Few issues in the Delta are as clear cut as predation. Larger predator species eat smaller fish with potential devastating impacts on native endangered species such as salmon and smelt.
Nonnative species pose a particularly significant predation threat in the estuary. Many of these predators were planted in the Delta for sport and recreational fishing purposes, with little concern for the native species they now endanger such as salmon, delta smelt and steelhead.
Exacerbating the problem, it has long been the State’s misguided policy to protect and maintain the populations of these predators through the use of size and bag limits. Fish stocking programs have also been utilized in the past to increase the adult populations of these voracious feeders.
Many species that are nonnative to the Delta have direct or indirect impacts on native threatened species, which greatly reduces survival of native fishes. Striped bass represent a direct predatory threat to the delta smelt and salmon and yet are protected by an ongoing California Department of Fish and Game program that maintains the population at artificially high levels to the detriment of native species. Until 1992, the Department restocked striped bass as part of an active population management program.
- The Coalition filed a lawsuit against the California Department of Fish and Wildlife (DFW) for violating the ESA through its enforcement of State sport fishing regulations. The lawsuit was successfully settled requiring DFW to collaborate with the National Marine Fisheries Service (NMFS) and the U.S. Fish and Wildlife Service (FWS) to develop a joint regulatory proposal addressing the impacts of sport-fishing regulations on listed species. However, the California Fish and Game Commission decline to accept the recommendation at that time.
- Since then, the Coalition has successfully worked with the Commission to update their outdated striped bass policies and institute new Delta Fisheries Management Policies that appropriately prioritize the management of native endangered fish in the Delta.
Washington and Oregon are both home to endangered Columbia River Salmon populations whose conditions have been exacerbated by drought conditions and non-native predator species.
- In 2019 the Washington Department of Fish and Wildlife (WDFW) removed size and bag limits on non-native bass and walleye in the state.
- The decision came in response to legislation aimed at increasing chinook survival in hopes of helping struggling orca populations in the Puget Sound.
- In 2015 the Oregon Department of Fish and Wildlife removed bag limits for warmwater fish (including bass and walleye) in the Columbia, John Day and Umpqua rivers.