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The structuring role of fish in Greenland lakes: an overview based on contemporary and paleoecological studies of 87 lakes from the low and the high Arctic

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Lakes in Greenland are species-poor ecosystems and many are fishless. We studied the structuring role of fish in lakes in high- and low-Arctic Greenland. Major differences were observed in the trophic structure of the 87 lakes studied. Pelagic zooplankton biomass was on average 3–4-fold higher in the fishless lakes and dominated by large-bodied taxa such as Daphnia, the phyllopod Branchinecta and the tadpole shrimp Lepidurus. In contrast, small-bodied crustaceans dominated the lakes with fish. Analysis of microcrustacean remains in the surface sediment and contemporary benthic invertebrates also showed a marked influence of fish on community structure and the size of the taxa present. The cascading effect of fish on the microbial communities was modest, and no differences were observed for chlorophyll a. The cascading effect of fish on invertebrates depended, however, on the species present, being largest between fishless lakes and lakes hosting only sticklebacks (Gasterosteus aculeatus), while lakes with both Arctic charr (Salvelinus arcticus) and stickleback revealed a more modest response, indicating that presence of charr modulates the predation effect of sticklebacks. It is predicted that more lakes in Greenland will be colonised by fish in a future warmer climate, and this will substantially alter these vulnerable ecosystems.
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TRENDS IN AQUATIC ECOLOGY II
The structuring role of fish in Greenland lakes: an overview
based on contemporary and paleoecological studies of 87
lakes from the low and the high Arctic
Erik Jeppesen .Torben L. Lauridsen .Kirsten S. Christoffersen .
Frank Landkildehus .Peter Geertz-Hansen .Susanne Lildal Amsinck .
Martin Søndergaard .Thomas A. Davidson .Frank Rige
´t
Received: 26 April 2017 / Revised: 19 June 2017 / Accepted: 21 June 2017 / Published online: 19 July 2017
ÓSpringer International Publishing AG 2017
Abstract Lakes in Greenland are species-poor
ecosystems and many are fishless. We studied the
structuring role of fish in lakes in high- and low-Arctic
Greenland. Major differences were observed in the
trophic structure of the 87 lakes studied. Pelagic
zooplankton biomass was on average 3–4-fold higher
in the fishless lakes and dominated by large-bodied
taxa such as Daphnia, the phyllopod Branchinecta and
the tadpole shrimp Lepidurus. In contrast, small-
bodied crustaceans dominated the lakes with fish.
Analysis of microcrustacean remains in the surface
sediment and contemporary benthic invertebrates also
showed a marked influence of fish on community
structure and the size of the taxa present. The
cascading effect of fish on the microbial communities
was modest, and no differences were observed for
chlorophyll a. The cascading effect of fish on inver-
tebrates depended, however, on the species present,
being largest between fishless lakes and lakes hosting
only sticklebacks (Gasterosteus aculeatus), while
lakes with both Arctic charr (Salvelinus arcticus)
and stickleback revealed a more modest response,
indicating that presence of charr modulates the
predation effect of sticklebacks. It is predicted that
more lakes in Greenland will be colonised by fish in a
future warmer climate, and this will substantially alter
these vulnerable ecosystems.
Guest editors: Koen Martens, Sidinei M. Thomaz,
Diego Fontaneto & Luigi Naselli-Flores / Emerging
Trends in Aquatic Ecology II
E. Jeppesen (&)T. L. Lauridsen F. Landkildehus
S. L. Amsinck M. Søndergaard T. A. Davidson
Department of Bioscience, Aarhus University, Silkeborg,
Denmark
e-mail: ej@bios.au.dk
E. Jeppesen T. L. Lauridsen
Arctic Research Centre, Aarhus University, Aarhus,
Denmark
E. Jeppesen T. L. Lauridsen M. Søndergaard
Sino-Danish Centre for Education and Research, Beijing,
China
K. S. Christoffersen
Department of Biology, University of Copenhagen,
Copenhagen, Denmark
P. Geertz-Hansen
Department of Inland Fisheries, DTU-AQUA, Silkeborg,
Denmark
F. Rige
´t
Department of Bioscience, Aarhus University, Roskilde,
Denmark
K. S. Christoffersen
Department of Arctic Biology, University Center in
Svalbard, Longyearbyen, Norway
F. Rige
´t
Greenland Institute of Natural Resources, Nuuk,
Greenland
123
Hydrobiologia (2017) 800:99–113
DOI 10.1007/s10750-017-3279-z
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... These fishless ponds and lakes are characterised by high abundances of the herbivorous zooplankton Daphnia, an important taxon for the structure and functioning of many freshwater communities and food-webs across the northern hemisphere (e.g. Jeppesen et al., 2017;O'Brien et al., 2004;Stross et al., 1980). Climate change is predicted to exert both direct and indirect effects on Arctic zooplankton assemblages. ...
