Metazoa parasites of the invasive round goby Apollonia melanostoma (Neogobius melanostomus) (Pallas) (Gobiidae: Osteichthyes) in the Gulf of Gdańsk, Baltic Sea, Poland: a comparison with the Black Sea

Abstract

The known metazoa parasite fauna of the invasive round goby Apollonia melanostoma (formerly Neogobius melanostomus) consists of 12 species. The core of the parasite fauna comprises two species: Cryptocotyle concavum and Diplostomum spathaceum; secondary species are absent; satellite species include Cercariae gen. sp. and Ergasilus sieboldi; rare species are Acanthocephalus lucii, Anguillicola crassus, Bothriocephalus sp., Dichelyne minutus, Hysterothylacium aduncum, Pomphorhynchus laevis, Piscicola geometra, and Tylodelphys clavata. Fifty percent of metazoa parasites that occurred in the invasive round goby in the Gulf of Gdańsk (an invasion that was first detected in 1990) are also typically found in the native Gulf of Gdańsk gobiids. The round goby hosts common fish parasite species: C. concavum and D. minutus, but none that are unique to the species and no Ponto-Caspian parasites. Notably, the parasite species of the invasive round goby in the Gulf of Gdańsk includes species that are atypical for this species in its native habitat. In its new habitat, the round goby variously serves the roles of definitive, second intermediate, and paratenic host for different parasite species. The fish species is involved in a parasitic system that includes fish-eating birds, fishes of different ecological groups (predatory, planktivorous, and benthivorous), and invertebrates.

The first record of Piscicola pojmanskae Bielecki, 1994 in the Gulf of Gdańsk (the southern Baltic Sea) with species characteristics distinguishing it from Piscicola geometra (Linnaeus, 1758)

“…Underwater vegetation and blue mussel beds are typical habitats for small fish like gobies and sticklebacks (Jackowski 2002, Sapota 2004, Nohrén et al 2009). In the Bay of Puck, P. geometra was also found directly on the skin of round goby Neogobius melanostomus (Pallas, 1814) (Kvach & Skóra 2007) and stickleback Gasterosteus aculeatus aculeatus Linnaeus, 1758(Morozińska-Gogol 1999. In other areas of the Baltic Sea, the species was also found on the skin of eel Anguilla anguilla (Linnaeus, 1758) (Rolbiecki & Rokicki 2006), ninespine stickleback Pungitius pungitius (Linnaeus, 1758), viviparous eelpout Zoarces viviparus (Linnaeus, 1758) (Zander et al 1999), and Baltic flounder Platichthys flesus (Linnaeus, 1758) (Køie 1999).…”

Infection rates and prevalence of metazoan parasites of the non-native round goby (Neogobius melanostomus) in the Baltic Sea

“…Conversely, the racer goby (Babka gymnotrachelus, Kessler, 1857) has lower parasite richness in the native than in the invasive range (Kvach et al, 2014). Many previous results, in addition to the above, show that the round goby may be benefitting from decreased parasite load, supporting the enemy release hypothesis (ERH) (Kvach, 2001;Kvach & Skóra, 2006;Francová et al, 2011;Emde et al, 2012).…”

“…Studies focusing on round goby parasites in the Baltic Sea have been quite few, spatially limited to local studies on German, Polish and Lithuanian populations and completely lacking in the northern Baltic Sea (Kvach, 2001(Kvach, , 2004aKvach & Skóra, 2006;Rakauskas et al, 2008;Kvach & Winkler, 2011). The aim of the present study was to identify, quantify and compare the most common metazoan parasites (concentrating on metazoan endoparasites) infecting the round goby in four distinct locations in the Baltic Sea.…”

“…time since introduction, is often reflected in the parasite loads as the infection rates increase the older the population. This has been true, for example, in the Gulf of Gdansk, where the parasite abundance of the round goby increased from six species in the first studies (Rokicki & Rolbiecki, 2002) to at least 12 metazoan parasite species by 2006 (Kvach & Skóra, 2006). In the most recently established populations, the infection rates are presumably still low due to fewer parasitic species adapted to this new host.…”

“…Many researchers have also suggested the lack of natural enemies as a major contributing factor (Sapota & Skora, 2005;Kvach & Skóra, 2006;Kvach & Stepien, 2008;Gendron et al, 2012). Parasites are important biological regulators and occur as an inherent part of any biological community (e.g.…”