Learning from the ivorybill


Drawing by Mark Bowers, from the U.S. Fish and Wildlife Service website
(link via The Daily Blatt)

1. Mr. Wile E.

A week ago, when I heard the news about the rediscovery of the ivory-billed woodpecker, I was – as I mentioned – afflicted with a sudden and unaccustomed surge of joy and hopefulness about the state of the planet. After a couple hours of reading on-line articles and corresponding with my two birder-brothers about it (my parents being on vacation and out of e-mail reach), it occurred to me to send a message to the listserve of the Pennsylvania Biodiversity Partnership in my capacity as co-chair of the Public Lands Committee of the Pennsylvania Chapter of Sierra Club. After a link to the Cornell Lab and a few other remarks, I concluded, “The message for Pennsylvania is clear: Recover It (old-growth forest) And They Will Return.”

Yes, that’s right. Even in the midst of my jubilation, I couldn’t resist putting my own spin on things. And in fact, it bore satisfactory results: it sparked a good discussion of old-growth on the listserve, and my reaction against my own opportunism led to a half-decent poem two days later.

But Coyote wasn’t fooled. I neglected to mention this at the time, in part because I figured y’all might suspect me of making it up. But it’s true. It was about nine o’clock that evening, and I had been listening to some of my favorite country blues cassettes (remember cassette tapes?) while drinking three or four celebratory bottles of homebrew. (It was, unfortunately, too cold to sit outside.) Then I got hungry, and remembered some leftovers up at the other house, in my parents’ refrigerator. The night was dark. Just as I got to the top of the hill, a coyote let loose from the middle of the field – less than a hundred yards away. The hair stood straight up on the back of my neck. He or she howled a couple of times, then barked like a dog: Har! Har! Har! Har! Har! I scuttled inside, grabbed the highest-powered flashlight I could find, and shone it back and forth across the field, hoping to pick up the eye shine, but the animal had already slipped away.

Now, to appreciate this incident, especially if you’re from out west, you have to understand a couple of things. First, that eastern coyotes don’t vocalize nearly as often as their western counterparts. Second: the eastern coyote is, depending on which biologists you believe, either a brand-new animal here in the east, or a once-eradicated species that reintroduced itself in the latter half of the 20th century. The latter theory postulates that European settlers, being unfamiliar with the North American coyote, simply mis-identified it as the “brush wolf” – which they then proceeded to wipe out as quickly as they could. The problem with that theory is that coyotes are virtually impossible to eradicate. Since they have always played second fiddle to wolves, it makes sense that they would evolve an extremely flexible population ecology: the more you persecute them, the faster they reproduce. Gray wolves, having evolved (at least since the demise of the dire wolf) as top dogs, have no such resilience.

But canids speciate as much by culture as by genetics, which is to say that species boundaries are readily crossed, and only mutual hostility and fear of being eaten prevent interbreeding – 99 percent of the time. A DNA analysis of eastern coyotes did strongly suggest that interbreeding with timber wolves – the smaller subspecies of wolves inhabiting eastern Canada – had occurred in the recent past. But who knows? Perhaps there were a number of regional subspecies in 1600. Some biologists argue that the Pennsylvania “brush wolf” was neither gray nor timber wolf, but the red wolf of the southern Appalachians.

Does Coyote care about all this? I think not. This new/old wild canid has figured out that frequent howling in the densely populated east is not advantageous. Nearly every hunter in this state owns a powerful spotlight, and coyotes may be shot anytime as a varmit. The easiest way to do this, I’m told, is by playing tapes of their howls. Meanwhile – and very anecdotally – I hear from folks in Vermont and West Virginia that an even larger coyote is beginning to appear. It’s probably only a matter of time before wild canids in the northeast switch from opportunistic predation to direct reliance on our hugely over-abundant white-tailed deer herd. I hope.

Of more direct relevance to the ivorybill rediscovery is the fact that the presence of coyotes in the state was officially denied for years – decades, in fact. Even as sightings grew more frequent and the evidence more and more overwhelming, spokespeople for our state wildlife agency continued to deny the obvious. The name of this agency might tell you why: it’s the Pennsylvania Game Commission. It derives almost all its funding from the sale of hunting licenses, and all license increases must be approved by the state legislature. Game Commission folks knew that the interval between official acknowledgement of the coyote’s presence and demands for its eradication would be about two or three nanoseconds, so they stalled as long as they could. When it finally became impossible to deny the obvious – some fifteen years ago now – they announced it as a wonderful new addition to the state’s already impressive roster of legally trapable and shootable critters. They made it sound like such a good thing, in fact, that to this day they are regularly accused by more credulous members of the hunting fraternity of having deliberately introduced the animal, as part of vast and sinister conspiracy between anti-hunters, the Audubon Society, and the United Nations. These are, of course, the same anti-hunters who want to slaughter all the deer in the state. As Dave Berry would say, I swear I’m not making this up.

