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Hennessey Part 11: Cold Ocean, Warm Sharks

Aug 18 2021

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Original Articles

By Anthony Palumbi and Steven Palumbi

Her pups were not only big, they were also warm. Hennessey’s muscles generated heat with every tail stroke, and then intricate loops in her blood vessels kept the heat inside her, flouting the sucking cold chill of the water. So her pups were constantly bathed in the warmth of her exertions.

But a basic problem existed for large, warm blooded sharks like Hennessey - the shock that would hit them if they were born into frigid water, spit out into the cold uncaring sea. So, she had to find her pups an environment of warm water for their birth - even though the seals she was feeding on only lived in cold water. That created a conflict between what her hunting computer decided – hunt where it is cold -  and what her mother’s brain demanded. Now that her hunting instinct was conquered by food, she could turn back south and find the warm cove her pups required.

South of the hook of rock with the big seals, her brain map remembered the original rookery where the small seals swam. Warmer water, smaller competitors. And nearby there was a string of shallow sandy coves stretching to the south that she could choose among.

It was a short journey for such an ocean sojourner, especially with the metabolic glow of a full stomach – retracing her path along the ocean highways. And so she arrived unerringly at Seal Rocks, expecting to find the small sharks and small seals and warmer water that she’d so recently left.

But instead she returned to a chaotic maelstrom of frenzy.