The inverted trophic cascade in tropical plankton communities: impacts of exotic fish in the Middle Rio Doce lake district, Minas Gerais, Brazil

The present study deals with the ecological impacts of the introduction of two alien species of piscivorous fish in several lakes of the Middle Rio Doce lake district in Minas Gerais, Brazil. It was demonstrated that these effects were not restricted only to the fish community. The introduction of the predatory red piranha Pygocentrus nattereri and the tucunaré Cichla cf. ocellaris caused not only a sharp decrease in the number of native fish species, but also major shifts in other trophic levels. Just after the fish were introduced, most lakes began to show conspicuous changes in phytoplankton species composition, in which Cyanophyceae gradually came to dominate. The zooplankton community lost several species, and in some cases, such as Lake Carioca, all the cladoceran species disappeared. On the other hand, invertebrate predators, represented by the dipteran Chaoboridae, boomed in the lake, with higher densities of exotic species, probably as a result of the "ecological release" by reduction of the original fish fauna. There was a general trend of species loss in different trophic levels. All these changes are apparently associated with decreases in water quality. The present situation in these lakes demands new approaches to the management and conservation of these ecosystems.

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Changes in the crustacean communities of Lakes Michigan, Huron, and Erie following the invasion of the predatory cladoceran Bythotrephes longimanus

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f04-149 ◽

2004 ◽

Vol 61 (11) ◽

pp. 2111-2125 ◽

Cited By ~ 105

Author(s):

Richard P Barbiero ◽

Marc L Tuchman

Keyword(s):

Zooplankton Community ◽

Crustacean Zooplankton ◽

Bythotrephes Longimanus ◽

Zooplankton Community Structure ◽

Cladoceran Species ◽

Invertebrate Predators ◽

Predatory Cladoceran ◽

Leptodora Kindti ◽

Escape Responses ◽

Zooplankton Communities

The crustacean zooplankton communities in Lakes Michigan and Huron and the central and eastern basins of Lake Erie have shown substantial, persistent changes since the invasion of the predatory cladoceran Bythotrephes in the mid-1980s. A number of cladoceran species have declined dramatically since the invasion, including Eubosmina coregoni, Holopedium gibberum, Daphnia retrocurva, Daphnia pulicaria, and Leptodora kindti, and overall species richness has decreased as a result. Copepods have been relatively unaffected, with the notable exception of Meso cyclops edax, which has virtually disappeared from the lakes. These species shifts have for the most part been consistent and equally pronounced across all three lakes. Responses of crustacean species to the Bythotrephes invasion do not appear to be solely a consequence of size, and it is likely that other factors, e.g., morphology, vertical distribution, or escape responses, are important determinants of vulnerability to predation. Our results indicate that invertebrate predators in general, and invasive ones in particular, can have pronounced, lasting effects on zooplankton community structure.

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Structure and biodiversity of zooplankton communities in freshwater habitats of a Vereda Wetland Region, Minas Gerais, Brazil

Acta Limnologica Brasiliensia ◽

10.1590/s2179-975x0415 ◽

2015 ◽

Vol 27 (3) ◽

pp. 275-288 ◽

Cited By ~ 4

Author(s):

Olívia Penatti Pinese ◽

José Fernando Pinese ◽

Kleber Del Claro

Keyword(s):

Aquatic Macrophytes ◽

Biological Diversity ◽

Zooplankton Community ◽

Environmental Parameters ◽

Minas Gerais ◽

Southeastern Brazil ◽

Brazilian Savannah ◽

Local Diversity ◽

Freshwater Habitats ◽

The Difference

Abstract Aims: Vereda wetlands are among the most important aquatic habitats in Brazilian savannah (Cerrado) because of their association with river springs and its relevancy for biodiversity conservation. This study aimed to determine and compare the biodiversity of zooplankton in vereda lakes, differentiated by the presence or absence of aquatic macrophytes at an environmental reserve in Uberlândia, Minas Geais, Southeastern Brazil. Zooplanctonic abundance patterns and their relation with environmental parameters were also discussed and presented through multivariate statistics. Methods Twelve samples were taken at water surface, at 15-day intervals in 2006. It was observed a total richness of 75 species, including 12 genera, 29 species and one sub-species as new records for Minas Gerais State. Results Rotifers were the predominant group and Lecanidae was the most diverse family. Among cladocerans, Chydoridae showed the greatest richness and Bosminidae the highest abundance. Few adult copepods were sampled in this study, but nauplii were very frequent. Cyclopidae was the most common family among copepods and there was no record of Calanoida. Conclusions The difference in composition among the studied lakes was remarkable. The lake with macrophytes showed the greatest richness but the lowest density, and the opposite situation occurred in the other lake. This can be explained by the fact that aquatic macrophytes, as primary producers, exert a bottom-up effect on zooplankton community, sustaining a high local diversity in contrast with a low numeric abundance of these microorganisms. Therefore, this pattern may have been created by the surround heterogeneity and, at the same time, by the reduction of available minerals of the system caused by macrophyte matter fixation. Many studies on zooplankton need to be developed in palm swamp communities in order to better comprehend the biological diversity and the energy balance in different habitats for the conservation of aquatic ecosystems.

