Long-Term Effects of Ammonia on the Behavioral Activity of the Aquatic Snail Potamopyrgus antipodarum (Hydrobiidae, Mollusca)

Abstract

An appropriate approach to assess the effect of toxicants on aquatic animals is to monitor behavioral endpoints, as they are a link between physiological and ecological processes. A group that can be exposed longterm to low toxic concentrations is benthic macroinvertebrates, as their mobility in aquatic ecosystems is relatively limited. Therefore, the study of behavioral long-term effects in this group is suitable from an ecological point of view, as behavioral effects can appear before mortality. During the last decades there has been an increase in ammonia concentrations in freshwater ecosystems, threatening aquatic animals. The present study focuses on the long-term effects (40 days) of nonionized ammonia on the behavioral activity of the aquatic snail Potamopyrgus antipodarum. One control and three ammonia concentrations (0.02, 0.07, and 0.13 mg N-NH 3 /L) were used in triplicate, and the activity of snails (as mean time to start normal movement) and immobility were recorded for each treatment after 0, 10, 20, 30, and 40 days of continuous exposure to nonionized ammonia. The results show that P. antipodarum presented a high tolerance to lethal long-term effects of nonionized ammonia, as no animal died during the bioassay. However, the behavioral activity of snails was a very sensitivity endpoint, as a mean nonionized ammonia concentration of 0.07 mg N-NH 3 /L affected P.antipodarum. The results are discussed and compared with the available literature on long-term effects of ammonia on freshwater macroinvertebrates. Additionally, the ammonia water quality criteria, NOECs, LOECs, and long-term LCs are discussed on the basis of the current available data for freshwater macroinvertebrates.

Linking feeding inhibition with reproductive impairment in Gammarus confirms the ecological relevance of feeding assays in environmental monitoring

“…Furthermore, they are known to be sensitive to a wide range of chemical stressors, and many subindividual and individual markers have been developed in these species (reviewed in Kunz et al [10]). Feeding inhibition constitutes one of the first observed responses to environmental pollution [3,[11][12][13][14][15], and numerous studies have underscored that the feeding rate of gammarids can be inhibited by a wide range of chemical stressors in the laboratory and in the field (reviewed in Coulaud et al [3]). Feeding inhibition constitutes one of the first observed responses to environmental pollution [3,[11][12][13][14][15], and numerous studies have underscored that the feeding rate of gammarids can be inhibited by a wide range of chemical stressors in the laboratory and in the field (reviewed in Coulaud et al [3]).…”

“…Among the responses that can be monitored in gammarids, feeding inhibition is of great interest for multiscale assessment schemes. Feeding inhibition constitutes one of the first observed responses to environmental pollution [3,[11][12][13][14][15], and numerous studies have underscored that the feeding rate of gammarids can be inhibited by a wide range of chemical stressors in the laboratory and in the field (reviewed in Coulaud et al [3]). In addition, feeding inhibition occupies a central place in potential adverse outcome pathways, underlying the impact of contaminants across different levels of biological organization [6,16].…”

Toxic Effects of Fluoride Ion on Survival, Reproduction and Behaviour of the Aquatic Snail Potamopyrgus antipodarum (Hydrobiidae, Mollusca)

“…All dead animals were removed after observation. Immobile animals were considered dead if not retracting into the shell upon touching the operculum with forceps, but just as immobile if they do (Alonso and Camargo 2009). …”

“…The methodology was based on Alonso and Camargo (2009). For each replicate, five active individuals were randomly selected; each individual was picked up with forceps, which caused the retraction of the body into the shell and placed on the bottom of glass vessel (height, 55 mm; diameter, 77 mm; test water volume, 0.1 L), below a stereomicroscope equipped with an optic fibre beam.…”

“…Among benthic invertebrates, molluscs have been proposed as good indicators of environmental pollution, showing a high sensitivity to several toxic compounds (Oehlmann and SchulteOehlmann 2002;Valenti et al 2006;Duft et al 2007;Wang et al 2007). In the last years, the New Zealand mudsnail Potamopyrgus antipodarum (Hydrobiidae, Mollusca) has been amply used in ecotoxicology (Duft et al 2003;Mazurová et al 2008;Alonso and Camargo 2009;Gust et al 2009;Pedersen et al 2009) because of its parthenogenetic reproduction (Mazurová et al 2008) and its suitability for behavioural studies (Alonso andCamargo 2004, 2009). This species is currently under investigation as a standard test organism in the OECD test guideline programmme (OECD 2010).…”