Category: BDA’s

BDA’S ARE THE FRANKENSTEINS OF THE NATURAL WORLD

heidi08 BDA's, Beavers October 13, 2022

Mary Shelley missed her calling. Reanimating dead stream tissue is just as hard as making a monster out of spare parts. When you think about it that’s what BDAs are really. A good article about them should have at least 4 of those parts. (1) A description of the benefits they are trying to replace (and their benefactor), (2) an explanation of how it all used to work originally, (3) the necessary Igors and volunteer believer labor to pull it off and (4) a hope that beavers will come back and take over the work. Let’s be honest. The wish for beavers to COME BACK is the only part that makes it NOT a Frankenstein story.

If the first and last parts aren’t included in the article you should run as far as you can in the opposite direction because what you’re actually watching is a horror film. But this one from Oregon is pretty close to being a role model. Every stream should be so lucky.

Restoring Sisters County Wetlands

Mike Riehle stands knee-deep in life returning.

“Not long ago this whole area was dry,” he says, gesturing over weeds and decaying willows. “We’re hoping these efforts will fix that.”

That area, the Lower Black Butte Swamp, is a 50-acre parcel that was once parched land, and is now by design — flooded with water.

The gradual decline in this regional ecosystem was set in motion by the void left from one of nature’s finest eco-engineers — the beaver. Beyond its iconic status as Oregon’s state symbol, these mammals have a unique talent: fabricating natural dams that disperse water into the surrounding environment. Their constructs are a vital resource, irrigating surrounding vegetation and cultivating habitat for wildlife to thrive in.

In 2011, the last known beaver disappeared from the swamp. Without their dams, Indian Ford Creek, running through the wetland, narrowed and the surrounding ecosystem lost its lifeline as water levels dropped. Willows died, their silvery corpses now dotting the undergrowth, grass sedges collapsed, and noxious dry-climate weeds, such as the common mullein and tansy ragwort, colonized the landscape. As the biology of the swamp changed so did the presence of wildlife. The former wetland became a dry wetland, absent its bio-diversity. The remaining water source was the perennial flow of Indian Ford Creek along a single, narrow channel.

Now THAT is what sets the stage for a good BDA article. We used to have this splendid resource that now we don’t anymore and so we want to fix it. I’d love to see a similar article about Alhambra Creek now that our beavers are gone. It’s a miserable trickle compared to what it once was. We all know it.
And that. THAT is the kicker. Good job guys. The stage is set.

Riehle, the fisheries biologist for the Sisters Ranger District, says the concern turned to worry, and in January of 2022 the District drafted plans to find a solution. Their solution was simple: construct a series of BDAs (Beaver Dam Analogue), or man-made dams, to restore the native habitat, and replenish the underlying water table as nature once did. In June, natural materials were collected, and in September physical work began on the Lower Black Butte Swamp Restoration Project.

A LIDAR image, taken in 2011, was utilized to 3D map the terrain, and sketch a plan for reestablishing the native path of the creek, identifying key points to construct the dams. Using one-foot contour lines they would methodically restore the swamp’s natural flow.

Despite modern technology, constructing a beaver dam by hand requires basic hand tools and the realization that nature’s architects know something humans don’t.

“Beavers are great engineers but they haven’t exactly shared their formula with us,” Riehle says.

Every word of this article is perfectly written to emulate – not REPLACE- the good work done by beavers. Remember that Oregon still allows trapping on public lands. This article is quietly giving reminders why that needs to change.

Sisters Ranger District Hydrologist Jamie Sheahan Alonso, echoed his sentiment.

“No one on our core team has ever done this before,” she said.

The concept of BDAs isn’t new, but the art of constructing and implementing them, and their desired impact on the local ecology, is a study in progress.

A total of 26 BDAs were constructed along a 2,500-foot stretch of Indian Ford Creek, requiring considerable resources and crews in a process once designated to a handful of beavers. Prior to building, members of the Youth Conservation Corps snorkeled, collecting and relocating 310 fresh water mussels from the construction zone.

To build a man-made dam involves strength and the ability to shape nature’s fabric. Lodgepole pines are embedded into the creek bed three feet deep, and across the width of the creek. Cottonwood branches are then handwoven along the length and depth of the poles to the bottom of the creek, then consecutively stacked to create a water break. Clumps of sod and grass sedges are hand-placed at the bottom of the weave to prevent water from seeping under and uprooting the poles. Juniper branches are inserted perpendicularly into the weave, stretching upstream and downstream to reduce the water turbulence, further securing the integrity of the design and preventing poles from being uprooted by the current.

Lots of people with lots of tools and technology can barely accomplish what beavers were doing without any government funding or equipment. You got that, right?

As teams stack branches, the weave increases in depth, and sod is reapplied, acting as a mortar sealing the branches into place.
Once dams are set in place, the effects are immediate: Creek water levels rise multiple feet within minutes and begin seeping horizontally into the dry plain. The intended effect on the water table is quickly observed too.

“After our first three dams were built, we noticed a six-foot rise in the water table within the 24 hours,” Riehle said.

