Calanoid copepods in central Chilean and Chilean Patagonian lakes (33-55°S, Chile), probable ecological key role in pelagic environments

The Patagonian lakes (38-55°S) are characterized by their marked oligotrophy, low number of species of crustacean zooplankton, and a marked predominance of calanoid copepods. Within this context, we considered that a review about the ecology of the zooplankton in central and southern Chilean lakes would be useful, aiming to understand the ecological importance of this group. Data obtained from the literature for freshwater bodies in central and southern Chilean lakes were analysed. In addition, data from various bays with widely differing trophic status in Llanquihue Lake were examined. The results revealed the existence of originally pristine and oligotrophic sites, all with a low number of species and marked calanoid dominance. However, in northern Patagonia there are many lakes in which human intervention has caused an increase in phytoplankton activity, with a consequent replacement of calanoid copepods by daphniid cladocerans. Other important factors that could affect the zooplankton community would be fish predation, which is due to generate a decrease in large-bodied groups of zooplankton; and stress due to exposure to natural ultraviolet radiation. Ecological, biogeographical, and evolutionary topics are discussed within the framework described.

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Zooplankton Community Response to Seasonal Hypoxia: A Test of Three Hypotheses

Diversity ◽

10.3390/d12010021 ◽

2020 ◽

Vol 12 (1) ◽

pp. 21 ◽

Cited By ~ 2

Author(s):

Julie E. Keister ◽

Amanda K. Winans ◽

BethElLee Herrmann

Keyword(s):

Community Structure ◽

Puget Sound ◽

Temporal Stability ◽

Zooplankton Community ◽

Community Response ◽

Crustacean Zooplankton ◽

Zooplankton Abundance ◽

Calanoid Copepods ◽

Low Oxygen ◽

Seasonal Hypoxia

Several hypotheses of how zooplankton communities respond to coastal hypoxia have been put forward in the literature over the past few decades. We explored three of those that are focused on how zooplankton composition or biomass is affected by seasonal hypoxia using data collected over two summers in Hood Canal, a seasonally-hypoxic sub-basin of Puget Sound, Washington. We conducted hydrographic profiles and zooplankton net tows at four stations, from a region in the south that annually experiences moderate hypoxia to a region in the north where oxygen remains above hypoxic levels. The specific hypotheses tested were that low oxygen leads to: (1) increased dominance of gelatinous relative to crustacean zooplankton, (2) increased dominance of cyclopoid copepods relative to calanoid copepods, and (3) overall decreased zooplankton abundance and biomass at hypoxic sites compared to where oxygen levels are high. Additionally, we examined whether the temporal stability of community structure was decreased by hypoxia. We found evidence of a shift toward more gelatinous zooplankton and lower total zooplankton abundance and biomass at hypoxic sites, but no clear increase in the dominance of cyclopoid relative to calanoid copepods. We also found the lowest variance in community structure at the most hypoxic site, in contrast to our prediction. Hypoxia can fundamentally alter marine ecosystems, but the impacts differ among systems.

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First fecundity observations on female copepods from three northern Patagonian lakes (Pellaifa, Calafquén, Panguipulli; Chile)

Crustaceana ◽

10.1163/15685403-00003881 ◽

2019 ◽

Vol 92 (8) ◽

pp. 897-905

Author(s):

Patricio De los Ríos ◽

Jorge Farias-Avendaño ◽

Maria J. Suazo

Keyword(s):

Community Structure ◽

Interspecific Competition ◽

Crustacean Zooplankton ◽

Calanoid Copepods ◽

Predator Prey ◽

Total Length ◽

Patagonian Lakes ◽

Egg Number

Abstract The crustacean zooplankton in Chilean Patagonian lakes is characterized by a marked dominance of calanoid copepods when under an oligotrophic status. The aim of the present study was to analyse the number of eggs and the relation of that feature with the total length of females of calanoid and cyclopoid copepods reported in three northern Chilean Patagonian lakes. The calanoid copepods found were Boeckella gracilipes in Lake Pellaifa and Tumeodiaptomus diabolicus in the lakes Panguipulli and Calafquén, whereas the cyclopoid Mesocyclops araucanus was found in the lakes Pellaifa and Calafquén. For calanoid copepods, high egg numbers were found and thus also a high value for the ratio of egg number per female length in Lake Panguipulli, whereas for M. araucanus a high value was found in Lake Pellaifa. These differences would presumably be associated with community structure, specifically predator-prey relationships and possibly other interactions, as, e.g., potential interspecific competition.

