Mending the Carpet
10/14/21
Hello everyone:
This week in curated Anthropocene news, I have three recommendations:
1. Read Anthony Doerr’s beautiful short essay in Orion on the Hubble Ultra Deep Field image as a reminder that Earth’s unimportance in the universe makes it all the more important to its inhabitants in a time of self-inflicted planetary disruption.
2. Become a green shareholder and join an effort to reform the oil industry from within, via “climate-friendly shareholder rebellions.” It’s like the martial arts axiom of “move the head and the body will follow,” where the board is the head and the corporation is the body. Here’s a Mother Jones interview with Mark van Baal of Follow This.
3. Beef production emits five times the CO2 of air travel, and 3.5 times as much as Japan. Check out this graphic from the Economist, and read the article.
Enjoy. Now on to the final installment of my essay on road ecology and wildlife crossings.
There is a classic metaphor from David Quammen in his 1996 book Song of the Dodo about the problem of habitat fragmentation. Imagine a fine Persian carpet, he says, and now imagine taking a very sharp knife (a fine metaphor for our linear infrastructure…) and cutting it up into 36 equal pieces.
The severing fibers release small tweaky noises, like the muted yelps of outraged Persian weavers. Never mind the weavers. When we’re finished cutting, we measure the individual pieces, total them up – and find that, lo, there’s still nearly 216 square feet of recognizably carpetlike stuff. But what does it amount to? Have we got thirty-six nice Persian throw rugs? No. All we’re left with is three dozen ragged fragments, each one worthless and commencing to come apart.
Welcome to habitat in the Anthropocene. Imagine each of those cuts in the carpet as the roads you drive on, and the roads that wildlife needs to cross. Put up guardrails and fencing around many of the cuts, and watch animals find the weak points that will lead them onto the road and then either to the other side or to the Other Side. Fill many of the cut squares with houses and malls and parking lots and landfills, and watch those habitat fragments become more ragged. Some species – usually small ones, with small ranges – do better than others. But we’re so out of touch with what large-scale healthy habitat looks and feels like that we don’t really notice. As far as we know, the woods are the woods, however thin between our house and the next. We live in fragments but think of it as carpet.
Habitat connectivity in the east, particularly in New England, is not often about linking large landscapes to each other, or at least not on the scale of Wyoming and Montana, and it’s not often about migrating species. It’s more often about allowing moose and wood frogs to move to the pond or vernal pool of their heart’s desire. It’s about providing safe wandering for all the usual suspects – deer, skunk, possum, squirrel, fox, turtle, to name a few – through an interrupted forest or wetland. It’s about re-establishing fish passage past dams (or by removing the dams) and replacing thousands of culverts thrown in decades ago without regard for the movement of other species.
The good news is that in the highly fragmented, small-scale landscapes of the east, the principles of road ecology and wildlife crossing design still apply. If there are stretches of road known for wildlife collisions, or if there are particularly threatened species clustered in specific areas, or if there are seasons of high mortality, then there are solutions which can be put into place. Fencing and crossing will work in many cases, even if not built on the scale seen out west. Perhaps the largest scale project in the east is in Florida, where sixty underpass crossings built or modified for endangered panthers have significantly reduced collisions.
But projects in the east mostly consist of improving fencing and modifying existing culverts or the terrain under bridges to make them attractive options for local species. Most of this work occurs when a road or highway is being updated for other reasons. Maine has done well in this regard. A decade ago, a broad consortium of organizations (Maine Audubon, The Nature Conservancy, Natural Resources Council of Maine, state and federal agencies, and several more) conspired to create the Stream Smart program, which has now assessed nearly every stream crossing in the state for its capacity to allow terrestrial or aquatic wildlife passage (it turns out that about 90% of them make passage difficult or impossible at least part of the year). That information is essential to state planners looking to improve roads and passage at the same time. And it’s vital in a state where water is at the center of wildlife movement: 85% of Maine’s vertebrates live in or use wetlands, ponds, or rivers at least part of the year. The “golden rule” of the Stream Smart program is really two rules: “Let the stream act like a stream,” and “Make the road invisible to the stream.”
Sometimes a state responds to outcry from citizens who refuse to watch helplessly as collisions happen repeatedly in the same place. A great example of this is when frogs and salamanders come out en masse during the first warm, rainy night in spring – known as Big Night – to plod toward the nearest vernal pool. A citizen initiative in Vermont in 2016 led to some very successful frog/salamander tunnels. Likewise, several turtle tunnels were constructed in New Jersey.
