bosch since it is already abundant the Haring- region: it was found only on
island vliet. of Goeree-Overflakkee at chlorinitiesrang-
In the provinces of Priesland and Groningen G. ing from 3,000 to 10,000 mg/1. In the province of
to G. it has been G. in p. pulex is gradually loosing ground tigri- Groningen replaced by tigrinus
localities. nus (see also Smit, and now has almost com- many
pletely disappeared.
In the eastern part of the Netherlands, where
used be it has DISCUSSION G. p. pulex to a common species,
almost completely disappeared. The reason for this
found cannot be found in the competition with G. tigri- In his 1973 survey Smit (197*0 only some
nus but more likely in the progressive pollution minor range extensions of G. tigrinus, giving the
of the water systems in this region. In the north- impression that the situation was stabilizing af-
is in the ern part of the Veluwe area, where pollution ter the rapid expansion of G. tigrinus pro-
less G. is still the severe until now, p. pulex com- ceeding years. During present survey, however,
mon. considerable range extensions were found again in
the south-western as well as in the north-eastern
Gammarus duebeni duebeni Liljeborg, 1852 part of the distribution area. In the middle of the
took Smit already noticed the spatial separation country the only considerable range extension
of G. d. duebeni and G. tigrinus in the Buiten-IJ place in the Deltaic area of the river IJssel.
Like in near Amsterdam. A comparable situation can be the preceding years, mainly oligo-
found in Waterland (the area north of Amsterdam haline waters were occupied (table I), and there
with many ditches, canals and small lakes with are still no records of G. tigrinus from running
chlorinities of 500 to 1000 mg/1) where G. d. due- freshwater or from its original environment, the
beni lives on exposed, stony places, and G. tigri- tidal belt (Bousfield, 1958) (Holland, 1976, men-
nus lives in all other microhabitats. tioned one locality from a salt marsh along the
In the Haringvliet, where G. tigrinus has be- very polluted Mersey estuary in England). In some
is come a very common species, G. d. duebeni still areas G. tigrinus does not penetrate into clean,
found but and and only on exposed stony places oligohaline ditches, where G. p. pulex is abun-
even in these habitats it is rather scarce. The dant. The relatively low Cl-concentrations found
salinity might have reached too low values to per- in these areas (130 to 400 mg/1) cannot be the
mit successful reproduction here except during decisive factor in this respect, since G. tigri-
winter the months (see Pinkster, 1975, for the com- nus was often found at much lower chlorinities.
bined influence of temperature and salinity on re- Future observations as well as laboratory studies
production) . will be necessary to find an explanation for this
Compared with the situation found by Den Hartog phenomenon.
(1964) G. d. duebeni now inhabits a more restrict- Pinkster (1975) already discussed, that in
ed the northern Deltaic area in region. Only on oligohaline waters G. tigrinus has a much greater
the island of Goeree-Overflakkee, where ditches reproductive capacity than G. d. duebeni, G. zad-
and with of to pools a chlorinity 3,000 up 10,000 dachi and G. p. pulex. This is because of its fa-
mg/1 are still nornal, abundant populations of G. vourable reproduction period compared with G. d.
d. duebeni were found. duebeni and G. zaddachi, its short egg-incubation
In the of where G. d. due- with G. and G. province Groningen period corrpared d. duebeni p. pulex, beni still common in it was rather 1973, now was and its very short time to reach sexual maturity
in found one locality only, just behind the dike compared with all three species. In higher salin- of the Waddenzee. ities, when G. d. duebeni and G. zaddachi extend
their reproduction period to the sunmer months,
Gammarus zaddachi Sexton, 1912 this advantage of reproductive output of G. ti-
This species, once a normal inhabitant of the grinus diminishes. head of estuaries and of saline inland waters, Holland (1976) found the same pattern of dis- 24
tribution in England for the 4 species mentioned REFERENCES
above: G. zaddachi only in higher chlorinities
(2,000mg/land more), G. d. duebeni in chlorini- BOUSFIELD, E.L., 1958. Freshwater crustaceans of
America. - glaciated North Canad. Fid Nat., 72 ties down to 500 mg/1, and G. tigrinus in chlorin- (2): 55-113.
ities ranging from about 100 to several thousands BULNHEIM, H.P., 1976. Gammarus tigrinus, ein neu-
es Faunenelement der Ostseeförde Schlei. - Sehr, of G. is in waters in- rag/1. p. pulex very rare naturw. Ver. Schlesw.-Holst. 1»6: 79-8**. , brine fluenced by the of waste from the H.G. Tolerance differences and discharge DENNERT, , interspecific competition in three members of the Cheshire Salt Field.
