Study projects 55 percent increase in acidity in next 50 years
There’s no stopping ocean acidification without stopping CO2 emissions, and that’s bad news for many marine species, including Dungeness crabs, according to new new research published in the journal Global Change Biology.
Tiny shell-forming organisms like pteropods and copepods are vulnerable to acidification, but will likely experience only a slight overall decline because they are prolific enough to offset much of the impact, the study found. But those impacts will cascade through ocean ecosystems to affect larger animals like crabs, that will suffer as their food sources decline. Dungeness crab fisheries are valued at about $220 million annually, and may face a strong downturn over the next 50 years. Continue reading “Ocean acidification to hit key fisheries”→
New lab experiments suggest that increasing ocean acidification could take a big bite out of the economically important cod fishery in the North Atlantic. The research suggests that the buildup of CO2 in the ocean could double the mortality of newly-hatched cod larvae.
Members of the German research network BIOACID quantified the impacts, showing that recruitment could decrease to levels of one quarter to one twelfth of the recruitment of the last decades. Cod have already been under intense fishing pressure for decades, and the new study, published in the online journal PLOS ONE, identifies climate change as an emerging new threat. Continue reading “Ocean acidification seen as huge threat to Atlantic cod”→
New vulnerability assessment to help guide fisheries management
Rapidly warming ocean temperatures off the coast of the Northeastern U.S. are likely to have a big impact on nearly all fish and other marine life in the region. Scientists with the National Oceanic and Atmospheric Administration carefully surveyed 82 species in a recent study, trying to identify which are the most vulnerable to global warming.
“Our method identifies specific attributes that influence marine fish and invertebrate resilience to the effects of a warming ocean and characterizes risks posed to individual species,” said Jon Hare, a fisheries oceanographer at NOAA Fisheries’ Northeast Fisheries Science Center (NEFSC) and lead author of the study. “This work will help us better account for the effects of warming waters on our fishery species in stock assessments and when developing fishery management measures.” Continue reading “Global warming: Goodbye to sea scallops?”→
Modeling projects huge economic losses in fisheries
A fine-grained look at climate change impacts in Canada suggests that coastal First Nations people might be hit especially hard, with fisheries catch potentially declining by 50 percent in the next few decades. That represents losses between $6.7 and $12 million annually by 2050.
Management not keeping up with changing conditions
The Gulf of Maine is simply getting too warm for cod, fisheries experts said in a new study released this week that links the warming to changes in the position of the Gulf Stream and to climate oscillations in the Atlantic and the Pacific. These factors add to the steady pace of warming caused by global climate change.
Cod stocks, once the mainstay of New England’s fisheries, are on the brink of collapse, hovering at 3 to 4 percent of sustainable levels. Even strict quota limits on fishermen failed to help cod rebound, and that’s unlikely to change any time soon, the researchers reported in the journal Science. Continue reading “New England cod decline linked with warming ocean”→
FRISCO — Nutrient pollution from farming has seeped into nearly every corner of a California estuary, affecting the abundance of fish in the important marine nursery, according to new research by scientists with the University of California at Santa Cruz and The Nature Conservancy.
Lead author Brent Hughes began studying water quality in Elkhorn Slough as a UCSC graduate student. His earlier research showed that virtually every portion of the estuary is adversely affected by high nutrient levels. The pollution stimulates the growth of algae, leading to low oxygen levels when the algae die and decompose.
FRISCO — Melting Arctic sea ice is breaking down the natural barrier between Pacific and Atlantic fish species, with as-yet unknown consequences for ocean ecosystems, scientists said this week in a new study published in Nature Climate Change.