When I try to convey the immensity of the migratory marvel of marine mammals passing through the Bering Strait—a narrow body of water separating Alaska from the Russian Far East—I can’t help but remember my time in New York City.

Between 2012 and 2014, I frequently made the commute from Queens to the Bronx Zoo, where I was based at the Wildlife Conservation Society, via the New York City subway system. After 25 years of living in Alaska, I was not used to the throngs of people in the Big Apple. At my 52nd Street subway entrance in Queens, I’d join some 7,000 passengers entering onto the 7 train each day.

My 52nd Street cohort was paltry, though, when compared to the crowds farther down the line. Roughly 160,000 commuters pass through the Grand Central Terminal subway stop—the second busiest station in the New York system. In Times Square, the busiest, an estimated 200,000 passengers flood into the fray each day.

To understand the work I’ve been doing in the Arctic, I now ask you to forget these people in the crowded subway and see each commuter not as a dark-clothed New Yorker, but rather as a 40-ton bowhead whale, one of some 18,000 traveling between the Bering Sea and the Arctic Ocean.

And bowhead whales do not travel alone. Joining them are over 100,000 walruses, a few hundred thousand ringed and bearded seals, thousands of beluga whales, more than 10,000 grey whales, and a potpourri of other baleen whales—among them minke, humpback, and fin. In numbers of marine mammals, that’s more than everyone entering at Times Square and Grand Central combined.

The bowhead whales alone are comparable to the biomass of mammals in the world’s greatest terrestrial migration in the Serengeti. There is no getting around the sheer immensity of this movement of marine mammals back and forth through the international waters separating Chukotka in the Russian Federation from Alaska in the United States. If visible on the surface, this would be actually seen as one of the great wonders of our planet.

This “rush hour” of marine mammals passing through Bering Strait is not news in itself. It has taken place for millennia. Local Eskimo villages have hunted marine mammals here for a few thousands of years, primarily due to their reliable ebb and flow from the Arctic with the advance and retreat of the winter sea ice.

The most recent change for this important hub for migratory whales and other marine mammals is the rapidly escalating impact of climate change on sea ice, the backbone of these Arctic ecosystems. Animals and people are now forced to adapt to one of the fastest changing ecosystems on the planet.

In addition to the climate-related impacts and loss of sea ice, industry is now moving in. While critical for both local and national security, the influx of commercial activities reignites concerns for how to balance economic gain of those in far-flung urban centers from those who remain and rely on the Arctic coastal areas.

As in our own commutes, which require train conductors, transit managers, and regulations to keep us safe on our way to and from work, we will increasingly need to manage new ship traffic resulting from melting Arctic sea ice to keep migrating whales, walruses, and seals out of harm’s way.

Negotiations to address growing offshore oil and gas development have led to an agreement among developers, indigenous hunters, and agencies protecting both people and whales. Similarly, firms shipping through the Arctic have proactively embraced the Polar Code—a carefully negotiated international agreement by interested parties and the International Maritime Organization that will help ensure the safety of mariners and the Arctic marine environment, including those who live in it.

Still, the challenges of ensuring that the Arctic’s wildlife and people continue to flourish remains daunting. It will require working together across cultures and political boundaries to succeed. And it will require engaging fully with both the documentary (photographic) and scientific indications that a warming planet is profoundly impacting the Arctic.

Now more than ever, international bodies, government agencies, and local entities are all needed to help us understand and effectively respond to the many changes roiling a seascape so rich in biodiversity, steeped in culture, and central to commercial trade and transport.