- 1 genus Gammarus. Dierk. ¡tit ( ) : amphipod Bijdr. , Dennert demonstrated that interspecific 83-99-
DENNERT, H.G., A.L. DENNERT & J.H. STOCK, 1968. of aggression as a component interspecific compe- Range extension in 1967 of the alien amphipod, tition with could vary largely temperature and Gammarus tigrinus Sexton, 1939, in the Nether-
lands. - Bull. zool. Mus. Univ. Amsterdam, _1_ (7): salinity. At this moment a series of laboratory 79-80. determine experiments are performed to the role GRAS, J. M. J.F., 1971. Range extension in the pe-
riod 1968-1970 of the alien amphipod, Gammarus of aggression and voracity in the relation between tigrinus Sexton, 1939, in the Netherlands. -Bull, mentioned the four species above. zool. Mus. Univ. Amsterdam, 2 (2): 5-9-
HARTOG, C. DEN, 196k. The amphipods of the Deltaic Finally a short note on a fungus found to kill Region of the rivers Rhine, Meuse and Scheldt in
in the field the III. G. tigrinus both and the laboratory. relation to hydrography of the area. Part
Gammaridae. - Neth. J. Sea Res., 2_ (3): In the field dead specimens covered with the fun- HOLLAND, D.G., 1976. The inland distribution of
found and brackish-water in gus were especially in August September. Gammarus species the area of the
Mersey and Weaver River Authority. - Freshwat. In the laboratory this fungus rapidly killed all Biol., 6: 277-285.
of G. but G. in the extension alien specimens tigrinus, p. pulex LOURENS, J.H., 1972. Range of the
Gammarus tigrinus 1939, in the not amphipod Sexton, same basin was influenced at all. The fungus
Netherlands, in 1971. - Bull. zool. Mus. Univ. iden- was identified as Saprolegnia spec. Further Amsterdam, 2 (11): 115-120. NIJSSEN, H. & J.H. STOCK, 1966. The amphipod Gam- tification was inpossible as sexual reproduction the marus tigrinus Sexton, 1939, introduced in
stages were absent. So far no parasites or dis- Netherlands (Crustacea). - Beaufortia, (160): 197-206. eases have been reported for G. tigrinus from the PINKSTER, S., 1975. The introduction of the alien
Netherlands. amphipod Gammarus tigrinus Sexton, 1939 (Crusta-
in the Netherlands its cea, Amphipoda) and com-
petition with indigenous species. - Hydrohiol.
ACKNOWLEDGEMENTS Bull., 9 (3): 131-138.
PINKSTER, S. & J.H. STOCK, 1967. Range extension
in 1966 of the alien amphipod Gammarus tigrinus
The fieldwork was supported by a grant from the Sexton, 1939, in the Netherlands. - Beaufortia, JU (168): 81-86. Research Institute for Nature Management (Rijks- RUOFF, K., 1968. Experimentelle Untersuchungen
instituut voor Natuurbeheer). During the fieldwork über den in die Weser eingebürgerten amerikani-
schen Bachflohkrebs Gammarus tigrinus Sexton. - the authors were assisted by Annemarie Goedmakers, 13U-1 Arch. FischWiss., J9 (2-3): 58.
Natasa Dieleman-Jekos, Bert Pex, Bert Meijering, W. i960. Die von Gammarus SCHMITZ, , Einbürgerung
tigrinus Sexton auf dem europäischen Kontinent. - and Pero Versteeg. Mrs. drs. A.J. van der Plaats- Arch. 57 223-225. Hydrobiol. , (1-2):
Niterink of the Central Institute for Fungus Cul- SMIT, H., 197U. Extension de l'air de répartition
de Gammarus tigrinus Sexton en 1973 aux Pays-Bas, ture (Centraal Bureau voor Schinmelcultures) kind- et quelques remarques sur la concurrence avec les ly identification made the of the pathogenic fun- gammares indigènes (Crustacea, Amphipoda). -Bull, zool. Mus. Univ. Amsterdam, 1+ (5): 35-M. Smit us with some from gus . Harry provided samples TESCH, F. 8t G. FRIES, 1963. Die Auswirkungen des the of Voome and Putten. islands eingebürgerten Flohkrebs Gammarus, tigrinus Sexton
auf und Weser. Fischbestand die Fischerei in der -
Fischwirt, _1_1_: 1-8.
