Want Healthy Floodplains and Streams? Want Clean Water? Then Make Room for the Beaver

I’m worried about the beaver.  Here’s why.

Imagine a network of brooks and rivulets meandering through a mosaic of shrubby, sometimes boggy, marshland, purifying water and absorbing high volumes of flow during storm events.  This was a typical low-gradient stream in the valleys of the Lower Susquehanna River Watershed in the days prior to the arrival of the trans-Atlantic human migrant.  Then, a frenzy of trapping, tree chopping, mill building, and stream channelization accompanied the east to west waves of settlement across the region.  The first casualty: the indispensable lowlands manager, the North American Beaver (Castor canadensis).

Beaver Traps
Nineteenth-century beaver traps on display in the collection of the State Museum of Pennsylvania in Harrisburg.  Soon after their arrival, Trans-Atlantic migrants (Europeans) established trade ties to the trans-Beringia migrants (“Indians”) already living in the lower Susquehanna valley and recruited them to cull the then-abundant North American Beavers.  By the early 1700s, beaver populations (as well as numbers of other “game” animals) were seriously depleted, prompting the Conoy, the last of the trans-Beringia migrants to reside on the lower Susquehanna, to disperse.  The traps pictured here are samples of the types which were subsequently used by the European settlers to eventually extirpate the North American Beaver from the Lower Susquehanna River Watershed during the 1800s.

Without the widespread presence of beavers, stream ecology quickly collapsed.  Pristine waterways were all at once gone, as were many of their floral and faunal inhabitants.  It was a streams-to-sewers saga completed in just one generation.  So, if we really want to restore our creeks and rivers, maybe we need to give the North American Beaver some space and respect.  After all, we as a species have yet to build an environmentally friendly dam and have yet to fully restore a wetland to its natural state.  The beaver is nature’s irreplaceable silt deposition engineer and could be called the 007 of wetland construction—doomed upon discovery, it must do its work without being noticed, but nobody does it better.

North American Beaver diorama on display in the State Museum of Pennsylvania in Harrisburg.
North American Beaver diorama on display in the State Museum of Pennsylvania in Harrisburg.  Beavers were reintroduced to the Susquehanna watershed during the second half of the twentieth century.
A beaver dam on a small stream in the Lower Susquehanna River Watershed.
A beaver dam and pond on a small stream in the Lower Susquehanna River Watershed.
Floodplain Wetlands Managed by North American Beavers
Beaver dams not only create ponds, they also maintain shallow water levels in adjacent areas of the floodplain creating highly-functional wetlands that grow the native plants used by the beaver for food.  These ecosystems absorb nutrients and sediments.  Prior to the arrival of humans, they created some of the only openings in the vast forests and maintained essential habitat for hundreds of species of plants as well as animals including fish, amphibians, reptiles, and birds.  Without the beaver, many of these species could not, and in their absence did not, exist here.
The beaver lodge provides shelter from the elements and predators for a family of North American Beavers.
Their newly constructed lodge provides shelter from the elements and from predators for a family of North American Beavers.
Sandhill Cranes Visit a Beaver-managed Floodplain in the lower Susquehanna valley
Floodplains managed by North American Beavers can provide opportunities for the recovery of the uncommon, rare, and extirpated species that once inhabited the network of streamside wetlands that stretched for hundreds of miles along the waterways of the Lower Susquehanna River Watershed.
Great Blue Heron
A wintering Great Blue Heron is attracted to a beaver pond by the abundance of fish in the rivulets that meander through its attached wetlands.
Sora Rail in Beaver Pond
Beaver Ponds and their attached wetlands provide nesting habitat for uncommon birds like this Sora rail.
Wood Duck feeding on Lesser Duckweed in Beaver Pond
Lesser Duckweed grows in abundance in beaver ponds and Wood Ducks are particularly fond of it during their nesting cycle.
Sandhill Cranes feeding among Woolgrass in a Beaver Pond
Beaver dams maintain areas of wet soil along the margins of the pond where plants like Woolgrass sequester nutrients and contain runoff while providing habitat for animals ranging in size from tiny insects to these rare visitors, a pair of Sandhill Cranes (Antigone canadensis).
Sandhill Cranes feeding among Woolgrass in a floodplain maintained by North American Beavers.
Sandhill Cranes feeding among Woolgrass in a floodplain maintained by North American Beavers.

Few landowners are receptive to the arrival of North American Beavers as guests or neighbors.  This is indeed unfortunate.  Upon discovery, beavers, like wolves, coyotes, sharks, spiders, snakes, and so many other animals, evoke an irrational negative response from the majority of people.  This too is quite unfortunate, and foolish.

