Recently, I spent an early April day in the southwestern corner of Cape Cod Bay, in eastern Massachusetts, in the United States, with a friend. He had been at sea his entire working life, but had never knowingly been close to a right whale. His day job was master of an oil tanker on the Valdez, Alaska, to San Francisco, California, run, where he might have been close to a North Pacific right whale ( Eubalaena japonica ). He was vastly overqualified to skipper our boat, which he did while I piloted a small drone to measure the lengths and widths of the many feeding North Atlantic right whales ( Eubalaena glacialis ) we had found in a small area. There was no wind that day. The sea was like a millpond. It was crisp, cold, sunny, and quiet. We shut down the motor, drifted, watched, and listened.

As each animal surfaced, exhaled, and immediately inhaled, we listened to the unique cadence of their breaths, and we watched their steady progress through the water with their mouths wide open, filtering the clouds of food close to the surface. Periodically, they slowly closed on the boat, and we could see into their open mouths, with small eddies of water peeling away from their lips. Much larger eddies formed in their wakes as their powerful tails and bodies pushed them along. They made tight turns, using their huge flippers and tails as rudders, to keep themselves within the food patches. This went on all day. As the sun started to sink behind the cliffs on the nearby western shore of Cape Cod Bay, their creamy white upper jaws, just visible above the surface, turned to a vibrant golden hue. It was a peaceful, majestic, timeless sight, and a huge privilege to be permitted to study these animals. At the end of the day, my friend said that he understood why I care so passionately for them.

Words often fail when I try to express the awe and wonder that these animals elicit; this book is my attempt to do them justice, and keep them out of jeopardy. My hope is to convince you that the welfare of individual North Atlantic right whales, and the very survival of the species, is in our hands. Few humans eat whale meat anymore, but fishing techniques unintentionally harm and kill whales. Even vegetarians contribute to the problem, as we all benefit from global shipping of consumer goods and fuel, which, in its current iteration, leads to fatal collisions with whales. Entanglement in fishing gear can sentence these animals to months of pain and a slow death. Both the US and Canadian governments are stuck in a major conflict of interest: protecting the livelihoods and businesses of the marine transportation and fishing industries, but at the same time recognizing the value of biodiversity, animal welfare, and avoidance of species extinction. Recently, the latter values have taken a back seat. It doesn''t have to be this way.

We have the technology and the collaborations that are necessary to change the right whales'' future, but consumers have to use their wallets to make it happen. Hopefully, politicians still listen to their electorate. Though I will use my personal experiences to make this argument, this book is not a memoir. I use descriptions of my life and work, and that of many, many others, to explain basic principles in marine science and what it would mean to lose this and other species. I also explain how we all can help whales to prosper. This story is, at times, gruesome, but I entreat you to stick with it. Again, I believe we can make it right. The fundamental problem for North Atlantic right whales, as for so many of us, is that they can''t make an adequate living and they struggle to raise a family successfully.

Their carefully evolved energy budget does not work anymore. Right whales'' habit of swimming for many hours at a time with their mouths open to filter food leaves them susceptible to strikes by vessels, and to being entangled in rope wrapped around their heads, flippers, and tails. Whales can be found feeding from the surface to the bottom--wherever the food is. Researchers have spotted them with mud on their heads, a sign that they sometimes come into contact with the ocean bottom. Rope entanglement is one of the leading causes of lethal and sublethal trauma in the North Atlantic right whale. Vertical lines used to mark and retrieve lobster and crab traps are the commonest types of rope in the water column of the Northwest Atlantic Ocean, both in the United States (overwhelmingly lobster) and Canada (lobster and snow crab, primarily). In addition, vessel collisions commonly kill whales. Like most large whale species, right whales lack teeth.

Instead, they have horny plates of a material called baleen suspended from their upper jaws. Some baleen whale species gulp larger prey, while right whales skim their small prey by swimming slowly and steadily. Baleen plates have hairy fringes that make a fine filter, so that right whales can swim through the water with open mouths, sieving through clouds of drifting animals, called zooplankton, that are smaller than rice grains. The water flows out through the baleen, creating endless eddies, while the food is concentrated and swallowed. This is an incredibly efficient way for a very large animal to eat very small ones. These zooplankton, primarily copepods, are oil rich and provide energy for the whales to exist, move, grow, and reproduce. The blubber coats of healthy right whales are full of oil and make the animals buoyant. Rich in oil, slow swimmers, mouths full of valuable baleen, and usually buoyant once they die: these traits made them very early targets for whalers.

Scientists have gleaned this level of detail, from what is essentially a rather cryptic animal, primarily by collecting thousands of photographs of these individually recognizable whales. The photographs are shared with a central database maintained at the New England Aquarium in Boston, Massachusetts, and matched to a catalog of the individuals founded by Scott Kraus and colleagues. Each whale is given a four-digit number. Some are also given a name, usually related to an identifying feature, but occasionally for other reasons. But centuries before we knew them as individuals, thousands were killed for their oil-rich blubber and hugely valuable baleen. In US and Canadian waters, during the 2017-2020 period--just four short years--10 percent of the species has died. In November 2020, the best estimate for the total number of North Atlantic right whales remaining in the species was a mere 356 animals. To solve the problem, we need to have the understanding, commitment, and optimism to carry through with what has to be done--by fundamentally changing fishing and shipping practices.

But we also need to make these changes in ways that are sensitive to the lives of the humans that work in vessels at sea and harvest seafood. Both industries have already borne substantial costs in the name of right whale conservation, with inadequate results. Right whales are a special example of mammals that have evolved to thrive in an unforgiving environment and are specialized in diverse and remarkable ways to exploit specific aquatic resources and environments. We must be the same.