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Stretching out supplies of fish food to aquaculture species

Some types of aquaculture-raised (farmed) fish and crustaceans rely on wild-caught fish as feed for omega-3 fatty acids and micronutrients. But with the rapid and continuing rise of aquaculture, and the natural limits to the supply of forage fish (anchovies, herring, and their relatives), eventually this supply of feed will be exhausted. A new study now highlights ways in which the supply of fish food can be eked out further by: (1) reducing the proportion of feed that is based on wild-caught fish and switching to crop-based diets such as soy; (2) increasing catches of forage fish to maximum sustainable levels, adding 30% more catch compared to 2012 levels; (3) eliminating the addition of wild-caught feed to non-carnivorous farmed species; (4) eliminating forage fish from pig and poultry diets; (5) using trimmings from the processing of other wild-caught species as food for farmed fish; and (6) increasing the efficiency of farmed fish production. 

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Substantial decline in polar bear range with sea ice loss

Polar bears rely heavily on sea ice to search for prey, and in Baffin Bay between Canada and Greenland, such ice-associated searching halts during ice-free months. However, since 1979, higher temperatures have resulted in the ice-free season in this region increasing by 12 days per decade in this region. Now, satellite-tags placed on 81 polar bears in Baffin Bay reveal that polar bears greatly reduced the area in which they forage between 1991-95 and 2009-15, by as much as 70% in summer. 

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Centennial Story 19: Alexandre N. Zerbini (PhD, 2006)

Alexandre N. Zerbini (PhD, 2006)
It all started on a warm morning in the summer on the beach in my home country of Brazil when I was about 10 years old. I went for a walk with my father and three brothers when we came across a dead dolphin. It was a franciscana (scientifically known as Pontoporia blainvillei), one of the smallest cetaceans, and a species endemic to the western South Atlantic Ocean. 

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Centennial Story 18: Josh London (PhD, 2006)

Josh London

Josh London (PhD, 2006)
The University of Washington seemed like an odd choice for a kid from Tulsa, Oklahoma. However, after a visit to Seattle and the Pacific Northwest, I knew where I wanted to be. And, even though I was initially not accepted, the UW became home for nearly 15 years. And, Seattle has been home for 25 years.
As a freshman, I signed up for the wildlife science program in the College of Forest Resources. 

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Centennial Story 17: Donna Hauser (BS, 2003; MS, 2006; PhD, 2016)

Donna helping with Glenn VanBlaricom’s long term black abalone census project on San Nicholas Island in 2004

Donna Hauser (BS, 2003; MS, 2006; PhD, 2016)
I grew up in Alaska, with wilderness always at my fingertips and primed to study marine biology from my first undergraduate days at UW. Yet the transition to Seattle’s urban environment was challenging until I found a home at SAFS, where professors knew your name, your classmates were your allies, and learning was by experience. 

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Centennial Story 16: Amanda L. Bradford (MS, 2003; PhD, 2011)

Amanda L. Bradford (MS, 2003; PhD, 2011)
I didn’t start off a “dolphin hugger,” as they say in the field of marine mammal science, but rather came to appreciate the unique anatomical, physiological, behavioral, and ecological adaptations of marine mammals while pursuing my BS in Marine Biology at Texas A&M University at Galveston. There, I had an incredible mentor, Dr. Bernd Würsig, who was both world-renowned in this field and extremely supportive of students. 

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Eating oysters and sardines is better for the environment than most land-based food

A new study examines the overall environmental effects of eating different kinds of foods, comparing the energy required, greenhouse-gas emissions produced, release of nutrients harming water quality, and compounds causing acidification; and also looking at freshwater demands, and the use of pesticides and antibiotics. The review examined 148 life cycle analysis documents that cover the complete impacts of each food production source from start to finish. 

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Where did the cod come from?

A new genetic analysis of Pacific cod has identified more than 6000 genetic markers, and demonstrates that their DNA diverges steadily with distance, which is termed “isolation by distance”. The results allow researchers to identify where Pacific cod are caught to within 220 km, even if the unknown Pacific cod come from a population that was not included in the original analysis. 

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Vaccine injection is required to protect sablefish from a common disease in aquaculture

Sablefish is a highly valuable wild-caught fish on the west coast of North America that can also be easily cultured in aquaculture facilities. However, when reared at high densities in pens, disease outbreaks can be a problem, especially a bacteria that causes a disease named furunculosis. A new study examines the effectiveness of a vaccine developed by the company AquaTactics, to test whether this vaccine protects against furunculosis when injected into fish, or when the fish are immersed for one minute in a vaccine solution. 

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How many sensors are needed to cover an area?

Many scientific fields require long-term monitoring of regions using sensors that are fixed in place, such as weather stations or acoustic stations that monitor fish abundance. These sensors produce high-quality streams of data in time, but typically over a small proportion of the study area. A long-standing sampling design problem is calculating how many sensors should be deployed to accurately estimate amounts of monitored variables such as rainfall. 

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