{"id":35969,"date":"2021-08-03T00:05:44","date_gmt":"2021-08-03T07:05:44","guid":{"rendered":"https:\/\/hakaimagazine.com\/?post_type=custom_features&p=35969"},"modified":"2023-07-03T16:44:09","modified_gmt":"2023-07-03T23:44:09","slug":"the-ingenious-ancient-technology-concealed-in-the-shallows","status":"publish","type":"custom_features","link":"https:\/\/hakaimagazine.com\/features\/the-ingenious-ancient-technology-concealed-in-the-shallows\/","title":{"rendered":"The Ingenious Ancient Technology Concealed in the Shallows"},"content":{"rendered":"
\n

Congratulations to Brian Payton on winning a Canadian Archaeological Association Public Communications Award<\/a> for this article.<\/p>\n<\/div>\n

It was a cool spring morning on British Columbia\u2019s Vancouver Island when the ground began to buckle and heave. On the Richter scale, the earthquake reached a magnitude of 7.3 at a place called Forbidden Plateau. Seventy-five years later, it still holds the title as the most powerful onshore quake ever recorded in Canada. In nearby communities, brick walls fell and three-quarters of all chimneys collapsed. Two casualties were recorded that day: one man died of heart failure and another drowned after his dinghy was overturned by a wave generated when a piece of land gave way and thundered into the sea. For a while, that seemed like the end of the story. But over time, the changes wrought by the quake revealed a mystery that had lain hidden for generations\u2014long enough to be forgotten.<\/p>\n

Twenty-two kilometers from the quake\u2019s epicenter, locals started noticing wooden stakes appearing in the intertidal zone of Comox Harbour on the east side of Vancouver Island. They ranged in size from the width of an adult\u2019s thumb to the width of an arm, but stuck out little more than ankle high from the sand and mud. Locals pondered the mystery; many assumed they were the leavings of some relatively recent industrial activity, or a fishing scheme abandoned by immigrants from Japan.<\/p>\n

In 2002, Nancy Greene, then an undergraduate anthropology student, walked among the barnacle-encrusted stakes and thought she\u2019d found a fascinating subject for her senior project at Malaspina College (now Vancouver Island University). She had lived in the area since 1978, raised her children here, and was up for a new challenge. Little did she know it would consume countless hours, span more than a decade, or eventually reveal the largest unstudied archaeological feature yet found on the Pacific Northwest coast\u2014one that would tell a remarkable tale of human ingenuity and adaptation in an era of climate change.<\/p>\n

\n

On the eastern slopes of the Beaufort Range, rain and meltwater flow down the Puntledge and Tsolum Rivers and converge in the Courtenay River before reaching Comox Harbour. These sheltered waters are part of the Salish Sea, which stretches from British Columbia\u2019s Inside Passage down to Washington State\u2019s Puget Sound. People have been living off the bounty of this marine environment ever since they began arriving in the region near the end of the last ice age, about 13,000 years ago. Comox Harbour lies within the protected waters of a broad, gently sloping estuary that covers an area of 9.6 square kilometers, slightly bigger than Golden Gate Park in San Francisco, California. It is the traditional territory of speakers of the sleeping Pentlatch language, whose descendants form part of the 342-member K\u2019\u00f3moks First Nation, which along with the communities of Courtenay and Comox now surround the harbor.<\/p>\n

\"map<\/a>

Map data by OpenStreetMap via ArcGIS<\/p><\/div>\n

There had always been a few bits of wood poking up through the sand and mud of Comox Harbour, but after the quake of 1946, thousands of stakes emerged across vast stretches of the intertidal zone. This was likely a result of liquefaction, a phenomenon in which shaking reduces the strength of the sediment and leads to erosion. Subsequent periods of dredging near the mouth of the river may have also contributed to the process. It was clear the stakes formed patterns, but just what those patterns represented was a puzzle until quite recently. In her interviews with members of local Indigenous communities, Nancy Greene found only one clue: a K\u2019\u00f3moks elder said that her grandmother told her the stakes were used to catch salmon, and that families owned specific weirs and were tasked with maintaining them.<\/p>\n

Cory Frank, manager of the K\u2019\u00f3moks Guardian Watchmen, encountered the stakes as a child and also pondered the mystery. But when he asked his elders what they were, they didn\u2019t seem to know. What was well known were the frequent battles that took place in the harbor before colonization. Those foolish enough to attempt a raid on the people living here, or their rich resources, faced harsh consequences. \u201cWhat we did with people like that was chop their heads off, put them on a spear, toss them in the sand, and leave them as a reminder for other people not to come.\u201d<\/p>\n

Frank clearly relishes relaying the tale, a testament to the abundance of salmon and the tenacity of the people protecting their claim to Comox Harbour. Now, as the history of the stakes is becoming known, he says they are a source of pride in his community.<\/p>\n

\"Nancy<\/a>

Nancy Greene studying the massive fish trap complex in Comox Harbour on Vancouver Island, British Columbia. Photo courtesy of Nancy Greene<\/p><\/div>\n

Uncovering that history required hands-on research. In 2003, after surveying the entire estuary, Greene pulled on her gumboots and set out with pin flags and a laser theodolite to take geolocations of stakes across an area encompassing a total of approximately 30 hectares. She enlisted her husband, retired geologist David McGee, and a team of volunteers to help find and mark the stakes while trying to outrun the incoming tide. Because not all tides are created equal, she had to account for variations in how much area a tide exposed, available light, and weather. After months of reconnaissance, then weeks of recording geolocations, she recalls that first moment seeing the information they had collected displayed on a computer screen. Suddenly, those individual nubs of Douglas fir and western red cedar became 900 little black points on a field of white\u2014like a photographic negative of stars in the nighttime sky. Patterns began to emerge and repeat. It took months of analysis, she says, before she began to realize what they represented\u2014the remains of an immense, highly coordinated, and sophisticated fish trap system, the largest such system discovered in North America, if not the world.<\/p>\n

\n

Think Hotel California for fish\u2014they can easily check in, but they can never leave. Such is the purpose of fish traps, ingenious systems for catching wild fish and practicing fishery management the world over. Fish weirs, like the ones that appeared in Comox Harbour, are a specific kind of fish trap built as an obstruction across a river or tidal waters. Fish seeking shallows, or spawning grounds farther upstream, swim in with the tide and can\u2019t escape. The ancient technology relied on a deep and intimate knowledge of local fish behavior.<\/p>\n

Evidence suggests that complex hunter-gatherer cultures around the world invented fish traps independently at different places and times. Unlike wooden stakes, rock assemblages used in other fish weirs are difficult to date, but radiocarbon dating of adjacent middens (piles of fish bones and shells) offers a kind of proxy. Some of the oldest confirmed traps in North America are on mainland British Columbia at the mouth of the Fraser River (4,500 to 5,280 years old) and in Maine (5,770 years old). The oldest-known fish traps, between 9,000 and 7,000 years old, were found in northern Europe. But the technology is probably far older. A line of stones found on the shore of an ancient lake in the Kenya Rift is reminiscent of the fish weirs used by the local people in modern times. It dates to the time of Homo erectus<\/em> or at least 490,000 years ago. If this was indeed a weir, it would mean the technology predates modern humans.<\/p>\n