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A Chilly Day at Alligator River


November 14, 2017. I’ve spent a few days in November at the Outer Banks of North Carolina every year since 2010 now, and every time I go I learn something new. In past years I’ve written stories about the ponds and forests of the Nature Conservancy’s Nags Head Woods Preserve, the biogeographical boundary between northern and southern species found on Roanoke Island, and the ecological patterns at Cape Hatteras that are the result of climate changes and sea-level rise and fall before and since the last great Ice Age. There are such rich ecological stories here, from biogeography to fire ecology to endangered species conservation, that I can barely scratch the surface in one essay. This past November my ecological explorations focused on the Alligator River National Wildlife Refuge, located on the North Carolina mainland southwest of Roanoke Island, just inland from the Outer Banks.

Alligator River is, of course, named for the American alligator, Alligator mississippiensis. Look at the map of the range of the American alligator, and you’ll see that the Alligator River NWR is the northeastern tip of its sprawling range along the southeastern and Gulf coasts of the U.S.; the mouth of the Rio Grande River in Texas is the southwestern tip. The well-informed and very talkative senior-citizen volunteer at the Coastal North Carolina National Wildlife Refuges Gateway Visitor Center near Manteo told us that an alligator had been seen recently hanging around in a canal at the end of the Creef Cut Wildlife Trail in the reserve, so we headed there to try to see the world’s northeasternmost ‘gator. But it was a chilly, overcast day – not ideal for reptiles, whose body temperatures vary and more or less match that of their environment, a condition called “poikilothermy” by biologists. Alligators love basking in the sun on warm wet banks, but today there was no sun, and the November water was certainly unfriendly for poikilotherms. The alleged alligator was apparently huddling elsewhere.

Because of anthropogenic climate change, alligators may be looking north. Trump promised to “drain the swamp,” but so far he has only deepened and enlarged it. Alligators are undoubtedly grateful that Trump pulled the U.S. out of the Paris Climate Accord. They will be swimming in the Tidal Basin in front of the Jefferson Memorial even sooner than if he hadn’t, waiting to snack on an unsuspecting viewer of the famous Japanese flowering cherry trees. It probably won’t happen in my lifetime, but I wonder how the National Park Service will react to that brazen act of ecological revenge. Beavers, a circumpolar northern species, have already made an ecological attack there, cutting down a few of the prized trees, to the consternation of the Park Service, which promptly trapped and removed them.

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The Alligator River NWR, established in 1984, protects 153,000 acres of forested wetlands and the wildlife species that inhabit them. The most unique ecological community of the refuge is called “pocosin,” a native American word meaning “swamp on a hill.” In this area, falling sea levels caused by climate changes since the last Ice Age have created what hydrologists call “perched water tables” and ecologists call “raised bogs.” Pocosins are forested wetlands with deep, acidic, nutrient-deficient peat soils that have resulted from an accumulation of undecayed organic material over millennia. They are like giant sponges, holding vast quantities of water. However, during droughts that occur every ten years or so in this area, pocosins dry out and are very susceptible to wildfires. About a third of the Alligator River NWR is covered by pocosin dominated by pond pine, Pinus serotina. Pond pine is a fire-adapted and fire-dependent species, whose cones remain closed and attached to the branches until a fire burns through and opens them with heat, releasing seeds to recolonize and dominate the habitat. The scientific species name of this pine, “serotina” refers to this adaptation to fire. Fires sometimes burn deep into the peat soil, creating small ponds – thus the seeming incongruity between the scientific and common names of this pine species. Pocosin ecosystems once covered about 2.5 million acres in eastern North Carolina. Extensive drainage for agriculture, forestry, and peat mining have dramatically reduced them, and now Alligator River protects a significant fraction of what remains.

Pocosin wetland, Sandy Ridge Wildlife Trail, Alligator River NWR. November 2017.

Pocosin wetland, Sandy Ridge Wildlife Trail, Alligator River NWR. November 2017.

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Alligator River NWR is ground zero for a textbook example of the struggle to bridge the gap between science and public policy, and to make policy “science-based.” At the NWR’s Visitor Center in Manteo I talked to Joe Madison, the project leader of the Red Wolf Recovery Program for the U.S. Fish and Wildlife Service (USFWS). Joe has a big challenge.

Red wolf, Canis rufus

Red wolf, Canis rufus

Before European settlement the red wolf ranged across southeastern North America from eastern Texas, around the Gulf and Atlantic coasts, and north to approximately southern New York. Humans exterminated these predators from most of their range and brought them to the brink of extinction. They were one of the first species listed under the Endangered Species Act when it was passed in 1973. According to Defenders of Wildlife, a non-profit conservation organization, the red wolf has been eliminated from more than 99 percent of its historical range – more than any other large carnivore anywhere on Earth, including tigers and snow leopards.