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Metabarcoding reveals different zooplankton communities in northern and southern areas of the North Sea

10.1101/2020.07.23.218479 ◽

2020 ◽

Author(s):

Jan Niklas Macher ◽

Berry B. van der Hoorn ◽

Katja T. C. A. Peijnenburg ◽

Lodewijk van Walraven ◽

Willem Renema

Keyword(s):

North Sea ◽

Zooplankton Community ◽

Taxonomic Diversity ◽

Molecular Techniques ◽

Trophic Levels ◽

List Type ◽

The North ◽

Shelf Sea ◽

The North Sea ◽

Zooplankton Communities

AbstractZooplankton are key players in marine ecosystems, linking primary production to higher trophic levels. The high abundance and high taxonomic diversity renders zooplankton ideal for biodiversity monitoring. However, taxonomic identification of the zooplankton assemblage is challenging due to its high diversity, subtle morphological differences and the presence of many meroplanktonic species, especially in coastal seas. Molecular techniques such as metabarcoding can help with rapid processing and identification of taxa in complex samples, and are therefore promising tools for identifying zooplankton communities. In this study, we applied metabarcoding of the mitochondrial cytochrome c oxidase I gene to zooplankton samples collected along a latitudinal transect in the North Sea, a shelf sea of the Atlantic Ocean. Northern regions of the North Sea are influenced by inflow of oceanic Atlantic waters, whereas the southern parts are characterised by more coastal waters. Our metabarcoding results indicated strong differences in zooplankton community composition between northern and southern areas of the North Sea, particularly in the classes Copepoda, Actinopterygii (ray-finned fishes) and Polychaeta. We compared these results to the known distributions of species reported in previous studies, and by comparing the abundance of copepods to data obtained from the Continuous Plankton Recorder (CPR). We found that our metabarcoding results are mostly congruent with the reported distribution and abundance patterns of zooplankton species in the North Sea. Our results highlight the power of metabarcoding to rapidly assess complex zooplankton samples, and we suggest that the technique could be used in future monitoring campaigns and biodiversity assessments.HighlightsZooplankton communities are different in northern and southern areas of the North SeaMetabarcoding results are consistent with known species distributions and abundanceMetabarcoding allows for fast identification of meroplanktonic species

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Copepods act as omnivores in a (sub)tropical reservoir: Implication for the top-down effect on phytoplankton

Journal of Limnology ◽

10.4081/jlimnol.2018.1748 ◽

2018 ◽

Vol 77 (2) ◽

Cited By ~ 1

Author(s):

Qiuqi Lin ◽

Liang Peng ◽

Yang Yang ◽

Bo-Ping Han

Keyword(s):

