Effects Of Zebra Mussels Research Articles

Increased mercury concentrations in walleye and yellow perch in lakes invaded by zebra mussels.

Zebra mussels (Dreissena polymorpha) are invasive species that alter ecosystems and food webs with the potential to affect aquatic mercury cycling and bioaccumulation in fishes, although the effect of zebra mussels on fish tissue mercury has not been tested in inland lakes. We assessed differences in fish tissue mercury concentrations and food webs in Minnesota lakes with and without zebra mussels while controlling for other lake and watershed characteristics. Mercury concentrations in adult walleye (Sander vitreus) and yellow perch (Perca flavescens) were 72 % and 157 % higher, respectively, in lakes containing zebra mussels compared to uninvaded lakes. Mercury in young of year (age-0) fish was also elevated, with mercury concentrations 97 % and 82 % higher in age-0 walleye and yellow perch, respectively, in zebra mussel lakes. Walleye mercury concentrations exceeded 0.22 ppm - a threshold triggering more restrictive human consumption advisories for sensitive populations - at a 23 % smaller size, and average-sized walleye (420 mm) exceeded this threshold at a rate of 77 % in invaded lakes, compared to 35 % in uninvaded lakes. Walleye and yellow perch relied more on littoral resources in lakes with zebra mussels but did not feed at meaningfully higher trophic levels. Increased fish tissue mercury in lakes invaded by zebra mussels have consequential implications for fisheries and human health.

Comment: Novak et al. (2021) overestimated the successes of species translocations and minimized their risks

Comment: Novak et al. (2021) overestimated the successes of species translocations and minimized their risks

Walleye growth declines following zebra mussel and Bythotrephes invasion

Invasive species represent a threat to aquatic ecosystems globally; however, impacts can be heterogenous across systems. Documented impacts of invasive zebra mussels (Dreissena polymorpha) and spiny water fleas (Bythotrephes cederströmii; hereafter Bythotrephes) on native fishes are variable and context dependent across locations and time periods. Here, we use a hierarchical Bayesian analysis of a 35-year dataset on two fish species from 9 lakes to demonstrate that early life growth of ecologically important fishes are influenced by these aquatic invasive species. Walleye (Sander vitreus) in their first year of life grew more slowly in the presence of either invader after correcting for temperature (measured by degree days), and were on average 12 or 14% smaller at the end of their first summer following invasion by Bythotrephes or zebra mussels, respectively. Yellow perch (Perca flavescens) growth was less affected by invasion. Yellow perch on average grew more slowly in their first year of life following invasion by zebra mussels, although this effect was not statistically distinguishable from zero. Early life growth of both walleye and yellow perch was less tightly coupled to degree days in invaded systems, as demonstrated by increased variance surrounding the degree day-length relationship. Smaller first-year size is related to walleye survival and recruitment to later life stages and has important implications for lake food webs and fisheries management. Future research quantifying effects of zebra mussels and Bythotrephes on other population-level processes and across a wider gradient of lake types is needed to understand the mechanisms driving observed changes in walleye growth.

Effects of zebra mussels (Dreissena polymorpha) on phytoplankton community structure under eutrophic conditions

Effects of zebra mussels (Dreissena polymorpha) on phytoplankton community structure under eutrophic conditions

Lake Characteristics, Population Properties and Invasion History Determine Impact of Invasive Bivalves on Lake Nutrient Dynamics

Invasive species can have large impacts on ecosystems, including the cycling and distribution of nutrients. To determine the whole-ecosystem effects of invasive zebra mussels on lake nutrient dynamics, we sampled 10 invaded Minnesota lakes spanning a broad trophic status gradient. We conducted N and P excretion and biodeposition rate measurements and determined the C, N and P composition of dreissenid soft tissues and shell material in the study lakes. We also estimated the whole-lake biomass of live dreissenid mussels and their dead shell material, constructing comprehensive nutrient budgets for dreissenid populations in the study lakes. We used the results of our measurements and published data to estimate the contribution of dreissenids to P budgets in 24 additional lakes in Europe and North America. Results show that nutrient cycling rates and composition of soft tissues and shells vary with mussel size and lake trophic status. Zebra mussels made variable, but often large, contributions to cycling and storage of water column standing stocks of POC, PON and TP in the study and literature lakes. In some lakes, the effects of zebra mussels on P dynamics were also considerable in the context of estimated P external and internal loading, sediment sequestration and effects of other biota. We show that the impact of zebra mussels on whole-lake nutrient budgets depends on lake properties, dreissenid population characteristics and invasion history. This information can be used by ecosystem managers to prioritize invasion prevention efforts toward lakes likely to be most strongly impacted by zebra mussel invasions.

