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WILLIAMSBURG, VA--The worst droughts of the past 800 years likely played a major role in the mysterious disappearance of Roanoke Island's "Lost Colony" and in the "starving time" endured by colonists at Jamestown, researchers from the College of William and Mary and the University of Arkansas have concluded after studying growth rings of ancient trees in the Tidewater area. The findings were just published in the current issue of Science journal.
"If the English had tried to find a worse time to launch their settlements in the New World, they could not have done so," said Dennis B. Blanton, director of the William and Mary Center for Archaeological Research. "From 1587 to 1589, the most extreme drought in 800 years is implicated in the disappearance of the Lost Colony, and the Jamestown settlement was later plagued by the driest seven-year episode in 770 years. These droughts make the dry summer of 1997 pale in comparison."
The researchers' findings were based on an examination of ancient trees in the nation's southeastern Tidewater region. The project was funded by the National Park Service as part of the Jamestown Archaeological Assessment project, a cooperative project among the College of William and Mary, the Colonial Williamsburg Foundation and the National Park Service.
The Roanoke Island settlement was established in 1587 but settlers soon mysteriously disappeared, leaving only the enigmatic word 'Croatoan' carved on a tree. More is known about the hardships at Jamestown, which was founded in 1607 but nearly failed during the period from 1609 to 1610 -- historically known as 'the starving time'-- when the colony suffered 'an appalling death rate.' According to historians, 43 percent of the 350 colonists alive in June of 1610 were dead by the end of that summer.
Blanton, who has long been intrigued by the events at Jamestown, asked University of Arkansas climatologist David W. Stahle to undertake the tree-ring study after hearing of his work. Several years ago, a team of researchers from the tree-ring laboratory at Arkansas had conducted general climate studies along the East Coast by taking nondestructive core samples from selected trees. Blanton asked them to examine the core samples taken specifically from centuries-old baldcypress trees in swamps along the Blackwater and Nottoway Rivers on the Virginia-North Carolina border.
"I had read articles about their work and thought we could use the data in archaeology," Blanton explained. "I was trained as a prehistoric archaeologist, and we routinely look at environment to see what role it has played. You don't do any study in prehistoric archaeology without first understanding the limitations of the environment."
At Blanton's request, Arkansas climatologists spent several months analyzing the existing core samples, which covered the period between A.D. 1185 and 1984, for information about rainfall and temperatures during the Tidewater growing season. Archaeologists from William and Mary's Center for Archaeological Research did extensive historical and archaeological research into past Tidewater climate conditions. Both groups then correlated and interpreted the data.
"The tree-ring data indicate the extraordinary drought conditions that attended the settlement of both the Roanoke and Jamestown Colonies," the Science article says. A tree growth anomaly map for the period 1587-1589, for example, shows that the Lost Colony drought affected the entire southeastern United States, but was particularly severe in the Tidewater region near Roanoke. The cypress growth anomaly map for the Jamestown drought, 1606-1612, reveals that the most severe drought conditions during that period occurred in the Tidewater region near Jamestown. (An anomaly map illustrates specific conditions -- in this case growing-season precipitation -- over a certain geographical area.)
"The Roanoke and Jamestown colonies have both been criticized for poor planning, poor support, and for a startling indifference to their own subsistence," concluded the writers in Science. "But the tree-ring reconstruction indicates that even the best planned and supported colony would have been supremely challenged by the climatic conditions of 1587-1589 and 1606-1612."
The Jamestown drought, for instance, decimated corn crops on which the colonists depended and aggravated tense relations with the native Powhatan Indians. Blanton speculated that when the Indians could not supply food to the colonists as promised, hard feelings followed and conflict erupted. The dates of at least two Anglo-Indian wars correlate perfectly with the droughts, he said.
Drought also affected the quality of the colony's critical water supply. "Poor water quality is another factor implicated in the ill health suffered at Jamestown, and water quality at Jamestown is poorest during drought," said the Science article. "The lower James River is a brackish estuary, and there are archival references to foul drinking water and associated illnesses among the settlers, particularly before 1613."
During the drought, many people starved, and some of the Jamestown colonists eventually resorted to cannibalism. Citing a staggering death toll that nearly forced abandonment of the colony, the Science article notes that "only 38 of the 104 original settlers were still alive after the first year at Jamestown, and 4,800 out of the 6,000 settlers sent to Jamestown between 1607 and 1625 died during this extraordinary period."
