There are 21 independent coho populations within the Oregon Coast (OC) coho salmon evolutionarily significant unit (ESU). The OC coho ESU is listed as “threatened” under the federal Endangered Species Act (ESA). The listing is due primarily – though not entirely – to habitat loss, and uncertainty concerning trends in freshwater and estuarine habitat quality. Section 3.2 of the federal recovery plan states….
Many human activities contributed to the original ESA listing of Oregon Coast coho salmon as a threatened species. In 1998, NMFS determined: “For coho salmon populations in Oregon, the present depressed condition is the result of several longstanding, human-induced factors (e.g., habitat degradation, water diversions, harvest, and artificial propagation) that serve to exacerbate the adverse effects of natural environmental variability from such factors as drought, floods, and poor ocean conditions (NMFS 1998).” A subsequent status review in 2005 by NMFS’ BRT found that risks posed by hatchery fish and fisheries had been greatly remedied, but questioned whether the ESU’s deteriorated freshwater habitat was capable of supporting levels of coho productivity needed to sustain the species during periods of poor ocean conditions (Good et al. 2005). Subsequent status reviews conducted in 2011 and 2015 found continued uncertainty about ESU status because of persisting threats potentially driving its long-term status (habitat degradation and climate change) that were predicted to degrade in the future (Stout et al. 2012; NWFSC 2015).
There are 7 independent coho populations in the state of Oregon within the Southern Oregon Northern California Coast (SONCC) coho ESU. The combined effects of fish harvest, hatcheries, hydropower operations, and habitat alterations caused by land management led to declines in these populations. The National Marine Fisheries Service’s (NMFS) evaluation of declining coho salmon abundance and productivity, as well as range reductions and diminished life-history diversity, supported the decision to list the SONCC ESU as a threatened species under the ESA in 1997, a decision that was reaffirmed in 2005. Section 1.4 of the federal recovery plan states…..
The decision to list the SONCC coho salmon ESU was largely based on information regarding decreased abundance, reduced distribution, and degraded habitat. There are far fewer streams and rivers supporting coho salmon in this ESU now compared to historical conditions, and numerous basin-specific extirpations of coho salmon have been documented (Brown et al. 1994, NMFS 1996, CDFG 2004a, Good et al. 2005, Gustafson et al. 2007). At the time of listing, the major factors in the decline of the species were thought to originate from long-standing, human induced actions (e.g., habitat degradation, harvest, water diversions, and artificial propagation), combined with natural environmental variability (62 FR 24588, May 6, 1997).
Numerous local, state, and federal policies and regulations govern the conservation of habitats that are essential to coho. Examples include the management of habitats and protection of water quality on forest and agricultural lands, development of floodplains, management of beaver, management of rural-residential development, regulation of instream gravel removal etc. Since before the initial ESA listing, the state of Oregon has relied heavily on voluntary stewardship of working and residential lands as a tool to recover coast coho. Today the state stands as a national leader in creating and maintaining a model of governance that provides the financial, technical, and social capacity necessary for landowners to drive a voluntary statewide recovery effort.
Despite this, NMFS final listing determination for Oregon Coast coho salmon in 2011 stated, “We remain concerned that regulation of some habitat altering actions is insufficient to provide habitat conditions that support a viable ESU.” The OC Coho Recovery Plan explained:
Regarding spawning and rearing habitat (including estuaries), however, the state of Oregon and numerous stakeholders prefer reliance on voluntary actions, not regulatory mechanisms, to protect the environment and achieve coho salmon recovery goals. These volunteer efforts are vital to habitat restoration efforts, but may not be enough to achieve long-term coho salmon recovery without additional regulatory protection. The question NMFS must consider, therefore, is if the combination of voluntary measures and regulatory mechanisms is adequate to ensure the long-term health of Oregon Coast coho salmon habitat.
While NMFS is encouraged by the multiple voluntary and regulatory revisions by state, federal, and non-governmental organizations, as our 2016 5-Year Review (NMFS 2016c) states “at this time we do not have information that would reveal improvements in (ESU-wide) habitat quality, quantity, and function.” Consequently, we remain concerned about the adequacy of existing voluntary and regulatory mechanisms to stop habitat conditions from further decline in the future.”
While the Coast Coho Partnership is focused on accelerating the voluntary restoration of watersheds and not on species management and land use regulation, these issues play an important role in the value of watershed restoration. If current policies are insufficient to protect existing watershed function than restoration will not be able to provide the net benefit intended. In fact, in this scenario it will only serve to offset (subsidize) the adverse impacts of ongoing management and regulatory deficiencies. It is imperative, therefore, that sufficient regulatory certainty exists to safeguard watershed function, so the cumulative benefits of voluntary restoration actions coast-wide can be realized and lead to species’ recovery.