... Despite a shorter temperature gradient, a similar decrease in zooplankton diversity towards high latitudes has been shown for both Arctic lakes (Patalas, 1990) and ponds (e.g. Jeppesen et al., 2017;Rautio & Vincent, 2006). ...
... A number of lake features could also contribute to these patterns, including local selective pressures such as the presence, composition, and abundances of fish populations, which may have a strong effect on zooplankton assemblage composition (Brooks & Dodson, 1965;Hessen et al., 2006). For example, large-bodied Daphnia species are often the dominant species in many fishless ponds and lakes in the Arctic (Edmondson, 1955;Jeppesen et al., 2017;van Geest et al., 2007), whereas daphnids are usually absent in lakes with fish (O'Brien et al., 2004). Our results also showed this pattern, as D. pulex was found in nearly 50% of our studied lakes in Svalbard, Greenland, and Alaska, whereas they were not found in any of the larger lakes with fish in Fennoscandia. ...
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• Arctic freshwaters are facing multiple environmental pressures, including rapid climate change and increasing land-use activities. Freshwater plankton assemblages are expected to reflect the effects of these stressors through shifts in species distributions and changes to biodiversity. These changes may occur rapidly due to the short generation times and high dispersal capabilities of both phyto- and zooplankton. • Spatial patterns and contemporary trends in plankton diversity throughout the circumpolar region were assessed using data from more than 300 lakes in the U.S.A. (Alaska), Canada, Greenland, Iceland, the Faroe Islands, Norway, Sweden, Finland, and Russia. The main objectives of this study were: (1) to assess spatial patterns of plankton diversity focusing on pelagic communities; (2) to assess dominant component of β diversity (turnover or nestedness); (3) to identify which environmental factors best explain diversity; and (4) to provide recommendations for future monitoring and assessment of freshwater plankton communities across the Arctic region. • Phytoplankton and crustacean zooplankton diversity varied substantially across the Arctic and was positively related to summer air temperature. However, for zooplankton, the positive correlation between summer temperature and species numbers decreased with increasing latitude. Taxonomic richness was lower in the high Arctic compared to the sub- and low Arctic for zooplankton but this pattern was less clear for phytoplankton. Fennoscandia and inland regions of Russia represented hotspots for, respectively, phytoplankton and zooplankton diversity, whereas isolated regions had lower taxonomic richness. Ecoregions with high α diversity generally also had high β diversity, and turnover was the most important component of β diversity in all ecoregions. • For both phytoplankton and zooplankton, climatic variables were the most important environmental factors influencing diversity patterns, consistent with previous studies that examined shorter temperature gradients. However, barriers to dispersal may have also played a role in limiting diversity on islands. A better understanding of how diversity patterns are determined by colonisation history, environmental variables, and biotic interactions requires more monitoring data with locations dispersed evenly across the circumpolar Arctic. Furthermore, the importance of turnover in regional diversity patterns indicates that more extensive sampling is required to fully characterise the species pool of Arctic lakes.
... Fish often play an important role in lake food webs by feeding selectively on large, slow-moving and/or highly nutritious prey items, leading to shifts in the size structure and dominance hierarchies of invertebrate communities (Jeppesen et al., 2010(Jeppesen et al., , 2017Ruppert et al., 2017). In addition to the direct impacts on abundance and community composition, fish predation risk may have indirect impacts by restricting the habitat and resource use of invertebrates (Bernot and Turner, 2001). ...
