Detailed analysis of habitat suitability curves for macroinvertebrates and functional feeding groups

Abstract

Environmental flows have primarily a practical purpose, being an important part of water management. Despite the widespread use of environmental flows, current studies rarely describe practical insights of the methods or consider environmental flows based on ecological traits, especially regarding macroinvertebrates. In addition to hydraulic parameters, the ecological traits may also indicate processes that drive the distribution of organisms. Nevertheless, so far the habitat suitability criteria for functional feeding groups, the most commonly used ecological trait for macroinvertebrates, have not been described. In this study, we performed a detailed analysis of habitat suitability curves for the macroinvertebrate community and for FFGs. The criteria were determined based on data collected during two field campaigns (2018 and 2019) from the Flinta River, a lowland, dynamic, sandy stream located in western Poland. The method of habitat preference curves (HPCs) for flow velocities, depths and substrate was adopted. Before determining the final habitat suitability criteria, for all considered groups the habitat preference curves and habitat utilization curves were determined separately for the data collected in 2018 and 2019. The results showed that this step was key in developing the final habitat suitability criteria. Additionally, considering FFGs provided insight into the mechanisms that drove the distribution of organisms and resultant suitability.

Development of an integrated modelling framework to evaluate impacts of pressures on habitat conditions and riverine biota

“…Subsequently, based on the curves for each taxon, we determined proxy curve that represented the preferences of the FFs group towards the flow velocity. The proxy curve was created by analysis of the preference curves for common FFs species in the Jeziorka river and by comparing assumed values with literature data (Leszczyńska et al, 2017; Li et al, 2009; Szałkiewicz et al, 2022). Within the FF group, there are rheophilic taxa (e.g., Hydropsyche sp.)…”

Development of habitat suitability criteria for macroinvertebrate community metrics for use in habitat restoration projects

“…Baetidae, Chironomidae and Hydropsychidae were chosen because they are the dominant taxa present in stomach contents samples of Sacramento River juvenile Chinook Salmon Oncorhynchus tschawytscha (Saiki et al 2001). Diversity and total AFDW, common macroinvertebrate metrics, were selected as indicators of ecosystem health (Szalkiewicz et al 2022;Theodoropoulos et al 2018).…”

“…Choosing curves for individual taxa can be problematic when there are many species with different flow-habitat relationships as it is unclear how to select a single curve. Gore et al (2001), Szalkiewicz et al (2022), and Theodoropoulos et al (2018) developed HSC for macroinvertebrate community diversity, with Gore et al (2001) noting that the evaluation of macroinvertebrate communities is warranted because of the critical role of aquatic invertebrates in the processing of nutrients and organic energy in lotic systems and the increased emphasis on multi-species conservation. Gore et al (2001) found that the bottleneck for fish populations in a North Carolina stream was macroinvertebrate habitat, rather than fish habitat.…”

“…Gore et al (2001) found that the bottleneck for fish populations in a North Carolina stream was macroinvertebrate habitat, rather than fish habitat. Community-based macroinvertebrate HSC are needed for two reasons: (1) community-based criteria, such as with macroinvertebrates, are a better measure of ecosystem health than single-species HSC because they integrate the habitat requirements of multiple species (Szalkiewicz et al 2022;Theodoropoulos et al 2018);and (2) given uncertainty in whether food or physical habitat is the limiting factor for juvenile salmonids, it is advisable to evaluate habitat restoration projects based on both macroinvertebrate and juvenile habitat (Gore et al 2001). More macroinvertebrate habitat can result in higher energy flow potential for juvenile salmon feeding on macroinvertebrates, which can increase growth rates, and thus can result in higher survival when reaching salt water.…”

“…The goal of this study was to generate HSC for macroinvertebrates in the Sacramento River between Keswick Reservoir and Battle Creek. Macroinvertebrates were selected as a measure of food abundance for juvenile salmonids (Gore et al 2001), as well as an indicator of ecosystem health, per Szalkiewicz et al (2022) and Theodoropoulos et al (2018).…”