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Effects of Low Concentrations of Cadmium on the Crustacean Zooplankton Community of an Artificially Acidified Lake

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f87-292 ◽

1987 ◽

Vol 44 (S1) ◽

pp. s163-s172 ◽

Cited By ~ 13

Author(s):

S. G. Lawrence ◽

M. H. Holoka

Keyword(s):

Zooplankton Community ◽

Toxic Effects ◽

Crustacean Zooplankton ◽

Individual Species ◽

Calanoid Copepods ◽

Bosmina Longirostris ◽

Low Concentrations ◽

Total Community

The toxic effects of cadmium to total community and individual species of zooplankton generally decreased as pH of the lake was experimentally lowered over a number of years by additions of acids. The biomass of crustacean zooplankton held in small impoundment systems suspended in the lake for fourteen days was reduced by 60–70% when pH was 6.7–6.8 and concentrations of Cd were maintained at 1 μg∙L−1, and by 70–80% when Cd was at 3 μg∙L−1. At a pH of 5.9, however, biomass was reduced only 20–30% in concentrations of Cd of 1 μg∙L−1, and at pH 5.6, biomass decreased by only 20% when subjected to 3 μg∙L−1 Cd. The cladocerans Bosmina longirostris and Holopedium gibberum were the most sensitive to cadmium. Cladocerans were more sensitive to cadmium than calanoid copepods, and both these groups were more sensitive then cyclopoid copepods. The decrease in toxicity of cadmium with increasing H+ may be analogous to the inhibition of uptake of cadmium by calcium.

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Fish predation effects on body length of planktonic cladocerans and copepods in Chilean lakes

Crustaceana ◽

10.1163/15685403-00003472 ◽

2015 ◽

Vol 88 (10-11) ◽

pp. 1193-1199 ◽

Cited By ~ 2

Author(s):

Patricio De los Ríos-Escalante

Keyword(s):

Body Length ◽

Zooplankton Community ◽

Fish Predation ◽

Total Body Length ◽

Calanoid Copepods ◽

Main Prey ◽

Species Numbers ◽

Zooplankton Size ◽

Predation Effects ◽

Total Body

The zooplankton assemblages in Chilean lakes are characterized by their markedly low species numbers and dominance of calanoid copepods. Nevertheless, the effects of zooplanktivorous fish predation on zooplankton size in these communities have not yet been studied in detail. The aim of the present study was to analyse the total length in the main groups of zooplanktonic crustaceans in Chilean lakes: Copepoda: Calanoida, and Cladocera: Daphniidae, as well as “small cladocerans” (specifically the families Bosminidae and Chydoridae). The results revealed that in the presence of fish, total body length decreased significantly for calanoid copepods, whereas for other groups that presence has no significant effect. In sites with fishes, daphniids are significantly larger in comparison with the other groups of the zooplankton community, whereas in sites without fishes calanoids are significant larger in comparison with those other groups. These results would indicate that calanoids would be the main prey for zooplanktivorous fishes in Chilean lakes. Similar results have been reported for Argentinean Patagonian lakes.

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Use of Null Models to Explain Crustacean Zooplankton Assemblages in Northern Patagonian Lakes (Chile) with and Without Mixotrophic Ciliates

Crustaceana ◽

10.1163/001121611x584343 ◽

2011 ◽

Vol 84 (9) ◽

pp. 1061-1068 ◽

Cited By ~ 2

Author(s):

Patricio De Los Ríos-Escalante ◽

Stefan Woelfl

Keyword(s):

Null Model ◽

Field Work ◽

Study Data ◽

Null Models ◽

Crustacean Zooplankton ◽

Species Number ◽

Calanoid Copepods ◽

Patagonian Lakes ◽

Study Sites ◽

Mixotrophic Ciliates

AbstractThe zooplankton assemblages in deep, mostly oligotrophic northern Patagonian lakes are characterized by a low species number and a marked dominance of calanoid copepods, as well as often by the presence of large mixotrophic ciliates (Stentor). In the present study, data collected in field work on four northern Patagonian lakes were analysed using co-occurrence of null models, with the aim to determine potential regulating factors for the observed crustacean and mixotrophic ciliate assemblages, using a presence-absence matrix. The null model uses species co-occurrence, and the basis of this model is that the species associations observed are random. The results revealed the absence of regulating factors and indicate that the sites are relatively homogeneous, with low species numbers, and similar plankton assemblages at all study sites. This finding coincides with similar descriptions for zooplankton assemblages in other Chilean Patagonian lakes.

