Engineers, commodity, lost keystone species, and pest — beavers have played many roles in Connecticut's landscape.

Their survival is also an astounding conservation success story, according to a new book by local author Leila Philip who explores our relationship with beavers. Where they were once expatriated from the state by the fur trade and trapped to near extinction, in recent decades their numbers have rebounded.

A 2001 state report estimated that there were around 8,000 individual beavers in Connecticut, but it's unknown how many more there are now as they're not actively tracked by the state. But a University of Connecticut project seeks to map where beavers are returning, to better understand their growth and recovery.

And then, how to coexist alongside them and their often beneficial water manipulating habitats.

Most people don't spend much time thinking about beavers, and many people have never seen one. Philip said she was driven to understand beavers, and their significance after a chance encounter while walking her dog in her hometown forests of Woodstock.

"I heard that iconic beaver slap, but I didn't know what it was," she said. "I thought a gun had gone off, truly."

But when she looked for the source of the sound, she didn't find a hunter, nor did she find what was normally a muddy clearing in the trees. Instead she found a silvery pond glinting in the sun, the stillness cut by a little brown head swimming back and forth.

"I was transfixed because of the tenacity of this animal," said Philip. "I came out to watch the beaver every day and saw the transformation of this wet part of the woods into a beaver pond and it was one of the most incredible things I'd ever seen."

Beavers are native to North America. The iconic rodents sport large paddle-shaped tails, webbed paws and teeth laced with iron. They build dams out of small trees, mud and sticks to serve as fortifications for their lodges, dens built out in the water that create dams.

There were millions of beavers on the continent when European settlers arrived. Philip said the scale of beavers on the landscape made the dense acres of trees a "waterworld of great spreading fans of waters throughout the forests."

"That's what we've lost," Philip said. "We filled in 50 percent of our wetlands and that's a problem for us now because those wetlands play such an important function in cleaning our water, slowing our water so it recharges the aquifers."

The fur trade was critical for the formation of Connecticut as a colony, and eventually a state. Philip said beavers were essential for jump-starting transatlantic trade. She pointed to John Jacob Astor, the first known multi-millionaire U.S. businessman who had made his money on the back of a beaver fur monopoly.

"By the 1900s the engines of capitalism are getting going in North America on the backs of the beaver," said Philip. "They trapped, they trapped and they trapped them out. They almost exterminated them."

By the mid-1800s, beavers were all but locally extinct as over-hunting moved them farther north. Early conservationists worked to bring them back. Some were reintroduced to the Yale Forest in 1914. Other reintroductions saw them recolonize local river systems.

But it took until the 1960s for them to truly rebound. Philip said this was due to many river systems being gummed up with industrial uses and the reforestation of farmlands. The beavers finally had habitats that connected, and they thrived.

Geoffery Krukar, a wildlife biologist with the Department of Energy and Environmental Protection said the state didn't have hard numbers on beaver populations here, but he thinks there are a lot of them out there. He said that last year, in 2023, he issued more permits outside the regular trapping season than ever before for incidents of "beaver nuisances" where beavers are removed for threatening property and safety.

"We think they are an important component of the habitat and landscape, but sometimes public safety has to come first," said Krukar. "You can't have roads being undermined or going underwater."

Krukar said that he has denied permit requests for beaver removal, if it lacked a valid reason.

"Like, they just aesthetically didn't want to see trees getting cut down at the edge of a swamp," Krukar said of some requests. "I'll try to preach coexistence in those situations."

But there are some locals that don't want to see beavers removed from their community. About five years ago in South Windsor beaver problems made quite a splash when they created a dam in Nevers Park. DEEP had authorized the town to trap and kill the beavers who after taking up residence had felled 200 trees and caused flooding in the park with a dam. When they found out, outraged locals signed a petition demanding the town find a way to share the public land with the beaver population.

Krukar echoed Philip, saying that beavers were one of the few animals that can create needed habitat on the landscape. He said that beaver wetlands were magnets for biodiversity and supported many kinds of life.

Sarah Heminway, director of the northeast region of the Connecticut Audubon Society said her organization learned to co-exist with beavers. At the Trail Wood Sanctuary in Hampton, beavers had made an acres-wide pond that would breach every 10 years or so in heavy rains. But Heminway didn't want to get rid of the beavers.

"We had many people saying, oh just trap the beavers and take them somewhere else," said Heminway. "But this is perfect beaver habitat, there's no sense in taking them away because they're going to come back."

Heminway reached out to the Beaver Institute in Massachusetts and had them come assess the pond. They settled on installing pond levelers — massive 40-foot pipes that extend to the middle of the pond that work as drains and keep the water from growing beyond a certain depth. The levelers worked, and last year's heavy rains didn't burst the dams.

"We need to stop treating everything as if it is expendable," said Heminway. "That's been the attitude since the Europeans came over on the Mayflower."

She pointed to the regrowth of New England's forests, the return of coyotes, deer, bears, fisher cats and beavers. She said that these animals have a place here.

"We have to live in balance," said Heminway.

Philip cites the story at the Trail Wood Sanctuary in her book "Beaverland: How One Weird Rodent Made America," as an example of fruitful coexistence, noting that in drought months, the beaver pond helped sustain well water in the area. She has data to back this up too, pointing to a 2020 study that estimated that beavers near Milwaukee could provide 1.7 billion gallons of stormwater storage to the tune of about $3.3 billion in ecological services.

"Underneath the beaver pond is an invisible sponge in the ground," said Philip. "If you have a beaver pond that holds a million gallons of water, about three million gallons of water are being held in the soil underneath. That's a huge sponge that'll recharge a creek when a drought comes."

Philip hopes her book, and talking to locals in Connecticut can help change our perception of beavers.

"There are many ways in which people realize how it is in their interest to have beavers," said Philip. "They can reverse our cultural habit of thinking we need to kill beavers."