Sandy beach surf zones serve as alternative nursery habitats for juvenile Chinook salmon (0 age) during their early marine residency, a period considered critical due to high and variable mortality rates. Despite the importance of early marine residence, the extent of juvenile salmon surf zone use and movement along sandy...
We evaluated the relative importance of "bottom-up" (production-limited) and "top-down" (predator-mediated) processes during early marine residence in a population of Chinook salmon (Oncorhynchus tshawytscha) from the upper Columbia River, USA. We examined length, mass, and condition index of age-0 juveniles collected in the ocean during June and September across 11...
The community of trophically transmitted marine parasites of juvenile coho (Oncorhynchus kisutch) and Chinook
(Oncorhynchus tshawytscha) salmon across 8 years (2002–2009) was related to indices of physical and biological ocean conditions
and adult returns. When the biomass of lipid-poor, southern origin copepods in the coastal ocean was high during juvenile...
We examined 1454 juvenile Chinook salmon, Oncorhynchus tshawytscha (Walbaum), captured in nearshore waters off the coasts of Washington and Oregon (USA) from 1999 to 2004 for infection by Renibacterium salmoninarum, Nanophyetus salmincola Chapin and skin metacercariae. The prevalence and intensities for each of these infections were established for both yearling...
The dynamic Quaternary geology of the Pacific Ring of Fire created substantial challenges for biogeography. Fish life history and population genetic variation were shaped by climate change, repeated formation and subsidence of ice sheets, sea-level change, volcanism and tectonics, isostatic rebound, and now human activities. It is widely recognized in...
The Columbia River Basin historically supported abundant populations of Pacific salmon (Oncorhynchus spp.) but, largely due to anthropogenic influence, many populations are now listed as threatened or endangered under the U.S. Endangered Species Act. Habitat restoration efforts have been a critical component of salmon recovery plans. However, although the importance...
As highlighted in this study, shallow-water habitats and the prey they provide are important for juvenile salmon in the Columbia River estuary, but the spread of invasive species and large-scale changes to the estuary influence how these habitats are utilized. Reed canarygrass (Phalaris arundinacea) (“PHAR” hereafter) is a highly invasive...
Recent research conducted throughout the Northern California Current (NCC) on the ecology of Pacific salmon (Oncorhynchus spp.) indicates that variable ocean conditions affect the community composition of zooplankton in the nearshore environment which, in turn, can affect the quality of prey for fish, sea birds and mammals. Interannual variability in...
This project, to propose an implementation strategy for standard monitoring
protocols, builds on my Pacific Northwest National Laboratory Fellowship to support a
study entitled Evaluating Cumulative Ecosystem Response to Restoration Projects in the
Columbia River Estuary (Diefenderfer et al. 2005). The major objective of the study was
to develop a...
Full Text:
associated equations used to assess salmonid survival.
Teel, D.J., G.B. Milner, G.A. Winans, and W.S
Early life stages of many marine and diadromous fish species use sandy beach surf zones, which occur along >50% of the world's marine coastlines. This extensive habitat can provide juvenile fishes with an abundant supply of potential prey and the ability to hide from predators in its shallow turbid waters....