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Use of null models to explain crustacean zooplankton assemblages in North Patagonian lakes with presence or absence of mixotrophic ciliates (38°S, Chile)

Crustaceana ◽

10.1163/15685403-00003634 ◽

2017 ◽

Vol 90 (3) ◽

pp. 311-319 ◽

Cited By ~ 8

Author(s):

Patricio De los Ríos-Escalante ◽

Stefan Woelfl

Keyword(s):

Species Richness ◽

Random Effect ◽

Null Model ◽

Model Analysis ◽

Null Models ◽

Crustacean Zooplankton ◽

Calanoid Copepods ◽

The Third ◽

Patagonian Lakes ◽

Mixotrophic Ciliates

Zooplankton assemblages in Northern Patagonian lakes are characterized by a low species richness and a marked dominance of calanoid copepods. The aim of the present study was to do a null model analysis to explain the composition of the zooplankton assemblages in two North Patagonian lakes. The first aspect to which null model analysis was applied was species co-occurrence, and there the model indicates that the species associations found are not random. The second aspect was niche sharing, and that analysis denotes that the species do not share niches. The third aspect tested was size overlap, and the model there denotes that the species have no size overlap. The results obtained indicate that the sites are relatively homogeneous, which would explain the random effect in species co-ocurrence, whereas the absence of niche sharing is due to the presence of different energetic resources at both sites investigated, which would separate the niche of each species from those of other faunistic elements. Finally, the third application of the null model analysis demonstrates that there is no competition among the species reported upon herein.

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Crustacean zooplankton in lakes and reservoirs of temperate and tropical regions: variation with trophic status

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f04-178 ◽

2005 ◽

Vol 62 (2) ◽

pp. 348-361 ◽

Cited By ~ 100

Author(s):

Ricardo Pinto-Coelho ◽

Bernadette Pinel-Alloul ◽

Ginette Méthot ◽

Karl E Havens

Keyword(s):

Species Richness ◽

Chlorophyll A ◽

Total Phosphorus ◽

Trophic Status ◽

Zooplankton Community ◽

Crustacean Zooplankton ◽

Eutrophic Lakes ◽

Crustacean Species ◽

Tropical Regions ◽

Lakes And Reservoirs

The influence of trophic status on the crustacean zooplankton community was investigated in lakes and reservoirs in temperate and subtropical-tropical regions. We tested if there is a consistent relationship between crustacean species richness, assemblages, and abundance and trophic indices such as total phosphorus and chlorophyll a. We also examined if these patterns differ between regions. Cumulative species richness and assemblages varied among regions. The greatest number of crustacean species was found in the temperate oligotrophic region with the largest number of lakes sampled. However, cumulative species richness was similar in temperate and subtropicaltropical regions when comparing subsets with a similar number of lakes and reservoirs. The relationships between species richness and latitude or trophic status were difficult to assess owing to imbalance among regions in number of lakes and reservoirs sampled and to biogeography and fish predation potential influences. Trophic status was associated with changes in abundance of all major crustacean zooplankton groups. Eutrophic ecosystems supported greater crustacean abundances at all latitudes. However, cladocerans and cyclopoids were more abundant in eutrophic lakes and reservoirs, whereas calanoids were more abundant in temperate oligotrophic lakes. Total phosphorus was found to be a better predictor of the biomass of major crustacean groups than chlorophyll a in all regions.

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Daily vertical distribution of zooplankton in two oligo-mesotrophic north Patagonian lakes (39° S, Chile).

