In many regions across the globe, extreme weather events such as storms have increased in frequency, intensity, and duration due to climate change. Ecological theory predicts that such extreme events should have large impacts on ecosystem structure and function. High winds and precipitation associated with storms can affect lakes via short-term runoff events from watersheds and physical mixing of the water column. In addition, lakes connected to rivers and streams will also experience flushing due to high flow rates. Although we have a well-developed understanding of how wind and precipitation events can alter lake physical processes and some aspects of biogeochemical cycling, our mechanistic understanding of the emergent responses of phytoplankton communities is poor. Here we provide a comprehensive synthesis that identifies how storms interact with lake and watershed attributes and their antecedent conditions to generate changes in lake physical and chemical environments.Such changes can restructure phytoplankton communities and their dynamics, as well as result in altered ecological function (e.g., carbon, nutrient and energy cycling) in the short-and long-term. We summarize the current understanding of storm-induced phytoplankton dynamics, identify knowledge gaps with a systematic review of the literature, and suggest future research directions across a gradient of lake types and environmental conditions.

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Pelagic zooplankton samples from Lake Biwa, Japan, collected monthly since 1971, were analyzed for biomass and body size structure. Our aim was to clarify the relative effects of food availability and global warming vs. top‐down control by fish predation on long‐term trends. Annual mean biomass and density‐weighted body size were calculated and compared with water temperature, total phosphorus (TP), as a proxy of food amount, and catch per unit effort (CPUE) of Ayu (Plecoglossus altivelis altivelis), as a proxy of planktivorous fish predation pressure. Mean water temperature above 20 m increased by 0.94°C. TP increased until 1974 and then decreased until 1985, becoming stable after that. Ayu CPUE increased until 1987 and then declined. The study period can be divided into two nutritional phases: a high TP phase (1971–1985) and a low‐stable TP phase (1986–2010). Five zooplankton taxa, Eodiaptomus japonicus, Cyclopoida spp., Daphnia spp., Bosmina longirostris, and Diaphanosoma orientalis, were continuously dominant. Annual mean total crustacean biomass varied from 0.3 to 3.6 g dry weight m−2, slightly decreasing until 1993 but increasing thereafter. Generalized linear models showed that annual mean body sizes were affected by temperature and CPUE, whereas annual mean biomass was affected by TP and CPUE. These had no effect during the high TP phase, whereas only CPUE affected both traits during the low‐stable TP phase. We concluded that zooplankton biomass and body size long‐term trends were mostly influenced by fish predation and that eutrophication and global warming impacts might be affected by top‐down control.

The calanoid copepod Eurytemora affinis dominates the zooplankton communities in most northern hemisphere estuaries. A recurrent behavior noticed in several estuaries suggests that this species maintains its horizontal position through vertical migration. In order to investigate this behavioral strategy in detail, we sampled E. affinis nauplii, copepodids and adults at high frequency at a fixed point in the low salinity zone of the Seine estuary. We took water samples in sub-surface and near bottom during a 12-and 50-h tide cycle, in May 2002 and May 2004, respectively. Since nauplii have weak swimming capabilities compared to copepodid and adult stages, we proposed here to consider them as passive particles. The variation of the relative abundances of nauplii to older stages regarding the vertical position was therefore viewed as direct evidence of the behavior of later stages. We showed that copepodids and adults tried to stay close to the bottom during the ebb, were re-suspended in the water column 1 h after the low tide during the maximum current velocity, and then vertically migrated back to the bottom layer when current velocity decreased. We also showed that copepodids behaved as adults, with only a lower velocity, taking more time to go near the bottom.

Studies on the behavior of copepods require both an appropriate experimental design and the means to perform objectively verifiable numerical analysis. Despite the growing number of publications on copepod behavior, it has been difficult to compare these studies. In this study, we studied two species of copepods, Eurytemora affinis and Pseudodiaptomus annandalei, and employed recently developed scaling and non-scaling methodology to investigate the effects of density and volume on the swimming behavior of individual organisms in still water. We also compared the results of two-and three-dimensional projections of the swimming tracks. A combination of scale-dependent and scale-independent analysis was found to characterize a number of behavioral observations very effectively. We discovered that (i) density has no effect except to increase the time spent in the swimming state of ''breaking'', (ii) smaller volumes resulted in more complex trajectories, and larger volumes, like density, increased the time spent in the swimming state ''breaking'', and (iii) three-dimensional projections gave a more accurate estimation of speed and the time spent cruising. When only a vertical 2D projection was used, ''cruising'' could be confused with ''sinking''. These results indicate that both experimental conditions and the selection of 2D or 3D projection have important implications regarding the study of copepod behavior. The development of standardized procedures with which to compare the observations made in different studies is an issue of particular urgency.

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Summary Life history traits of the freshwater calanoid copepod Eodiaptomus japonicus from Lake Biwa were examined in the laboratory. Four different food concentrations (FC, 103, 5 × 103, 104 and 5 × 104 cells mL−1) and two temperature conditions (15 and 25 °C) were used to clarify the combined effects of those two factors on life history traits. A survival rate of more than 70% was observed at the two medium FCs at 15 °C, although survival was <42% at all six of the other food–temperature combinations. Post‐embryonic development times to adult stage in males and females were affected by both FC and temperature; median development times ranged from 28.7 to 37.3 and 31.4 to 35.0 days at 15 °C and 13.7 to 23.9 and 14.3 to 27.7 days at 25 °C, respectively, for males and females. An interaction between the two experimental factors was found only for females, with food shortage being most acute at 25 °C. Clutch sizes also increased with FC at both temperatures and interaction occurred between those two factors. Egg production rates increased with increasing FC similarly at both temperatures without an interaction effect. Adult body size increased with increasing FC at both temperatures: for example, average female prosome length increased from 0.865 mm to 0.922 mm at 15 °C and from 0.799 mm to 0.904 mm at 25 °C. Somatic and population growth rates calculated from the experimental data increased with FC, but the increase was more important at 25 °C. These responses to FC and temperature suggest that both growth and population dynamics of this copepod might be more influenced by food shortage at temperatures >15 °C. Adult body sizes under food‐limited conditions in this study are at the lower end of the range of those observed in situ, while those predicted from in situ temperatures, assuming non‐limiting food conditions, were always larger than those of natural populations. Therefore, food shortage appears to be the most important factor affecting both growth and reproduction of E. japonicus in Lake Biwa.