migration of, 184

as orca food source, 92–93, 111

population stabilisation, 107

in prehistoric seas, 25, 25n

remixing seas and, 35–36

Greenland, 50–52

Grindle, Kim, 245

Guadalupe Island, 134–35

Gulf Stream, 19, 42

Half Moon Caye sanctuary, 216–17

hammerhead sharks, xiii, 82, 90, 102, 105, 106, 107

Harvard University, 259

Hawai’ian Islands, 158, 158n, 213–14

heat waves

author’s personal experience, x–xi

coral reefs and, 205, 208, 210–11, 215, 218–19, 221–23

kelp forests and, 172–73, 186

penguin colony collapses and, 73–74

remixing seas and, 36–37

sea stars and, 187

sharks and, 36, 93

tuna and, 142

Hebridean Whale and Dolphin Trust, 110

Hemingway, Ernest, 138

Henry “Birdie” Bowers, 60–61

Hodin, Jason, 187–89

Hofman, Justin, 240

horse-shoe crabs, 8

hound sharks, 37

Huey, Laurence M., 135

Hugo (orca), 123–24, 124n

human trafficking, 248

Humboldt squid, 36

humpback whales, 51, 72, 145

hybridisation, 221

hydrothermal-vent chimneys, 163–65

ICCAT (International Convention for the Conservation of Atlantic Tunas), 140–41, 140n, 142, 143, 144

ichthyosaurs, 12, 13–14, 16

Indian Ocean

conservation efforts, 166

coral reefs of, 213, 213n, 218

hydrothermal-vent chimneys of, 165

low-lying islands of, 231–33, 233n

in prehistoric era, 20

shark population in, 81

tuna of, 143

Indian Ocean Tuna Commission, 143

Intergovernmental Panel on Climate Change (IPCC), xviii, 219

International Convention for the Conservation of Atlantic Tunas (ICCAT), 140–41, 140n, 142, 143, 144

International Seabed Authority (ISA), 253–56, 254n