Review of a species in peril: what we do not know about lake sturgeon may kill them

Abstract

Lake sturgeon are arguably the largest and most unique freshwater fish in North America. Unfortunately their uniqueness includes many characteristics that make them especially vulnerable to anthropogenic impacts including overfishing, habitat fragmentation, and degradation. For approximately 100 years lake sturgeon populations across North America have either been in decline and (or) have experienced a sluggish recovery. While this is partly due to lake sturgeon life history, most researchers agree that habitat fragmentation and degradation are currently the highest risk to the species. Though most lake sturgeon populations are depressed, there are a few exceptions that offer a glimpse into what a stable population or recovery may look like. The following review highlights such instances as well as what is known and more importantly what is not known about this unique species. Specifically, we highlight the need for improved and organized sharing of raw data given the fact that many researchers do not have access to the plethora of information available to others (e.g., otoliths for aging). We examine the varying life history and diet choices of this plastic species offering hypotheses for differences in migration routes and distances as well the differing recovery rates found across their range. We highlight myths about the species providing evidence that they may not be as long lived and fecund as previously thought. We examine the lake sturgeon’s current legal status across North America including the efforts of nonprofit groups that have had success in increasing population numbers. Most importantly, we highlight logistical problems faced by researchers and data gaps in the literature that must be filled to increase the odds of a successful recovery. Alongside the data gaps, the recovery of this species is fraught with political and industrial road blocks that are as varied as its current recovery. Subsequently, as is the case with many species, its survival will come down to solid scientific knowledge and the value placed on it by society.