In fact, I know this guy who knows a guy who drives truck, and one time about fifteen years ago, after a couple beers, he says to my buddy, “You won’t believe what I got in the back of my truck…”

2. How much old-growth is enough?

One of the first two responses to my e-mail to the Biodiversity Partnership listserve raised some interesting questions:

I have been told the ivory-billed woodpecker has been seen by outdoorsmen in the Arkansas area for years. No one of any “authority” believed the people who saw them. Now that some upper-shelf person saw one, it is now for real. Great, but the same can be said for other animals in the eastern US: cougars, badgers, wolves, lynx, Allegheny wood rat etc. come to mind. It is time we get our heads out of the sand and put a little effort into documenting other animals in our midst.

The author, Gene Odato – chief of the Rural and Community Forestry section of the Pennnsylvania Bureau of Forestry – responded to my spin with some of his own. If some of these supposedly endangered or regionally extinct species are, in fact, present, then what do we have to worry about? If anything, we have too much old-growth – and not enough young forests.

I would like to know more about the nature of that forest in the Cache and White River bottoms: year last cut, degree/type of management, etc. That would be very instructive to us all.

I would also like to know more of the management details of the land the woodpecker inhabits. As for PA or any other state: How much old-growth is enough without damaging the lives of the people who depend on the wise use of the forest? The public land such as the national forest and in particular the state forest of PA already manage 30% to 50% of the forest as old-growth. How much more do we need without sacrificing the habitat needs of hundreds of wildlife and plant species that depend on early successional forest, poletimber-sized forest?

I asked my brother Mark to do some digging – something which, as a geographer, birder and conservationist, he didn’t have to be asked about twice. In fact, even before he headed over to Arkansas last Saturday, he fired off a preliminary e-mail in response to some of Gene’s concerns.

All I can say at this point is that Arkansas appears to be quite a bit more advanced than Pennsylvania – after all, its motto is “The Natural State” rather than the “Keystone State.” Arkansas parks are some of the most impressive I’ve seen. It takes some guts or gall to block a bridge across the Mississippi River from this county (Bolivar), the epicenter of cotton production in the US, across to Ark, but they did it years ago to avoid destroying the White River Refuge. Thanks to the White River National Wildlife Refuge, there is no unbroken road along the Mississippi River on the west side of the river through Arkansas. (Where this bird was rediscovered, however, is right off the Interstate, well north.)

I’m just not quite convinced that people up in the northeast can conceive of the size of some of the wildernesses down here, nor understand that the old-growth was logged as recently as the 1940s, and never really completely, at least in Arkansas and Louisiana (Mississippi is a different, sadder story, of course) – the Big Forest, like this side of the river, was mostly wilderness until the end of the 1800s, so analogous to the Big Thicket [in Texas]. There are still several million acres of flooded bottomland hardwood forest in the lower Mississippi River Valley, and probably the single highest biodiversity indices, as well as biomass production. The Mississippian civilizations arose here; Poverty Point mound civilization, living with and off the untold millions of waterfowl and fish and etc. and so forth.

The point is that the region has been all but forgotten by most conservationists – sort of like living in Brazil and forgetting the Pantanal or whatever. The Mississippi, White, Cache, Pearl and other rivers are still free-flowing and undammed. There are still virgin canebrakes (bamboo forests) on private land. I’m already getting a bit impatient at urbanites who pay attention to areas only when Audubon or the Conservancy make them into big destinations. I wrote about listening to local voices in my book on Honduras. Almost no one does that here.

3. Accomodating a “magnificent misanthrope”

The White River flows south, joining the Arkansas just above its junction with the Mississippi in the middle of a huge roadless area comprising some 125,000 acres, much of it still in private hands. The White River National Wildlife Refuge (NWR) stretches north along the river from there, joining with the Cache River and its attendant NWR just south and for many miles north of Interstate 40. It was to the latter location that Mark and family headed last Saturday after motoring up the fabled Highway 61, unable to simply cross the river at Rosedale due to the State of Arkansas’ atavistic dislike for Progress.

