Habitat use of invasive monkey goby (Neogobius fluviatilis) and pumpkinseed (Lepomis gibbosus) in Lake Balaton (Hungary): a comparison of electrofishing and fyke netting

Abstract

Detailed knowledge on the habitat preference of invasive fishes and the bias of different fishing methods in determining their population dynamic parameters are essential in fisheries management, ecology and conservation. This study was conducted to determine the habitat use and length frequency distribution of the invasive monkey goby and pumpkinseed in the littoral zone of Lake Balaton (Hungary) using two different sampling methods, electrofishing and fyke netting. In general, both species preferred anthropogenically modified habitat types (rip-rap shorelines and harbours) compared with natural reed habitats with silty-sand bottom. Length frequency distribution data showed significant between-gear differences, since electrofishing resulted in the capture of larger individuals in greater proportion than fyke nets for both species. This study, which includes the first detailed data about the habitat use of the highly invasive monkey goby in lakes, suggests that invasive species may benefit from the alteration of the littoral zone. It also highlights that reliance on single gear surveys can be misleading in assessing habitat use and population structure of invasive fishes.

Effects of Turbidity and Habitat Complexity on the Foraging Behavior of the Black Bullhead (Ameiurus melas)

“…Black bullheads are not known as ambush predators however, thus a more complex habitat offering various options to utilize as shelters is probably more profitable for the gobies to incorporate in their predator evasion behavior. In Lake Balaton, where the individuals for this experiment were caught, tubenose gobies use rip-rap habitats extensively (Czeglédi et al, 2019) and the individuals caught for this experiment were exclusively from this habitat. Tubenose gobies' 13 use of rocks as shelters is a basic behavioral pattern.…”

“…Consequently, we offered them tubenose gobies, Proterorhinus semilunaris (Heckel, 1837), alive and as fresh carcass simultaneously under different levels of turbidity and habitat 6 complexity. Both species are bottom dwellers, and can be found in the same freshwater ecosystems across Central Europe (Kováč, 2015;Musil, Jurajda, Adámek, Horký, & Slavík, 2010) including Lake Balaton, the largest shallow lake in Central-Europe, where they cooccur in the same habitat (Czeglédi et al, 2019), indicating a high likelihood of trophic interactions between them. Scavenging along with predatory behavior of black bullheads has been suspected in natural environments (see e.g.…”

First genetically verified occurrence of Ligula pavlovskii outside its native range and characteristics of its infection in Neogobius fluviatilis

“…Eudiaptomus gracilis is the most favourable host for L. intestinalis (Loot et al, 2001), a closely related species to L. pavlovskii, suggesting the zooplankton community to be ideal for the development of the latter. Its fish host, the monkey goby is widespread in various habitat types of the entire lake (Czeglédi et al, 2019), and there are also numerous piscivorous waterbird species which commonly feed on fish from the lake (Kovács, 2017). According to these, the continuation of the parasite's life cycle is guaranteed in Lake Balaton.…”

“…Since then the species became one of the most abundant non-native fish in the littoral zone of the lake (Czeglédi et al, 2019). During a fish survey conducted in the littoral zone of Lake Balaton in 2017, we found widespread tapeworm infection in monkey gobies.…”

New record of metacercariae of the North American Posthodiplostomum centrarchi (Digenea, Diplostomidae) in pumpkinseed (Lepomis gibbosus) in Hungary

“…After the detection of the first metacercariae in pumpkinseed, our research group started to study the parasite fauna of the pumpkinseeds in Lake Balaton and in its outflow, the Si o channel (Table 1). In the littoral zone of Lake Balaton, the pumpkinseed is the most abundant non-native fish species (Czegl edi et al, 2019). Eighteen pumpkinseed specimens derived from the River Danube at Szentendre and a single specimen from the River Ipoly at Ipolyt€ olgyes was examined (Table 2).…”