Steve Ringman/The Seattle Times

Suburban development is forcing some songbirds to divorce, pack up and leave and miss their best chances for successful reproduction.

As forested areas increasingly are converted to suburbs, birds that live on the edge of our urban footprint must find new places to build their nests, breed and raise fledglings. New research published Dec. 28 in the journal PLOS ONE finds that for one group of songbirds — called “avoiders” — urban sprawl is kicking them out of their territory, forcing divorce and stunting their ability to find new mates and reproduce successfully, even after relocating.

“The hidden cost of suburban development for these birds is that we force them to do things that natural selection wouldn’t have them do otherwise,” said lead author John Marzluff, a professor of wildlife science in the University of Washington’s School of Environmental and Forest Sciences.

“Because development requires that these birds move, we force them to abandon the places they selected and go elsewhere, which often entails finding new mates when they wouldn’t have otherwise.”

Avoider birds are species that are known to decline in response to urbanization, for example when forested areas are removed for developments. In the Pacific Northwest, two avoiders are the Pacific wren and Swainson’s thrush — birds that are generally shy of humans and rely on groundcover and brush such as fallen trees, root balls, shrubs and ferns for breeding.

This work was also written about in The Seattle Times on December 28, 2016. Read “Birds in the suburbs: Faced with urbanization, some beloved species thrive, some move out“.

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Climate Central

A University of Washington oceanographer is chief scientist on a voyage in the waters around Antarctica as part of a major effort to monitor the Southern Ocean.

Stephen Riser, a UW professor of oceanography, embarked Dec. 24 as part of the Southern Ocean Carbon and Climate Observations and Modeling, or SOCCOM, project to collect better data about the planet’s most remote ocean.

The expedition is two-thirds of the way through a monthlong voyage from Punta Arenas in southern Chile to McMurdo Station in Antarctica. Along the way, researchers are deploying robotic floats built at the UW as part of the six-year, $21 million National Science Foundation effort. The multi-institutional project, based at Princeton University, will gather detailed observations of the Southern Ocean to understand its role in the global climate.

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(NOAA)

Eelgrass, a marine plant crucial to the success of migrating juvenile salmon and spawning Pacific herring, is stable and flourishing in Puget Sound — despite a doubling of the region’s human population and significant shoreline development over the past several decades.

That finding surprised scientists who study eelgrass, which sprouts in the brackish waters close to shore and provides shelter and breeding habitat for fish and invertebrates. Along many beaches in Puget Sound, eelgrass has disappeared or drastically declined due to factors such as warmer, cloudy water, shoreline armoring and structures like piers and docks that block sunlight.

The new findings, published online in November in the Journal of Ecology, draw on a unique 41-year dataset to show that the eelgrass population is doing well across the Puget Sound basin. That means eelgrass die-offs at individual beaches are not pervasive enough to affect the overall population across the region.

“Our human population has exploded; we have all kinds of increasing impacts on Puget Sound, and yet eelgrass is resilient,” said co-author Phil Levin, a University of Washington professor of practice and lead scientist at The Nature Conservancy. “It gives us hope about the ability to restore eelgrass. It tells us that what we do at the neighborhood scale matters, and we can have a positive impact.”

The study’s authors were able to analyze trends in eelgrass population over 41 years — the longest period ever recorded for this species in Puget Sound — by making use of shelved data that recorded more than 160,000 eelgrass observations dating back to the early 1970s.

The Seattle Times also wrote about this research on January 3, 2017. Read “A bright spot in Puget Sound: Sealife-nurturing eelgrass beds are holding steady“.

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Jay Johnson/University of Wisconsin

The global climate is a complex machine in which some pieces are separate, yet others are connected. Scientists try to discover the connections to predict what will happen to our climate, especially in a future with more heat-trapping gases.

A dramatic pattern in our planet’s climate history involves paroxysms in Arctic temperatures. During the last ice age, tens of thousands of years ago, Greenland repeatedly warmed by about 10 degrees Celsius over just a few decades and then gradually cooled. Meanwhile the Southern Hemisphere climate stayed fairly stable, with only weak and long-delayed echoes of the temperature chaos up north.

But new University of Washington research shows the fierce winds circling Antarctica — an important lever on the global climate — shifted quickly in response to the Northern Hemisphere temperature spikes.

“It’s most surprising that we can see these really abrupt changes in the Northern Hemisphere making it very quickly to the Southern Hemisphere,” said first author Bradley Markle, a UW doctoral student in Earth and space sciences. “The atmospheric circulation is tightly connected across the globe during these events.”

The study is published in the January issue of Nature Geoscience.

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jkirkhart35/Flickr

The ocean acidification expected as seawater absorbs increasing amounts of carbon dioxide from the atmosphere will reverberate through the West Coast’s marine food web, but not necessarily in the ways you might expect, new research shows.

Dungeness crabs, for example, will likely suffer as their food sources decline. Dungeness crab fisheries, valued at about $220 million annually, may face a strong downturn over the next 50 years, according to research published today in the journal Global Change Biology. But pteropods and copepods, tiny marine organisms with shells that are vulnerable to acidification, will likely experience only a slight overall decline because they are prolific enough to offset much of the impact, the study found.

Marine mammals and seabirds are less likely to be affected by ocean acidification, the study found.

“This was basically a vulnerability assessment to sharpen our view of where the effects are likely to be the greatest and what we should be most concerned about in terms of how the system will respond,” said Tim Essington, a UW professor of aquatic and fishery sciences and a co-author of the research.

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Eva Stüeken

Conditions suitable to support complex life may have developed in Earth’s oceans — and then faded — more than a billion years before life truly took hold, a new University of Washington-led study has found.

The findings, based on using the element selenium as a tool to measure oxygen in the distant past, may also benefit the search for signs of life beyond Earth.

In a paper published Jan. 18 in the Proceedings of the National Academy of Sciences, lead author Michael Kipp, a UW doctoral student in the UW’s Department of Earth and Space Sciences, analyzed isotopic ratios of the element selenium in sedimentary rocks to measure the presence of oxygen in Earth’s atmosphere between 2 and 2.4 billion years ago.

Kipp’s UW coauthors are former Earth and space sciences postdoctoral researcher Eva Stüeken — now a faculty member at the University of St. Andrews in Scotland — and professor Roger Buick, who is also a faculty member with the UW Astrobiology Program. Their other coauthor is Andrey Bekker of the University of California, Riverside, whose original hypothesis this work helps confirm, the researchers said.

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