Temporal dynamics of freshwater fish assemblages, their background and methods of quantifications—A synthesis

Abstract

The temporal dynamics of biotic communities have been widely examined by ecologists. However, systematic reviews on how habitat features, sampling and data evaluation influence temporal patterns are rather sporadic. Here, we reviewed 307 peer‐reviewed scientific articles to characterize the methods and the approaches, as well as to identify the knowledge gaps in the assessment of the temporal dynamics of freshwater fish assemblages with special regard to their stability patterns. The number of publications increased exponentially over decades. We revealed a highly uneven distribution of the studies among continents and ecosystems with a dominant number of papers derived from North America and Europe, and from lotic systems, especially. We also found large variability among studies even within similar habitat types in the examined spatial and temporal scales, sampling methods used, examined assemblage attributes, potential stressors and data analyses. Several knowledge gaps, such as the limited number of large‐scale studies, the insufficient knowledge on the long‐term dynamics of early life history stages and on trait‐based assemblage organization, were highlighted. For enabling meaningful comparisons of fish assemblage dynamics in space and time, further developments in standardization procedures are needed across sampling and data evaluation possibilities. Publicly accessible long‐term data sets with more details on sampling and environmental parameters would also be critically important to determine the effect of a variety of factors on the stability vs. variability of fish assemblages.

Is it there?—Estimating the invasion of armored sailfin catfish (Pterygoplichthys sp.) in the water bodies of Eastern Ghats, India using the eDNA approach

“…Despite the advantages of eDNA, in detecting taxa, its limitations in areas like streams and rivers should also be considered while designing any study, like eDNA dilution and dispersion, environmental factors influencing eDNA degradation, quantitative challenges in relating eDNA concentration to actual species abundance and accumulation of eDNA from upstream sources leading to false detection in downstream sites. These limitations emphasize the importance of a mixed approach, recognizing the strengths of both traditional and eDNA‐based methods and mitigating the limitations associated with each method (Czeglédi, Sály, et al., 2021; Czeglédi, Specziár, et al., 2021; Eggleton et al., 2010). A study by Jo and Yamanaka (2022) notes that most eDNA particles can travel up to 2 km downstream under normal hydrogeographic conditions.…”

Scale dependency in fish beta diversity–hydrology linkages in lowland rivers

“…We examined how temporal change in fish assemblage composition and hydrologybeta diversity relationships varied among rivers across two spatial extents -the extent of river reaches (<100 km) and the extent of river systems (>1000 km). Our analyses revealed inter-annual changes in fish beta diversity and hydrological-beta diversity relationships differ when assemblages were assessed across short portions of rivers ('reaches') versus across broader extents spanning entire river 'systems' ( Assessing temporal change in the composition of ecological assemblages is fundamental to interpreting trends in biodiversity and biodiversity responses to anthropogenic environmental change (Czeglédi et al, 2022;McGill et al, 2015). We found that patterns of inter-annual change in fish assemblage composition were inconsistent when compared at the extent of reaches versus broader river systems.…”

“…Assessing temporal change in the composition of ecological assemblages is fundamental to interpreting trends in biodiversity and biodiversity responses to anthropogenic environmental change (Czeglédi et al, 2022; McGill et al, 2015). We found that patterns of inter‐annual change in fish assemblage composition were inconsistent when compared at the extent of reaches versus broader river systems.…”

Temporal Changes in Water Quality with Increasing Ambient Temperatures Affect the Distribution and Relative Abundance of 10 Species of Balitorid Fishes in Small Streams of Eastern Thailand

“…Complex interactions further act to alter and destroy aquatic environments (e.g., river temperature, nutrient load, chemical concentration, water volume, and flow adjustment) and their biota, especially sensitive species [10][11][12]. As the interactions between river temperatures and aquatic activities, a little fluctuation in ambient temperature and toxicant concentration can severely impact the physiological response of fish.…”