Predicting impacts of chemicals from organisms to ecosystem service delivery: A case study of endocrine disruptor effects on trout

Abstract

We demonstrate how mechanistic modeling can be used to predict whether and how biological responses to chemicals at (sub)organismal levels in model species (i.e., what we typically measure) translate into impacts on ecosystem service delivery (i.e., what we care about). We consider a hypothetical case study of two species of trout, brown trout (Salmo trutta; BT) and greenback cutthroat trout (Oncorhynchus clarkii stomias; GCT). These hypothetical populations live in a high-altitude river system and are exposed to human-derived estrogen (17α‑ethinyl estradiol, EE2), which is the bioactive estrogen in many contraceptives. We use the individual-based model inSTREAM to explore how seasonally varying concentrations of EE2 could influence male spawning and sperm quality. Resulting impacts on trout recruitment and the consequences of such for anglers and for the continued viability of populations of GCT (the state fish of Colorado) are explored. inSTREAM incorporates seasonally varying river flow and temperature, fishing pressure, the influence of EE2 on species-specific demography, and inter-specific competition. The model facilitates quantitative exploration of the relative importance of endocrine disruption and inter-species competition on trout population dynamics. Simulations predicted constant EE2 loading to have more impacts on GCT than BT. However, increasing removal of BT by anglers can enhance the persistence of GCT and offset some of the negative effects of EE2. We demonstrate how models that quantitatively link impacts of chemicals and other stressors on individual survival, growth, and reproduction to consequences for populations and ecosystem service delivery, can be coupled with ecosystem service valuation. The approach facilitates interpretation of toxicity data in an ecological context and gives beneficiaries of ecosystem services a more explicit role in management decisions. Although challenges remain, this type of approach may be particularly helpful for site-specific risk assessments and those in which tradeoffs and synergies among ecosystem services need to be considered.

A Call for Collaboration among Water Quality and Fisheries Professionals

“…) as well as fishes (Forbes et al. ). Because of the fundamentally different approaches of these two groups, each is more likely to work with peers sharing similar educational and professional backgrounds and there is the potential to become narrowly focused.…”

“…Achieving stated goals often occurs through pollutant reduction, implementation of best management practices (e.g., off stream watering for cattle), or improving waterbody form and function (e.g., reconnecting floodplain access), not through the direct manipulation of aquatic organisms. In addition, water quality professionals are concerned with multiple beneficiaries including domestic (e.g., drinking water) and recreational users (e.g., swimmers; Munns et al 2016) as well as fishes (Forbes et al 2019). Because of the fundamentally different approaches of these two groups, each is more likely to work with peers sharing similar educational and professional backgrounds and there is the potential to become narrowly focused.…”

Fisheries Volume 45 Number 3 March 2020

“…Achieving stated goals often occurs through pollutant reduction, implementation of best management practices (e.g., off stream watering for cattle), or improving waterbody form and function (e.g., reconnecting fl oodplain access), not through the direct manipulation of aquatic organisms. In addition, water quality professionals are concerned with multiple benefi ciaries including domestic (e.g., drinking water) and recreational users (e.g., swimmers; Munns et al 2016 ) as well as fi shes (Forbes et al 2019 ). Because of the fundamentally different approaches of these two groups, each is more likely to work with peers sharing similar educational and professional backgrounds and there is the potential to become narrowly focused.…”

Applying ecosystem services for pre‐market environmental risk assessments of regulated stressors

“…In a parallel initiative, Forbes et al. (, ) demonstrated how mechanistic effect models could be used to quantitatively link traditional effects endpoints in ERAs through population‐ and ecosystem‐level responses to impacts on ES delivery. These analyses included an ES valuation step to show how trade‐offs between ES could be compared in a way that could inform management decisions.…”