Effects of zebra mussels on cladoceran communities under eutrophic conditions

The purpose of this study was to determine how zebra mussels affected cladoceran community structure under eutrophic conditions. We conducted a mesocosm study where we manipulated the presence of zebra mussels and the presence of large-bodied Daphnia (Daphnia magna and Daphnia pulicaria). We also conducted a complimentary life-table experiment to determine how water from the zebra mussel treatment affected the life history characteristics of the cladoceran species. We anticipated that small- and large-bodied cladoceran species would respond differently to changes in algal quality and quantity under the effects of zebra mussels. Large-bodied Daphnia successfully established in the zebra mussel treatment but failed to grow in the control. We did not observe positive relationships between food concentrations and cladoceran abundances. However, the phosphorus content in the seston indicated that food quality was below the threshold level for large-bodied cladocerans at the beginning of the experiment. We believe that zebra mussels quickly enhanced the phosphorus content in the seston due to the excretion of inorganic phosphorus, thus facilitating the development of large-bodied Daphnia. In conclusion, our results suggest that zebra mussels can alter the phosphorus content of seston in lakes and this can affect the dynamics of crustacean zooplankton.

Regional Dispersal Influences Zooplankton Community Response to Dreissena polymopha Invasion

Aquatic systems are becoming increasingly susceptible to invasive species whereby local species are reduced in abundance and richness leading to changes in many food webs. Dispersal of species from surrounding lakes may provide a natural mechanism to increase local resistance by providing a diversity of locally adapted species to colonize affected communities. This study examined how zooplankton dispersal could potentially reduce the effects of the invasive zebra mussel, Dreissena polymorpha, on zooplankton community total abundance, species richness and diversity. Field experiments were conducted in 20 large tanks, with five replicates, to observe zooplankton community response to (1) the presence and absence of zebra mussels, and (2) the presence and absence of regional disperser zooplankton. Live regional zooplankton, from six surrounding lakes, were added fortnightly to dispersal treatments, while heat-killed zooplankton were added to no-dispersal treatments. All tanks were sampled for chlorophyll and zooplankton community samples prior to dispersal additions. Zooplankton were counted and identified as cladocerans and copepods (macrozooplankton), and rotifers (microzooplankton) to species. In the presence of mussels, chlorophyll was significantly depleted, reducing nutrient availability. All zooplankton richness and abundance decreased suggesting strong resource competition and direct predation by mussels. Dispersal did not affect macrozooplankton community structure, however, dispersal influenced the effect of zebra mussels on rotifers, further decreasing richness. This suggests species from the surrounding lakes may be highly competitive among local species, further proposing that regional species may influence zooplankton community structure and responses to zebra mussel invasion, but the effect is species dependent.

Filtration effects of zebra mussels on pathogens and total bacterial burden in the Odra Lagoon (South Baltic).

As a result of their mode of filter feeding, zebra mussels (Dreissena polymorpha Pall.) have been observed to purify natural water bodies and in vitro. Therefore, the possibility of using zebra mussels for water purification was investigated in a slightly brackish water body of a large lagoon. In this study, water samples were taken above, near and at distance from zebra mussel beds (MB) in the Odra Lagoon in North East Germany. Near typical bacterial species like Aeromonas spp. pathogenic bacteria with potential relation to hospital wastewater pollution (Burkholderia cepacia, Staphylococcus aureus, Weeksella spp.) were detected. There were no correlations found between either total bacteria or pathogens and distance to MB and no antimicrobial effect of the mussels could be deduced. For bioremediation in larger water bodies like lagoons, natural zebra MB do not seem to play a major antimicrobial role and the effect of artificial mussel grids especially against hospital pathogens should be investigated.