In a pioneering and desperate attempt to implement the Endangered Species Act and save the red wolf, the USFWS captured what it decided were the last surviving wild red wolves from the salt marshes along the Gulf Coast of Louisiana and Texas between 1974 and 1980, and transported them to the Point Defiance Zoo in Tacoma, Washington. A captive breeding program there was supposed to increase their population to a level suitable for reintroduction. In 1980 red wolves were declared extinct in the wild so that the USFWS could legally proceed with restoration efforts. It was the first captive-breeding rescue program under the Endangered Species Act, and it became a model for later programs to restore the whooping crane and California condor.

Finally, in 1987, four pairs of captive-reared red wolves were reintroduced into the Alligator River NWS, which had only been established three years earlier. Over the next 20 years the population grew to around 120 individuals, and packs spread beyond the refuge onto private land in surrounding counties on the Albemarle Peninsula. But in the last decade they have encountered resistance, both social and ecological, and the population has declined dramatically. Red wolves are hit by cars, shot by local residents, and interbreed with coyotes that have expanded into their range. Joe Madison told us he estimated that only 35 to 40 wild red wolves still roam the five counties around the Alligator River NWR. Once again, the red wolf is on the brink of extinction in the wild.

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The first American naturalist to describe this wolf species was William Bartram of Philadelphia, about whom I’ve written before. Bartram travelled south through the Carolinas and Georgia to Florida just before the Revolutionary War, and published his notes and stories in 1791 in a book with the short title “Bartram’s Travels.” He described these southeastern wolves as having a variety of coat colors, from black to reddish. Another famous American naturalist, John James Audubon, depicted what he called the “Red Texas Wolf” in The Quadrupeds of North America, the mammalian counterpart to his famous portraits of birds, published in 1849.

Red Texas Wolf. John James Audubon. 1849.

Red Texas Wolf. John James Audubon. 1849.

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The genetics of red wolves “are a mess,” according to Joe Madison. For me, trained as an evolutionary ecologist and behavioral geneticist, another and more scientific and positive way to put it is that red wolves are a fascinating and still unsolved evolutionary puzzle. One of the most interesting questions concerns the evolution of the social behavior of the species, semispecies, and subspecies of the canid (dog) family. Why, for example, do red wolves seem to form social bonds and groups that are intermediate between those of gray wolves and coyotes?

I think Joe’s use of the word “mess” in this case, given his role as recovery coordinator, actually stems from how the not-quite-resolved genetic and taxonomic status of the red wolf complicates their conservation under the Endangered Species Act. Amendments in 1978 recognized what were called “distinct population segments,” which allow vertebrate species to be divided into distinct subpopulations based on geography and genetic differences. Those geographically-separated and genetically-differentiated subpopulations are precisely the “stuff” that evolution needs and works with.

Here’s a quick summary of what Joe Madison called a “mess.” A genetic study in 2011 indicated that the red wolf has a mixture of genes that suggest it may be a hybrid of gray wolves and coyotes. But a 2012 scientific paper, “Conservation genomics in perspective: A holistic approach to understanding Canis evolution in North America,” reanalyzed this study and concluded that the red wolf is a separate species that it has experienced a significant introgression of coyote genes because of “decimation of red wolf packs and fragmentation of their social structure due to hunting.” Another 2012 study by the U.S. Fish and Wildlife Service concluded that “the red wolf is a distinct species which diverged from the coyote alongside the closely related eastern wolf 150,000–300,000 years ago.” Although this 2012 review by the USFWS was not universally accepted, two subsequent reviews of updated research published in 2013 and 2014 suggest that the red wolf was once a species distinct from the gray wolf and coyote. A 2016 scientific paper proposes that North American gray wolves and coyotes are more closely related than previously thought and may have split into two species relatively recently. The red wolf may represent a remixing of these species; the authors of that study argued against a “black-and-white species concept,” and recommended that red wolves be protected. Indeed, evolution works in shades of grey, not black and white, and the Endangered Species Act should try to protect the complexity and evolutionary potential of any species complex, however muddled at this point in time.

And here is the latest I can find on how the U.S. Fish and Wildlife Service is dealing with the conservation of the endangered red wolf: a USFWS press release from September 2016 says that “Recovery of the red wolf in the wild is feasible with significant changes that must be implemented to secure the captive and wild populations,” and that USFWS “will begin implementing a series of actions based on the best and latest scientific information.” The press release said that “the Service will move quickly to secure the captive population of red wolves, which we now know is not sustainable in its current configuration; determine where potential new sites exist for additional experimental wild populations by October 2017; propose to revise the existing experimental population rule to apply only to the Dare County Bombing Range and Alligator River National Wildlife Refuge, where stable packs exist on federal lands… by December 2017; and complete a comprehensive Species Status Assessment and five-year status review for the red wolf… This will guide the Service’s recovery planning in the future.” I searched online for that promised assessment or any other updated information on red wolf recovery, and can’t find anything now in late December 2017. I assume that the USFWS has been delayed in completing it for some reason.

