Zooplankton Community Structure in the North Sea and Northeast Atlantic: Development and Test of a Biological Model

1983 ◽  
Vol 40 (11) ◽  
pp. 1912-1924 ◽  
Author(s):  
J. Anthony Koslow

A simulation model was used to examine whether predatory interactions may regulate the size structure of marine zooplankton communities, as observed in many freshwater systems. Results of the model were consistent with the freshwater studies, such that large increases or decreases in planktivorous fish led to the dominance of small or large zooplankters, respectively. However, model predictions were not consistent with the recent decline in the northeastern Atlantic of most major elements of the pelagic zooplankton community along with North Sea herring and mackerel stocks. The overall decline of the pelagic community throughout this region indicates that zooplankton abundance may be regulated by physical forcing, and that these populations may be food- rather than predator-limited. Realistic ecological simulations of marine pelagic systems may require more complex two-layer models allowing for the effects of vertical migration, and with day–night differences in food availability and selectivity.

2020 ◽  
Author(s):  
Jan Niklas Macher ◽  
Berry B. van der Hoorn ◽  
Katja T. C. A. Peijnenburg ◽  
Lodewijk van Walraven ◽  
Willem Renema

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


1993 ◽  
Vol 27 (7-8) ◽  
pp. 353-361 ◽  
Author(s):  
B. Pinel-Alloul

Excessive concentrations of phosphorus are a common feature of hardwater eutrophic lakes in western Canada. Preliminary experimental lime treatment showed that this approach had a great potential to reduce phosphorus content and algal biomass. Therefore, two pairs of experimental and reference lakes were selected for a whole lake lime treatment and monitored for a full year prior to manipulation. This study presents the composition and size structure of the Zooplankton community of the lakes before treatment in order to assess the natural summer and inter-lake variations. Before lime treatment, seasonal means of total Zooplankton abundance and biomass ranged from 17 ± 8 to 127 ± 84 ind. L−1 and from 4 ± 2 to 138 ± 236 mg m−3, respectively. The two experimental lakes (Halftnoon and Lofty) were the richest in Zooplankton while the references lakes (Crooked and Jenkins) were the poorest. A total of 30 Zooplankton species (17 rotifers, 2 calanoids, 4 cyclopoids and 7 cladocerans) were recorded as well as 3 chaoborid species. The composition and size structure of Zooplankton varied between lakes and dates. Rotifers accounted for the majority of Zooplankton abundances (59-91%) while Cladocera (78-99%) or Copepoda (74%) in Crooked lake formed most of the Zooplankton biomass. Summer variations of the Zooplankton groups were described along with changes in size spectra. The temporal variation and the inter-lake differences in Zooplankton structure were discussed in relation to trophy, fish and invertebrate predation, and cyanophyte interactions.


Author(s):  
Johanna Pokorny

Invasive species are considered the greatest threat to aquatic ecosystem biodiversity. Bythotrephes longimanus, an exotic zooplankton species introduced to North America in the 1980s, is threatening the structure of indigenous aquatic ecosystems as it continues to invade inland Ontario lakes. As a predacious zooplankton species, B. longimanus has been shown to decrease zooplankton abundance, species richness and shift zooplankton community size structure in invaded lakes. However, much of the previous research concerning the predatory effects of B. longimanus has been on surveys of a small number of lakes or has been in controlled mesocosm or lab-based experiments. This study examines the effects of B. longimanus on the zooplankton community using size-structure characterizations (grouping individuals from the community based on size) as community measures for 311 lakes in the Muskoka Region, a highly invaded watershed in Southern Ontario. More specifically, the study explores the size-spectra of invaded versus uninvaded lakes, with reference to an array of environmental lake characteristics (water chemistry, lake morphometry,etc.), and the relevance of B. longimanus activity on the regional scale. By using such a large-scale survey we will be able to appreciate regional-scale effects, as well as encompass the multiple and more indirect trophic interactions that B. longimanus is likely having with the entire aquatic community. (Funding: NSERC & CAISN.)