Jan DIELEMN & Sjouk PINKSTER
Institute of Taxonomic Zoology
University of Amsterdam
Plantage Middenlaan 53 Received : 1 December 1976
Amsterdam - the Netherlands Mailing date: 31 March 1977 25
TABLE I
NETHERLANDS FURTHER RECORDS OF GAMMARUS TIGRINUS IN THE (RANGE EXTENSIONS IN 1975 AND 1976)
Cl/1 Locality Municipality Accoirpanying Date mg
Gammarus species
Province of Zuid-Holland
Vlietland Voorschoten 16-X- 1975 190
Stompwijkse Vaart at
16-X- Stompwijk Leidschendam 1975 330
470 Ditch,2 km E of: Rockanj e 17-X- 1975
(along road to Hellevoet- sluis)
Moats of Hellevoetsluis Hellevoetsluis duebeni 17-X- 1975 400
Spui Nieuw Beij erland 17-X- 1975 270
Old harbour in village Piershil 17-X- 1975 360
28-X- 180 Bergsche Achterplas Rotterdam 1975
Ditch in the Schiebroekse
28-X- 160 polder at city boundary Rotterdam 1975
Binnengedijkte Maas Maasdam 30-X- 1975 130
Binnengedijkte Maas Mijnsherenland 30-X- 1975 130
Welvliet near Biert Geervliet 30-X- 1975 390
Ditch, 0.5 km SW of: Oudenhoorn 30-X- 1975 790
Vierambachtenboezem Geervliet 14-V- 1975*
Holle Mare Zwartewaal m-v- 1975*
Strijpsche Wetering Rockanj e 21-iv- 1976 430
Sluiswetering S of Tinte Oostvoome 21-iv- 1976 380
Hoofdwetering near Nieuwen- hoorn Hellevoetsluis 21-iv- 1976 l,l60
Haringvliet Stellendam 21-iv- 1976 320
Creek along Zuiderdiep Stellendam duebeni 21-iv- 1976 420
Haringvliet Stad aan 't duebeni 29-iv- 1976 280
Haringvliet
Haringvliet Den Bonne 1 29-iv- 1976 280
Ditch, 1.5 km
ESE of: Zuidland 29-iv- 1976 290
Creek along the Vuile Gat Goudzwaard 29-iv- 1976 280
continued overleaf
*) oarrples provided by Harry &nit 26
TABLE I, continued
Date Cl/1 Locality Municipality Accompanying mg
Gammarus species
Province of Zuid-HoI land
20-V 260 Langeraarse Pias Ter Aar p. pulex -1976
Benthuizer Vaart, 1.5 km W of: Benthuizen 20-V -1976 830
Province of Utrecht
Krorrme Mijdrecht at
Woerdense Verlaat Wilnis ll-VIII-1976 160
Noordoo8tpoIder
Canal along Manmouthweg,
2.5 km S of Marknesse Noordoostpolder 5-XI -1975 420
1)80 idem, 3 km N of Ens Noordoostpolder 5-XI -1975
Province of Overijssel
Canal fron Ossenzijl to
Steenwijk, S of Oldemarkt Steenwijkerwold 5-XI -1975 190
28-X Ganzediep near Grafhorst IJsselmuiden -1976 202
Veneriete near Kamperzee-
dijk-Oost Zwollerkarspel p. pulex 28-X -1976 198
Veneriete near Nieuwe
Wetering Zwollerkarspel 28-X -1976 150
Province of Friesland
False Poel Wijiribrit seradeel 22-VI -1976
Het km SE of: 220 Wije, 3 Wolvega p. pulex 5-XI -1975
4 of: Heerenveen Canal, km NE p. pulex 5-XI -1975 170
Province of Groningen
Canal at Slochteren Scbaapshok, p. pulex 7-XI -1975 340
Tennunterzijldiep at
Scheemderzwaag Scheemda 7-XI -1975 400
Termunterzijldiep at Termunten 7-XI -1975 1,100
Brackish water basin near
OterdunBrwarven Delfzijl 7-XI -1975 1,430
Termunterzijldiep E of
Wagenborgen Termunten 7-XI -1975 370
continued overleaf 27
TABLE I, continued
Locality Municipality Acconpanying Date mg Cl/1
Gammarus species
Province of Groningen
Ditch around Joh. Kerk-
hovenpolder, SE of Woldendorp Termunten 7-XI -1975 1,110
Ditch around Carel Coenraad-
polder Finsterwolde 7-XI -1975 1,480
Buiskoopdiep between Beerta
and Nw-Beerta Beerta 7-XI -1975 540
H60 Beersterdiep Beerta 7-XI -1975
Buiten Nieuwediep 2 km E of: Noordbroek 7-XI -1975 360
Nieuwe Ee, 1 km NE of: Adorp 20-IV -1976 29O
Boterdiep at Ellerhuizen Bedum zaddachi 20-IV -1976 220
Ditch at St. Annen Ten Boer 20-IV -1976 280
Ditch at Rottum Kantens 20-IV -1976 480
Ditch, 1 km N of Warffum 20-IV -1976 760
Oude Maar, 1 km S of: Uithuizen 20-IV -1976 530
Garsthuizer Maar, 1 km E
of Garsthuizen Kantens 20-IV -1976 27O
Spijkstermaar at Losdorp Bierum 20-IV -1976 330
Groote Heekt 2 km S of
Holwierde Bierum 20-IV -1976 28O
Damsterdiep Appingedam 20-IV -1976 360
Leermenstermaar 1 km S of
Leermens 't Zandt 20-IV -1976
Province of Noord-Hollcmd
Ditch in polder Huizer en
Naarder Aangerechten Blaricum 8-XI -1976 186
Moats E of Naarden Naarden 8-XI -1976 282
Province of Gelderland
Ditch behind dike of Eem-
meer, 1 km E of pumping- station in the Wiel Nijkerk 8-XI -1976 124
Gelderse Gracht near
Posthoorn Oosterwolde p. pulex 28-X -1976 62 28
1. Fig. New records in 1975 and 1976 of Gammarus tigrinus Sexton, in the Netherlands (each dot rep-
of The minimal resents a new locality or a group proximate localities). area occupied by the
is species at the end of 1973 hatched. Asterisks indicate formerly inhabited areas, aban-
doned in 1973, but now again occupied. 29
Fig. 2. Records of indigenous Gammarus species in the area investigated (hatched).