Sierra De Bahoruco Research Articles

Gesneriatuberifera (Gesneriaceae), a new lithophytic species from the Sierra de Bahoruco, Barahona Peninsula of southern Hispaniola (Dominican Republic).

A narrowly endemic new species of Gesneria is described from the Sierra de Bahoruco in the Dominican Republic's Barahona Peninsula of southern Hispaniola. Gesneriatuberifera J.L.Clark & T.Clase, sp. nov. differs from all other congeners by the presence of a tuber and tubular red corollas with yellow lobes. Images and a discussion are provided to summarize the presence of tubers in other Gesneriaceae and differentiate Gesneriatuberifera from congeners that share a lithophytic habit. Based on IUCN guidelines, a preliminary conservation status of Endangered (EN) is assessed for G.tuberifera.

Avian use of avocado farms and intact forest in the northern Sierra de Bahoruco, Dominican Republic

Avian use of avocado farms and intact forest in the northern Sierra de Bahoruco, Dominican Republic

Dominican Larimar Mining—Current State and Future Prospects

This paper presents basic mineralogical and petrological data of the rocks hosting larimar deposit from the Sierra de Bahoruco, in the SW part of the Dominican Republic. Larimar is a unique ornamental stone with a wealth of decorative qualities. The Las Filipinas Larimar Mine in Barahona Province is the only place of this type in the world. Its production and distribution require radical action; hence, the paper also provides current information on the extraction of this raw material and prospects for the future. The paper indicates the possibility of using a new adit support system based on a mixed support (arch support and shotcrete). Numerical analysis shows the need to create a shotcrete coating around the entire circumference, about 15 cm thick. The variable geotechnical situation around the excavation, caused by the planned operation, prompts the use of slightly different solutions in the field of support. The article presents an outline of the technology using Polish experience. It is a support-bolt casing system with the latest achievements in this field.

Phylogenetics of Leptocereus (Cactaceae) on Hispaniola: clarifying species limits in the L. weingartianus complex and a new species from the Sierra de Bahoruco.

The Antillean genus Leptocereus represents an in-situ radiation among the Greater and Lesser Antilles of 19 currently recognized species. Extensive fieldwork carried out in the Dominican Republic over recent years has revealed that the species limits of Leptocereus of Hispaniola are more complex than previously thought. There are four currently recognized species that occur on the island, L. demissus, L. paniculatus, L. undulosus and L. weingartianus. We evaluate species limits in this group based on DNA sequence data and phylogenetic analysis, morphological characters and a survey of herbarium specimens from across Hispaniola. Based on our analyses, it is clear that at least five species occur on the island of Hispaniola, with the new species from Sierra de Bahoruco, L. velozianus, described here. We provide an identification key, distribution maps and photographic plates for all species on Hispaniola based on our own fieldwork and the study of herbarium specimens. The description of yet another species of Leptocereus on Hispaniola reiterates the importance of the poorly studied, but yet biodiverse, seasonally dry tropical forest in the Antilles.

Active tectonics along the Cul-de-Sac – Enriquillo plain and seismic hazard for Port-au-Prince, Haiti

The active faults in Haiti were not well known and no detailed mapping of active fault traces was available before the 2010, M7.0 earthquake. The lack of detailed fault mapping hindered the interpretation of the event and the seismic hazard assessment. Here, using high-resolution LIDAR topography, aerial photographs, bathymetric charts, together with geological data complemented with field observations, we carried out a morphotectonic analysis at a variety of scales. We analyzed the drainage network at the northern front of the Massif de la Selle – Sierra de Bahoruco (MSB) by mapping the fans of the main rivers and their associated drainage basins. We found that the areas of all the fans were compatible with the sizes of their drainage basins, except the paleofan of Port-au-Prince. We interpret that this paleofan has been offset by 7.9±0.3km across the main strike-slip Enriquillo-Plantain Garden Fault (EPGF) and we estimate a minimum horizontal slip rate of ∼3mm/yr over the Pleistocene. Moreover, in the Cul-de-Sac – Enriquillo plain, within which the capital city of Port-au-Prince is located, we mapped numerous NW-SE to WNW-ESE-striking Quaternary folds and thrust faults. Some of the thrust faults are north-dipping and located to the southern front of the Matheux-Neiba Lower Miocene fold. Other thrusts, such as those near Ganthier, Jacquet, Nan Cadastre, and Port-au-Prince, are south-dipping and located along the northern front of the MSB Lower Miocene fold. Previously, Saint Fleur et al. (2015) showed that the 2010 Haiti earthquake activated both one of the young thrusts (Lamentin) and the EPGF, consistent with oblique convergence between the Caribbean and the North American plates.