As his e-mail indicated, the verified ivorybill sightings reported in Science were all along the Cache River, within a very short distance of the interstate. The U.S. Fish and Wildlife Service folks at the Cache River NWR were very forthcoming and were able to answer all his questions, he said: he and his family were virtually the only visitors to arrive there all day. The wildlife refuge had designated special observation points beyond which it intends to restrict access – 5,000 of the refuge’s 60,000 acres have been closed. All the high officialdom were there, braced for an onslaught of crazed birders that never happened. It seems the word had gone out over birders’ listserves to stay home and leave the ivory-billed woodpecker in peace.

The only problem, Mark said, is that no one really knows what disturbs an ivory-billed woodpecker. Various theories are circulating about why the bird has proved so darned elusive for the last half-century. Perhaps, as my brother Steve suggested last week, it has learned and inculcated in its young an extreme wariness toward human beings – “a magnificent misanthrope,” he called it. Mark replied that this seemed plausible – at least based on his experience with some rare birds and mammals in Central America – but added that the White River area, which is now presumed to harbor a breeding population of ivorybills, is formidably remote and difficult of access. Ivory-billed woodpeckers don’t migrate, and the literature says that their breeding territories can be quite small for a bird of that size – no more than a couple square kilometers.

So presumably the male sighted up near I-40 is a dispersing juvenile looking for new territory. What makes this area attractive? It harbors the oldest known stand of bald cypresses in the United States, Mark said – trees over two thousand years old.

Mark went on to say that – contrary to the essay by John Fitzpatrick that I quoted here last week – the forests down there were never completely cut-over. According to the Cache River NWR managers, many patches of older forest remain, though none of them may be “virgin” – the oaks, pines and other valuable trees were, indeed, all taken at some point, but many stands of bald cypress and black gum were not. Thus, the ivorybill probably never ran out suitable nesting trees.

The limiting factor, then, back during the most severe bottleneck period following the end of the timber boom, would have been food. As a woodpecker, the ivorybill has a very high-protein diet (though it does eat lots of fruit, too). According to stomach-content analyses performed in the early 20th century, most of its protein was derived from one family of insects – longhorn beetles. The larvae of these beetles live in the wood of standing dead trees, including oaks and pines – the species that were high-graded out of the swamps some eighty years ago. There must have been some awfully lean years for an awfully small and secretive remnant population of ivory-billed woodpeckers.

Now these trees are recovering – and even better, they’re dying and being left to rot in place rather than being “salvaged,” as would probably happen if it were a Pennsylvania state park or forest. Mark noted that floods and beavers are part of the natural disturbance regime of Mississippi floodplain forests; high waters regularly kill pines and oaks without bothering the true swamp species – cypress and black gum. The NWR managers told him that they adopt a passive management approach to reforestation. The Cache River website lists “Protect and restore the bottomland hardwood resources of the basin” as one of the four, main Refuge Objectives. Management Tools include public hunting and “Water management for waterfowl, wading and shore birds.” In Dahomey NWR on the Mississippi side, Mark said, this includes the occasional dynamiting of beaver dams.

This area of Arkansas – the Big Woods – is wild. It’s home to a healthy population of black bear, and panthers are moving in. The human population is low and dropping at about ten percent a decade, Mark said. The Fish and Wildlife Service people told him that the local reaction to news of the ivorybill’s rediscovery seemed mostly positive, and this isn’t surprising – wildlife watching, hunting and fishing already make a substantial contribution to the local economy. It’s a myth that public opinion changes more slowly in rural areas than in supposedly more progressive urban and suburban areas, Mark said.

4. Disturbing conclusions

Lessons for conservation elsewhere may be more elusive than either Gene or I were originally willing to acknowledge. The fact is, every bioregion is unique; ecologists have learned the hard way that forest succession in the east, where most canopy replacement occurs as a result of single-tree or small stand mortality, is more the exception than the rule. The so-called edaphic climax model first developed in the northeast United States still seems to be a pretty good fit for our region. But in areas of complex physical geography like the Appalachians, natural disturbance regimes may change radically over very short distances – nothing like the broad, virtually flat and geologically uniform floodplain of the Mississippi. And while we do have a few possible old-growth obligate species, present or extirpated – northern flying squirrel, pine martin, sugar maple longhorn beetle – the list is much longer for species that simply do best in mature forests, or in forests with many old-growth characteristics. Features such as standing dead timber, downed woody debris, multiple age classes – including many 150-year-plus specimens – and a healthy humus layer provide optimal habitat for many of Penn’s Woods’ most treasured species, including: winter wren, Acadian flycatcher, black-throated green warbler, blackburnian warbler, magnolia warbler, Swainson’s thrush, brown creeper, blue-headed vireo, cerulean warbler, yellow-bellied flycatcher, brook trout, goshawk, barred owl, fisher and lynx; many slow-dispersing spring ephemeral wildflowers, such as painted trillium and dwarf ginseng; most lungless salamanders, which can take over a hundred years to re-colonize a clearcut; and unknown numbers of native ferns, mosses, liverworts, lichens, fungi and invertebrates.