Dispersal acts as both bane and balm for invaded zooplankton communities

Dispersal of native species from the regional pool can recover invaded communities to a pre-invaded state by supplementing declining populations or providing resistant species. However, dispersal may also exacerbate the negative effects of an invader. Introduced species can open or create new niche space, which could facilitate the establishment of competitors or predators that previously could not succeed in the uninvaded local community. To investigate the interaction between dispersal and invasion by a non-native consumer, we conducted a field mesocosm experiment that introduced zebra mussels into native zooplankton communities. Regional zooplankton were collected and added to both invaded and uninvaded communities. In uninvaded communities, zooplankton dispersal reduced cladoceran diversity by 40%, rotifer abundance by 65% and copepod nauplii abundance by 80%. In invaded communities, dispersal increased cladoceran diversity by 60%, but also further exacerbated the negative effects of zebra mussels on rotifer abundance. This experiment illustrates the potential for dispersal to both positively and negatively affect local communities, and how these effects may change with disturbance and the taxa or community metric of study.

Effects of invasive zebra mussels on phytoplankton, turbidity, and dissolved nutrients in reservoirs

Few experiments have quantified the effects of invasive zebra mussels (Dreissena polymorpha) on man-made reservoirs relative to other aquatic habitats. Reservoirs, however, are the dominate water body type in many of the states that are at the current front of the zebra mussel invasion into the western United States. The objective of this research, therefore, was to determine how zebra mussels affected phytoplankton, turbidity, and dissolved nutrients in water that was collected from three Kansas reservoirs that varied in trophic state (mesotrophic to hypereutrophic), but all experienced frequent cyanobacterial blooms. Laboratory mesocosm experiments were conducted to document the effects of zebra mussels on cyanobacteria and general water quality characteristics in the reservoir water. Zebra mussels significantly reduced algal biomass, and the total biovolume of cyanobacteria (communities were dominated by Anabaena) in each reservoir experiment. The effects of zebra mussels on other major algal groups (diatoms, flagellates, and green algae) and algal diversity were less consistent and varied between the three reservoir experiments. Similarly, the effects of zebra mussels on nutrient concentrations varied between experiments. Zebra mussels increased dissolved phosphorus concentrations in two of the reservoir experiments, but there was no effect of zebra mussels on dissolved phosphorus in the mesotrophic reservoir experiment. Combined, our results strongly suggest that zebra mussels have the potential to significantly impact reservoirs as they continue to expand throughout the western United States. Moreover, the magnitude of these effects may be context dependent and vary depending on the trophic state and/or resident phytoplankton communities of individual reservoirs as has similarly been reported for natural lakes.

Mussel grazing and the importance of hydrodynamic coupling: reply

Conroy is correct to note that our experimental study did not take into account how hydrodynamic coupling affected the ability of zebra mussels to graze algae. Unfortunately, the size of our mesocosms (18 L) did not allow for, nor were they designed to provide, a thorough quantification of benthic–pelagic coupling. Therefore, we agree with Conroy that the magnitude of zebra mussel effects on phytoplankton within individual systems will depend on site-specific factors such as turbulent mixing, mussel filtering efficiency, phytoplankton reproduction and sinking rates, and nutrient remineralization. As such, we made no attempts to directly quantify zebra mussel filtration or grazing rates in our study reservoir. Instead, we presented our research as “a preliminary study” and suggest that additional research is needed to address among other things “ . . . how zebra mussels affect algal responses to nutrient enrichment in experiments that better mimic natural conditions (e.g. large in situ reservoir enclosures).” With that said, however, we do not agree with Conroy when he states that our proposal is inconsistent with published examples of post-invasion increases in phytoplankton, benthic algae and cyanobacterial toxins. For example, he provides two references (Raikow et al., 2004; Conroy et al., 2005) to show that phytoplankton have increased following invasion. However, as cited in our original manuscript, there are also numerous examples of phytoplankton decreasing following invasion; even Raikow et al. (Raikow et al., 2004) reported that lakes with zebra mussels had lower water column concentrations of total phytoplankton biomass than lakes without zebra mussels. Furthermore, zebra mussels can “decouple” relationships between total phosphorus (TP) and chlorophyll a so that observed yields of algal biomass are less than predicted from TP concentrations (see Nichols et al., 2001 and other references cited in Dzialowski and Jessie, 2009). It is also important to note that we address how zebra mussels may impact both benthic algae (e.g. they may increase) and cyanobacteria (e.g. the effects may be nutrient dependent) in eutrophic reservoirs in light of recently published research [see Dzialowski and Jessie, 2009 for more details]. Combined, we believe that these studies are consistent with our predictions that “ . . . invaded reservoirs may exhibit lower yields of algal biomass than those predicted from TP concentrations . . . ” and that “ . . . the severity of algal bloom events may be lower in invaded reservoirs if zebra mussels are able to directly negate or mask the increasing effects of external nutrient pulses on algal biomass as we have shown here.” We would also like to respond to Conroy’s assertion that the effects of zebra mussels on phytoplankton are most apparent in the 1 m boundary layer at the bottom of lakes. While this appears to be true for the western basin of Lake Erie, it is also important to note that zebra mussels have reduced phytoplankton biomass in the epilimnion of stratified lakes and reservoirs as well (Yu and Culver, 2000; Raikow et al., 2004; Knoll et al., 2008). Therefore, it seems inappropriate to suggest that the effects of zebra mussels on phytoplankton will be restricted mainly to the benthos. As such, additional research is needed to determine how hydrodynamic coupling affects the ability of zebra mussels to impact systems other than the Great Lakes including reservoirs of the Central Plains which often have both highly mixed (e.g. riverine zone) and thermally stratified (e.g. lacustrine zone) regions.