"The colonists were expected to live off the land and off trade and tribute from the Indians. But this subsistence system would have left the colonists extremely vulnerable during drought."
Members of the Roanoke Colony -- last seen in August of 1587 -- are thought to have been similarly afflicted by extreme drought from 1587 to 1589, the area's driest three-year period in 800 years.
"I am not an environmental determinist," said Blanton. "Other factors clearly played a role in the demise of the Roanoke Island settlers and the hardships of those at Jamestown, but the droughts were certainly among the most serious problem both groups faced."
"Only multidisciplinary research could lead to such exciting discoveries as these," he added. "History, archaeology or climatology alone could not have reached these conclusions, but a combination of the disciplines enabled us to discover these significant patterns."
Dennis Blanton is available for interviews at (757) 221-2584.
Cutlines for Jamestown Visuals
1. In this Sidney King painting, "Burial of the Dead During the Winter of 1609- 1610," two colonists carry a body out of the fort at Jamestown. A minister, left, leads the solemn procession. Onlookers and the church at Jamestown are in the background, at right. The painting is owned by the National Park Service, Colonial National Historical Park, and hangs in the park service's visitor center on Jamestown Island.
2. This Sidney King painting, an aerial view of Jamestown Island, depicts Jamestown Fort and New Towne, with several ships in the James River. The painting hangs in the National Park Service Visitor Center at Jamestown Island.
3. Section of Nottoway River bald cypress tree showing the annual growth rings. Rings are closer together during periods of drought. Photo courtesy Colonial National Historical Park.
4. Aerial view of Jamestown taken in the spring of 1995. Photo courtesy Colonial National Historical Park.
5. David Stahle coring an Arkansas baldcypress tree in 1980. Photo courtesy Colonial National Historical Park.
6. Brick building foundations at Jamestown photographed in the summer of 1995. Photo courtesy Colonial National Historical Park.
7. Location of Roanoke Island, Jamestown Colony, and baldcypress trees from the Blackwater and Nottoway Rivers used for the tree-ring study.
8. Tree-ring reconstructed July PHDI* for the Tidewater region of Virginia and North Carolina from A.D. 1185-1984 (A), and for the early colonial period from 1560- 1720 (B). The most extreme growing-season drought of the past 800 years was reconstructed for 1587, the year the colonists on Roanoke Island disappeared. The Lost Colony Drought of 1587-1589 was the most extreme three-year episode in the entire 800-year reconstruction. The prolonged Jamestown Drought lasted from 1606-1612, and was the worst seven-year drought reconstructed for 770 years (from 1215-1984). (*PHDI is the Palmer hydrological drought index)
9. A Jamestown colonist is depicted in this Sidney King painting, "Starving Time, 1609-1610." A house and fort are in the right background. The painting is owned by the National Park Service, Colonial National Historical Park, and hangs in the park service's visitor center on Jamestown Island.
10. Tidewater cypress trees like this one near Jamestown, Va., were used in the drought study. Climatologists from the tree-ring laboratory at the University of Arkansas took nondestructive core samples from centuries-old baldcypress trees in swamps along the Blackwater and Nottoway Rivers on the Virginia-North Carolina border. Researchers spent several months analyzing core samples, which covered the period between A.D. 1185 and 1984, for information about rainfall and temperatures during the Tidewater growing season. Archaeologists from William and Mary's Center for Archaeological Research did extensive historical and archaeological research into past Tidewater climate conditions, and then both groups correlated and interpreted the data.
11. Dennis Blanton, director of the Center for Archaeological Research at the College of William and Mary initiated the drought study. Blanton, pictured here near one of the archaeological sites on Jamestown Island, asked University of Arkansas climatologist David W. Stahle to undertake the tree-ring study after hearing of his work. "I thought we could use the data in archaeology," said Blanton. "I was trained as a prehistoric archaeologist, and we routinely look at environment to see what role it has played." (photo by James Gleason/VISCOM)
12. Aerial view of Jamestown Island taken in 1997. Photo courtesy Colonial National Historical Park.
13. Composite photo of Sidney King's painting, "Building of the James Fort, May and June, 1607," depicting the building of Jamestown Fort (top), and a close-up of a tree ring segment used in the drought study (bottom). (Photo composite by University of Arkansas tree-ring laboratory.)
14. Ancient baldcypress tree at Devil's Gut along the lower Roanoke River, N.C.
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