Advances in Conservation and Management of the Alligator Gar: A Synthesis of Current Knowledge and Introduction to a Special Section

Abstract

Growing appreciation of biodiversity and the role of apex predators, along with the increasing popularity of multispecies and trophy‐oriented angling, has elevated the status of gars—in particular, the Alligator Gar Atractosteus spatula—among anglers and biologists alike. As a result, considerable effort has been spent in recent years to gain a working knowledge of the biology and ecology of the species in order to advance science‐based management. In January 2019, the Alligator Gar Technical Committee of the Southern Division of the American Fisheries Society hosted a symposium entitled “Advances in the Conservation and Management of North American Gars” to showcase the results of research and management efforts conducted throughout the species’ range. Fishery researchers and managers presented a diversity of works, furthering our understanding of population dynamics, stock assessment, genetics, hatchery practices and stocking, habitat use, and angler desires associated with Alligator Gar fisheries. In our introduction to this special section, we introduce these works and provide a synthesis of the current state of scientific knowledge regarding the Alligator Gar. We hope that this will provide context to the works presented in the symposium and will serve to guide the development of future research that addresses the remaining knowledge gaps concerning the species and its growing fishery.

Goodbye to “Rough Fish”: Paradigm Shift in the Conservation of Native Fishes

“…Alligator Gar Atractosteus spatula were once persecuted and reduced to the brink of extinction throughout their native range (Buckmeier et al 2016; Figure 4). However, interest in the species has exploded, especially as a catch‐and‐release opportunity (Smith et al 2020). In Texas, Alligator Gar fishing was unregulated, but increasing popularity in locations like the Trinity River led to implementation of a statewide one fish/day bag limit.…”

Effective number of breeders and reconstructed sibships reveal low reproductive output by a reintroduced population of endangered fish

“…Population persistence of periodic strategists is predicated upon occasional strong recruiting cohorts to support long-lived and highly fecund adult age classes; however, elevated rates of adult mortality and diminished recruitment have increased the extinction risk in these types of fishes (Olden, Hogan & Vander Zanden, 2007;Haxton & Cano, 2016). Management actions are often unable to reverse these populations' declines, largely as a result of limited understanding of factors that affect population growth rates (Hutchings & Reynolds, 2004;Sadovy, 2005;Smith et al, 2020). This is particularly true when reintroducing extirpated populations to modified systems via hatchery augmentation because the reproductive ecology of wild fish in these systems is often unknown and the relative reproductive success of stocked individuals can be difficult to gauge.…”

“…Periodic strategists typically maintain resilience through long lifespans and highly fecund adults that can achieve lifetime reproductive success despite long periods of relatively high offspring mortality (Hixon, Johnson & Sogard, 2014). However, limited or non-existent recruitment and relatively low adult survival may preclude the accumulation of adults necessary to attain population persistence (Rinne & Minckley, 1991;Winemiller, 2005), necessitating augmentation (Duke et al, 1999;Winemiller & Dailey, 2002;Smith et al, 2020). For managers charged with the recovery of periodic strategists, the relative contribution of spawning adults over space and time could arguably be the critical measure in assessing population resilience (Berkeley et al, 2004;Kreiser et al, 2020).…”

Effects of Training on Side-Scan Sonar Use as a Fish Survey Tool: A Case Study of Alligator Gar

“…Alligator gar stocks have experienced a significant increase in recreational fishing pressure across much of their current distribution in recent years. In response, agencies have increased efforts to monitor these fisheries (Smith et al 2020). Population assessment using direct sampling rarely yields numbers sufficient for robust statistical analyses or data trends because catch rates are typically low and variable, even in healthy populations (e.g., 5 fish/hr of gill-net effort; Bodine et al 2015).…”