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Lake Pend Oreille and the Clark Fork River provide essential ecosystem services, including fisheries and hydroelectric power, to residents of Montana, Idaho, and Washington. Although conflicts exist, these services are maintained in concert by emergent sociocultural services created by a multi-institutional, transboundary collaboration. This has been enabled by an innovative Federal Energy Regulatory Commission license settlement agreement among a multitude of stakeholders. The consensus-based agreement promotes connections among people, projects, waterways, and fish populations. Collaborative management efforts allow stakeholders to address controversial issues, such as invasive fish suppression. We demonstrate how reciprocal cultural ecosystem services and services to ecosystems can enable ecosystem-scale restoration that addresses invasive species, habitat protection, and water quality management. Continued ecosystem management success relies on sustaining the relationship-building and shared knowledge services that have emerged over the past 25 years.

Salmon provide an important resource subsidy and linkage between marine and land-based ecosystems. This flow of energy and nutrients is not unidirectional (i.e., upstream only); in addition to passive nutrient export via stream flow, juvenile emigrants actively export nutrients from freshwater environments. In some cases, nutrient export can exceed import. We evaluated nutrient fluxes in streams across central Idaho, USA, using Chinook salmon (Oncorhynchus tshawytscha) adult escapement and juvenile production data from 1998 to 2008. We found in the majority of stream-years evaluated, adults imported more nutrients than progeny exported; however, in 3% of the years, juveniles exported more nutrients than their parents imported. On average, juvenile emigrants exported 22% ± 3% of the nitrogen and 30% ± 4% of the phosphorus their parents imported. This relationship was density-dependent and nonlinear; during periods of low adult abundance, juveniles were larger and exported up to 194% and 268% of parental nitrogen and phosphorus inputs, respectively. We highlight minimum escapement thresholds that appear to (i) maintain consistently positive net nutrient flux and (ii) reduce the average proportional rate of export across study streams. Our results suggest a state shift occurs when adult spawner abundance falls below a threshold to a point where the probability of juvenile nutrient exports exceeding adult imports becomes increasingly likely.

Seals (Phocidae) are known predators of Atlantic Salmon Salmo salar from their entry into the estuary as smolts until their return to freshwater as adults. We developed a written protocol for identifying seal‐induced injuries on adult Atlantic Salmon returning to Maine rivers. The protocol, which includes photos and category definitions, has been used since 2006 by Maine Department of Marine Resources biologists when handling adult Atlantic Salmon at the Veazie Dam fishway on the Penobscot River and at other adult capture facilities in Maine. The written protocol has ensured that reporting is consistent among years and rivers; photos of wounds serve as quality assurance for the protocol. For adults returning to the Penobscot River in 2006 and 2007, seal‐induced injuries were more likely to be found on two‐sea‐winter fish; to appear as gashes or arched wounds; to be open rather than healed; and to occur on the center third of the body below the lateral line. Larger two‐sea‐winter fish (>67 cm FL) returning to the Penobscot River early in the run (May–early July) were more likely to have a seal‐induced injury. Injury rates increased from 1978 to 2010; this increase was correlated with seal aerial counts for the Gulf of Maine and Penobscot Bay. From 2006 to 2010, the annual seal‐induced injury rate for Atlantic Salmon in six Maine rivers (including the Penobscot River) ranged from 0.00 to 0.30 across rivers. Rates of injury on Atlantic Salmon for all years combined did not differ among the six rivers, but low power likely affected our ability to detect any differences. Received July 25, 2013; accepted February 5, 2014

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