Dreissenid (quagga and zebra mussel) veligers are adversely affected by bloom forming cyanobacteria (original) (raw)
Related papers
Journal of Plankton Research, 2005
Colony forming and toxic cyanobacteria form a problem in surface waters of shallow lakes, both for recreation and wildlife. Zebra mussels, Dreissena polymorpha, have been employed to help to restore shallow lakes in the Netherlands, dominated by cyanobacteria, to their former clear state. Zebra mussels have been present in these lakes since they were created in the 19th century by the excavation of peat and are usually not considered to be an invasive species. Most grazing experiments using Dreissena have been performed with uni-cellular phytoplankton laboratory strains and information on grazing of larger phytoplankton taxa hardly exists. To gain more insight in to whether D. polymorpha is indeed able to decrease cyanobacteria in the phytoplankton, we therefore performed grazing experiments with zebra mussels and two species of cyanobacteria, that greatly differ in shape: colony forming strains of Microcystis aeruginosa and the filamentous species Planktothrix agardhii. For both species a toxic and a non-toxic strain was selected. We found that zebra mussels cleared toxic Planktothrix at a higher rate than non-toxic Planktothrix, toxic or non-toxic Microcystis. Clearance rates between the other strains were not significantly different. Both phytoplankton species, regardless of toxicity, size and shape, were found in equal amounts (based on chlorophyll concentrations) in the excreted products of the mussels (pseudofaeces). The results show that zebra mussels are capable of removing colonial and filamentous cyanobacteria from the water, regardless of whether the cyanobacteria are toxic or not. This implies that the mussels may be used as a biofilter for the removal of harmful cyanobacterial blooms in shallow (Dutch) lakes where the mussels are already present and not a nuisance. Providing more suitable substrate for zebra mussel attachment may lead to appropriate mussel densities capable of filtering large quantities of cyanobacteria.
Freshwater Science, 2018
Quagga mussels (Dreissena rostriformis bugensis) are highly fecund broadcast spawners invasive to freshwaters of North America and western Europe. We hypothesized that environmental cues from phytoplankton can trigger gamete release in quagga mussels. Nutritious algae may stimulate dreissenid spawning, but less palatable food, such as bloom-forming cyanobacteria, could be a hindrance. The objective of our study was to test whether exposure to cyanobacteria can inhibit quagga mussel spawning and fertilization. We assessed spawning in the presence of serotonin, a known spawning inducer, where adult quagga mussels placed in individual vials were exposed to 13 cyanobacteria cultures and purified algal toxin (microcystin-LR) with artificial lake water as the control. Fertilization success was evaluated by combining eggs with sperm in conjunction with cyanobacteria, and enumerating zygote formation marked by cellular cleavage. Several cyanobacterial strains reduced spawning and fertilization success, but microcystin-LR had no effect. Fertilization was more sensitive to cyanobacteria than gamete release. Only 1 culture, Aphanizomenon flos-aquae, inhibited spawning, whereas 6 cultures consisting of Anabaena flos-aquae, Dolichospermum lemmermanii, Gloeotrichia echinulata, Lyngbya wollei, and 2 Microcystis aeruginosa isolates reduced fertilization rates by up to 44%. The effects of cyanobacteria on reproduction in invasive freshwater mussels in the wild have not yet been identified. However, our laboratory studies show that concentrations of cyanobacteria that are possible during bloom conditions probably limit reproduction. Reproductive consequences on wild populations may become more prevalent as cyanobacteria blooms occur earlier in the year, making overlap between blooms and mussel spawning more common. Describing the mechanism by which cyanobacteria inhibit spawning and fertilization could reveal novel control methods to limit reproduction of this invasive species.