On the relationship among birds and Trema micrantha in montane forests of Hispaniola

Avian frugivores are of great interest to ecologists because they play an important role in ecosystem functioning, and can serve as important components in habitat restoration. In the Neotropics, observational studies have demonstrated the importance of a variety of fruit trees to numerous bird species, but undoubtedly other tree species exist that are a key resource for birds. I explored the relationship between Trema micrantha (L.) Blume, which produces superabundant fruit nearly continuously, and its disperser assemblage in Hispaniolan pine forest and montane broadleaf forest in the Sierra de Bahoruco, Dominican Republic. In 174 hours of observation at sixteen trees I recorded 513 visits by nineteen species of birds. Birds did not visit Trema in numbers reflecting their relative abundance in each habitat. The most frequent consumer of Trema fruit was the migratory Cape May Warbler, Setophaga tigrina (Gmelin, 1789), but other frequent visitors included the Black-throated Blue Warbler, S. caerulescens (Gmelin, 1789), and the endemic Palmchat, Dulus dominicus (Linnaeus, 1766), and Hispaniolan Highland-Tanager, Xenoligea montana (Chapman, 1917). I recorded 85 aggressive interactions among nine species of birds in Trema trees, with female Cape May Warblers involved in most of these. There was no evidence that Trema was dependent on any one species of bird for dispersal of its seeds, and despite the large proportion of visits by the Cape May Warbler, I found no evidence that any species of bird was dependent upon fruit from Trema. Rather, because male Cape May Warblers dominate females and defend nectar sources in these habitats, I suggest that for female Cape May Warblers, these scattered Trema trees represent a known, reliable, and accessible source of food which they can defend. Trema trees will benefit these bird species as a food resource, but may also function as a target for many other birds moving across the landscape, thereby facilitating the dispersal of a wider variety of seeds and the restoration of deforested sites.

Miconia clasei, a New Species of Miconia sect. Calycodomatia (Miconieae: Melastomataceae) from the Sierra de Bahoruco, Dominican Republic and a Closer Look at Species Relationships in the Sandpaper Clade

Recent collections in the Sierra de Bahoruco represent a previously undescribed species of Miconia sect. Calycodomatia from the Greater Antillean Sandpaper clade. We herein describe the new species as Miconia clasei, provide a phylogenetic analysis to determine close relatives, and compare it morphologically with its closest relatives and phenetically similar taxa. We also expand on previous analyses of the Sandpaper clade, including more individuals per species than previously analyzed, and two taxa never before analyzed phylogenetically. We show that several species within the Sandpaper clade are indeed cladospecies, while others appear to be non-monophyletic.

The basaltic volcanism of the Dumisseau Formation in the Sierra de Bahoruco, SW Dominican Republic: a record of the mantle plume magmatism of the Caribbean Large Igneous Province

The Dumisseau Formation outcropping in the Sierra de Bahoruco offers the opportunity for studying on land the mantle plume magmatism generator of the Caribbean Large Igneous Province (CLIP) during the Late Cretaceous. It consists of a sequence of about 1.0-1.5 km-thick mainly composed of mafic basaltic flows and pyroclastic deposits, with subordinated volcanogenic sedimentary deposits and syn-volcanic doleritic sills and dikes. All the volcanic rocks were erupted or re-sedimented in relatively deep-marine conditions, as evidenced by the rare interbedded chert and pelagic limestone. On the basis of the MgO, TiO2 and incompatible trace elements contents three geochemical groups have been identified in the Dumisseau Formation: low-Ti tholeiites; high-Ti or transitional basalts; and high-Ti and LREE alkaline basalts. Geochemical modelling indicates a derivation from melts generated and incorporated at different depths in the mantle, which is consistent with the processes that take place during the rise of a mantle plume beneath the oceanic crust. Two 40Ar/39Ar whole-rock ages indicate the extrusion of magmas at least in the 92-74 Ma time interval (Turonian-Coniacian boundary to Maastrichtian), resulting coeval with the formation of the CLIP. As a result, the Dumisseau Formation is an emerged fragment of the CLIP, with which it must have continuity through the Beata Ridge. These rocks are unconformably overlain by carbonate red algae facies of the middle-upper Eocene, constituting the volcanic basement of the Sierra de Bahoruco.

