Polystichum filiorum, a narrow endemic from western Dominican Republic
Hispaniola has been on my "to-do" list for fern collecting for several years now, and I finally got the opportunity to go (with a lot of support from the Jardín Botánico Dr. Rafael María Moscoso in Santo Domingo)! I've become increasingly interested in the Caribbean in the last few years, as I have become more aware of the spectacular endemism in the region and the fact that a large number of type collections of widespread taxa were made in the West Indies. This later point has become particularly important as I've started to work in some widespread Neotropical species complexes - obviously, including material from at or near type localities is critical for such work. I was finally able to make some progress towards working in the area in the spring of 2018, when I met several of the directors of national botanical garden of the Dominican Republic at a meeting in Havana, Cuba. Over the course of several months following that meeting, we developed a plan for a future visit to work in the herbarium, offer a short course in fern biology for students, and do fieldwork in the mountains of the country's western region. Thanks to a tremendous amount of help from Yuley Encarnación Piñeyro, the manager of the national herbarium, I was able to navigate the permitting process with relative ease, and things were set for a trip in the first half of December.
On this trip, I was joined by Lindsey Riibe (University of Florida), Susan Fawcett (University of Vermont), Sally Chambers (Marie Selby Botanical Gardens) and Pedro Schwartsburd (Universidade Federal do Viçosa), all of whom work on various groups of ferns. Our plan was simple: start with a few days in the national herbarium to familiarize ourselves with the flora and localities, rent two trucks and head towards the border with Haiti to collect in the Sierra de Neyba and Sierra de Baoruco for a week, and then offer a short course on fern systematics to university students in Santo Domingo. As none of us had prior experience in the Dominican Republic, our success was dependent largely upon our friends in the herbarium, especially Yuley and the two resident field botanists, Teodoro Clase and Yommi Piña, who would accompany us on the trip. Despite some minor hiccups at the start of the trip (apparently reserving a 4x4 at a car rental agency in Santo Domingo does not ensure that you will get one) we were on the road soon enough, headed towards the limestone mountains of the country's southwest.
A huge Pityrogramma ebenea!
Thanks to Teodoro's field experience, infallible memory, and penchant for 18 hour work days, what followed was one of the most efficient field trips I have participated in. Each of us had a list of "wanted" species, and after several long discussions in the herbarium and on the road, Teodoro and I hashed out an itinerary that would maximize our chances of finding those species. As I would find out along the trip, Teodoro not only knew the species and the localities we were looking for, he knew exactly where to find each species at each site (this knowledge appears to hold for the entirety of the Dominican Republic)!
Our route was simple: we headed along Route 44 through Barahona Province, following the curving coast past Barahona and Enriquillo towards Pedernales Province and Parque Nacional Jaragua, which encompasses a spectacular dry scrubland laid over dogtooth limestone. From there, we pushed north along the abandoned roads of the ALCOA bauxite mining operation to reach the famed collection locality "Las Abejas", then followed the same route back to the town of Pedernales before heading north along the International Highway (which is closer to a cart path than a highway) to several localities along the Haitian border. We passed through Parque Nacional Sierra de Baoruco, crossed the depression at Lago Enriquillo, and then headed back into the mountains of the Sierra de Neyba, slowly heading eastward towards Santo Domingo. Throughout the trip, the botany was fantastic, though the ferns were quite patchily distributed - most were restricted to patches of wet montane forest surrounded by agricultural land and dry lowland forest. This made for a hit-and-run collecting trip - load your collecting bag at one site and drive 5 hours (which covered about 30 km, between the quality of Dominican mountain roads and our chronically faltering Mitsubishi pickup) until you find another humid bend in the road. I found most of the lycophytes I was looking for, and our two PhD students, Lindsey and Susan, had phenomenal success tracking down their respective queries, Polystichum (Dryopteridaceae) and Goniopteris (Thelypteridaceae). Having a trip focused largely on these two groups was a great opportunity to compare and contrast two groups with similar evolutionary histories played out in different habitat types. The Hispaniolan species of both genera belong to Caribbean-endemic clades of 30-40 species that appear to have undergone a recent radiation in the West Indies, where they are mostly restricted to limestone outcrops and calcareous soils associated with these outcrops. Despite these similar evolutionary trajectories, the taxa rarely grow side-by-side; Polystichum species tend to be restricted to relatively humid microsites in the forest understory where they grow on boulders and talus slopes, whereas most of the Goniopteris species were found on open disturbed roadbanks, where they would typically grow with Christella, Begonia, Lantana, and other "tropical ditch" taxa. Interestingly, many species in both genera proliferate vegetatively via the production of buds on their leaves; perhaps this is an adaptation to promote colonization of a given microsite, considering the high habitat specificity of most species?
Phlegmariurus cf hartwegianus
The richness of plant diversity in the wet forests of the Sierra de Neyba and the Sierra de Baoruco contrasted sharply with the abject poverty in which many people along the Dominican/Haitian border. Despite the abundance of military outposts in the region and active efforts to patrol their extensive border, most of the people living on the Dominican side of the frontier were Haitians. Though some have lived in the Dominican Republic for several generations, most are recent migrants seeking better opportunities in the relatively wealthy Dominican Republic. Most of the people we saw seemed to be working as subsistence farmers or as migrant farm laborers; others seemingly had no employment. Homes along the border are almost uniformly small shelters made from scavenged wood, plastic, and sheet metal; running water and electricity are absent from huge swaths of the region. Antihaitianismo has a long-standing history in the Dominican Republic, and was cultivated to the level of state policy under the Trujillo regime, culminating in the Parsley Massacre in October, 1937. Tensions clearly are still high in the area today, and seem exacerbated by ongoing issues - Dominicans cite the loss of forest to Haitian squatters within Dominican protected areas amongst their principal complaints. Even so, Dominicans and Haitians in the area clearly depend on each other to survive in this isolated area - we even saw a informal international market where Haitians carried crops over the border on mules to sell to Dominican merchants, who loaded the goods on trucks to sell in nearby towns.
Goniopteris alata with lots of proliferous pinna apices!
Following our field trip, we taught a one-day workshop on fern systematics and field identification with students from several universities (mostly the Universidad Autónoma de Santo Domingo). The course was supposed to take place at a reserve about 2 hours from Santo Domingo, but due to a last-minute transportation issue, we changed venues to the national botanical garden, which has a fern pavilion! Twenty eight students participated in the course, and they brought with them an impressive background of knowledge on the local fern flora and general vascular plant taxonomy. We started in the gardenwith family-level ID in the field and then moved to the herbarium to examine micro-characters (rhizome scales, spore color, leaf venation patterns) under the stereoscope. I was really impressed by the students' enthusiasm and knowledge, and am looking forward to teaching a longer version of the course some time in the future!