Canadian Journal of Fisheries and Aquatic Sciences, 2001
Microcystis aeruginosa, a planktonic colonial cyanobacterium, was not abundant in the 2-year period before zebra mussel (Dreissena polymorpha) establishment in Saginaw Bay (Lake Huron) but became abundant in three of five summers subsequent of mussel establishment. Using novel methods, we determined clearance, capture, and assimilation rates for zebra mussels feeding on natural and laboratory M. aeruginosa strains offered alone or in combination with other algae. Results were consistent with the hypothesis that zebra mussels promoted blooms of toxic M. aeruginosa in Saginaw Bay, western Lake Erie, and other lakes through selective rejection in pseudofeces. Mussels exhibited high feeding rates similar to those seen for a highly desirable food alga (Cryptomonas) with both large (>53 m m) and small (<53 m m) colonies of a nontoxic and a toxic laboratory strain of M. aeruginosa known to cause blockage of feeding in zooplankton. In experiments with naturally occurring toxic M. aeruginosa from Saginaw Bay and Lake Erie and a toxic isolate from Lake Erie, mussels exhibited lowered or normal filtering rates with rejection of M. aeruginosa in pseudofeces. Selective rejection depended on "unpalatable" toxic strains of M. aeruginosa occurring as large colonies that could be rejected efficiently while small desirable algae were ingested.
Canadian Journal of Fisheries and Aquatic Sciences, 2011
Microcystis aeruginosa, a planktonic colonial cyanobacterium, was not abundant in the 2-year period before zebra mussel (Dreissena polymorpha) establishment in Saginaw Bay (Lake Huron) but became abundant in three of five summers subsequent of mussel establishment. Using novel methods, we determined clearance, capture, and assimilation rates for zebra mussels feeding on natural and laboratory M. aeruginosa strains offered alone or in combination with other algae. Results were consistent with the hypothesis that zebra mussels promoted blooms of toxic M. aeruginosa in Saginaw Bay, western Lake Erie, and other lakes through selective rejection in pseudofeces. Mussels exhibited high feeding rates similar to those seen for a highly desirable food alga (Cryptomonas) with both large (>53 m m) and small (<53 m m) colonies of a nontoxic and a toxic laboratory strain of M. aeruginosa known to cause blockage of feeding in zooplankton. In experiments with naturally occurring toxic M. aeruginosa from Saginaw Bay and Lake Erie and a toxic isolate from Lake Erie, mussels exhibited lowered or normal filtering rates with rejection of M. aeruginosa in pseudofeces. Selective rejection depended on "unpalatable" toxic strains of M. aeruginosa occurring as large colonies that could be rejected efficiently while small desirable algae were ingested.
Toxins, 2020
Toxic cyanobacterial blooms are a major contaminant in inland aquatic ecosystems. Furthermore, toxic blooms are carried downstream by rivers and waterways to estuarine and coastal ecosystems. Concerning marine and estuarine animal species, very little is known about how these species are affected by the exposure to freshwater cyanobacteria and cyanotoxins. So far, most of the knowledge has been gathered from freshwater bivalve molluscs. This work aimed to infer the sensitivity of the marine mussel Mytilus galloprovincialis to single as well as mixed toxic cyanobacterial cultures and the underlying molecular responses mediated by toxic cyanobacteria. For this purpose, a mussel exposure experiment was outlined with two toxic cyanobacteria species, Microcystis aeruginosa and Chrysosporum ovalisporum at 1 × 105 cells/mL, resembling a natural cyanobacteria bloom. The estimated amount of toxins produced by M. aeruginosa and C. ovalisporum were respectively 0.023 pg/cell of microcystin-LR ...
Environmental Pollution, 2009
Proliferations of toxic cyanobacteria may alter the structure of mollusc communities with cyanotoxin accumulation depending on age and taxon. a b s t r a c t Community structure and microcystin accumulation of freshwater molluscs were studied before and after cyanobacterial proliferations, in order to assess the impact of toxic blooms on molluscs and the risk of microcystin transfer in food web. Observed decrease in mollusc abundance and changes in species richness in highly contaminated waters were not significant; however, relative abundances of taxa (prosobranchs, pulmonates, bivalves) were significantly different before and after cyanobacterial bloom. Pulmonates constituted the dominant taxon, and bivalves never occurred after bloom. Microcystin accumulation was significantly higher in molluscs from highly (versus lowly) contaminated waters, in adults (versus juveniles) and in pulmonates (versus prosobranchs and bivalves). Results are discussed according to the ecology of molluscs, their sensitivity and their ability to detoxify.