The bad news is that there will still be lots of carnage. 89% of wildlife collisions in the U.S. occur on two-lane roads, and while these are narrow enough that an underpass is relatively affordable, there are millions of miles to assess for that necessity. Unless there is a radical rethinking of our roads and vehicles, the simple, heartbreaking truth is that even in what may be heady times for the construction of wildlife crossings, much of what we will do is triage for the most vulnerable species in the most vulnerable places.
Looking ahead to the extraordinary turbulence of this century, the future of wildlife crossings in a changing climate will be complicated, like everything else. How will the habitats we’re trying to keep connected change, regardless of those connections? Where will species be in fifty years and another 2°C? Which species will remain if the current estimate of a million extinctions worldwide in this century proves true? This is not just about the migratory mule deer and pronghorn antelope, but the plants they rely on. Not just the perambulatory mountain lions, but their prey too. Not just moose, but their marshes.
It’s essential that we remember, in this discussion about wildlife corridors, that climate and biodiversity are inextricably linked. A crisis in one is a crisis in the other, and the worsening crises in both are synergistic. That is, they each accelerate the other. Ecosystems are made of carbon (among other things), and a healthy, flourishing planetary landscape in a stable climate pulls in and stores about the same amount of carbon it emits. A fragmented, diminished, dry and fire-prone landscape emits more carbon than it absorbs. (Already parts of the lush Amazon have become, as they dry, net CO2 emitters.) Some wisdom on all this may be found in the latest essential book from Paul Hawken and company, Regeneration: Ending the Climate Crisis in One Generation:
Terrestrial and coastal ecosystems contain more than three billion tons of carbon, nearly four times the amount of carbon contained in the atmosphere. Three decisive actions are required to stop global warming. First, reduce and eliminate emissions from fossil fuel combustion. Second, sequester carbon into the soil by photosynthesis in grasslands, forests, farmlands, mangroves, and wetlands. Third, protect the carbon here on earth… A 15 percent loss of terrestrial carbon could result in a one-hundred-parts-per-million increase in atmospheric carbon dioxide. Establishing wildlife corridors is crucial to preventing that loss.
Why are wildlife corridors crucial? Because the effort to reconnect habitats is an effort to let life thrive, and because the creation of corridors implies a companion effort to protect the habitats that are being connected. Natural stability is the goal. The more species (plants and animals) can live out their lives as they have for millions of years, the more likely the Earth will still be stable and familiar to all of us in a hundred years. The “terrestrial carbon” described above is life itself. Protect life in its marvelous diversity and you keep carbon on and in the ground.
Of course we, in our fossil-fuel-driven imitation of a supervolcano, have changed the planet considerably already and are primed to keep doing it for a while. Which leads to one more reason that wildlife corridors are important in the climate crisis: Because creating and protecting linked landscapes provides room to move for species as they adapt to new weather regimes and altered ecosystems. How much change is coming, how many species can/will adapt, and how much adaptation they will make, is up in the air.
We will see. For now, to mend the carpet and help the civilizational transition to a safer and more humane network of roads, we can advocate in our states to begin or expand efforts to build wildlife crossings. I highly recommend perusing the ARC and CLLC websites for a quick education on road ecology, corridors, and crossings.
The first, best steps for states which haven’t begun the process would be first to replicate the good work being done elsewhere, like the coordination between transportation and fish/wildlife departments in western states and like the Stream Smart program here in Maine. It also makes sense to empower citizens to document sightings of roadkill and wildlife on the roads so that highway departments can justify the expense of building crossings. There’s power in data. Unfortunately, while both the Road Ecology Center at UC Davis and the Center for Large Landscape Conservation have designed apps for this, neither seems to be widely available. You can learn more about the CLLC app, ROaDS (Roadkill Observation and Data System) here, and the REC app here.
Another good way to help is to support, either financially or by volunteering, your local land trusts, especially on projects that are meant to connect habitat. Here in my part of Maine Coastal Rivers Conservation Trust and Midcoast Conservancy are doing great work.
Finally, I was motivated to write on wildlife crossings because of this excellent New York Times article, which comes complete with a plethora of happy videos of animals using the crossings. Enjoy.
Drive safe, everyone, and if you see a caution sign about wildlife crossing ahead – especially moose – pay attention.
Every stretch of road is a possible intersection with an animal on its own path.
