Assistant Keeper Marcus E. Howes stood watch in the lighthouse on April 1–2, 1902, the night when the ducks came crashing in. In the April 5 edition of the Nantucket Inquirer & Mirror , the closest news organization to the lighthouse, a reporter stated that, “At midnight Tuesday, assistant keeper Marcus E. Howes of Great Point light started downstairs to call the keeper [Joseph W. Nickerson] to take his watch.” The April 3 Portsmouth Herald , in New Hampshire, had the situation differently: “To the fact that he had left his post a moment to get a drink of water, Assistant Lighthouse Keeper Howes, of the Great Point station, attributes his escape from injury in a remarkable way, which occurred here today and in which two canvasback ducks caused considerable damage to the lighthouse.” So which was it? In the end, it doesn’t matter, of course, as Assistant Keeper Howes is no longer available to stand up to inquiry. The real story here is the impact. “Just after midnight,” wrote the Portsmouth Herald , “Keeper Hawes [sic] left his position and had scarcely stepped down from his station when a loud crash was heard at the same instant the light went out.” “Hastening back to the lantern room,” continued the Nantucket Inquirer & Mirror , “he found everything in confusion.” From what Howes could ascertain, “two great canvasback ducks of a species rare in this section had plunged through one of the large plate glass windows.” The window in question was six feet high, 27 inches wide and 3/8 of an inch thick. The average windowpane in the 1900–1915 time period was approximately 1/10 of an inch thick, according to the Society for Historical Archaeology. But the larger the window, the greater the need for more thickness; thus, this six-foot-tall windowpane was more than three times the thickness of the average homeowner’s window. The ducks, or at least one of them, smashed the window to “atoms” according to the Nantucket paper, and “no piece of glass bigger than a half dollar could be found,” said the Portsmouth Herald . The Canvasback blasted through the glass, extinguished the light inside the third-order Fresnel lens and smashed into a window on the opposite side. The Herald claimed that two ducks came in through the window, while the Inquirer & Mirror stated that, “When morning dawned, the mate to the duck was found at the base of the tower.” What shocked Howes most, though, was the astonishing timing of his absence from the spot of impact, “as the man on watch is accustomed to stand near this window,” said the Herald . “It is thought that he could not have escaped injury from flying fragments had he been in his place.” The crash came with both familiarity and mystery. “It is no unusual occurrence for sea fowl to fly against the lanterns of lighthouses and be killed,” stated the Inquirer & Mirror , “but it is rarely they break the heavy plate glass of the lanterns.” Perhaps most startling was the species of duck in question. “On account of the rareness of the species there is much surmising as to where they came from,” said the Herald . Canvasbacks are known as prairie pothole ducks, most often found in the western half of the United States, though they have historically occurred in eastern North America, if in much smaller numbers than are seen out west. In 1900, Reginald Heber Howe and Glover Morrill Allen wrote in The Birds of Massachusetts that it was at that time a “very rare autumn migrant along the coast,” listing Nantucket as one of the ten places in which it had been seen in recent memory. The authors did admit, though, to spring migration dates of March 20 to 31. Observers in Taunton, Massachusetts, had recorded one visitation in 1884. A reporter from Essex County, along the coast north of Boston, called it “very rare,” while word from Nantucket was that it was simply “rare.” More than a century later, Massachusetts birders still consider a Canvasback a quality checkmark on any bird list generated within the bounds of the Commonwealth. Canvasbacks are diving ducks (dabbling ducks tip their posteriors skyward and submerge their heads to tug at reachable plant growth in shallow ponds; diving ducks swim underwater for their food); moreover, they are one of the largest diving ducks in North America. The lighthouse keepers estimated that the birds weighed about seven pounds apiece that day, but repeated modern measurements put them at much less than that, in a range between 862 and 1588 grams, or 1.9 to 3.5 pounds. Their size allows them to generate terrific flight speeds. According to Ducks Unlimited, until recently eclipsed by a Red-breasted Merganser clocked at 100 miles per hour, a Canvasback held the record for fastest known duck, at 72 mph. The Portsmouth Herald believed that the individual