Changes in the fish community of the Ömerli Reservoir (Turkey) following the introduction of non-native gibel carp Carassius gibelio (Bloch, 1782) and other human impacts

Abstract

Gracilaria vermiculophylla, a red macroalga from the West Pacific, was discovered in western Germany (the Wadden Sea) in 2002 and has since also been observed in Sweden (from about 70 km south to about 80 km north of Göteborg), Denmark (Wadden Sea, Horsens Fjord, Limfjorden, Vejle Fjord, Holckenhavn Fjord, Øster Hurup Harbor) and eastern Germany (Kiel Bay). Today, less than 5 years following its first observation in the Wadden Sea the invader is common in many invaded regions, often being amongst the most abundant macroalgal species. G. vermiculophylla is successful in shallow protected soft-bottom estuaries and bays, typically in association with ubiquitous native invertebrates (lugworms, tube-building worms, mussels, cockles, snails). The invertebrates provide substratum for holdfast attachment and thalli incorporation, most likely increasing the stability of local G. vermiculophylla populations. We hypothesize that this substratum provision is highly important for its general invasion success. We also confirm that G. vermiculophylla can maintain growth at all salinities experienced along Danish coastlines (8.5-34 psu). In addition, laboratory experiments indicate that the ubiquitous grazer Littorina littorea has the potential to control G. vermiculophylla growth under specific environmental conditions, but also that L. littorea may facilitate small-scale dispersal within invaded locations, because grazing increases thalli fragmentation rates. Given its widespread distribution, rapid range expansion, and known ecological traits, G. vermiculophylla is clearly a permanent resident of northern European waters.

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“…Didham et al (2005) discussed how dominance of an exotic could be an indirect consequence of habitat modification driving biodiversity loss of native species. Prussian carp is recorded in high abundance (Gaygusuz et al, 2007) in invaded environments including this study. Our study indicates that Prussian carp, with its high diet plasticity, will increase in the future, facilitated by its high dominance, rapid growth and reproductive characteristics, with potential indirect consequences for native communities.…”

“…The rapid expansion and high abundance of Prussian carp in Turkey and also in some parts of Europe makes it problematic (Özcan, 2007;Gaygusuz et al, 2007;Lusková et al, 2010;Liasko et al, 2011;Tarkan et al, 2012). Recent studies have focused on the possible negative impact of this species to distribution (Özcan, 2007), abundance (Gaygusuz et al, 2007;Perdikaris et al, 2012), reproduction (Aydın et al, 2011) and some growth parameters (Leonardos et al, 2008;Tarkan et al, 2012).…”

“…Recent studies have focused on the possible negative impact of this species to distribution (Özcan, 2007), abundance (Gaygusuz et al, 2007;Perdikaris et al, 2012), reproduction (Aydın et al, 2011) and some growth parameters (Leonardos et al, 2008;Tarkan et al, 2012). The possible negative effects of Prussian carp on water quality and fish fauna have also been discussed (Crivelli, 1995;Leonardos et al, 2001;Povž and Šumer, 2005;Emiroğlu et al, 2012;Kırankaya and Ekmekçi 2013).…”

Several Growth Characteristics of an Invasive Cyprinid Fish (Carassius gibelio Bloch, 1782)

“…The presence of gibel carp in the Turkey was not recognized until the 1980s (Baran and Ongan, 1988), probably due to its strong ppheotypicalotypical resemblance to the Carassius species introduced to Turkey: crucian carp Carassius carassius (L., 1758), and goldfish Carassius auratus (L., 1758). With developments in the identification of Carassius species, distribution of crucian carp in Turkey is presently thought to include both the Thrace region and the entire Anatolian Peninsula (Gaygusuz et al, 2007).…”

Occurrence, dispersion and habitat preferences of Amur sleeper (Perccottus glenii) in oxbow lakes of a large river and its tributary

“…Evaluation of the impact of invasive species on ecosystems is extremely difficult and often requires knowledge of the ecosystem existing before the occurrence of the invasive species and a long observation period after its appearance (Lorenzoni et al 2006;Gaygusuz et al 2007). Assessments can be made by monitoring the ecosystem and estimating biodiversity parameters.…”