Upstream, the formerly dry and arid landscape now sits under a foot of water as a result of only a handful of dams. That water will eventually soak into the earth, says Sheahan Alonso. And with that comes a reinvigorated landscape that will someday turn green again.

The challenging manual labor was done by the Heart of Oregon Corps, who provided over 20 personnel for the project, and employees of the Sisters Ranger District. An excavator was also hired to set poles into the creek bed and dig up sod for the dams.

John Deluka, the Sisters Ranger District wildlife biologist, stood waist-deep in the effects of his freshly constructed BDA, weaving another cottonwood branch into place while ruminating on its rising benefits.

“This ecology is suffering and I hope this project will bring back the beavers and other wildlife that once thrived here,” he said.

Deluka noted that 115 bird species have been recorded in the swamp alone and more than a dozen animals, including elk, roam the terrain.

“I expect those numbers to increase after this project, and I hope to hear a symphony of frogs when this place recovers,” he said.

Wildlife is a key attribute to restoring the biological habitat, but that wildlife is only a glimpse of the bigger ecological picture, he said.

The Lower Black Butte Swamp is a small part of a larger ecosystem that directly affects the climate. Scientific studies show that three percent of the earth’s surface is wetlands, similar to the Black Butte Swamp. And one third of CO2 and methane is absorbed into its soil, which is then naturally converted into oxygen. Restoring the “wet” to a wetland reactivates that function.

Deluka says with the return of healthy habitat, the land and those within it can only thrive.

And in the Black Butte Lower Swamp, those restorative effects are beginning to take shape. Much of the wetland is now wet again. Riehle says the noxious weeds will die off with the overabundance of water, and the sedges, willows, and other native habitat will start to recover in time. He ultimately hopes the water table will continue to rise and nature will find its way back, and hopefully beavers will reinhabit the area.

“Water is life,” said Deluka. “And we’re just trying to restore that.”

HOPEFULLY BEAVERS WILL FIND THEIR WAY BACK. HOPEFULLY. It occurs to me with your last quote about restoring life that BDA’s are kind of like the Frankenstein of the ecological world. You are basically reanimating dead tissue and to be honest the creature you end up with is nothing like the beaver dam you are replacing. But it’s more alive than it used to be and I guess that’s the point.

We need more beavers and fewer Frankensteins.

MAKING WAY FOR BEAVERS STARTS IN NM

heidi08 Attitudes towards beavers, BDA's, Beaver ecological impact September 16, 2022

Does your landscape need beavers but can’t support them yet? No willow trees or good places to hide? Every journey starts with a single step. Maybe this is how you need to make a kind of prebeaver readiness.

Beaver dam analogs bring ecosystem benefits in areas where habitat won’t support beavers

Beavers are increasingly viewed as an important part of the efforts to mitigate impacts of climate change, but in some parts of New Mexico the former beaver habitat has been destroyed.

In those situations, the New Mexico Department of Game and Fish will sometimes turn to man-made structures that mimic beaver dams. These structures are known as beaver dam analogs.

Ryan Darr, a spokesperson for the New Mexico Department of Game and Fish, said in an email that the department has seen the natural development of off-channel habitat as well as the expansion of riparian areas after the installation of beaver dam analogs.

Within one or two growing seasons, the riparian and aquatic habitat improvements linked to beaver dam analogs have benefited wildlife and fish.

Darr said there are several types of beaver dam analogs. Some of them are classified as post-assisted. These require using untreated wood posts that are approximately three inches in diameter and mechanically driving them into the streambed. The posts are placed about 18 to 30 inches apart and then, Darr said, locally sourced materials like leaves, branches and live materials are woven between the posts. The holes are filled with turf, mud, sod, rocks and other local materials.

Darr said other beaver dam analogs are made without posts. These use stumps and root balls as well as piles of woody debris which are placed at strategic locations in a stream.

The beaver dam analogs help restore the habitat and may pave the way for beavers to eventually return to those stretches of stream. Darr said beavers could possibly be reintroduced or they could expand upstream to the areas where the beaver dam analogs have helped to restore the habitat.

You know how it is. Before the queen’s procession can proceed down the narrow streets a row of men with brooms and dustbins must clear the path. You have to EARN beavers. Unless you’re lucky and they just come naturally.

Beavers are often referred to as ecosystem engineers thanks to their impacts on streams, which include creating ponds and excavating canals and burrows along stream banks and in riparian areas.

Prior to European settlement in North America, scientists estimate that there were between 60 and 400 million beavers, which lived in all regions of the United States except for some of the arid southwest and the Florida peninsula. That number has been reduced to about 10 million.

“If you went back a little over 100 years, it would have been difficult to find beavers in most watersheds in the state because beaver populations and habitat were depleted due to the lack of regulations on industry, hunting, and trapping,” Darr said.

He said that one of the first game laws in the state was intended to restrict beaver hunting and trapping and, thanks to modern wildlife management practices, the beaver populations have been recovering.

