About

Blue Fathom is a personal reading notebook about Atlantic sea life. It is kept for pleasure and updated rarely. Nothing here is advice for divers, anglers or swimmers.

A fathom is an old unit of depth, six feet or about 1.83 metres.

Sources

• NOAA Fisheries species directory, for size, range and status of whales, turtles, tuna and cod.
• NOAA Ocean Service and Ocean Exploration, for ocean zones, the Sargasso Sea and the Mid-Atlantic Ridge.
• IUCN Red List of Threatened Species, for conservation status.
• Nielsen and colleagues, "Eye lens radiocarbon reveals centuries of longevity in the Greenland shark", Science, 2016.
• Fisheries and Oceans Canada, for the history of the northern cod moratorium.

Corrections

Figures are rounded and some are debated among researchers. Where a number is an estimate, the text says so. The drawings are simple symbols made for this site, not accurate portraits.

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