North American Beavers spend their lives and construct their dams, ponds, and lodges exclusively within floodplains—lands that are going to flood.  Their existence should create no conflict with the day to day business of human beings.  But humans can’t resist encroachment into beaver territory.  Because they lack any basic understanding of floodplain function, people look at these indispensable lowlands as something that must be eliminated in the name of progress.  They’ll fill them with soil, stone, rock, asphalt, concrete, and all kinds of debris.  You name it, they’ll dump it.  It’s an ill-fated effort to eliminate these vital areas and the high waters that occasionally inundate them.  Having the audacity to believe that the threat of flooding has been mitigated, buildings and poorly engineered roads and bridges are constructed in these “reclaimed lands”.  Much of the Lower Susquehanna River Watershed has now been subjected to over three hundred years-worth of these “improvements” within spaces that are and will remain—floodplains.  Face it folks, they’re going to flood, no matter what we do to try to stop it.  And as a matter of fact, the more junk we put into them, the more we displace flood waters into areas that otherwise would not have been impacted!  It’s absolute madness.

By now we should know that floodplains are going to flood.  And by now we should know that the impacts of flooding are costly where poor municipal planning and negligent civil engineering have been the norm for decades and decades.  So aren’t we tired of hearing the endless squawking that goes on every time we get more than an inch of rain?  Imagine the difference it would make if we backed out and turned over just one quarter or, better yet, one half of the mileage along streams in the Lower Susquehanna River Watershed to North American Beavers.  No more mowing, plowing, grazing, dumping, paving, spraying, or building—just leave it to the beavers.  Think of the improvements they would make to floodplain function, water quality, and much-needed wildlife habitat.  Could you do it?  Could you overcome the typical emotional response to beavers arriving on your property and instead of issuing a death warrant, welcome them as the talented engineers they are?  I’ll bet you could.

The Value of Water

Are you worried about your well running dry this summer?  Are you wondering if your public water supply is going to implement use restrictions in coming months?  If we do suddenly enter a wet spell again, are you concerned about losing valuable rainfall to flooding?  A sensible person should be curious about these issues, but here in the Lower Susquehanna River Watershed, we tend to take for granted the water we use on a daily basis.

This Wednesday, June 7,  you can learn more about the numerous measures we can take, both individually and as a community, to recharge our aquifers while at the same time improving water quality and wildlife habitat in and around our streams and rivers.  From 5:30 to 8:00 P.M., the Chiques Creek Watershed Alliance will be hosting its annual Watershed Expo at the Manheim Farm Show grounds adjacent to the Manheim Central High School in Lancaster County.  According to the organization’s web page, more than twenty organizations will be there with displays featuring conservation, aquatic wildlife, stream restoration, Honey Bees, and much more.  There will be games and custom-made fish-print t-shirts for the youngsters, plus music to relax by for those a little older.  Look for rain barrel painting and a rain barrel giveaway.  And you’ll like this—admission and ice cream are free.  Vendors including food trucks will be onsite preparing fare for sale.

And there’s much more.

To help recharge groundwater supplies, you can learn how to infiltrate stormwater from your downspouts, parking area, or driveway…

Urban Runoff
Does your local stream flood every time there’s a downpour, then sometimes dry up during the heat of summer?  Has this problem gotten worse over the years?  If so, you may be in big trouble during a drought.  Loss of base flow in a stream or river is a sure sign of depleted groundwater levels in at least a portion of its drainage basin.  Landowners, both public and private, in such a watershed need to start infiltrating stormwater into the ground instead of allowing it to become surface runoff.
Rain Garden Model
You can direct the stormwater from your downspout, parking area, or driveway into a rain garden to help recharge the aquifer that supplies your private or public well and nearby natural springs.  Displays including this model provided by Rapho Township show you how.

…there will be a tour of a comprehensive stream and floodplain rehabilitation project in Manheim Memorial Park adjacent to the fair grounds…

Legacy Sediments
Have you seen banks like these on your local stream?  On waterways throughout the Lower Susquehanna River Watershed, mill dams have trapped accumulations of sediments that eroded from farm fields prior to the implementation of soil conservation practices.  These legacy sediments channelize creeks and disconnect them from their now buried floodplains.  During storms, water that would have been absorbed by the floodplain is now displaced into areas of higher ground not historically inundated by a similar event.
Adjacent to the Manheim Farm Show grounds, the Chiques Creek Stream Restoration Project in Manheim Memorial Park has reconnected the waterway to its historic floodplain by removing a dam and the legacy sediments that accumulated behind it.
Legacy Sediments Removed
Chiques Creek in Manheim following removal of hundreds of truck loads of legacy sediments.  High water can again be absorbed by the wetlands and riparian forest of the floodplain surrounding this segment of stream.  There are no incised banks creating an unnatural channel or crumbling away to pollute downstream waters with nutrients and sediment.  Projects similar to this are critical to improving water quality in both the Susquehanna River and Chesapeake Bay.  Closer to home, they can help municipalities meet their stormwater management (MS4) requirements.
Bank-full Bench
Mark Metzler of Rettew Associates guides a tour of the Chiques Creek rehabilitation.  Here, cross vanes, stone structures that provide grade control along the stream’s course, were installed to gently steer the center of the channel away from existing structures.   Cross vanes manipulate the velocity of the creek’s flow across its breadth to dissipate potentially erosive energy and more precisely direct the deposition of gravel and sediment.

…and a highlight of the evening will be using an electrofishing apparatus to collect a sample of the fish now populating the rehabilitated segment of stream…

Electrofishing
Matt Kofroth, Lancaster County Conservation District Watershed Specialist, operates a backpack electrofishing apparatus while the netting crew prepares to capture the temporarily stunned specimens.  The catch is then brought to shore for identification and counting.