“What we’ve found in recent years is that there are beavers in most of our watersheds across the state if there is suitable habitat, and in many places those populations are thriving,” he said. “Places where beavers may have been historically, but we don’t find them currently, usually don’t have suitable habitat and need improvements to riparian vegetation, aquatic habitat or land management practices to become suitable. These are locations where BDAs can often be applied successfully.”

Beavers were extensively hunted and trapped for their pelts. Beavers have also been considered pests that can cause flooding and property damage.

In recent years, there’s been an increased push by states to promote beaver habitat recovery.

This week, California’s Department of Fish and Wildlife posted its first job opening for its new beaver restoration unit as the state looks to the semi-aquatic animal for help in the fight against climate change.

Beaver dams, and analog structures, can improve water quality by trapping sediment in the ponds created by their dams and by slowing water flows during spring snowmelt and monsoons, Darr said.

Even when the water is flowing at normal levels, the dams help some rivers and streams maintain consistent flows for longer during dry periods of the year, he said. This is because the dams slowly release the water.

Yes well bda’s are nice. But we all know B’s are better. They do the work themselves. Do the maintenance themselves. And have better instincts. More experience on the job. No offense.

The water in the beaver ponds tends to be colder during the summer months than flowing water in the river or stream, which benefits the fish species, Darr said.

While scientists have found numerous benefits to beavers’ activities, a recent review published this month in the journal Global Ecology and Conservation found that more work is needed. The review analyzed 267 peer-reviewed studies and found that most have been completed in temperate forest environments and that many biomes are understudied. The authors wrote that additional research is needed in some areas, such as in arid environments.

“Over the last decade, the introduction and conservation of beaver for stream restoration has become increasingly common. This study provides a reference for how specific variables may be expected to respond to beaver dams within and among biomes. It is important to note that each watershed is complex and has a unique combination of climate, underlying geology, soils, vegetation, biota, land use history, and current land use demands,” the authors wrote.

THE TREASURED AND RARE ‘HYPOTHETICAL BEAVER’

heidi08 Attitudes towards beavers, BDA's, Beaver ecological impact February 11, 2022

The Walton foundation is committed to funding tools that monitor and create beaver dam analogues, although how they feel about the beavers themselves is anybodies guess.

How Mapping Beaver Wetlands Can Chart a Path to a Better Water Future

First-of-its kind project will use machine learning and remote sensing to track beaver wetland changes in the Colorado River Basin

At a time when climate change increasingly threatens water resources across the American West, what can we do to secure a future of sustainability rather than scarcity?

One promising way forward: Look to nature-based solutions from the past.

In the 16^th century, long before Europeans settled the continent, the North American beaver was the continent’s most diligent and effective water manager.

Beaver dams – millions of small-scale barriers of twigs, branches and mud – created ponds that acted like giant sponges on the landscape. They stored moisture and created complex wetlands that sustained diverse flora and fauna. They captured sediment and snowmelt that slowed floodwaters and – because they were imperfect and leaky – released water downstream in more even amounts throughout the year. (more…)

SCIENTIFIC AMERICAN PRAISES BEAVER DAMS

heidi08 BDA's, Beavers, Beavers and Fire Prevention, Beavers and fire runoff, Beavers and Forests February 9, 2022

Every now and then a beaver report emerges that is SO exactly what we need right now and SUCH very good news that I am torn between waving my beaver pompoms and cheering madly in the bleachers and stamping my foot in anger shouting SEE? IS THIS ENOUGH? Do you believe me now? Will you stop killing them now?

For the sake of brevity I’ll just do the first for now.

Beaver Dams Help Wildfire-Ravaged Ecosystems Recover Long after Flames Subside

Dams mop up debris that would otherwise kill fish and other downstream wildlife, new observations suggest

Oregon endured the third-largest wildfire in its recorded history last summer. The Bootleg Fire tore through the Upper Klamath Basin, an ecologically sensitive area that is home to multiple threatened and endangered species including the northern spotted owl and two fish—the koptu and c’waam (shortnose sucker and Lost River sucker)—that are culturally vital to the area’s Klamath Tribes. The fire left behind a charred landscape more than twice the size of New York City.

After the local fire season ended in autumn, Bill Tinniswood, a fisheries biologist with the Oregon Department of Fish and Wildlife, went out to survey the damage. Ash from the fire, which burned for more than a month, had clogged formerly pristine tributaries and turned them into black slurries. Thriving trout populations had disappeared, presumably choked to death by waterborne debris particles that deprived the fish of oxygen. “I was in total shock,” Tinniswood said. “It just looked like devastation.” (more…)

COULD I PLEASE JUST HAVE THE DAMS AND NOT THE BEAVERS?

heidi08 BDA's, Beaver ecological impact February 7, 2022

Well we had a great meeting. And it was good to see everyone. And I would say we’re definitely going to have a beaver festival this year…probably…and it will be either in June or in October…probably. Don’t you feel better having that all cleared up? I certainly do.

Now I don’t know how this slid by my beaver after christmas except to say it came out the exact day I was released from the hospital so maybe I had other things on my mind and my alerts weren’t very alert yet. But it’s a grand article and deserves our attention.