“It must be because of the orchestra,” said Rio. “That’s where I grew up. My mum . . . my mum was a violinist—is a violinist. M-m-maybe that’s why. I just hear things differently.”

That was the most logical explanation—the fact that he’d grown up around musicians—but something else nudged against his rib cage. Something that didn’t really make sense. Because he had the strangest sensation that he’d been born for this. Just as his mom had been born for the orchestra or Marina had been born for the ocean. Apparently, and for a reason he couldn’t yet understand, Rio had been born to hear gray whales.

Wordlessly, Birch disappeared back into the cabin before returning to the deck. He held out a familiar black T-shirt. On the front was a picture of a gray whale and the silvery handstitched lettering of “Spyhopper Whale-Watching Tours.”

“Welcome to the Spyhopper crew,” Birch said, offering Rio the T-shirt. “That is, if you would like to join us? We could do with an extra pair of eyes and ears to help us.”

“But . . . I’m only here for another three weeks and then I’m going home.”

“It doesn’t matter,” Birch replied. “Someone with your talent will be priceless in helping us count the whales.”

“Please say yes, Rio!” Marina urged. “With your help, just think how many more whales we can save!”

“Save? What do you mean?” Rio asked. “Humans don’t hunt them as much anymore, do they?”

“They don’t,” said Birch. “But unfortunately, we’re still hurting them in numerous other ways.”

“So much plastic ends up in the bellies of whales and dolphins.” Marina shook her head angrily. “Most of the time, they think it’s food.”

“It’s not just the plastic,” Birch added. “The data collected from the Happywhale website helps scientists monitor how rising temperatures are also affecting the gray whales eating habits and behavior.”

Plastic pollution along with climate change was something Rio had studied at school. But sitting in a chilly London classroom looking at photos on the internet was a long way from being on a boat in the actual Pacific Ocean.

He gulped. “What do the rising temperatures mean for them?”

Marina took a long, steady look at him before answering. “It means they’re dying.”

“Dying?”

“And it’s okay for us humans because we can just get out of the water anytime we want.” Marina jabbed her arm in the air. “But the whales can’t. Neither can the turtles, the seals, the walruses, the sea lions, or the dolphins. They’re stuck with it.”

Birch rested a gentle hand on her shoulder. “My daughter, as you can see, is very passionate on this subject. And rightly so.”

“That’s why I studied so hard for my science exams,” she said proudly. “Because I want to be a marine biologist when I’m older. I want to help save the ocean! But until then, I’m doing what I can. By counting one whale at a time.”

“The more data we collect,” said Birch, “the more we help raise awareness of what’s happening in the ocean. And awareness is the heart of change.”