…so don’t miss it.  We can hardly wait to see you there!

The 2023 Watershed Expo is part of Lancaster Conservancy Water Week.

Forty Years Ago in the Lower Rio Grande Valley: Day Seven


Back in late May of 1983, four members of the Lancaster County Bird Club—Russ Markert, Harold Morrrin, Steve Santner, and your editor—embarked on an energetic trip to find, observe, and photograph birds in the Lower Rio Grande Valley of Texas.  What follows is a daily account of that two-week-long expedition.  Notes logged by Markert some four decades ago are quoted in italics.  The images are scans of 35 mm color slide photographs taken along the way by your editor.


DAY SEVEN—May 27, 1983

“Bentsen State Park”

“6 A.M. alarm rang.  After breakfast we walked an hour or more.  At 8:15 we phoned Father Tom for more information.  We next went back to Anzalduas County Park in hopes of seeing a Hook-billed Kite.  It is now 11:30 and NO luck.  Steve got his first lifer — Red-billed Pigeon.  We parked on a dirt dike and they went walking.  I took a nap.”

Based on new tips from Father Tom, we had back-tracked east along the Rio Grande to look for Hook-billed Kite, Red-billed Pigeon (Patagioenas flavirostris), and other species before continuing west toward Falcon Dam in coming days.  The pigeon was yet another specialty with a range that extends north from Central America into the subtropical riparian forests of the Lower Rio Grande Valley.

Anzalduas County Park is located along the Rio Grande at the Anzalduas Diversion Dam, part of a network of flood control projects initiated in the 1930s to reign in the “untamed river”.  Construction on this particular dam began in 1956 and was completed in 1960.  Operation of diversion and flood control dams on the Rio Grande has functionally eliminated stream meander along its present course, thus the delta that is the Lower Rio Grande Valley will cease to experience the morphological changes that create wetlands, resacas, and other natural features in the floodplain.  Thought to be excellent ideas at the time, most of these projects were based on a blurred vision of the connection between streams, their floodplains, and the watershed’s aquifer.  This condition has manifested itself as a blindness to the finite nature of water supplies, particular where consumption rates are still sharply rising while groundwater recharge is diminishing.

Anzalduas Diversion Dam and Interior Floodway System
The Anzalduas Diversion Dam redirects water from the Rio Grande to supply an irrigation canal on the Mexico side of the river.  In addition, the Anzalduas Reservoir supplies domestic water for Reynosa, Matamoros, and other towns south of the border.  To control flooding on the river downstream, a spillway on the north side of the reservoir created by the dam diverts high water into a seventy-mile-long dike-lined interior floodway that discharges the excess flow into the Gulf of Mexico.  A portion of the floodway utilizes the channel of the Arroyo Colorado through the Harlingen area.  On the map, irrigated lands are shaded green and urban space is yellow.  (International Boundary Water Commission-United States Section base image)

In addition to the Red-billed Pigeon, we found Brown-headed Cowbirds at Anzalduas County Park.  Flying over the adjacent reservoir/river there were Caspian Terns.  We identified some turtles too—Red-eared Sliders.

Back in 1983, we saw very few people in any of the parks or refuges along the Rio Grande.  From atop the flood control levee, I photographed this lone rider having a look around the interior floodway adjacent to Anzalduas County Park.  Today, this area is at times bustling with border patrol activity that includes the use of armored vehicles and mounted officers.  Shallow waters on the downstream side of the dam provide a busy crossing point for migrants and smugglers and the park itself was used as a migrant camp during the SARS-CoV-2 outbreak.  Border barrier design follows the levee as well as parts of the interior floodway itself.  As a result, many of these parks and refuges will be bisected or left entirely on the south side of the wall, a “no man’s land ” between it and the river.

“After my nap, I took pictures of the place and of the men coming back.  Then to the McAllen Sewage Ponds where we had some luck — Eared Grebe and others.”

The McAllen Sewage Ponds were like a little oasis for waterbirds.  Though not a specialty of the Lower Rio Grande Valley, the Eared Grebe (Podiceps nigricollis) was a western species we were happy to have seen.  A Gulf Coast species, Mottled Duck (Anas fulvigula), was another welcome find.  Other sightings included Least Grebe, 100 Ruddy Ducks, Northern Shoveler, Mallard, Black-bellied Whistling Duck, American Coot, Common Gallinule, Spotted Sandpiper, White-faced Ibis (Plegadis chihi), Black-necked Stilt, Franklin’s Gull, Least Tern (Sternula antillarum), Scissor-tailed Flycatcher, Great-tailed Grackle, and Bronzed Cowbird.

Swimming around in the McAllen Sewage Ponds was a Nutria (Myocastor coypus), also known as the Coypu, a mammal resembling a giant muskrat—remember, things really are bigger in Texas.