Brazilian Journal of Biology ◽

10.1590/1519-6984.227942 ◽

2020 ◽

Author(s):

P. De Los Ríos-Escalante ◽

P. Valdivia ◽

S. Woelfl

Keyword(s):

Ultraviolet Radiation ◽

Vertical Migration ◽

Daphnia Pulex ◽

Fish Predation ◽

Early Morning ◽

Ceriodaphnia Dubia ◽

Crustacean Zooplankton ◽

Zooplankton Species ◽

Patagonian Lakes ◽

Ultraviolet Radiation Exposure

Abstract The zooplankton communities often exhibit daily vertical migrations to avoid natural ultraviolet radiation and/or fish predation. However there is no information on this topic in Chilean North Patagonian lakes up to date. Therefore, this study deals with a first characterization of plankton crustacean daily vertical migration in two temperate, oligotrophic lakes (Villarrica and Panguipulli lakes, 39°S) in Southern Chile. Zooplankton were collected at different depths intervals (0-10m, 10-20 m, 20-30m, 30-40m) at early morning, middle day, evening and night in the studied site. The results revealed that zooplankton species (Daphnia pulex, Ceriodaphnia dubia, Neobosmina chilensis, Mesocyclops araucanus, and Tropocyclops prasinus) are abundant in surface zones at night, early morning and evening, whereas at middle day the zooplankton abundances are high at deep zones. The results agree with observations for Argentinean and North American lakes where these daily migration patterns in crustacean zooplankton species were reported due mainly natural ultraviolet radiation exposure, whereas for northern hemisphere lakes the vertical migration is due to combined effect of natural ultraviolet radiation and fish predation exposure.

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An update on the global stressors and constraints affecting Daphnia populations in large Chilean Patagonian lakes (39-51°S)

Crustaceana ◽

10.1163/15685403-00003701 ◽

2017 ◽

Vol 90 (11-12) ◽

pp. 1501-1516 ◽

Cited By ~ 1

Author(s):

Patricio De los Ríos Escalante ◽

Fátima Kies ◽

Francisco Correa-Araneda

Keyword(s):

Ultraviolet Radiation ◽

Fish Predation ◽

Molar Ratio ◽

Field Observations ◽

Stress Effects ◽

Number Of Species ◽

Patagonian Lakes ◽

Essential Nutrient ◽

Zooplankton Communities ◽

Mineral Concentrations

The zooplankton communities in Chilean Patagonian lakes (39-51°S) are characterized by the low presence of daphniid cladocerans, i.e., under conditions of the usual native oligotrophy and, thus, low mineral concentrations. Nevertheless, from some northern Patagonian lakes (39-41°S) a marked abundance of daphniids has been reported. According to the literature, as well as evidence from field observations, the main causes of such marked changes in the local zooplankton assemblages would be changes in phytoplankton quantity and quality, providing increased energetic resources for the zooplankton communities. Such energetic resources might decrease the stress effects of low calcium concentrations, as calcium constitutes an essential nutrient for caparace formation in Daphniidae; in addition, energetic expenses needed to perform vertical migrations due to fish predation and exposure to natural ultraviolet radiation can better be provided for. This is a markedly different situation compared to North Patagonian lakes, where daphniid abundance and number of species are related only to phytoplankton quantity and quality in term of phosphorus/nitrogen molar ratio.

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Observations on crustacean zooplankton in two connected north Patagonian lakes (Calafquén-Pellaifa, 39°S, Chile)

Crustaceana ◽

10.1163/15685403-00003870 ◽

2019 ◽

Vol 92 (6) ◽

pp. 665-673

Author(s):

Patricio De los Ríos ◽

Jorge Farias-Avendaño ◽

Maria J. Suazo

Keyword(s):

Species Composition ◽

Interspecific Competition ◽

Size Structure ◽

Zooplankton Community ◽

Null Models ◽

Crustacean Zooplankton ◽

Human Intervention ◽

Patagonian Lakes ◽

Biodiversity Index

Abstract The northern Patagonian lakes (38-41°S), are characterized by their location in catchment basins that have been markedly altered through human intervention. In those basins, the original native, perennial forest has been replaced by towns, villages and agricultural zones. The present study was done in two interconnected north Patagonian lakes (the lakes Calafquén and Pellaifa), where the species composition of the crustacean zooplankton community was compared, using a biodiversity index and size-structure null models. The results denoted the presence of marked differences between both sites, Calafquén lake being inhabited by less species and in general showing lower abundances of individuals in comparison to Pellaifa lake. The results of size-structure null models revealed the absence of interspecific competition for both sites. The obtained results would agree with similar observations for other northern Patagonian lakes in Argentina and Chile.

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