Freshwater Biology, 2013
1. Toxic cyanobacterial blooms and biological invasions are major threats to freshwater systems worldwide. While usually dealt with independently, the two threats can interact to produce synergistic or antagonistic outcomes. The aim of this survey is to analyse interactions between the cyanobacterium Microcystis spp. and the Asian invasive mussel Limnoperna fortunei. 2. On the basis of 9 years of observational data in a large subtropical reservoir (Salto Grande, Argentina-Uruguay), we analyse causal relationships between recurring summer-early autumn blooms of Microcystis spp. and recruitment by L. fortunei. Reproduction of the mussel was interrupted during dry summers (January-April), coinciding with periods of peak Microcystis spp. growth and low water discharge (which favours build-up of algal biomass). On the other hand, wet summers with high discharge rates were characterised by low Microcystis spp. densities and high numbers of L. fortunei larvae in the water column. 3. Of the seven South American waterbodies investigated, Salto Grande was the only one with very marked cyanobacterial blooms and where larval numbers decrease to near zero during January-April; in all others, reproduction peaks in January-April. 4. The assumption that microcystin-producing algae are responsible for these troughs during periods when elsewhere larvae are very abundant was reinforced by experimental results indicating that microcystin-LR is highly toxic to the mussel's larvae, eliminating 58-100% of animals in 48 h at 10-20 lg L À1. 5. Paradoxically, high concentrations of microcystin in water are probably partly due to L. fortunei's own activity, which enhances growth of Microcystis spp. through modification of nutrient concentrations, selective grazing of solitary Microcystis spp. cells over colonial ones and production of chemical cues that trigger the formation of colonies. 6. These interactions have important implications for the management of biofouling of industrial raw cooling water facilities by the byssate mussels, as well as policies oriented at curtailing the spread of the invasive bivalve.
Estuaries and Coasts, 2007
The introduction of invasive bivalves such as the zebra mussel (Dreissena polymorpha) can have profound effects on aquatic ecosystems, including decreases in phytoplankton biomass and changes in the taxonomic composition of phytoplankton. Zebra mussel introductions have been associated with increased dominance of cyanobacteria, especially Microcystis, but this change may depend on interacting physical, chemical, or biotic conditions. We used a 12-yr record in the Hudson River to explore the relationship between phytoplankton composition and zebra mussel filtration. During this period (1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005), the mean July-September filtration rate of the zebra mussel (ZMF) varied by 8-fold, and the mean biovolume of cyanobacteria, which was dominated by Microcystis, varied from 0 to 4.2 mm 3 l 21 and comprised up to 52% of total phytoplankton biovolume. There was a tendency for high cyanobacterial biomass to be associated with low rather than high ZMF. Neither the absolute nor the relative amounts of either total cyanobacteria or Microcystis were significantly correlated to ZMF alone or in combination with total phosphorus or any other physical or chemical parameters that we measured. Cyanobacterial dominance and abundance were both strongly correlated to temperature, and over 80% of the among year variance in cyanobacterial dominance could be explained by temperature in a linear model. Temperature in combination with dissolved SiO 3 explained 90% of the variation in cyanobacterial dominance. At higher temperatures and lower dissolved SiO 3 , cyanobacterial abundance increased at the expense of diatoms that dominated at lower temperatures and in higher SiO 3 years. The high explanatory value of temperature is surprising as the variation in temperature among years was relatively low (24.0-26.8uC). The results suggest that even slightly increased temperatures could lead to higher biomass and dominance of cyanobacteria in some aquatic systems.