“Next to the Time Out  Camp Ground to check with a couple I met in February.  They had moved, their space was empty.  Back to Bentsen State Park.  On the way we bought a watermelon for supper’s dessert.  Rain almost all P.M.  Raining now 8:00 P.M.  Before supper we checked again for the Tropical Parula with no luck.  The watermelon was very good for dessert.”

Details received this morning from Father Tom suggested we check the area of the Bentsen Rio Grande Valley State Park campground near a large Spanish Moss-draped tree for the nesting Tropical Parulas.  I don’t recall what kind of tree it was, but the paved road circled the area surrounding it indicating that those who had designed the campground had purposely preserved this massive specimen as something unique.  Despite its prominence, no sights or sounds of the Tropical Parulas were found.  We reached the conclusion that we were a little late; they were gone for the year.  To soothe our sorrows, we ate watermelon—very refreshing!

Forty Years Ago in the Lower Rio Grande Valley: Day Four


Back in late May of 1983, four members of the Lancaster County Bird Club—Russ Markert, Harold Morrrin, Steve Santner, and your editor—embarked on an energetic trip to find, observe, and photograph birds in the Lower Rio Grande Valley of Texas.  What follows is a daily account of that two-week-long expedition.  Notes logged by Markert some four decades ago are quoted in italics.  The images are scans of 35 mm color slide photographs taken along the way by your editor.


DAY FOUR—May 24, 1983

“AOK Campground—South of Kingsville, Texas”

“Arose at 6:30 A.M. to the tune of Common Nighthawks.  After breakfast, we headed for Harlingen.  While driving south we saw six pairs of Black-bellied Whistling Ducks.  At Harlingen we phoned Father Tom, who is an expert birder for the area.”

As we drove south to Harlingen, much our 100-mile route was through the Laureles division of the King Ranch, the largest ranch in the United States.  It covers over 800,000 acres and is larger than the state of Rhode Island.  The road there was as straight as an arrow with wire fences on both sides and scrubland as far as the eye could see.  Things really are bigger in Texas.

Once in Harlingen, we did two things no one needs to do anymore:

      1.   Find a coin-operated telephone to place a call to Father Tom.
      2.   Ask Father Tom for the latest tips on the locations of rare and/or target birds.

Today, nearly everyone traveling such distances to find birds is carrying a cellular phone and many can use theirs to access internet sites and databases such as eBird to get current sighting information.  Back in 1983, Father Tom Pincelli was a dear friend to birders visiting the Lower Rio Grande Valley.  Few places had a person who was willing to answer the phone and field inquiries regarding the latest whereabouts of this or that bird.  To remain current, he also had to religiously (forgive me for the pun) collect sighting information from the observers with whom he had contact.  For locations elsewhere across the country, a birder in 1983 was happy just to have a phone number for a hotline with a tape-recorded message listing the unusual sightings for its covered region.  If you were lucky, the volunteer logging the sightings would be able to update the tape once a week.  For those who dialed his number, Father Tom provided an exceptionally personal experience.

Since 1983, Father Tom Pincelli, also known as “Father Bird”, has tirelessly promoted birding and conservation throughout the Lower Rio Grande Valley.  His efforts have included hosting a P.B.S. television program and writing columns for local newspapers.  He has been instrumental in developing the annual Rio Grande Valley Birding Festival.  The public sentiment he has generated for the birding paradise that is the Lower Rio Grande Valley has helped facilitate the acquisition and/or protection of many key parcels of land in the region.

“After receiving information on locations of Tropical Parula, Ferruginous Pygmy Owl, Hook-billed Kite, Brown Jay, and Clay-colored Robin, we went on to check out the Brownsville Airport where we will meet Harold and Steve Thursday noon.”

If we were going to see these five species in the American Birding Association listing area, then we would have to see them in the Lower Rio Grande Valley.  All five were target birds for each of us, including Harold who had few other possibilities for new species on the trip.  Father Tom provided us with tips for finding each.

I noticed as we began moving around Harlingen and Brownsville that Russ was swiftly getting his bearings—he had been here before and was starting to remember where things were.  His ability to navigate his way around allowed us to keep moving and see a lot in a short time.

In Harlingen, we easily found Mourning Doves and the non-native Rock Pigeons, species we see regularly in Pennsylvania.  We became more enthusiastic about doves and pigeons soon after when we saw the first of the several other species native to south Texas, the diminutive Inca Dove (Columbina inca), also known as the Mexican Dove.

“Next, to the Brownsville Dump to see the White-necked Ravens — Then to Mrs. Benn’s in Brownsville for the Buff-bellied Hummingbird.  Both lifers for Larry.”

For birders wanting to see a White-necked Raven in the Lower Rio Grande Valley, the Brownsville Dump was the place to go.  With very little effort—excluding a trip of nearly 2,000 miles to get there—we found them.  Today, birders still go to the Brownsville Dump to find White-necked Ravens, though the dump is now called the Brownsville Landfill and the bird is known as the Chihuahuan Raven (Corvus cryptoleucus).

