fish decline – Page 4 – Desdemona Despair

Overall state of all natural World Heritage sites in 2014, 2017, and 2020. Graphic: IUCN

December 7, 2020

Climate change now top threat to natural World Heritage sites – Great Barrier Reef declines to “critical” status

GLAND, SWITZERLAND, 2 December 2020 (IUCN) – Climate change is now the biggest threat to natural World Heritage, according to a report [pdf] published today by IUCN (International Union for Conservation of Nature). A third (33%) of natural World Heritage sites are threatened by climate change, including the world’s largest coral reef, the Great Barrier […]

Environmental relevance of 6PPD-quinone. (A) Using retrospective UPLC-HRMS analysis of archived sample extracts, 6PPD-quinone was quantified in roadway runoff and runoff-impacted receiving waters. Each symbol corresponds to duplicate or triplicate samples, boxes represent first and third quartiles. For comparison, the 0.8 pg/L LC50 value for juvenile coho salmon and detected 6PPD-quinone levels in 250 and 1000 mg/L TWP leachate are included. (B) Predicted ranges of potential 6PPD-quinone mass formation in passenger cars (e.g., 4 tires, -36 kg tire rubber mass) and heavy trucks, (e.g., 18 tires, -900 kg of tire rubber) (represented in orange) and measured 6PPD-quinone concentrations in affected environmental compartments (represented in blue, with experimental data italicized). Predicted ranges reflect calculations applying 0.4-2% 6PPD per total vehicle tire rubber mass followed by various yield scenarios (1-75% ultimate yields) for 6PPD reaction with ground-level ozone to form 6PPD-quinone. Graphic: Tian, et al. / Science

December 4, 2020

Tire dust killing coho salmon returning to Puget Sound, new research shows – “I find it incredibly sad to watch the adults when they are sick”

By Lynda V. Mapes 3 December 2020 (Seattle Times) – First they circle. Then they gasp at the surface of the water. Soon they can’t swim. Then they die. For decades now, scientists have known something was killing beautiful, adult coho salmon as soon as they hit Seattle’s urban waters, ready to spawn. They had […]

An Ecuadorian navy officer looks at a radar after a fishing fleet of mostly Chinese-flagged ships was detected in an international corridor that borders the Galapagos Islands' exclusive economic zone, in the Pacific Ocean, on 7 August 2020. Photo: Santiago Arcos / Reuters

August 9, 2020

Ecuador navy surveils huge Chinese fishing fleet near Galapagos Marine Reserve

By Santiago Arcos 9 August 2020 ABOARD ECUADOREAN NAVY AIRCRAFT (Reuters) – Ecuador’s navy is conducting surveillance of a massive Chinese fishing fleet that is operating near the protected waters of the Galapagos Islands, amid concerns about the environmental impact of fishing in the area of the ecologically sensitive islands. The navy conducted a patrol […]

Aerial view of the Deepwater Horizon oil rig burning after an explosion in the Gulf of Mexico, off the southeast tip of Louisiana, 21 April 2010. Ten years after an oil rig explosion killed 11 workers and unleashed an environmental nightmare in the Gulf of Mexico, companies are drilling into deeper and deeper waters where the payoffs can be huge but the risks are greater than ever. Photo: Gerald Herbert / AP Photo

April 19, 2020

10 years after BP spill: Oil drilled deeper; rules relaxed – “I’m concerned that in the industry, the lessons aren’t fully learned — that we’re tending to backslide”

By Kevin Mcgill and Matthew Brown 18 April 2020 NEW ORLEANS (AP) – Ten years after an oil rig explosion killed 11 workers and unleashed an environmental nightmare in the Gulf of Mexico, companies are drilling into deeper and deeper waters, where the payoffs can be huge but the risks are greater than ever. Industry leaders and […]

Empirical relationship between system area and regime shift duration in freshwater, marine, and terrestrial systems. Graphic: Cooper, et al., 2020 / Nature Communications

March 12, 2020

Ecosystems the size of Amazon rainforest “can collapse within decades”

By Jonathan Watts 10 March 2020 (The Guardian) – Even large ecosystems the size of the Amazon rainforest can collapse in a few decades, according to a study that shows bigger biomes break up relatively faster than small ones. The research reveals that once a tipping point has been passed, breakdowns do not occur gradually […]

The Blue Acceleration: global trends in human exploitation of ocean resources. Graphic: Jouffray, et al., 2020 / One Earth

February 26, 2020

The “blue acceleration”: Study shows humans’ surging incursions into the sea

By Grace Dungey 13 February 2020 (Mongabay) – Humanity has depended on the ocean for millennia. Today, however, the rush to the sea is occurring with unprecedented diversity and intensity, propelled by population growth and demand for diminishing terrestrial resources. A study published in January in the new journal One Earth analyzed 50 years of data on 18 kinds […]

