Ivory-billed woodpecker

The Search for the Holy...“Grail Bird”?

By Ashley Lohr, Alexa Turner, Auri Stephenson, and Andrew Greenberg


For as long as humans have walked on this earth, birds have soared through the skies and waded through water. Many of these species are magnificent in their own way, whether it is due to exceptional plumage dimorphism or a unique feeding strategy. However, a large majority of these species are now on the decline as a result of deforestation, human development, and poor hunting regulations. The mysterious ivory-billed woodpecker (Campephilus principalis) is unfortunately one of the many species caught in the middle of these human-induced quandaries.

Numerous mis-sightings have occurred
due to striking resemblances between these birds.
From left to right: imperial woodpecker,
ivory-billed woodpecker, and pileated woodpecker.
The ivory-billed woodpecker has been considered extinct for nearly 60 years. However, as the title of this post implies, birdwatchers never gave up hope that this magnificent bird had somehow survived. That is how the ivory-billed woodpecker earned its nickname, the “Grail Bird,” an allusion to the Holy Grail.   Many people claim that they have made a reappearance, yet they remain on the critically endangered and possibly extinct IUCN Red List. This bird requires a lot of personal space for mating and reproducing so they were greatly affected by deforestation. Historically, each pair required about 25 square kilometers for survival, mostly situated in the south and ranging from east Texas to North Carolina and from southern Illinois to Florida and Cuba. Ivory-billed woodpeckers require mature old-growth forests with access to water because they excavate cavities for shelter in mature trees and drill into dead trees when searching for wood-boring beetle larvae, their main source of food. Their habitats were severely depleted, leading to intense competition for what little space was left. Also, these woodpeckers are large, beautiful birds, so they made excellent trophies for hunters. Between deforestation, hunting, and low reproductive rates due to small clutch sizes (the number of eggs laid), this species could not recover and eventually fell into extinction. Fortunately, there is much interest in these birds; bird enthusiasts and endangered species activists alike would love to see this bird restored in our lifetime.

Reintroducing critically endangered or even extinct species is tedious and tricky. Often, “surrogate species” are used to supplement and nourish a cloned individual as it grows from an embryo into a viable offspring. Although extremely complex, the method most often used for cloning is
somatic cell nuclear transfer. (The linked site provides a thorough but comprehensible breakdown of this process.) In this case, the ivory-billed woodpecker’s closest living relative would be the imperial woodpecker (Campephilus imperialis). Both of these species are members of the genus Campephilus, a group of large American woodpeckers. The only problem is that populations of this potential surrogate species are also extremely low in numbers; some even call this bird extinct. Perhaps by focusing our efforts on a resurgence of the ivory-billed, we can also bring back the imperial woodpecker. Imperial woodpeckers also prefer a southern climate, but they are more specific in their tree species. They have a preference for loblolly pine (Pinus taeda) and Montezuma pine (Pinus montezumae), as well as Mexican white oak (Quercus polymorpha) and other oak trees in Mexico. They too lay a small clutch size so it would be hard to stimulate population resurgences. The best plan would be to begin with an imperial woodpecker captive breeding program followed by introducing ivory-billed DNA to begin restoring our focal species. This means that two species could be saved at once considering the same solutions would help them survive in greater numbers.

One benefit, but also a potential problem, of reviving the ivory-billed woodpecker is human interest. There is already a large online following, and when there were rumors that they may not be extinct, enthusiasts and experts
flocked to the site. This is strong evidence that if we were to actively reintroduce the species, there would be a large following. This creates economic benefits because people scurrying to see them would ultimately bring in revenue for gift shops, restaurants, and hotels, therefore stimulating the economy of the area. However, this would also disturb an already shaky species. By allowing people to visit the area of interest, they are disrupting the habitat that the species is trying to settle into. People may also reintroduce bacteria or infectious diseases that existed sixty or seventy years ago but have evolved significantly since that time period, running the risk of exposing these birds to potentially more resistant strains of diseases. This could trigger an epidemic within the species, especially since there isn’t much documentation on diseases that are associated with this bird. Lastly, this copious amount of activity could stress the birds, which would suppress their immune systems and redirect efforts for survival, perhaps even killing the individuals in the process. If introduced to a national park, there are regulations on the densities of people allowed in the park, as well as what they are allowed to do. This would hopefully reduce the stress on the animal.

Another issue to combat is the habitat. Ivory-billed woodpeckers, as stated before, require a lot of space per breeding pair, around 25 square kilometers (~6,800 acres). They also require a warmer climate and trees with various stages of decay for food, shelter, and reproduction. The best place for them to live would be in a national park somewhere in the southern United States, as the last place they were seen was Louisiana or Mexico. One good option as a mid-point between the more mid-range tolerance of the ivory-billed woodpecker and the strict warm climate for the imperial woodpecker would be the Angelina National Forest in east Texas. So much of their habitat has been destroyed by human development that they do not stand a chance in a non-protected environment. The biggest problem with placing them in a park is the fact that forest managers will clear the dead and decaying trees to prevent insect-related diseases from spreading throughout the forest. Depletion of the dead and decaying trees would remove the birds’ food source, and clearing out partially decayed trees would eliminate their nests. There would have to be a policy to leave these trees in certain areas specifically for the ivory-billed woodpeckers.  The national parks would protect against deforestation and encroaching human development, but the habitat could still be impacted if these appropriate policies are not implemented.