According to Defenders of Wildlife, “There is absolutely a path forward for red wolf recovery in the Southeast. The science is there but it requires commitment from the U.S. Fish and Wildlife Service. Instead of pulling red wolves from the wild, the agency needs to step up and increase their efforts to recover this incredibly rare species. That means releasing captive red wolves into the wild again, working with landowners to implement coexistence strategies, and investigating additional sites for reintroduction.”

Whew! It’s complicated! When evolutionary biologists are still trying to sort out the mysteries of the evolution of wild canids, how can policy-makers – the USFWS in this case – support that ongoing scientific research by protecting the wild populations of these evolving species? This complexity seems to me all the more reason to save wild red wolves as a case study in how evolution works.

Although I was in the Alligator River NWR, the last remaining holdout of wild red wolves, I only heard their howls for help through human voices: those of the USFWS recovery coordinator, the scientists struggling to ascertain their evolutionary status, and activists advocating for their conservation in the wild. But taken together those were a clear chorus, calling for action.

 

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Red wolves are not the only endangered species listed under the Endangered Species Act that call Alligator River home. In a previous visit to the reserve in 2010, I’d seen a red-cockaded woodpecker in the pocosin ecosystem along the Sandy Ridge Wildlife Trail. The red-cockaded woodpecker, Picoides borealis, was one of the first birds protected under the Endangered Species Act. As we walked that trail again on this chilly afternoon I was on alert, but didn’t see or hear a woodpecker of any species.

Red-cockaded woodpecker, Picoides borealis

Red-cockaded woodpecker, Picoides borealis

But all along the boardwalk trail were young Atlantic white cedar! I’m very partial and deeply grateful to this now-rare tree species, and always on the lookout for it, because I own a beautiful lightweight canoe made from thin strips of its unique wood. I’ve paddled that canoe on many memorable adventures, and so my gratefulness. Atlantic white cedar has excellent properties for boat building and it was in especially high demand during the peak era of American whaling in the middle of the 1800s – it was the favored wood for the whaleboats that chased and harpooned whales from the sailing vessels where the catch was processed and rendered for oil. Atlantic white cedar is adapted to reproduce after major disturbances like hurricanes or fires that destroy an existing forest stand and expose bare soil. Because of its association with ecological disturbances like fire, it often mixes with pond pine, its fire-adapted companion.

My Atlantic white cedar canoe at Mispillion River, Delaware, with spawning horseshoe crabs

My Atlantic white cedar canoe at Mispillion River, Delaware, with spawning horseshoe crabs

A significant portion of the Sandy Ridge trail is boardwalk that passes above the pocosin swamp. Anytime I’m on a boardwalk, with my feet isolated from the actual ground of the ecosystem, I can’t help but think of Ray Bradbury’s classic short story, “A Sound of Thunder.” This story, for me, is an exemplary tale of the interface of chaos theory, evolution, and ecology, and a warning of why the “precautionary principle” is especially demanded while we humans tinker unintelligently at this interface, as I’ve written about before in blog essays titled: “Chaos in Colorado,” and “Delta Blues.” My November trip to Alligator River illustrated and reinforced this message.

Boardwalk on the Sandy Ridge Wildlife Trail, Alligator River NWR. November 2017.

Boardwalk on the Sandy Ridge Wildlife Trail, Alligator River NWR. November 2017.

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The same friendly volunteer in the NWR’s Visitor Center who sent us on the unsuccessful alligator chase on the Creef Cut Trail suggested that the place to see red-cockaded woodpeckers was at the Palmetto-Peartree Preserve in Tyrell County, NC, near Columbia. On my I-phone, Google Maps showed it to be about 45 minutes from where we were in the Alligator River NWR, so in the middle of the afternoon we decided to go for it. As we drove westward we got a glimpse of the scattered rural life of Tyrell County, one of the five North Carolina counties where red wolves still roam and howl in the wild, and are still killed by cars on the roads, and shot by some of the locals who oppose their comeback here. As we approached our Google-maps goal, the directions got a little complicated. We ended up on a dead-end sand road at a windy beach facing the whitecaps of Albemarle Sound. Where were we?

The Palmetto-Peartree Preserve, according to Google Maps. November 2017.

The Palmetto-Peartree Preserve, according to Google Maps. November 2017.

This didn’t look like old-growth pine habitat favored by the red-cockaded woodpecker, but like a coast being drowned by sea-level rise. We backtracked, rewound, and re-read the driving directions, and finally found a small, faded sign for the Palmetto-Peartree Preserve. With the mid-November sun sinking fast, and a long drive back to our base on the Outer Banks, we realized the chances of seeing red-cockaded woodpeckers this afternoon were… well, zero. We gave up and headed east in the fading daylight. It was the woodpecker equivalent of a “wild goose chase,” but at least we could say we’d given it our best effort.

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About Bruce Byers

Bruce Byers Bruce Byers Consulting provides technical assistance to government agencies, NGOs, and the private sector in the U.S. and over­seas. We carry out assessments, analyses, and applied research that provide the background information needed to design effective strategies and actions in complex ecological and social contexts.

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