Resource managers should consider the law of “limiting factors” if they have any hope of saving the imperiled delta smelt It’s not lost on those concerned with the environmental health of the Sacramento-San Joaquin Delta and adjacent upper San Francisco Estuary that efforts to reverse declines of its imperiled fishes are failing. All the region’s fishes that are protected under the federal Endangered Species Act appear to have suffered reductions, some dramatic reductions, in abundance over the past two decades. The failure to respond to a native fishery in crisis falls in substantive part on the collective shoulders of the well-funded scientific community. From long-term surveys incapable of accurately monitoring the status and trends in numbers of those imperiled fishes to laboratory studies that can’t possibly mimic in-situ estuary conditions, […] Written by Dennis D. Murphy April 11, 2021April 12, 2021
Whither habitat for the imperiled delta smelt? Conservation science has offered one widely appreciated truism above all others. Habitat loss and fragmentation is the primary cause of imperilment and extinction for very many species. This is certainly the case for the delta smelt, which has seen its habitat diminished and transformed by human activities dating back to California’s gold rush era. Congress recognized the importance of habitat when it enacted the federal Endangered Species Act nearly five decades ago, declaring as its purpose — “to provide a means whereby the ecosystems upon which endangered species and threatened species depend may be conserved” — in other words, to protect and restore the habitats that support imperiled species. The […] Written by Dennis D. Murphy February 5, 2021February 6, 2021
A new understanding of the status of longfin smelt and its conservation needs Late last year the State Water Contractors hosted a first-ever Longfin Smelt Science Symposium on in Sacramento. The meeting featured and was attended by all researchers with first-hand and on-the-water experiences with the species in a forum that addressed both its ecology and genetics. Information emerged that has direct and immediate application in the conservation of the fish. The longfin smelt was listed as threatened by the State of California in 2009. The then Department of Fish and Game in its status review of the species, noted spare survey data and anecdotal records of the species across its coastal range from Alaska to just south of San Francisco Bay. The […] Written by Dennis D. Murphy October 29, 2020December 3, 2020
