Approaches and research needs for advancing the protection and recovery of imperilled freshwater fishes and mussels in Canada¹

Abstract

Effective conservation requires that species recovery measures are informed by rigorous scientific research. For imperilled freshwater fishes and mussels in Canada, numerous research gaps exist, in part owing to the need for specialized research methods. The Canadian Freshwater Species at Risk Research Network (SARNET) was formed and identified or implemented approaches to address current research gaps, including (1) captive experimental research populations, (2) nonlethal methods for estimating abundance and distribution, (3) nonlethal field methods to measure life-history parameters, (4) species distribution models informed by co-occurring species, (5) conservation physiology to inform habitat and threat science, (6) evidence syntheses to evaluate threats and recovery measures, (7) disease-transmission models to understand mussel–host relationships, (8) experimental mesocosms and manipulative experiments to evaluate key habitat stressors, (9) threat and hazard models for predictive applications, and (10) rigorous evaluation of surrogate species. Over a dozen threat- and recovery-focused SARNET research applications are summarized, demonstrating the value of a coordinated research program between academics and government to advance scientific research on, and to support the recovery of, imperilled freshwater species.

A process framework for integrating stressor-response functions into cumulative effects models

“…As a final recommendation, we ask the researcher to keep the big picture in mind and not get lost in the weeds. It is important to remember that with limited data availability, developing and implementing SR functions for use in a CE modelling framework is a continuous cycle of manipulation and validation (Castañeda et al, 2021). This process takes time.…”

Choosing source populations for conservation reintroductions: lessons from variation in thermal tolerance among populations of the imperilled redside dace1

“…One example of such a CERP (funded by the DFO Canadian Freshwater Species at Risk Research Network; Castañeda et al 2021) is a redside dace population housed at the Freshwater Restoration Ecology Centre, University of Windsor. To date, this CERP consists of individuals (juveniles and adults) collected from parts of the range where the species is not imperilled (i.e., central lineage, captured in Ohio, USA; see Beausoleil et al 2012;Turko et al 2020).…”

Evaluating the Status and Population Biology of an Imperiled Freshwater Mussel, Purple Wartyback (Cyclonaias tuberculata), in Southern Ontario, Canada

“…A better understanding of mussel population ecology is needed to aid recovery planning for at-risk species. Quantifying life-history traits and estimating population size and trajectories are recommended in the recovery strategies for all at-risk mussel species in the Great Lakes basin in Canada (Drake et al 2021), but addressing gaps in our knowledge of population ecology requires prioritizing nonlethal sampling methods to reduce the impacts of research on at-risk species (Castañeda et al 2021).…”