1999 ◽  
Vol 56 (10) ◽  
pp. 1865-1872 ◽  
Author(s):  
Eva Wahlström ◽  
Erika Westman

In order to study density-dependent effects of invertebrate planktivory, four different densities of Bythotrephes longimanus were inoculated into mesocosm enclosures with a mixed zooplankton community. Changes in size structure and abundance of zooplankton and phytoplankton communities were recorded over a period of 3 weeks. High densities of Bythotrephes were able to reduce total zooplankton abundance, which was mainly due to a decrease in the density of the relatively large species Holopedium gibberum. The density of the smaller species Bosmina longirostris was also reduced with increasing densities of Bythotrephes, whereas rotifer abundance remained largely unaffected. The mean size of Holopedium increased with increasing densities of Bythotrephes. Despite the decrease in total zooplankton biomass in high-Bythotrephes treatments, no effect of Bythotrephes density on primary producers was observed. Our experiment shows that predacious cladocerans may reduce macrozooplankton biomass, large as well as small species. Predation from invertebrate planktivores results in a zooplankton community consisting of larger individuals. Comparing our experimental densities with densities of Bythotrephes found in natural systems suggests that invertebrate planktivores may influence size structure and abundance of zooplankton communities even in lakes with planktivorous fish.


2019 ◽  
Vol 41 (6) ◽  
pp. 803-820
Author(s):  
Emanuela Fiori ◽  
Margherita Benzi ◽  
Carla Rita Ferrari ◽  
Cristina Mazziotti

Abstract In the present study, the temporal dynamics of zooplankton community of the North West Adriatic Sea (coastal area of Emilia-Romagna region, Italy) was monitored over 12 years. The distribution and abundance of zooplankton species were investigated in relation to physical and biological parameters (temperature, salinity, dissolved oxygen and chlorophyll-a). Since November 2015 the non-indigenous copepod Pseudodiaptomus marinus, Sato, 1913 has been observed in the study area. During summer 2016, the American comb jelly Mnemiopsis leidyi, A. Agassiz, 1865 was recorded there for the first time and its presence was continuously monitored since that time (weekly observations from August 2016 to December 2017). Our study confirmed that the environmental conditions of the study area were suitable for M. leidyi growth. In addition, due to the combined effects of temperature, salinity and food availability M. leidyi was able to survive during winter months. Particular attention was then given to zooplankton abundance and community changes between two time periods: before and after M. leidyi arrival. Statistical analysis revealed significant differences in zooplankton abundance between the two time periods and a decrease in species diversity and evenness was observed during summer 2016.


2004 ◽  
Vol 61 (2) ◽  
pp. 219-229 ◽  
Author(s):  
Sanna Rönkkönen ◽  
Evald Ojaveer ◽  
Tiit Raid ◽  
Markku Viitasalo

We used the longest available weight-at-age (WAA) time series (from 1950 to 1999) for Baltic herring (Clupea harengus membras L.) in the Gulf of Finland to investigate which environmental factors affect Baltic herring growth. The relationships among WAAs, annual weight increments, and growth rates for different herring year classes, water salinity, temperature, zooplankton abundance, and biomass, as well as stock sizes of herring, sprat, and cod, were evaluated. Our results showed that in the Gulf of Finland, herring weight and growth rate correlated positively with salinity, and WAA correlated positively with the abundance of the marine zooplankton species Pseudocalanus minutus elongatus. A density-dependent mechanism was not likely to explain the changes in herring WAA in the Gulf of Finland, because no significant correlation between herring WAAs and herring abundance could be found. Instead, the zooplankton community structure changed during the research period, which supports the theory of bottom-up controlling mechanism. A strong negative correlation between herring weight and sprat biomass may indicate competition for food between these species.


2004 ◽  
Vol 61 (11) ◽  
pp. 2111-2125 ◽  
Author(s):  
Richard P Barbiero ◽  
Marc L Tuchman

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.


2012 ◽  
Vol 69 (1) ◽  
pp. 8-22 ◽  
Author(s):  
Simon P. R. Greenstreet ◽  
Helen M. Fraser ◽  
Stuart I. Rogers ◽  
Verena M. Trenkel ◽  
Stephen D. Simpson ◽  
...  