Mrs. Benn’s home was in a verdant residential neighborhood in Brownsville.  She welcomed birders to come and see the Buff-bellied Hummingbirds that visited her feeder filled with sugar water.  I don’t recall whether or not she kept a guest book for visitors to sign, but if she did, it would have included hundreds—maybe thousands—of names of people from all over North America who came to her garden to get a look at a Buff-bellied Hummingbird.  After arriving, we waited a short time and sure enough, we watched a Buff-bellied Hummingbird (Amazilia yucatanensis) sipping Mrs. Benn’s home-brewed nectar from her glass feeder.  This emerald hummingbird is primarily a Mexican species with a breeding range that extends north into the Lower Rio Grande Valley of Texas.  When not breeding, a few will wander north and east along the Gulf Coastal Plain as far as Florida.

Other finds at Mrs Benn’s included White-winged Dove (Zenaida asiatica), Ash-throated Flycatcher (Myiarchus cinerascens), Brown-crested Flycatcher (Myiarchus tyrannulus), and Black-crested Titmouse (Baeolophus atricristatus), a species also known as Mexican Titmouse.

White-winged Dove
We identified this White-winged Dove at Mrs. Benn’s house in Brownsville.
Green Anole
In Mrs. Benn’s lush subtropical garden beneath a canopy of tall trees we found this male Green Anole (Anolis carolinensis) displaying its red throat patch.  (Vintage 35 mm image)

The Lower Rio Grande Valley from Rio Grande City east to the Gulf of Mexico is actually the river’s outflow delta.  At least six historic channels have been delineated in Texas on the north side of the river’s present-day course.  An equal number may exist south of the border in Mexico.  Hundreds of oxbow lakes known as “resacas” mark the paths of the former channels through the delta.  Many resacas are the centerpieces of parks, wildlife refuges, and housing developments.  Still others are barely detectable after being buried in silt deposits left by the meandering river.  Channelization, land disturbances related to agriculture, and a boom in urbanization throughout the valley have disconnected many of the most recently formed resacas from the river’s floodplain, preventing them from absorbing the impact of high-water events.  These alterations to natural morphology can severely aggravate flooding and water pollution problems.

The Lower Rio Grande Valley
The Lower Rio Grande Valley is the site of a boom in urbanization.  Undeveloped private holdings and government lands including numerous parks and refuges provide sanctuary for some of the valley’s unique wildlife.  The parcels colored dark blue on the map are units of the Lower Rio Grande Valley National Wildlife Refuge.  (United States Fish and Wildlife Service base image)

“On to Santa Ana National Wildlife Refuge.  We walked to Pintail Lake and saw 6 Black-bellied Whistling Ducks and 2 Mississippi Kites and 1 Pied-billed Grebe.  We drove the route thru the park with great results—Anhingas, Least Grebe, and more Black-bellied Whistling Ducks.

Santa Ana National Wildlife Refuge on the Rio Grande is not only a birder’s mecca, 300 species of butterflies have been identified there.  That’s half the species known to occur in the United States!  Its subtropical riparian forest and resaca lakes provide habitat for hundreds of migratory and resident bird species including many Central and South American species that reach the northern limit of their range in the Lower Rio Grande Valley.  Two endangered cats occur in the park—the Ocelot (Leopardus pardalis) and the Jaguarundi  (Herpailurus yagouaroundi).

Ocelot
In the Lower Rio Grande Valley, the secretive Ocelot, like the Jaguarundi, is at the northern limit of its eastern range. Time will tell how urban development including construction of the border wall will impact the distribution and survival of these and other terrestrial species there.  (A modern digital image)
Jaguarundi
Jaguarundi.  (United States Fish and Wildlife Service image)

We saw no cats at Santa Ana, but did quite well with the birds.  Our list included the species listed above plus Cattle Egret (Bubulcus ibis); Louisiana Heron, now known as Tricolored Heron (Egretta tricolor); Plain Chachalacas; Purple Gallinule; Common Gallinule (Gallinula galeata); American Coot; Killdeer; Greater Yellowlegs; the coastal Laughing Gull (Leucophaeus atricilla); and its close relative of the central flyway and continental interior, the Franklin’s Gull (Leucophaeus pipixcan).  Others finds were White-winged Dove, Mourning Dove, Inca Dove, Yellow-billed Cuckoo, Golden-fronted Woodpecker, Ladder-backed Woodpecker (Dryobates scalaris), Brown-crested Flycatcher, Altamira Oriole, Great-tailed Grackle, and House Sparrow.  A real standout was the colorful Green Jay (Cyanocorax luxosus), yet another tropical Central American species found north only as far as the Lower Rio Grande Valley.