Organic Matter ◽

Trophic Position ◽

Zooplankton Community ◽

Nitrogen Isotope ◽

Terrestrial Organic Matter ◽

Tropical Reservoir ◽

Cascading Effect ◽

Cladoceran Species ◽

Grazing Effect ◽

One Year

Tropical reservoirs in China receive a high input of organic matter from surrounding watersheds and this represents a significant resource for zooplankton consumers. Copepods are often the dominant zooplankton group in the tropical systems. Whether copepods tend to be omnivorous and their potential cascading effect on phytoplankton are subjects of debate. We used stable carbon and nitrogen isotope analyses to elucidate the allochthony and trophic positions of two copepod species (Phyllodiaptomus tunguidus and Mesocyclops thermocyclopoides) and one cladoceran species (Diaphanosoma orghidani) over a one-year period in a tropical oligo-mesotrophic reservoir in China. We assumed the filter-feeding D. orghidani was herbivorous and we used it as a baseline indicator of δ15N to estimate the trophic position of the two copepods. P. tunguidus and M. thermocyclopoides had an average trophic level that was 0.7 and 0.5 higher, respectively, than that of D. orghidani. M. thermocyclopoides showed seasonal differences in trophic position and an increase in trophic position with rising temperatures, whereas P. tunguidus remained omnivorous throughout the year. All three zooplankton species had a much higher degree of allochthony in the flood season than in the dry season, and their allochthony was positively related to the allochthony of the particulate organic matter input. The two copepods’ omnivorous behavior suggests their allochthony was primarily linked to microbial food web based on the input of terrestrial organic matter. The chlorophyll a to total phosphorus ratio was much higher when P. tunguidus dominated the zooplankton community than when D. orghidani dominated. The ratio was positively related to the ratio of omnivorous adult copepods to cladoceran biomass but not to the zooplankton:phytoplankton biomass ratio. Our results suggest that copepods tended to be omnivorous and relied heavily on allochthonous material in the study reservoir. The indirect cascading effect is likely to be stronger than the direct grazing effect, resulting in a positive effect of copepods on the phytoplankton.

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Effects of Consecutive Extreme Weather Events on a Temperate Dystrophic Lake: A Detailed Insight into Physical, Chemical and Biological Responses

Water ◽

10.3390/w12051411 ◽

2020 ◽

Vol 12 (5) ◽

pp. 1411 ◽

Cited By ~ 2

Author(s):

Maria Calderó-Pascual ◽

Elvira de Eyto ◽

Eleanor Jennings ◽

Mary Dillane ◽

Mikkel René Andersen ◽

...

Keyword(s):

Global Climate ◽

Zooplankton Community ◽

Fold Increase ◽

Extreme Weather ◽

Zooplankton Biomass ◽

Trophic Levels ◽

Extreme Weather Events ◽

Weather Events ◽

Fold Reduction ◽

Stable Conditions

Between May and July 2018, Ireland experienced an exceptional heat wave, which broke long-term temperature and drought records. These calm, stable conditions were abruptly interrupted by a second extreme weather event, Atlantic Storm Hector, in late June. Using high-frequency monitoring data, coupled with fortnightly biological sampling, we show that the storm directly affected the stratification pattern of Lough Feeagh, resulting in an intense mixing event. The lake restabilised quickly after the storm as the heatwave continued. During the storm there was a three-fold reduction in Schmidt stability, with a mixed layer deepening of 9.5 m coinciding with a two-fold reduction in chlorophyll a but a three-fold increase in total zooplankton biomass. Epilimnetic respiration increased and net ecosystem productivity decreased. The ratio of total nitrogen:total phosphorus from in-lake versus inflow rivers was decoupled, leading to a cascade effect on higher trophic levels. A step change in nitrogen:phosphorus imbalances suggested that the zooplankton community shifted from phosphorus to nitrogen nutrient constraints. Such characterisations of both lake thermal and ecological responses to extreme weather events are relatively rare but are crucial to our understanding of how lakes are changing as the impacts of global climate change accelerate.

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Short-scale temporal variability of physical, biological and biogeochemical processes in the NW Mediterranean Sea: an introduction

Biogeosciences ◽

10.5194/bg-6-453-2009 ◽

2009 ◽

Vol 6 (3) ◽

pp. 453-461 ◽

Cited By ~ 16

Author(s):

V. Andersen ◽

M. Goutx ◽

L. Prieur ◽

J. R. Dolan

Keyword(s):

