Background information and definitions
Biocides may offer a tool for localised eradication or population reduction of gobies, provided potentially negative effects on native species are carefully managed.
Whilst a number of different biocides may be considered for control of goby populations, no evidence has been found relating to detailed scientific study of any of these biocides to control an existing population. For example, delayed-release and/or pelleted formulations of Bayluscide® are said to have been used in the USA to selectively reduce populations of bottom-associated fish species such as the round goby Neogobius melanostomus (Clearwater et al. 2008). It is reported that the round goby is unable to detect Bayluscide® and that exposure for a few minutes is lethal to the round goby, even if the fishes are removed to freshwater immediately afterwards (Schreier et al. 2001). Of the four chemical piscicides registered for use in the USA, rotenone and antimycin A and are considered “general” piscicides, but no studies have been found of their effects on round goby. Studies have however been conducted on the effects of rotenone on other fish species. For example, in the UK, before-and-after studies have reported that rotenone successfully reduced or eradicated populations of topmouth gudgeon Pseudorasbora parva and fathead minnows Pimephales promelas from ponds and lakes (Britton et al. 2008; Britton et al. 2011).
The effect of saponins on other fish species has also been studied. For example, a study in New Zealand found that an increase in water temperature or a decrease in dissolved oxygen concentration increases the sensitivity of invasive African flathead goby Glossogobius giurus to saponins provided in the form of teaseed cake (Minsalan & Chiu 1986). African flathead goby were eliminated by an application of 15 mg/L teased cake (Minsalan & Chiu 1986). However, no evidence was captured on the impact of saponins on the round goby or the tubenose goby Proterorhinus marmoratus.
Britton R., Brazier M., Davies G.D. & Chare S.I. (2008) Case studies on eradicating the Asiatic cyprinid Pseudorasbora parva from fishing lakes in England to prevent their riverine dispersal. Aquatic Conservation: Marine and Freshwater Ecosystems, 18, 867-876.
Britton R., Copp G.H., Brazier M. & Davies G.D. (2011) A modular assessment tool for managing introduced fishes according to risks of species and their populations, and impacts of management actions. Biological Invasions, 13, 2847-2860.
Clearwater S.J., Hickey C.W. & Martin M.L. (2008) Overview of potential piscicides and molluscicides for controlling aquatic pest species in New Zealand. Science for Conservation, 283, 1-74.
Minsalan C.L.O. & Chiu Y.N. (1986) Effects of teaseed cake on selective elimination of finfish in shrimp ponds. Pp. 79–82 In Maclean J.L., Dizon L.B. & Hosillos, L.V. (Eds) The First Asian Fisheries Forum. Proceedings of the First Asian Fisheries Forum, Manila, Philippines, 26–31 May 1986. pp. 79-82.
Schreier T.M., Dawson V.K., Larson W.J. & Schleis S.M. (2001) Piscicides as an emergency tool for controlling range expansion of the round goby (Neogobius melanostomus) in the Illinois waterway. Abstracts from the 44th Conference on Great Lakes Research, June 10–14, 2001, Green Bay, IL. International Association of Great Lakes Research, Ann Arbour, MI. p.120