Abstract Greenstreet, S. P. R., Fraser, H. M., Rogers, S. I., Trenkel, V. M., Simpson, S. D., and Pinnegar, J. K. 2012. Redundancy in metrics describing the composition, structure, and functioning of the North Sea demersal fish community. – ICES Journal of Marine Science, 69: 8–22. Broader ecosystem management objectives for North Sea demersal fish currently focus on restoring community size structure. However, most policy drivers explicitly concentrate on restoring and conserving biodiversity, and it has not yet been established that simply restoring demersal fish size composition will be sufficient to reverse declines in biodiversity and ensure a generally healthy community. If different aspects of community composition, structure, and function vary independently, then to monitor all aspects of community general health will require application of a suite of metrics. This assumes low redundancy among the metrics used in any such suite and implies that addressing biodiversity issues specifically will require explicit management objectives for particular biodiversity metrics. This issue of metric redundancy is addressed, and 15 metrics covering five main attributes of community composition, structure, and function are applied to groundfish survey data. Factor analysis suggested a new interpretation of the metric information and indicated that a minimum suite of seven metrics was necessary to ensure that all changes in the general health of the North Sea demersal fish community were monitored properly. Covariance among size-based and species-diversity metrics was low, implying that restoration of community size structure would not necessarily reverse declines in species diversity.


2011 ◽  
Vol 83 (2) ◽  
pp. 575-588 ◽  
Author(s):  
Charrid Resgalla Jr

This paper presents information from different sampling surveys carried out along the Santa Catarina coast in order to outline the biogeographical characteristics of the zooplankton in this region and identify species or groups of species with potential use as bioindicators. Based on a checklist of species of the zooplankton community in the state, it was observed that, in the warmer months of the year, the fauna is similar to that of the states of Paraná and São Paulo (e.g. Creseis virgula f. virgula, Penilia avirostris; Acartia lilljeborgi and Oithona oswaldocruzi), while in the colder months there are coastal representatives of the fauna of Rio Grande do Sul (e.g. Acartia tonsa). However, the zooplankton consists predominantly of warm water species for most of the year, which is typical of Tropical Shelf Waters. Various species of zooplankton can be used as hydrological indicators, enabling a distinction to be made between coastal waters which are influenced by continental inputs (e.g. Paracalanus quasimodo and Parvocalanus crassirostris), common in the north of the state, and processes of upwelling (e.g. Podon intermedius) and the influence of the Subtropical Shelf Front (e.g. Pleopis polyphemoides), coming from the south. The different environments investigated present a zooplankton abundance that depends on the influence of continental inputs and the possibility of their retaining and contribution for the coastal enrichment, which varies seasonally


2012 ◽  
Vol 4 (2) ◽  
Author(s):  
Arief Rachman ◽  
Elly Asniariati

<p>Banggai Sea is an interesting ecosystem due to mixing influences from Banda Sea in the west and Maluccas Sea in the east. Therefore, a unique zooplankton community structure and specific distribution pattern should be found in this area. This research was carried on using Baruna Jaya VIII research vessel and samples were collected in 14 sampling stations. Vertical towing using NORPAC plankton net (300 μm) was conducted to collect zooplankton samples. Result showed that inner Mesamat Bay had the lowest abundance of zooplankton, probably due to low water quality resulted from anthropogenic activity. Meanwhile the strait between Liang and Labobo Island had the highest zooplankton abundance in Banggai Sea. Calanoids was the dominant zooplankton taxa in the ecosystem and contributing 55.7% of total density of zooplankton community. The highest importance value made this taxa to be very important factor that regulates the lower trophic level organisms. Results also showed that zooplankton was distributed nearly uniform in eastern but aggregated to several stations in western Banggai Sea. Zooplankton abundance was higher in the central of Banggai Sea, compared to western and eastern area. According to Bray-Curtis clustering analysis the strait between Liang and Labobo Island has unique zooplankton community structure. This might happened due to mixing of water from two highly productive seas that influenced the Banggai Sea ecosystem. From this research we conclude that this strait probably was the zooplankton hot spot area which might also indicate that this area also a hot spot of fishes in the Banggai Sea.</p><p>Keywords: spatial distribution, zooplankton, community structure, hot spot, Banggai</p>


Sign in / Sign up

Export Citation Format

Share Document