Invasive species impacts on ecosystem structure and function: A comparison of the Bay of Quinte, Canada, and Oneida Lake, USA, before and after zebra mussel invasion

As invasion rates of exotic species increase, an ecosystem level understanding of their impacts is imperative for predicting future spread and consequences. We have previously shown that network analyses are powerful tools for understanding the effects of exotic species perturbation on ecosystems. We now use the network analysis approach to compare how the same perturbation affects another ecosystem of similar trophic status. We compared food web characteristics of the Bay of Quinte, Lake Ontario (Canada), to previous research on Oneida Lake, New York (USA) before and after zebra mussel ( Dreissena polymorpha) invasion. We used ecological network analysis (ENA) to rigorously quantify ecosystem function through an analysis of direct and indirect food web transfers. We used a social network analysis method, cohesion analysis (CA), to assess ecosystem structure by organizing food web members into subgroups of strongly interacting predators and prey. Together, ENA and CA allowed us to understand how food web structure and function respond simultaneously to perturbation. In general, zebra mussel effects on the Bay of Quinte, when compared to Oneida Lake, were similar in direction, but greater in magnitude. Both systems underwent functional changes involving focused flow through a small number of taxa and increased use of benthic sources of production; additionally, both systems structurally changed with subgroup membership changing considerably (33% in Oneida Lake) or being disrupted entirely (in the Bay of Quinte). However, the response of total ecosystem activity (as measured by carbon flow) differed between both systems, with increasing activity in the Bay of Quinte, and decreasing activity in Oneida Lake. Thus, these analyses revealed parallel effects of zebra mussel invasion in ecosystems of similar trophic status, yet they also suggested that important differences may exist. As exotic species continue to disrupt the structure and function of our native ecosystems, food web network analyses will be useful for understanding their far-reaching effects.

Seasonal effects of zebra mussels on littoral nitrogen transformation rates in Gull Lake, Michigan, U.S.A.

Summary 1 Zebra mussels (Dreissena polymorpha) are successful colonisers of lake littoral habitats and they interact strongly with littoral benthos. Previous research suggests that localised areas colonised by zebra mussels may be hotspots of nitrogen (N) cycling. 2 The effects of zebra mussels on nitrification and denitrification rates were examined approximately every other month for 1 year in Gull Lake, Michigan, U.S.A. Littoral sediment was collected from an area free of zebra mussels and distributed into shallow trays; rocks colonised with zebra mussels were placed in half of the trays, while uncolonised rocks were placed in the remaining trays. After an incubation period of 6–8 weeks in the lake, sediment and zebra mussels were collected from the trays, replaced with new sediment and zebra mussels, and placed in the lake for the next interval. In the laboratory, sediment nitrification and denitrification rates were measured for each tray. 3 Sediment nitrification rates did not increase in the presence of zebra mussels; instead nitrification rates were sensitive to changes in water temperature and increased with increasing exchangeable sediment ammonium. In contrast, denitrification rates increased in sediment trays with zebra mussels in the winter when nitrate (NO3−) availability was high and when Chara did not grow in the trays. 4 Sediment denitrification was NO3−-limited in all seasons, regardless of zebra mussel treatment. However, sediment in the presence of zebra mussels responded less to NO3− addition, suggesting that NO3− limitation of denitrification can be reduced by zebra mussel activity. Zebra mussels have a seasonally variable impact on sediment denitrification rates, and this may translate into altered seasonal patterns of N cycling in localised areas of lakes where they are particularly abundant.