that struck the lighthouse had hit the 100 mph mark, which was possible. Mallards flying 50 mph with a 50 mph tail wind have been known to cover 800 miles in eight hours. According to the Inquirer & Mirror , on the night in question, “the wind was blowing a gale from the west.” We can estimate the force of the Canvasbacks’ impact on the lighthouse window. An average-sized duck, traveling at 70 mph would have produced the same amount of pressure—in physics terms, about 0.65 pound-force per square inch (psi)—on the glass as a 62-pound object would if it were set on top of it. That is roughly equivalent to setting a boxer’s heavy workout bag on the glass. If we assume that the bird was on the larger end of the scale and traveling at 100 mph, the analogous force would have been closer to setting several bags of concrete or a stack of three cinder blocks on the glass. Being toward the northern end of the Canvasbacks’ migration probably saved the lighthouse more extensive damage, as the species tends to fly in large mixed (male/ female) flocks until pairing up near its breeding grounds. The fact that only two birds struck the tower probably means that these Canvasbacks had moved into that final phase of their migratory flight. Imagine the fireworks that would have resulted in the lantern room if an entire flock had hit the lighthouse at the same time. Sad to say, birds strike windows at an alarming rate. While many people have seen or heard a bird hit a window, they tend to believe it is an unusual event. However, the American Bird Conservancy estimates that up to a billion birds die in collisions with glass each year in the United States…the number is staggering. It’s also unsustainable for our overall bird populations. David Sibley, author of the popular Sibley Guides to North American Birds , writes, “Birds see the natural habitat mirrored in the glass and fly directly into the window, causing injury and, in 50% or more of the cases, death.” There is hope, though, he says: Simple steps can be taken to reduce the number of birds striking windows. Decals that stick to the glass are not very effective, but strips of tape on the outside of the glass, or strings or feathers hanging outside the window, each no more than 10 inches apart, are fairly effective. Decorative features like stained glass designs or window dividers can achieve the same result. Outside screens are very effective both to reduce the reflection and to cushion the impact. In short, anything that reduces or breaks up the window’s reflection will reduce bird strikes. Traveling at night—as the Canvasbacks of Great Point Lighthouse did in 1902—comes with its own danger. Birds can become disoriented by artificial light, leading to collisions with buildings. Mass Audubon is leading the “Lights Out Boston” campaign with city leaders with the intention of lessening or eliminating this danger to birds during the spring and fall migrations. Large-scale efforts like this one could save thousands of avian lives. As to the results of the impact, “Word of the disaster was at once telegraphed to the department and meanwhile temporary repairs will be made by the keepers that the light may be kept burning to guide mariners on their way,” said the Inquirer & Mirror . Needless to say, the birds died. That fact did not mean that they were lost forever, though. “They will be preserved as trophies by the life savers,” said the Herald , presumably at the nearby Coskata Life-Saving Station. And Assistant Keeper Howes, though he would leave the lighthouse the following year, would never forget the night the Canvasbacks paid Great Point Lighthouse a visit. References American Bird Conservancy. 2015. Glass Collisions . Accessed November 19, 2015. Ducks Unlimited. 2015. Waterfowl on the Move . Accessed November 19, 2015. Howe, R. H. and G. M. Allen. 1901. The Birds of Massachusetts . 50-51. Published by subscription. Cambridge, Massachusetts. The Inquirer and Mirror [Nantucket]. “Crashed Through Lantern.” April 5, 1902. Portsmouth Herald . “By Two Big Ducks.” April 3 1902. Sibley, D. 2003. Causes of Bird Mortality. Sibley Guides . Accessed November 19, 2015. John J. Galluzzo is the development writer for the South Shore YMCA, formerly the director of education and camping for the South Shore Natural Science Center, and ran adult education and citizen science programs for Mass Audubon’s South Shore Sanctuaries. He also holds the Thomas and Phyllis Tag Fellowship for lighthouse history research through the United States Lighthouse Society. His brother-in-law Christopher E. Degni graduated from the University of Chicago with a PhD in Mathematics and has worked in the defense industry for the last decade. They live in Hanover and Weymouth, Massachusetts, respectively.