... Table 5 Sample sizes (n), means and ranges of δ 13 C and δ 15 N values (in ‰), as well as isotopic niche areas based on sample-size corrected (SEA C ) and Bayesian estimates (modes, upper and lower 95% credibility intervals) of Standard Ellipse Areas (SEA B ) estimated using SIBER package in R (Layman et al., 2007) for benthic invertebrates sampled from treated and untreated lakes before and after the rotenone treatment. (e.g., Jeppesen et al., 2017). The reduced fish predation and high recolonization rates of large, mobile benthic invertebrates from refugia (i.e., connected untreated lakes and streams; Pham et al., 2018;Bellingan et al., 2019) likely explains the rapid increase in abundance of predatory invertebrates and some large collectors (e.g., Gammaridae) in our treated lakes. ...
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... As we discuss in more detail below, threespine stickleback are not native to Lake Constance, but are currently hyperabundant, representing ∼28% of the total fish biomass, and are the second most abundant fish species in the lake (Zimmermann, 2002;Alexander et al., 2016). Large populations of stickleback are known from other large oligotrophic lakes within their natural range, e.g., in Greenland, Alaska, and the West Coast of Canada (Greenbank and Nelson, 1959;Reimchen, 1992a;Bergersen, 1996;Jeppesen et al., 2017), but such a hyperabundance is rare in quantitative assessments of lakes that are as large and species rich as Constance. As such, understanding the invasion and establishment of the lake Constance population is also of considerable interest for ecosystem management and conservation. ...
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... While Arctic ponds generally have low species diversity of zooplankton, they can reach relatively high abundances compared to other freshwater environments, largely because of the absence of fish (Rautio et al. 2011). The absence of fish also allows large-bodied zooplankton, such as Daphnia spp., to dominate some Arctic zooplankton communities (Christoffersen et al. 2008;Jeppesen et al. 2017). Several studies have suggested that the carnivorous copepod Heterocope septentrionalis, also observed here, can determine the species of Daphnia present in Arctic freshwaters by promoting the dominance of D. middendorffiana over the smaller D. pulex (Dzialowski et al. 2004;O'Brien and Luecke 2011). ...
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... Fish-induced trophic cascades shifted the zooplankton composition from large taxa towards small-bodied crustaceans, in particular if sticklebacks (Gasterosteus aculeatus) were the single fish species present. Invasion of currently fishless lakes by fish will hence substantially modify these lakes (Jeppesen et al., 2017). ...
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... As we discuss in more detail below, threespine stickleback are not native to Lake Constance, but are currently hyperabundant, representing ∼28% of the total fish biomass, and are the second most abundant fish species in the lake (Zimmermann, 2002;Alexander et al., 2016). Large populations of stickleback are known from other large oligotrophic lakes within their natural range, e.g., in Greenland, Alaska, and the West Coast of Canada (Greenbank and Nelson, 1959;Reimchen, 1992a;Bergersen, 1996;Jeppesen et al., 2017), but such a hyperabundance is rare in quantitative assessments of lakes that are as large and species rich as Constance. As such, understanding the invasion and establishment of the lake Constance population is also of considerable interest for ecosystem management and conservation. ...
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Greenland and the Tibetan Plateau, also known as the third pole, are both cold environments where anthropo-genic activities are relatively weak. There are multitudinous lakes in both regions, especially in Greenland, where small water bodies are continuously created as glaciers retreat. It is unclear whether the community structure and community assembly mechanisms of these water bodies are consistent with those of lakes in the Tibetan Plateau that were indirectly influenced by glaciers. In addition, due to different evolution times of the lakes, differences of microbial diversity, especially at the sub-species level, are feasible but not yet reported. Microbial compositions in lake water and sediment were investigated based on high-throughput sequencing of 16S rRNA genes. The oligotyping analysis revealed disproportionally distributed bacterial oligotypes in lakes between the two different areas. Moreover, microbial macrodiversity and intra-operational taxonomic units microdiversity is significantly higher in Greenland lakes which experiencing early lake ontogeny. Microbial community composition and func-tionality significantly distinguished between the two regions and habitats. Multivariate analysis together with null model tests demonstrated that deterministic processes largely controlled the patterns of community structure in the sediment, while stochastic processes are more important for those in pelagic water in both regions. Microbes may be further subject to N and P co-limitation in line with the evolution of lake ecosystems. The obtained results could help us understand evolution trajectory of these polar lakes under the future climate change scenario.
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