Effects of zebra mussels on a native amphipod and the invasiveDikerogammarus villosus: the influence of biodeposition and structural complexity

In the last decades, zebra mussels (Dreissena polymorpha) have invaded many freshwater systems with severe consequences for entire communities. Most benthic macroinvertebrates, especially amphipods and chironomids, increase in abundance in the presence of zebra mussels. Increased structural complexity and an unknown biotic factor lead to this effect. Dreissena-associated factors that might influence populations of the native Gammarus roeselii and the invader Dikerogammarus villosus in Lake Constance, Central Europe, were investigated in laboratory experiments. These factors were: 1) increased structural complexity related to mussel shells, 2) Dreissena biodeposition, 3) chironomids, the presence of which is increased by biodeposited matter, and 4) Dreissena kairomones. In habitat-choice experiments, the native and omnivorous amphipod G. roeselii showed a preference for mussel shells with biodeposited material and for mussel shells with biodeposited material with chironomids, whereas the invasive and predatory amphipod D. villosus showed a preference only for mussel shells with biodeposited material with chironomids. In a kairomone y-maze experiment, both amphipods avoided zebra-mussel-conditioned lake water. These results indicate that habitat complexity and food availability, mediated directly or indirectly through biodeposited material, are the factors by which amphipod abundances are increased in the presence of Dreissena. Thus, biodeposited material can form an important new food resource, translocated from the pelagic zone to the benthos by zebra mussel filtration, and this biodeposited material might support a new detritus-based food web in the benthos.

Simulating the effect of invasive species on native freshwater mussel communities

The dispersion of invasive species is a serious problem worldwide. In North America in particular, the introduction of the zebra mussel (Dreissena polymorpha) has caused millions of dollars in economic losses and environmental damage. This paper uses ecohydraulics modeling to analyze the effects of zebra mussels on native freshwater mussel communities (unionids) in the Upper Mississippi River (UMR), USA. The model takes into account environmental forcing functions and individual mussel interactions in the form of food competition. First, hydrodynamic transport of incoming zebra mussel larvae was simulated to assess their colonization patterns on unionids. Next, population growth at various food availabilities was computed. Simulated zebra mussel densities were within the range observed in published studies and survival rates of unionids coincided with reported values for an upstream reach of the UMR. These results suggest that these two families of species may coexiste in the UMR, although the sharp decline in the unionid populations may eventually result in extirpation due to unsuccessful egg fertilization. This model provides the means for better understanding the interaction between native and invasive freshwater mussel species and it may be a valuable tool supporting the development of appropriate conservation strategies for unionids.

Effects of Zebra Mussels (Dreissena Polymorpha) on Mobility of Three Native Mollusk Species

ABSTRACT As invaders to North America, zebra mussels (Dreissena polymorpha) have contributed to the decline of benthic species, the mechanisms of which are poorly understood. In this study, we examined effects of D. polymorpha biofouling on locomotion of one pleurocerid snail (Elimia livescens) and two unionid bivalves (Ligumia nasuta and Anodonta grandis) using observational studies and removal experiments. In field and laboratory experiments, E. livescens without zebra mussels traveled 1.5–1.6 times farther than snails with zebra mussels. In field experiments, unionids without zebra mussels traveled farther and were more likely to move than unionids colonized by zebra mussels. Decreases in travel distance in the snail, but not unionids, were significantly correlated with zebra mussel loading relative to host animal mass. Limited mobility caused by zebra mussels may have consequences for gastropods and unionids by disrupting reproductive habits, predator evasion and avoidance of unbearable environmental ...