Mississippi Kite
During spring (April-May) and fall (August-September), Mississippi Kites migrate by the thousands through the skies of the Lower Rio Grande Valley.  Both Santa Ana and nearby Bentsen-Rio Grande State Park have hosted formal hawk counts in recent years.  (Vintage 35 mm image)
Black-necked Stilt
A Black-necked Stilt at Santa Ana N.W.R.  (Vintage 35 mm image)
Least Grebe
A Least Grebe (Tachybaptus dominicus) with young in a man-made canal that mimics flooded resaca habitat at Santa Ana National Wildlife Refuge.  (Vintage 35 mm image)
Black-bellied Whistling Ducks at Santa Ana National Wildlife Refuge
Black-bellied Whistling Ducks take off from a pond at Santa Ana National Wildlife Refuge.  (Vintage 35 mm image)
Altamira Oriole
The spectacular colors of Altamira Orioles (Icterus gularis) dazzled us every time we saw them.  This was my first, seen soon after arriving at Santa Ana N.W.R. where the checklist still had the species listed under its former name, Lichtenstein’s Oriole. The Altamira Oriole ranges north of Mexico only into the Lower Rio Grande Valley.  (Vintage 35 mm image)

“We were unlucky not to find a campground at McAllen, so we went on to Bentsen State Park where we got a camp spot.  After a sauerkraut supper, we birded till dark, then showered and wrote up the log.  Very hot today.”

Bentsen-Rio Grande Valley State Park, like the Santa Ana National Wildlife Refuge, is located along the Rio Grande river and features dense subtropical riparian forest that grows in the naturally-deposited silt levees of the floodplain surrounding several lake-like oxbow resacas.  Montezuma Bald Cypress (Taxodium mucronatum) is a native specialty found there but nowhere north of the Lower Rio Grande Valley.  During our visit, we marveled at the epiphyte Spanish Moss (Tillandsia usneoides) adorning many of the more massive trees in the park.  Willows lined much of the river shoreline.

Over time, flood control projects such as man-made dams, drainage ditches, and levees have impaired stormwater capture and aquifer recharge in the floodplain.  These alterations to watershed hydrology have resulted in drier soils in many sections of the Lower Rio Grande Valley’s riparian forests.  Where drier conditions persist, xeric (dry soil) scrubland plants are slowly overtaking the moisture-dependent species.  As a result, the park’s woodlands are composed of trees with a variety of microclimatic requirements—Anaqua (Ehretia anacua), Cedar Elm (Ulmus crassifolia), Texas Ebony (Ebenopsis ebano), hackberry, mesquite, Mexican Ash (Fraxinus berlandieriana), retama, and tepeguaje are the principle species.  The park’s subtropical Texas Wild Olive (Cordia boissieri) grows in the wild nowhere north of the Lower Rio Grande Valley.

While a majority of birders visiting Benten-Rio Grande State Park come to see the more tropical specialties of the riparian woods, searching the brushy habitat of the park’s scrubland can afford one the opportunity to see species typical of the southwestern United States and deserts of Mexico.  This scrubland of the Lower Rio Grande Valley is part of the Tamaulipan Mezquital ecoregion, an area of xeric (dry soil) shrublands and deserts that extends northwest from the delta through most of south Texas and into the bordering provinces of northeastern Mexico.

Our campsite was located in prime birding habitat.  We were a short walk away from one of the park’s flooded oxbow resacas and vegetation was thick along the roadsides.  It was no surprise that the place abounded with birds.  An evening stroll yielded Plain Chachalaca, White-winged Dove, Mourning Dove, White-fronted Dove, Golden-fronted Woodpecker, Brown-crested Flycatcher, Green Jay, Altamira Oriole, Great-tailed Grackle, and Bronzed Cowbird (Molothrus aeneus).  At nightfall, we listened to the calls of an Eastern Screech Owl (Megascops asio), Common Nighthawks, and Common Pauraque (Nyctidromus albicollis), a nightjar of Central and South America that nests only as far north as the Lower Rio Grande Valley.  The Common Pauraque is the tropical counterpart of the Eastern Whip-poor-will, a Neotropical migrant that nests in scattered forest locations throughout eastern North America.

A Plain Chachalaca at Bentsen-Rio Grande Valley State Park.
The Plain Chachalaca (Ortalis vetula), a pheasant-like wildfowl of the dense riparian forest and scrubland at Bentsen-Rio Grande Valley State Park.  (Vintage 35 mm image)
Plain Chachalacas
Seldom did we see a Plain Chachalaca alone, there were always others nearby.  (Vintage 35 mm image)
White-fronted Dove
Like the chachalacas, this White-fronted Dove was attracted to some birdseed scattered on a big log behind our campsite.  This species is now known as White-tipped Dove (Leptotila verreauxi) and is at the northern tip of its range in the Lower Rio Grande Valley.

I would note that we saw no “snowbirds”—long-term vacationers from the northern states and Canada who fill the park through the cooler months of fall, winter, and spring.  They were gone for the summer.  But for a few other friendly folks, we had the entire campground to ourselves for the duration of our stay.

Photo of the Day

Legacy Sediment Removal and Floodplain Restoration
This stream restoration project is currently underway along a one-mile-long segment of Lancaster Conservancy lands along Conewago Creek.  The mountain of dirt is one of several stockpiles of legacy sediments removed to reestablish the floodplain’s historic geomorphology.  After eroding from cropland during the years prior to soil conservation, legacy sediments accumulated behind mill dams on waterways throughout the lower Susquehanna watershed.  After removal of the dams, creeks were left trapped within the sediment-choked bottomlands, incising steep muddy banks as they cut a new path through the former mill ponds.  Excavating legacy sediments from these sites eliminates creek banks and allows floodwaters to again spill directly into wetlands along the stream course.  With floodplain and wetland functions restored, nutrients are sequestered, high water is infiltrated to recharge aquifers, sediment loads from collapsing banks are eliminated, and much-needed habitat is created for native plants and animals.