Actually, this situation is not atypical of forest ecosystems anywhere in the world. At least among charismatic megafauna, the number of species completely intolerant to human disturbance is very small, but the number that depend on the continuation of something very like what they evolved in is – as one would expect – very large. Many advocates for the timber industry like to point to studies that show edge and early-succession species declining, but in some cases these are species native to the Midwest whose ranges have expanded only in recent times as the land was cleared. In other cases they are species that might have been naturally rare, dependent on natural clearings resulting from the occasional stand-clearing ice storm or tornado.

Concerns about balancing the needs of humans with those of other animals are very appropriate. By why should one species monopolize 90 percent of natural resources and dominate virtually every bioregion? There’s something awfully depressing about the idea that every species and natural community on the planet persists only because human beings have decided they can tolerate its presence. This is a far, far cry from the view of Creation expressed by the Voice out of the whirlwind in the Book of Job. To pretend that we can and should manage all of nature is sheer hubris. And a narrow, species-by-species approach to conservation not only misses the larger picture, it ignores the magnitude of what we have lost in terms of sheer plant and animal biomass. The forests of pre-Columbian North America – lightly managed by human beings for millennia, mostly through fire – teemed with wildlife. Seventeenth-century explorers and settlers were nearly unanimous in their astonishment at the great numbers and diversity of fish, foul and game, even though to some it seemed forbidding, a “waste and howling wilderness.” Somewhere along the line, the Biblical vision of wilderness as a place of testing and transformation had been replaced by a fear and hatred of the untamed that haunts us to this day.

Everyone likes nice, park-like woods with great big trees and very little messy understory. Pure stands of old-growth hemlock or spruce can certainly inspire reverence, but they don’t come close to satisfying the ecological definition of old-growth, which includes trees of all ages and conditions – and much more besides. Conservationists err in putting too much emphasis on protecting stands of big trees and not enough on the need to recover old-growth forested landscapes – the natural condition for at least ninety percent of Pennsylvania and most other eastern states.

How much old-growth does wildlife need? All it can get. We need to relearn humility and begin to heed that Voice out of the whirlwind. We need to welcome natural disturbances and recognize them as blessings in disguise rather than “natural disasters” ripe for “salvage.” Many more insect outbreaks and some wildfires on public land could be allowed to run their course. Public and private land managers could do a much better job at grouping and connecting stands of “legacy trees” within timbered areas. Herpetologists tell us that uncut buffers around wetlands of all kinds should be measured in the hundreds of yards rather than in the tens or hundreds of feet, as is currently the practice (if we’re lucky). Most forested headwater areas should never be cut to protect hydrology and downstream organisms, such as our increasingly beleaguered native mussels. And all this presumes success in controlling the biggest on-going scourges of Pennsylvania forests: white-tailed deer overbrowsing, air pollution (including acid rain), and fragmentation from roads and sprawl. I don’t think any of these problems are anywhere near as severe in the Big Woods of Arkansas. But unless and until we address them, biodiversity here will continue to decline.

One way or another, it’s almost a given that Coyote – patron of unforeseen consequences – will have the last laugh.
__________

UPDATE: Mark just e-mailed me with a couple corrections (which I have made), and added the following thought:

The geography of the lower Mississippi valley alluvial swamps (bottomland hardwood forests) is similar in character to the varzea of Amazonia, though of course with the leveeing of the Mississippi River and side rivers, flooding is not nearly as extreme as it once was. However, the geomorphology is very similar, and includes huge oxbow lakes – the largest in the Americas north of Amazonia are in the Delta.

My point is that humans have lived and farmed Amazonia, and seasonally the varzea forest, for millennia, using swidden rotation (slash and burn) which involves small clearcuts. This does not mean the Amazonia (or the Peten in Guatemala, for that matter) are “second-growth”; it means that human populations are low enough that human disturbance regimes are simply another form of forest modification. Indeed, swidden, the world’s oldest form of agriculture (or horticulture), is successful in that it mimics natural treefall dynamics, widely believed to be the disturbance regime that is most important in helping create the awesomely high biodiversity of the Amazon.

When human populations swell and elite/capitalist greed enter into the equation, forests are wiped out. It is all in the temporal and spatial scale at which the destruction is taking place, however: this can quite rapid, or over decades or even centuries. Essentially, does the local human population absolutely depend on a healthy ecosystem, or not? Economics and governance are at the heart of it.

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