The Effects of Zebra Mussels on the Lower Planktonic Foodweb in Lake Champlain

Selective grazing by zebra mussels has altered phytoplankton communities in many North American lakes, but the specific changes are not the same in each ecosystem. Because of this variation in response, we investigated the impacts of zebra mussels on the plankton community of Lake Champlain with two objectives: first to determine whether zebra mussels increased the dominance of potentially toxic cyanobacteria in the phytoplankton, and second to explore the impact of zebra mussels on protozoans, rotifers, copepod nauplii, and other microzooplankton in the lower food web. Experiments were conducted in 200-L mesocosms filled with Lake Champlain water filtered through a 150-μm sieve to remove macrozooplankton. Zebra mussels were added to half of the mesocosms while the others were maintained as controls. Over a 96-hour experimental period, we tracked nitrogen and phosphorus concentration, chlorophyll a, microcystin concentration, and both phytoplankton and microzooplankton composition and abundance. We found an increase in SRP and total nitrogen concentration and a decrease in the ratio of TN:TP in the zebra mussel treatments over time. Microcystin was undetectable throughout the experiment using the ELISA assay. Phytoplankton biovolume, including cyanobacteria biovolume, declined significantly in the zebra mussel treatments, as did rotifer, protozoan and nauplii abundance. By both direct (consumption) and indirect (altered nutrient availabilities and increased competition) means, zebra mussels clearly seem capable of strongly influencing the lower planktonic foodweb in the many shallow water habitats of Lake Champlain.

Effects of zebra mussels (Dreissena polymorpha) on native bivalves: the beginning of the end or the end of the beginning?

AbstractThe long-term effects of an alien species may differ from transient effects that occur shortly after its invasion of a new ecosystem. Conservationists fear that the invasion of North America by the zebra mussel since 1985 may lead to the extinction of many populations and species of native bivalves. The appearance of zebra mussels in the Hudson River estuary in 1991 was followed by steep declines (65–100%) in population size of all species of native bivalves between 1992 and 1999. The body condition of all unionids and growth and recruitment of young unionids also declined significantly. Initial declines in population size and body condition were correlated primarily with the filtration rate of the zebra mussel population but not with fouling of native bivalves by zebra mussels. However, samples taken since 2000 have shown that populations of all 4 common native bivalves have stabilized or even recovered, although the zebra mussel population has not declined. The mechanisms underlying this apparen...

Zebra mussels decrease burrowing ability and growth of a native snail, Campeloma decisum

Invasive species can drive native organisms to extinction by limiting movement and accessibility to essential resources. The purpose of this study was to determine if zebra mussels (Dreissena polymorpha) affect the burrowing ability and growth rate of a native snail, Campeloma decisum. Snails with and without zebra mussels were collected from Douglas Lake, MI, and burrowing depths were studied in both the laboratory and Douglas Lake. Growth rates were calculated as the amount of shell growth from 2004 to 2005. Both the tendency of snails to burrow and the depth to which they burrowed into the substrate were significantly decreased by the presence of zebra mussels on snail shells in both laboratory and lake experiments. There was no difference in the percentage of snails that exhibited growth as a function of zebra mussel presence. However, for those snails that grew, there was a 50% higher growth rate for snails without zebra mussels compared to snails with zebra mussels. These negative effects of zebra mussels on growth and burrowing ability will likely lead to decreases in snail population densities in the future.

Negative effect of zebra mussels on foraging and habitat use by lake sturgeon (Acipenser fulvescens)

Abstract Lake sturgeon (Acipenser fulvescens) are threatened or endangered throughout much of their range. Juvenile sturgeon utilize sandy and silty habitats extensively during their growth. Invasive zebra mussels change the nature of sandy and silty habitats because they settle on and coat the habitat with the shells of living and dead individuals. The potential impacts of this increased habitat complexity on lake sturgeon is unknown. Juvenile lake sturgeon habitat choice was assessed in laboratory experiments, and zebra mussel impact on the foraging success of juvenile lake sturgeon on three different prey species was measured. Sturgeon foraging on chironomids was virtually eliminated by 95% zebra mussel cover of the sand floor of the foraging arena, and 50% cover reduced foraging significantly. Foraging on more mobile prey items (amphipods and isopods) was essentially eliminated by either 95% or 50% zebra mussel cover of the arena floor. In habitat choice experiments, sturgeon avoided the zebra‐mussel‐covered habitat more than 90% of the time. This combination of zebra mussel avoidance and reduced foraging in the presence of zebra mussels may be detrimental to sturgeon restocking programmes utilizing smaller sturgeon in zebra‐mussel‐infested waterways. Copyright © 2006 John Wiley & Sons, Ltd.