Field Report: 2019-03-13
Birds, Pitvipers, & Murder
The Rowley's Palm Pitviper (Bothriechis rowleyi) story
96
Hours
Hours
12
Hours of Sleep
Hours of Sleep
2/2
Target Species
Target Species
Don Tomás, as Thomas MacDougall was known in Mexico, would later write: “We were in quetzal country; here, in March, one hears much calling of quetzals. My companion Juan did not know quetzal country and was curious about the bird he had heard so much of, so, when I went toward the report of his gun, it was to find him with a fine male quetzal in hand and a nauyaca de arbol (Bothrops nigriviridis) dead at his feet. Juan said he first saw the snake on a palm leaf within striking distance of his face.”
The specimen Juan spotted would later end up in the hands of American Herpetologist Hobart Smith who, together with John Lynch, reported it and two others from above Zanatepec, Oaxaca, as Bothrops nigroviridis aurifer.
A 60-year-old “retired” John Stuart Rowley, Jr. is enjoying the very brand of retirement most naturalist dream of. John Jr. was in the same largely uncharted corner of Oaxaca, in a mountain range known as the Sierra Atrevesada – an east-west running range forming the northwestern edge of the Sierra Madre de Chiapas.
A decade earlier he’d sold his shares in a weighing machine business in California to pursue his lifelong passion: birds. With those funds and support from the American Museum of Natural History and other institutions, Rowley embarked on a series of collecting trips into southern Mexico. His efforts produced an ornithological treasure trove – yielding over 20 publications, countless photographs, observations and the discovery and description of the brilliant, Blue-capped Hummingbird (Eupherusa cyanophrys).
After being among the first investigators to access the dense forests of the Sierra Atrevesada in an ornithological reconnaissance the previous year, Rowley was now on his second excursion with a more diverse group of naturalists in tow. They spent the day surveying a ridge running north of Rancho Vicente, some 8 kilometers west of the ~2000-meter-tall Cerro Baul. Among the day’s collection: a single Scaled antpitta (Grallaria guatimalensis guatimalensis), a Zorzal Corona Negra (Catharus mexicanus) and a Stripe-tailed hummingbird (Eupherusa eximia). While in pursuit of their feathered quarry, a second hummingbird species, Campylopterus rufus, was spotted darting nervously in a dense palm thicket. Closer inspection revealed the bird was reacting to a green pitviper coiled along the stalk of the palm. The bird later went on its way, but the snake was secured and preserved.
The viper would catch the attention of 62-year-old American herpetologist, Charles Mitchill Bogert — curator of the American Museum of Natural History. Though waist-deep in Oaxacan herpetofauna at the time, Chuck was apparently unaware of MacDougall’s specimens from 17 years earlier. He recognized Rowley’s pitviper as distinct and worked to describe it as a new species, later writing: “The differences are so marked that it can scarcely be doubted that the specimen from Oaxaca represents an undescribed species. It will bear the name of the veteran ornithologist, Mr. J. Stuart Rowley, whose competence, enthusiasm, and perseverance in the field have contributed so much to our knowledge of the fauna of southern Mexico”
Unfortunately, John Stuart Rowley Jr. would never see his namesake viper formally described. His body was found at the base of a cliff in the Sierra de Cuatro Venados just west of Oaxaca City on May 7th, 1968 – purportedly the result of an accidental fall. However, members of Rowley’s family have maintained for decades that he was murdered – pushed from the cliff then robbed of his expensive camera equipment.
Four months later, Chuck Bogert’s publication introduced the world to Rowley’s Palm Pitviper, Bothrops rowleyi (now Bothriechis rowleyi).
The next year, Hobart Smith and Edward Moll revisited Don Tomás’ specimen from Cerro Azul. Owing to its higher number of dorsal scale rows and differences in habitat, the pair concluded this original specimen represented the distinct species, Bothrops macdougalli.
The following decades would see B. macdougalli, with its lone specimen from Cerro Azul, synonymized with Bothriechis rowleyi. The species proved to be a relatively rare one with only roughly a dozen specimens reported across the Sierra Madre de Chiapas in Oaxaca and the Northern Highlands of Chiapas.
In 2013, HERP.MX Field Team's Chris Grünwald secured three additional specimens from Chiapas' northern highlands — the first reported in over 30 years. To-date, we’ve observed roughly two dozen specimens in the region, so early last year when the winter was feeling particularly cold and long, the team knew where to go for a reliable palm pitviper fix. What we hadn’t counted on was that among the trip’s by-catch would be an undescribed species of Evergreen Forest Stream Treefrog (Quilticohyla sp.)
Caught once again with the dry season blues, the HERP.MX Field Team decided it was the perfect season to secure additional frog specimens. Of course, if some Bothriechis happened to get in the way, no one would complain.
A full day's worth of driving would put HERP.MX Field Team members, Ricardo Ramírez Chaparro and Carlos Montaño in Chiapas' northern highlands. After fueling up with a traditional breakfast, the two hit the cloud-forest with a slow start.
As the sun went down, Ricardo and Carlos' luck improved. First a sleeping Anolis sp. was spotted on a leaf; and a handful of amphibians made an appearance — though not the target. As the team moved down a slope to a back-up site for the new species of treefrog, Ricardo glanced back to catch a neonate Rowley's Palm Pitviper (Bothriechis rowleyi) in his flashlight beam as it crawled along the trunk of a tree.
Once in the arroyo, the good luck kept flowing with the appearance of three species of treefrog, including the trip's "target": the undescribed Quilticohyla. Now with the objective in-hand, the pair retired for the night to get an early start the next morning.
With the pressure to collect additional frog samples relieved, Ricardo and Carlos hit the hillsides and canyons with their eyes set on finding additional Rowley's Palm Pitvipers (Bothriechis rowleyi). They weren't disappointed when a mix of juvenile and adult specimens were spotted along the edges of an arroyo.
Having scratched the palm pitviper itch, the HERP.MX Field Team started the day-long drive back home.
Thanks to Robert Hansen, Dan Wylie, and Mark Jennings for their help with portions of this report.
