Every other Friday, the Outside/In team answers a listener question about the natural world. This weeks question comes from Tyler in South Carolina.
"What is the significance of the color red being used with light houses?"
Outside/In producer Marina Henke looked into it.
Transcript
This has been lightly edited for clarity.
Marina Henke: It may be tempting to think of lighthouses as stand-alone tourist attractions, perched on rocky outcrops, maybe flashing a lone light across the water. But 100 years ago, the federal U.S. Lighthouse Service maintained nearly 1,000 functioning lighthouses across the country.
Jeremy D'Entremont: They built enough lighthouses eventually so you were never out of sight of a lighthouse.
Marina Henke: Jeremy D’Entremont is a historian for the U.S. Lighthouse Society. And during this heyday of lighthouse navigation he described the resulting effect as a “light network” strung along the coast. Like our listener noted, it was a network with a whole lot of red.
Jeremy D'Entremont: Sankaty Headlight on Nantucket, White Shoal Light in Michigan. . . . On Cape Cod, Nauset Light is kind of an iconic lighthouse.
Marina Henke: Beyond making for dashing gift-shop keychains, the reason for this popular hue is two-fold. First is that the color red often helps lighthouses stay visible. To be seen, after all, is the primary purpose of a lighthouse.
Jeremy D'Entremont: I always tell people they’re kind of like the signposts of the sea.
Marina Henke: But these “sign posts of the sea” are only useful if sailors can spot them. At night, a lighthouse’s beam does the trick, but during the day that flash of a bulb can be pretty hard to spot, which means a lighthouse’s paint job actually matters a lot.
Jeremy D'Entremont: I should point out that in New England, most of our lighthouses are a very simple white, with black iron lanterns.
Marina Henke: Against the dull browns and grays of a New England coastline, white stands out. But, not always. Just like an outfit, sometimes a lighthouse benefits from a pop of red.
Jeremy D'Entremont: For instance, in Maine, West Quoddy Head Light at the easternmost point of the United States has red and white stripes. There's a pretty fair amount of snow up there. So the red shows up really well against the snow background.
Marina Henke: Red, it turns out, is a highly employed color in the nautical world. That’s because our eyes pick it up extraordinarily well — yes, against snow, but also water. The second reason for red’s popularity comes from a lighthouse’s need to be unique. With so many white lighthouses along the coast, sailors found that the structures could be hard to tell apart.
Jeremy D'Entremont: So they decided to give some lighthouses distinct paint schemes or "daymarks" as they’re known.
Marina Henke: These daymarks are the reason for the delightful variety in light house patterns that exist today: red checkers, red diamonds, black stripes. All these variations leave most lighthouses with their own unique fingerprint. They’re cataloged in a yearly report that the Coast Guard puts out called the U.S. Light List.
Today, lighthouses are often a backup to more high-tech instruments. But, it doesn’t mean these structures are without a purpose. After all, sometimes tech fails.
Jeremy D'Entremont: You know, people tell me all the time, they still like seeing that lighthouse . . . that actual physical confirmation of where they are.
Marina Henke: Whether it’s the stripes of West Quoddy or the thick band of Nauset Light, there’s a sailor out there who knows that red marking means they’re coming home.
If you’d like to submit a question to the Outside/In team, you can record it as a voice memo on your smartphone and send it to outsidein@nhpr.org. You can also leave a message on our hotline, 1-844-GO-OTTER.