Ivory-billed woodpeckers require mature trees
for excavating cavities for their eggs and large, 
 dead trees that house their main food
source: wood-boring beetle larvae.
As you can see, a reintroduction program is not going to be easy; it will have its challenges, whether they be compromising with national park services or insect pest management programs, or successfully stimulating a surrogate mother to nourish an embryo and lay an egg. However, no matter how difficult the path may be, many conservationists, environmentalists, and nature-lovers in general would say it is our responsibility to restore this species since human activity brought their numbers down in the first place. Maybe one day we’ll once again see gorgeous, giant woodpeckers with prominent crests on their heads flying around old-growth forests they can rightfully call their own.

Further Reading:

Article 1:
Ivory-Billed Woodpecker Persists in Continental North America

Article 2: Uncertain sightings and the Extinction of the Ivory-Billed Woodpecker 

Article 3:
Specimen-Based Modeling, Stopping Rules, and the Extinction of the Ivory-Billed Woodpecker

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The Lord God Bird: how a "definitely or probably extinct” species may make a comeback

By Kat Bryan, Kerry Jefferies, Kelsey Schoenemann, Katie Schroeder

The ivory-billed woodpecker (Campephilus principalis) is known colloquially as the “Lord God Bird,” based on exclamations made by surprised onlookers. It was one of the largest woodpeckers in the world. It was last seen in Arkansas in early the 2000s and presumed extinct. Carl Linnaeus classified the ivory-billed woodpecker in 1758.

It can be distinguished by being a shiny blue-black with white markings on its back. The crest is black on females and a bright red on males. As its name implies, it has a distinct, ivory-colored bill. Their range extended from Texas to North Carolina and from Illinois to Florida. It lives in a temperate climate, in thick hardwood swamps, pine forests with dead or decaying trees. It feeds on larvae of wood-boring beetles, seeds, fruit, and insects.

The ivory-billed woodpecker is an iconic species. This elusive bird has inspired a festival in Brinkley, Arkansas (including exhibits, birding tours, educational presentations, and a vendor market) and a “Sufjan Stevens song” called “The Lord God Bird.” Indeed, speculation about the bird’s return has significantly increased tourism to areas where it once occurred, like Arkansas, Florida, and Georgia.


Extinction: 
Even when healthy populations existed, this species occurred at low densities (with each pair of ivory-bills requiring a least 6 square miles of territory). As such, it had always been a rare bird. Habitat destruction began following the Civil War, when timber industries began to harvest large quantities of timber from the birds’ home range. This deforestation continued through the 1940s, and only stopped when there was no more lumber to collect. By this time, suitable habitat was sparse and this led to a devastating drop in the population.

Further exacerbating this population decline were scientists and prize hunters who took to hunting the bird once it became rare, either to add it to a scientific collection or to earn personal glory. This ultimately led the precious bird to extinction. However, with one of the newest scientific discoveries of “de-extinction” this culturally important bird has the opportunity to make a reappearance.

Obstacles:

Successful re-introduction of the ivory-billed woodpecker can be secured only if the original causes of the bird’s extinction are remedied first. For instance, habitat destruction, one of the primary causes of this species’ downfall, must be reversed. Thick hardwood swamps and pine forests with dead and decaying trees must be restored. These areas had heretofore been ravaged by logging operations. Wherever one hopes to reintroduce this species, logging must be prohibited.

The next issue is predation. Ivory-bills have many predators, such as weasels, rat snakes, gray foxes, red-tailed hawks, and great horned owls. Furthermore, there could be other competitive species that disrupt the new (and vulnerable) population, extirpating them once more. The final issue to address is humans disturbance. People could cause further harm to a growing population through habitat destruction or overexploitation, as has happened in the past with this species.



Management:

We recommend releasing a few individuals at a time into restored, protected habitat, in which hunting is disallowed. Because the species is generally monogamous, males and females should be released in equal numbers. Obstacles to successful establishment include habitat availability, predation, and human disturbances or illegal takes. To combat these, we recommend the creation of “
green corridors” between patches of habitat, limiting logging operations surrounding protected areas, and restricting public access to reserves. Our target population size is about 25,000 individuals, which will put the species well above the threshold for being considered threatened or endangered. We suggest tracking many of the initial releases by attaching radio-tracking bands to their feet.

Given that the species extinction was largely due to human activities (rather than natural causes), stakeholders like loggers, farmers, hunters, recreational users, and developers, will be expected to make significant compromises to insure the species survival. Critical to the success of this plan is public cooperation, which might be secured by impressing upon them the cultural and ecological importance of this species.

Further Reading and References:

Boyle, Gerry. (2005). "Searching for the Ivory Bill." Colby. Colby College. Web.

Jackson, Jerome (2002). "Ivory-billed Woodpecker". Birds of North America Online.

"Ecology and Behavior". The Cornell Lab of Ornithology.

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