Tag Archives: cod populations
Cod Populations Might be Losing a Migration ‘Supergene’
North Atlantic cod populations haven’t just decreased in number during the last century — their genetic diversity has plunged, too, which could ultimately impede cod from traveling long distances, according to a new study published in the June 26 issue of Science Advances. In particular, overfishing, climate change or a combination of factors may have led to the loss of a closely-linked group of genes — a “supergene” — associated with migratory behavior. Absence of this supergene may interfere with the cod’s ecological niche and could make populations more vulnerable to future collapse. Researchers investigated genetic variation in Northern cod around the Canadian province of Newfoundl,,, >click to read<15:23
Pacific Ocean ‘blob’ appears to take toll on Alaska cod
Gulf of Alaska cod populations appear to have nose-dived, a collapse fishery scientists believe is linked to warm water temperatures known as “the blob” that peaked in 2015. The decline is expected to substantially reduce the Gulf cod harvests that in recent years have been worth — before processing — more than $50 million to Northwest and Alaska fishermen who catch them with nets, pot traps and baited hooks set along the sea bottom.,,, Scientists don’t ascribe the blob specifically to climate change. Gulf of Alaska temperatures — influenced by atmospheric conditions such as wind strengths — have always fluctuated over time. But researchers have never before tracked such an extreme heat wave that spread across such distances and penetrated to such depths. click here to read the story 11:52