To learn more about this project and others, you’ll want to check out the Landstudies website.

Take a Look at My Mussels

At this very moment, your editor is comfortably numb and is, if everything is going according to plans, again having a snake run through the plumbing in his body’s most important muscle.  It thus occurs to him how strange it is that with muscles as run down and faulty as his, people at one time asked him to come speak about and display his marvelous mussels.  And some, believe it or not, actually took interest in such a thing.  If the reader finds this odd, he or she would not be alone.  But the peculiarities don’t stop there.  The reader may find further bewilderment after being informed that the editor’s mussels are now in the collection of a regional museum where they are preserved for study by qualified persons with scientific proclivities.  All of this show and tell was for just one purpose—to raise appreciation and sentiment for our mussels, so that they might be protected.

Click on the “Freshwater Mussels and Clams” tab at the top of this page to see the editor’s mussels, and many others as well.  Then maybe you too will want to flex your muscles for our mussels.  They really do need, and deserve, our help.

We’ll be back soon.

Put Up the White Flag

It was a routine occurrence in many communities along tributaries of the lower Susquehanna River during the most recent two months.  The rain falls like it’s never going to stop—inches an hour.  Soon there is flash flooding along creeks and streams.  Roads are quickly inundated.  Inevitably, there are motorists caught in the rising waters and emergency crews are summoned to retrieve the victims.  When the action settles, sets of saw horses are brought to the scene to barricade the road until waters recede.  At certain flood-prone locations, these events are repeated time and again.  The police, fire, and Emergency Medical Services crews seem to visit them during every torrential storm—rain, rescue, rinse, and repeat.

We treat our local streams and creeks like open sewers.  Think about it.  We don’t want rainwater accumulating on our properties.  We pipe it away and grade the field, lawn, and pavement to roll it into the neighbor’s lot or into the street—or directly into the waterway.  It drops upon us as pure water and we instantly pollute it.  It’s a method of diluting all the junk we’ve spread out in its path since the last time it rained.  A thunderstorm is the big flush.  We don’t seem too concerned about the litter, fertilizer, pesticides, motor fluids, and other consumer waste it takes along with it.  Out of sight, out of mind.

Failure to retain and infiltrate stormwater to recharge aquifers can later result in well failures and reduced base flow in streams.  (Conoy Creek’s dry streambed in June, 2007)

Perhaps our lack of respect for streams and creeks is the source of our complete ignorance of the function of floodplains.

Floodplains are formed over time as hydraulic forces erode bedrock and soils surrounding a stream to create adequate space to pass flood waters.  As floodplains mature they become large enough to reduce flood water velocity and erosion energy.  They then function to retain, infiltrate, and evaporate the surplus water from flood events.  Microorganisms, plants, and other life forms found in floodplain wetlands, forests, and grasslands purify the water and break down naturally-occurring organic matter.  Floodplains are the shock-absorber between us and our waterways.  And they’re our largest water treatment facilities.

Why is it then, that whenever a floodplain floods, we seem motivated to do something to fix this error of nature?  Man can’t help himself.  He has a compulsion to fill the floodplain with any contrivance he can come up with.  We dump, pile, fill, pave, pour, form, and build, then build some more.  At some point, someone notices a stream in the midst of our new creation.  Now it’s polluted and whenever it storms, the darn thing floods into our stuff—worse than ever before.  So the project is crowned by another round of dumping, forming, pouring, and building to channelize the stream.  Done!  Now let’s move all our stuff into our new habitable space.

Natural Floodplain- Over a period of hundreds or thousands of years, the stream (dark blue) has established a natural floodplain including wetlands and forest.  In this example, buildings and infrastructure are located outside the zone inundated by high water (light blue) allowing the floodplain to function as an effective water-absorbing buffer.
Impaired Floodplain- Here the natural floodplain has been filled for building (left) and paved for recreation area parking (right).  The stream has been channelized.  Flood water (light blue) displaced by these alterations is likely to inundate areas not previously impacted by similar events.  Additionally, the interference with natural flow will create new erosion points that could seriously damage older infrastructure and properties.

The majority of the towns in the lower Susquehanna valley with streams passing through them have impaired floodplains.  In many, the older sections of the town are built on filled floodplain.  Some new subdivisions highlight streamside lawns as a sales feature—plenty of room for stockpiling your accoutrements of suburban life.  And yes, some new homes are still being built in floodplains.

When high water comes, it drags tons of debris with it.  The limbs, leaves, twigs, and trees are broken down by natural processes over time.  Nature has mechanisms to quickly cope with these organics.  Man’s consumer rubbish is another matter.  As the plant material decays, the embedded man-made items, particularly metals, treated lumber, plastics, Styrofoam, and glass, become more evident as an ever-accumulating “garbage soil” in the natural floodplains downstream of these impaired areas.  With each storm, some of this mess floats away again to move ever closer to Chesapeake Bay and the Atlantic.  Are you following me?  That’s our junk from the curb, lawn, highway, or parking lot bobbing around in the world’s oceans.