Mediterranean Sea ◽

Temporal Variability ◽

Time Course ◽

Special Section ◽

Zooplankton Community ◽

Western Mediterranean ◽

Trophic Levels ◽

Data Set ◽

Nw Mediterranean ◽

Nw Mediterranean Sea

Abstract. In the framework of the PROOF-PECHE project (http://www.obs-vlfr.fr/proof/vt/op/ec/peche/pec.htm) a multi-disciplinary team performed experiments and collected samples during the DYNAPROC 2 cruise aboard the RV Thalassa from September to October in 2004. The cruise provided data on the functioning of the pelagic food web by sampling over a month long period in the NW Mediterranean Sea at a fixed station subject to weak horizontal advection currents during a period of hydrological stability. This paper describes the background of the cruise and provides an overview of the results derived from the campaign which constitute the special section. The major objective of the cruise was to assess the relative importance and variability of the pathways of carbon in the open ocean. Intensive sampling through 4 periods of 5 days each was accomplished at a site near the DYFAMED time-series site. The site was near stable in terms of hydrodynamics as there was some evidence of an intrusion of low-salinity coastal water. The cruise yielded a comprehensive data set acquired by sampling over a vertical spatial dimension (0–1000 m) and at high frequencies (ranging from every 3, 6, 12 and/or 24 h), unique for the summer to autumn transition in the North Western Mediterranean. Parameters investigated included the biochemical composition of dissolved organic matter (lipids), and the structure of bacterial communities, phytoplankton and zooplankton community compositions and abundances, as well as zooplankton metabolism, and particulate organic carbon fluxes. Nearly all the parameters described in this section, as well as reports appearing elsewhere, showed time-course variabilities of similar magnitude to those known from a previous study of the spring-summer seasonal transition, a period of marked hydrological change, at the same study site. Remarkably, the least variable characteristic of the system appeared to be the identities of the dominant taxa across several trophic levels (copepods, phytoplankton, ciliates, and bacteria) throughout the study period despite large shifts in stock sizes and fluxes. Thus, the studies of DYNAPROC 2 documented considerable temporal variability of stocks and rates in a system which was, from a hydrological and taxonomic point of view, relatively stable.

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A cascade of evolutionary change alters consumer-resource dynamics and ecosystem function

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2012.0496 ◽

2012 ◽

Vol 279 (1741) ◽

pp. 3184-3192 ◽

Cited By ~ 60

Author(s):

Matthew R. Walsh ◽

John P. DeLong ◽

Torrance C. Hanley ◽

David M. Post

Keyword(s):

Life History ◽

Ecosystem Function ◽

Life History Evolution ◽

Evolutionary Change ◽

Ecological Impacts ◽

Trophic Levels ◽

Natural Setting ◽

Resource Dynamics ◽

History Evolution ◽

Consumer Resource

It is becoming increasingly clear that intraspecific evolutionary divergence influences the properties of populations, communities and ecosystems. The different ecological impacts of phenotypes and genotypes may alter selection on many species and promote a cascade of ecological and evolutionary change throughout the food web. Theory predicts that evolutionary interactions across trophic levels may contribute to hypothesized feedbacks between ecology and evolution. However, the importance of ‘cascading evolutionary change’ in a natural setting is unknown. In lakes in Connecticut, USA, variation in migratory behaviour and feeding morphology of a fish predator, the alewife ( Alosa pseudoharengus ), drives life-history evolution in a species of zooplankton prey ( Daphnia ambigua ). Here we evaluated the reciprocal impacts of Daphnia evolution on ecological processes in laboratory mesocosms. We show that life-history evolution in Daphnia facilitates divergence in rates of population growth, which in turn significantly alters consumer-resource dynamics and ecosystem function. These experimental results parallel trends observed in lakes. Such results argue that a cascade of evolutionary change, which has occurred over contemporary timescales, alters community and ecosystem processes.

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Freshwater discharges drive high levels of methylmercury in Arctic marine biota

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1505541112 ◽

2015 ◽

Vol 112 (38) ◽

pp. 11789-11794 ◽

Cited By ~ 66

Author(s):

Amina T. Schartup ◽

Prentiss H. Balcom ◽

Anne L. Soerensen ◽

Kathleen J. Gosnell ◽

Ryan S. D. Calder ◽

...

Keyword(s):

Water Column ◽

Marine Mammals ◽

River Mouth ◽

Ecological Impacts ◽

Trophic Levels ◽

Indigenous Populations ◽

Marine Biota ◽

Terrestrial Organic Matter ◽

Water Column Stratification ◽

Freshwater Inputs

Elevated levels of neurotoxic methylmercury in Arctic food-webs pose health risks for indigenous populations that consume large quantities of marine mammals and fish. Estuaries provide critical hunting and fishing territory for these populations, and, until recently, benthic sediment was thought to be the main methylmercury source for coastal fish. New hydroelectric developments are being proposed in many northern ecosystems, and the ecological impacts of this industry relative to accelerating climate changes are poorly characterized. Here we evaluate the competing impacts of climate-driven changes in northern ecosystems and reservoir flooding on methylmercury production and bioaccumulation through a case study of a stratified sub-Arctic estuarine fjord in Labrador, Canada. Methylmercury bioaccumulation in zooplankton is higher than in midlatitude ecosystems. Direct measurements and modeling show that currently the largest methylmercury source is production in oxic surface seawater. Water-column methylation is highest in stratified surface waters near the river mouth because of the stimulating effects of terrestrial organic matter on methylating microbes. We attribute enhanced biomagnification in plankton to a thin layer of marine snow widely observed in stratified systems that concentrates microbial methylation and multiple trophic levels of zooplankton in a vertically restricted zone. Large freshwater inputs and the extensive Arctic Ocean continental shelf mean these processes are likely widespread and will be enhanced by future increases in water-column stratification, exacerbating high biological methylmercury concentrations. Soil flooding experiments indicate that near-term changes expected from reservoir creation will increase methylmercury inputs to the estuary by 25–200%, overwhelming climate-driven changes over the next decade.

