New research on Alaskan fishing communities shows the crucial importance of fishing portfolios and turnover. In 1989, when there were both major ocean and market regime shifts, most communities lost fishing revenue. But those with the greatest diversity of fished species, and those that were most able to switch from one group of species to another, had little lost revenue, or even experienced increased revenue. 

Animal populations are endangered when they face multiple human-caused pressures at the same time, especially if those pressures interact to worsen depletion. A new study shows that whether pressures interact to worsen overall pressure, or interact to reduce overall pressure, depends on how animal populations behave at low versus high densities. If the number of offspring that survive for each adult drops off slowly as populations increase, this can unexpectedly lead to trouble, since it is more likely that individual pressures will interact to make things worse. 

A major component of fisheries management is using highly complex computer models to figure out the highest catch that can be taken from a fish population—the so-called Maximum Sustainable Yield, or MSY. A critical assumption underlying MSY estimates is how to model the relation between total amount of spawning fish and the resulting offspring that they produce. A new paper by SAFS director André Punt and NOAA researcher Jason Cope examines a wide range of these models to find the best three-parameter version that can independently estimate both the amount of spawning fish and the fishing harvest rate that will produce MSY, concluding that the Ricker-Power model is the best. 

A new review of the contribution of genomics to seafood management reveals how new questions may be addressed by genetics. Genomics involves sequencing the complete DNA of organisms, which has a great variety of applications, including greatly enhancing our ability to define management units, tracing whether seafood is being labelled correctly when sold, identifying how often salmon stray from their streams of origin, detecting seafood diseases, and measuring the extent of fisheries-induced evolution. 

There is potential to increase ocean catches by 14% and ocean profits from fishing by 79%, by rebuilding overfished stocks, fishing more on under-fished populations, and improving fisheries with little effective management. The new research was published in Marine Policy by SAFS professor Ray Hilborn and UCSB professor Christopher Costello. 

A new study looks at clams and mussels in five estuaries in Puget Sound, and finds that alterations to river flow, landscape connectivity among adjacent habitat types, or the type and supply of suspended organic matter (detritus), can disrupt food webs at the scale of entire landscapes. Clams and mussels, which cannot move to track food sources, are particularly affected by climate variability, levee systems, water diversion from estuaries, and dwindling availability of detritus due to loss of tidal marsh wetlands. 

A new paper in Ecological Indicators by Hannah Linder and SAFS professor John Horne examines a wide range of statistical methods for detecting and forecasting change from monitoring studies. They found that different classes of models are needed to detect change, and to forecast the future effects of interventions such as building marine tidal turbines. 

Fishing can substantially alter when fish migrate and when they breed, says a new review in Fish and Fisheries by SAFS student Michael Tillotson and faculty member Thomas Quinn. For example, fishing closures may increase fishing on late breeders, resulting in a greater proportion of early breeders in the population. Such changes can exacerbate the effects of climate-driven changes in the timing of migration and breeding. 

UW Today featured SAFS professor Ted Pietsch, who co-authored a new report documenting all the fishes in the Salish Sea, from the familiar coho salmon to the intriguing dwarf wrymouth. 

A new article, titled “Conservation challenges of predator recovery”, has been accepted for publication into Conservation Letters: A journal for the Society for Conservation Biology.  This article is a result of the collaboration of SAFS post-doc Kristin Marshall, SMEA Professor Ryan Kelly, NOAA scientist and SAFS affiliate faculty Eric Ward, and NOAA scientists Jameal Samhouri and Adrian Stier.
Abstract
Predators are critical components of ecosystems.