A shed, mobile home, or house can be inundated or swept away during a flood.  Everything inside (household chemicals, gasoline, fuel oil, pesticides, insulation, all those plastics, etc.) instantly pollutes the water.  Many communities that rely on the Susquehanna River for drinking water are immediately impacted, including Lancaster, PA and Baltimore, MD.  This dumpster was swept away from a parking lot in a floodplain.  It rolled in the current, chipping away at the bridge before spilling the rubbish into the muddy water.  After the flood receded, the dumpster was found a mile downstream.  Its contents are still out there somewhere.
Floodplains along the lower Susquehanna River are blanketed with a layer of flotsam that settles in place as high water recedes.  These fresh piles can be several feet deep and stretch for miles.  Nature decomposes the organic twigs and driftwood to build soil-enriching humus.  However, the plastics and other man-made materials that do not readily decay or do not float away toward the sea during the next flood are incorporated into the alluvium and humus creating a “garbage soil”.  Over time, the action of abrasives in the soil will grind small particles of plastics from the larger pieces.  These tiny plastics can become suspended in the water column each time the river floods.  What will be the long-term impact of this type of pollution?
Anything can be swept away by the powerful hydraulic forces of flowing water.  Large objects like this utility trailer can block passages through bridges and escalate flooding problems.
The cost of removing debris often falls upon local government and is shared by taxpayers.
Here, a junked boat dock is snagged on the crest of the York Haven Dam at Conewago Falls.  Rising water eventually carried it over the dam and into the falls where it broke up.  This and tons of other junk are often removed downstream at the Safe Harbor Dam to prevent damage to turbine equipment.  During periods of high water, the utility hauls debris by the truck-load to the local waste authority for disposal.  For the owners of garbage like this dock, it’s gone and it’s somebody else’s problem now.
Motor vehicles found after floating away from parking areas in floodplains can create a dangerous dilemma for police, fire, and E.M.S. personnel, particularly when no one witnesses the event.  Was someone driving this car or was it vacant when it was swept downstream?  Should crews be put at risk to locate possible victims?

Beginning in 1968, participating municipalities, in exchange for having coverage provided to their qualified residents under the National Flood Insurance Program, were required to adopt and enforce a floodplain management ordinance.  The program was intended to reduce flood damage and provide flood assistance funded with premiums paid by potential victims.  The program now operates with a debt incurred during severe hurricanes.  Occurrences of repetitive damage claims and accusations that the program provides an incentive for rebuilding in floodplains have made the National Flood Insurance Program controversial.

In the Lower Susquehanna River Watershed there are municipalities that still permit new construction in floodplains.  Others are quite proactive at eliminating new construction in flood-prone zones, and some are working to have buildings removed that are subjected to repeated flooding.

Another Wall— Here’s an example of greed by the owner, engineer, and municipality… placing their financial interests first.  The entire floodplain on the north side of this stream was filled, then the wall was erected to contain the material.  A financial institution’s office and parking lot was constructed atop the mound.  This project has channelized the stream and completely displaced half of the floodplain to a height of 15 to 20 feet.  Constructed less than five years ago, the wall failed already and has just been totally reconstructed.  The photo reveals how recent flooding has begun a new erosion regime where energy is focused along the base of the wall.  Impairment of a floodplain to this degree can lead to flooding upstream of the site and erosion damage to neighboring infrastructure including roads and bridges.
The floodplain along this segment of the lower Swatara Creek in Londonderry Township, Dauphin County is free to flood.  Ordinances prohibit new construction here and 14 older houses that repeatedly flooded were purchased, dismantled, and removed using funding from the Federal Emergency Management Agency (F.E.M.A).  A riparian buffer was planted and some wetland restorations were incorporated into stormwater management installations along the local highways.  When the waters of the Swatara rise, the local municipality closes the roads into the floodplain.  Nobody lives or works there anymore, so no one has any reason to enter.  There’s no need to rescue stubborn residents who refused advice to evacuate.  Sightseers can park and stand on the hill behind the barricades and take all the photographs they like.
A new Pennsylvania Turnpike bridge across Swatara Creek features wide passage for the stream below.  Water flowing in the floodplain can pass under the bridge without being channelized toward the path where the stream normally flows in the center.  The black asterisk-shaped floats spin on the poles to help deflect debris away from the bridge piers.  (flood crest on July 26, 2018)
People are curious when a waterway floods and they want to see it for themselves.  Wouldn’t it be wise to anticipate this demand for access by being ready to accommodate these citizens safely?  Isn’t a parking lot, picnic area, or manicured park safer and more usable when overlooking the floodplain as opposed to being located in it?  Wouldn’t it be a more prudent long-term investment, both financially and ecologically, to develop these improvements on higher ground outside of flood zones?
Now would be a good time to stop the new construction and the rebuilding in floodplains.  Aren’t the risks posed to human life, water quality, essential infrastructure, private property, and ecosystems too great to continue?
Isn’t it time to put up the white flag and surrender the floodplains to the floods?  That’s why they’re there.  Floodplains are for flooding.