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Golden Shiner (Notemigonus crysoleucas) Population Abundance Correlations with Food and Predators

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f89-101 ◽

1989 ◽

Vol 46 (5) ◽

pp. 810-817 ◽

Cited By ~ 14

Author(s):

Mark R. S. Johannes ◽

Donald J. McQueen ◽

Tom J. Stewart ◽

John R. Post

Keyword(s):

Zooplankton Community ◽

Zooplankton Abundance ◽

Predator Density ◽

Data Set ◽

Zooplankton Community Structure ◽

Piscivorous Fish ◽

Golden Shiner ◽

Stock Recruitment ◽

Young Of The Year ◽

Notemigonus Crysoleucas

A winterkill at Lake St. George, Ontario eliminated most of the piscivorous fish and some of the planktivores and also influenced zooplankton community structure. This disturbance and the subsequent recovery of the populations provided the opportunity to evaluate potential impacts of food and predators on the population structure and abundance of the dominant planktivore; the golden shiner (Notemigonus crysoleucas). interpretation of the 8-yr data set suggested that there was a positive relationship between adult golden shiner condition and zooplankton abundance, but that this did not translate into a significant stock–recruitment relationship between female numbers and young-of-the-year (YOY) recruitment. Also, there was no significant relationship between golden shiner survival and zooplankton abundance. However, there were significant negative correlations between YOY and adult golden shiner survival estimates and predator abundances. We conclude that at Lake St. George, golden shiner recruitment and population density is strongly influenced by predator density and is not influenced by food abundance.

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Meso- and macro-zooplankton community structure of the Amundsen Sea Polynya, Antarctica (Summer 2010–2011)

Elem Sci Anth ◽

10.12952/journal.elementa.000033 ◽

2015 ◽

Vol 3 ◽

Cited By ~ 10

Author(s):

Stephanie E. Wilson ◽

Rasmus Swalethorp ◽

Sanne Kjellerup ◽

Megan A. Wolverton ◽

Hugh W. Ducklow ◽

...

Keyword(s):

Community Structure ◽

Trophic Position ◽

Mixed Layer Depth ◽

Zooplankton Community ◽

Thick Layer ◽

Trophic Levels ◽

Zooplankton Abundance ◽

Amundsen Sea ◽

Zooplankton Community Structure ◽

Pigment Ratios

Abstract The Amundsen Sea Polynya (ASP) has, on average, the highest productivity per unit area in Antarctic waters. To investigate community structure and the role that zooplankton may play in utilizing this productivity, animals were collected at six stations inside and outside the ASP using paired “day-night” tows with a 1 m2 MOCNESS. Stations were selected according to productivity based on satellite imagery, distance from the ice edge, and depth of the water column. Depths sampled were stratified from the surface to ∼ 50–100 m above the seafloor. Macrozooplankton were also collected at four stations located in different parts of the ASP using a 2 m2 Metro Net for krill surface trawls (0–120 m). The most abundant groups of zooplankton were copepods, ostracods, and euphausiids. Zooplankton biovolume (0.001 to 1.22 ml m-3) and abundance (0.21 to 97.5 individuals m-3) varied throughout all depth levels, with a midsurface maximum trend at ∼ 60–100 m. A segregation of increasing zooplankton trophic position with depth was observed in the MOCNESS tows. In general, zooplankton abundance was low above the mixed layer depth, a result attributed to a thick layer of the unpalatable colonial haptophyte, Phaeocystis antarctica. Abundances of the ice krill, Euphausia crystallarophias, however, were highest near the edge of the ice sheet within the ASP and larvae:adult ratios correlated with temperature above a depth of 60 m. Total zooplankton abundance correlated positively with chlorophyll a above 150 m, but negative correlations observed for biovolume vs. the proportion of P. antarctica in the phytoplankton estimated from pigment ratios (19’hexanoyloxyfucoxanthin:fucoxanthin) again pointed to avoidance of P. antarctica. Quantifying zooplankton community structure, abundance, and biovolume (biomass) in this highly productive polynya helps shed light on how carbon may be transferred to higher trophic levels and to depth in a region undergoing rapid warming.

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