Spatial cumulative extents of the Deepwater Horizon (DWH) oil spill. (A) Cumulative NESDIS anomaly daily composites integrated from 20 April 2010 to 21 July 2010. Daily fishing closures are marked with gray lines; the cumulative fishing closure area is marked with a thick dashed yellow line. The black star represents the location of the DWH blowout. (B) Cumulative value of daily average oil concentrations (ppb), integrated across the same time span as (A) and across water depths. Vertical depth layers are 0 to 1 m, 1 to 20 m, and in 20-m increments down to 2500 m. Sediment and water samples with higher-than-background concentration are marked in bright green and dark blue circles, respectively. Red crosses in (B) represent approximate locations of DWH-related oil detections reported in previous studies. Daily fishery closures are marked with black polygons; the cumulative fishery closure area is marked with a dashed thick polygon. AB, Apalachee Bay; DP, Deep Plume; EFS, East Florida Shelf; FK, Florida Keys; LC, Loop Current System; TXS, Texas Shores; WFS, West Florida Shelf. (C) Categorization of the modeled oil spill are as follows: (i) nontoxic, PAH concentrations above background level and smaller than 0.5 and 1 ppb at the surface (depth, 0 to 1 m) and in the water column (depth, >1 m), respectively; (ii) toxic-to-biota and invisible, PAH concentrations 0.5 to 17 ppb at the surface and above 1 ppb in the water column; and (iii) toxic and visible, PAH concentrations above 17 ppb. In (C), categories were computed according to maximal concentrations across time. (D) Duration of toxic concentrations across the domain. (E) LC50 of 12 experiments examining the photoinduced toxicity to blue crab (31), fiddler crab (33), mahi mahi (29, 30), red drum (32), and speckled sea trout (32) (for more details, see table S2). (F) The spatial extent of the toxic concentrations from (E); color codes in (F) are according to bar colors in (E), representing concentrations exceeding LC50. In (F), toxic PAH of 0.5 ppb was concentrations were considered for surface waters only (depth, 0 to 1 m). Graphic: Berenshtein, et al., 2020 / Science Advances

February 17, 2020

The toxic reach of the Deepwater Horizon oil spill was much larger and deadlier than previous estimates – “Large areas of the Gulf of Mexico were exposed to invisible and toxic oil that extended beyond the boundaries of the satellite footprint and the fishery closures”

By Darryl Fears 12 February 2020 (The Washington Post) – The spread of oil from the Deepwater Horizon disaster in the Gulf of Mexico was far worse than previously believed, new research has found. As the worst offshore oil spill in U.S. history approaches its 10th anniversary in April, a study by two University of Miami researchers […]

Sea surface temperatures off the coast of Tasmania on November 23, 2010-2017. Data: Integrated Marine Observing System (IMOS). Graphic: The Sydney Morning Herald

February 2, 2020

Empty nets and tropical fish in Tasmania as climate change hits Southern Ocean

By Royce Millar and Chris Vedelago 31 January 2020 (The Sydney Morning Herald) – Rising temperatures and climate change have been blamed for the failure of stocks of some of the most popular eating fish in Australia’s Southern Ocean to recover from declines despite more than a decade of protection. The troubling findings come as […]

Dead salmon on the shores of the Ugashik, Alaska in July 2019. More than 100,000 fish in Bristol Bay were killed by heat stress in 2019. Photo: Birch Block

January 19, 2020

Record summer heat in Alaska wiped out at least 100,000 Kuskokwim salmon in Bristol Bay – “I’ve never seen a salmon that is still ocean-bright acting in such a way”

By Isabelle Ross 15 January 2020 DILLINGHAM, Alaska (Alaska Public Media) – The sun beat down relentlessly on Bristol Bay this summer, heating up the rivers and lakes where millions of sockeye salmon returned to spawn. July was the region’s hottest month on record, and in some rivers, that heat was lethal. Tim Sands, an […]

On 1 January 2016 and 2 January 2016, 6,540 common murre carcasses were found washed ashore near Whitter, Alaska, translating into about 8,000 bodies per mile of shoreline — one of the highest beaching rates recorded during the mass mortality event. Photo: David B. Irons

January 17, 2020

Huge “hot blob” in Pacific Ocean caused mass starvation in largest seabird die-off – “The magnitude and scale of this failure has no precedent”

By Michelle Ma 15 January 2020 (UW News) – The common murre is a self-sufficient, resilient bird. Though the seabird must eat about half of its body weight in prey each day, common murres are experts at catching the small “forage fish” they need to survive. Herring, sardines, anchovies and even juvenile salmon are no […]