Vitamin B1 (hereafter thiamine) is an essential nutrient required by all living organisms as an essential coenzyme in both anabolic and catabolic carbon metabolism. Yet despite being necessary for all life, very few organisms can synthesize thiamine de novo, and most trophic levels in freshwater food webs obtain it through diet. Thiamine deficiency in animals causes crippling morbidities and neurological disorders and has triggered large population declines in wildlife species globally, especially in fishes. Thiamine deficiency has been most widely diagnosed and studied within populations of anadromous salmonids in the Laurentian Great Lakes, the Baltic Sea, and the New York Finger Lakes, and most recently in the Pacific northwest of the United States. Here we discuss the emerging threat of thiamine deficiency in non-salmonids in freshwaters with particular attention on the white sturgeon (Acipenser transmontanus), a long-lived, slow growing species of concern native to the Pacific northwest, whose populations have seen significant declines of young-of-the-year retention in the Columbia River Basin. In 2023 and 2024 we measured sturgeon egg thiamine and related it to very early rearing morality of white sturgeon larvae within the Yakama Nation Fisheries hatchery program. We will discuss how to diagnose thiamine deficiency in species without known egg thiamine thresholds and broadly explore the ecosystem shifts that may be leading to thiamine deficiency across species and global ecosystems.