Home Range Size and Nocturnal Roost Locations of Western Chat-Tanagers (Calyptophilus tertius)

Western Chat-Tanagers (Calyptophilus tertius) are a rare and globally vulnerable songbird endemic to the island of Hispaniola. We conducted a radio-telemetry study of non-breeding Western Chat-Tanagers at two adjacent cloud forest sites in Sierra de Bahoruco in southwestern Dominican Republic during March and April of 2010. Male home ranges averaged 2.18 ± 0.25 ha in size (n = 4) and were significantly larger than those of females (0.88 ± 0.04 ha; n = 2). However, core use areas did not differ significantly between the sexes. We assumed that males and females with overlapping home ranges were mated pairs. At night, two putative pairs roosted an average distance apart of 15.8 ± 3.5 m (n = 7 observations).

Origin and model formation of the semi-precious Larimar stone in the Sierra de Bahoruco, Dominican Republic

The investigation of the origin and evolution of the Larimar gemstone in the Dominican Republic has required the same scientific tools as used for some valuable metal deposits. This singular stone is the consequence of various processes that determine, firstly, the emergence of a pectolite without any aesthetic value, and then the conditions are modified until finally an outstanding product is obtained due to its coloration. The process in the Hispaniola Island begins in the Upper Cretaceous with basaltic lava emissions which create an oceanic “plateau” in the Checheses Larimar area, then emerge and, with the help of the deposition of organic materials, produce a hydrothermal alteration of the volcanic pile producing a pectolite concentration with a blue coloration suitable for use in jewelry. The Miocene-Pliocene tectonic changes its primitive structure until the current form is configured, whilst at the same time the hidden volcanic material crops out below a thick Eocene sedimentary series.

A new species of the hysius species-group of Calisto Hübner (Lepidoptera, Nymphalidae, Satyrinae) and insights into the status of different populations currently attributed to C. grannus Bates

A species belonging to the hysius group of Calisto is newly described. Calisto bahoruco new species inhabits the easternmost area of the southern Hispaniola Sierra de Bahoruco. The species is closely related to C. hysius Godart, another endemic from the southern mountains. The two species differ in average forewing length (larger in C. hysius), the relative size of ocelli (larger in C. bahoruco), and in the darker ground color with more contrasted paler edges of lines at underside of wings in C. bahoruco compared to C. hysius. Their male genitalia differ in the shape of the uncus and in the heavier sclerotization in C. bahoruco. COI barcodes bear a minimum of 15 differences between the two species. All species delimitation methods applied to the COI dataset, ABGD, BIN, bPTP, mPTP, and PTP yielded 8 species. The exception was the GMYC that failed to recognize the new taxon and oversplitted several other taxa. COI gene tree obtained by Maximum Likelihood and Bayesian have identical topologies agreeing with a multilocus phylogeny reconstructed in a previous work on Calisto and placing the new taxon as sister of C. hysius. Additionally, we provide new evidence of the conspecific nature of all named populations within Calisto grannus group.

Two new species of Henriettea (Melastomataceae, Henrietteeae) for the flora of the Greater Antilles

Two new species of Melastomataceae are described and illustrated: Henriettea sierrae from the mountains of eastern Cuba, and Henriettea multigemma from the Sierra de Bahoruco in the Dominican Republic, Hispaniola. Both species belong to the complex of squamous Henriettea species endemic to the Greater Antilles. Henriettea sierrae is distinguished by its ciliate leaves, foliose bracteoles at the base of the flowers, and lanceolate petals with lateral teeth in their apical third. Henriettea multigemma is distinguished by its fascicles of numerous flowers that are borne of suberose protuberances formed by multiple flower buds in the leafless nodes of the stems, and by the presence of leaves with apical domatia.

Petrographic and mineralogical studies of fossil charcoal from Sierra de Bahoruco (Barahona Province, Dominican Republic)

The volcanic formations of the Sierra de Bahoruco mountain range (Barahona Province, Dominican Republic) contain charred fragments of plants, mainly tree trunks, which are composed of dense concentrations of hard mineralized fusain, with diverse microstructures. Petrographic examinations confirmed occurrence of two types of fusinite - structural fusinite with well-preserved tree tissue fragments, and detrital fusinite originating probably from softer tissues of tree phloem. In addition to the fusinite varieties developed from tree trunks and roots, charred tissues of dead external part of trunk epidermis affected by the microbiological process of rotting were identified. Poorly marked seasonal growth rings of trees, the shape and distribution of tree tissues, as well as the degrees of tissue destruction, indicated that the fragments originated from tropical trees growing in specifically marked rain and dry seasons, while wood tissues, charred by the fall of hot volcanic dust, suggested the existence of a monsoon tropical forest on the area. Fusinite was strongly impregnated with calcite and pectolite, sometimes zeolites (prehnite) and chlorite. It was accompanied by iron and copper sulphides, i.e. pyrite, chalcopyrite, and chalcocite. The latter minerals occurred in magma and pyroclastic formations, strongly associated with hydrothermal activities.

A New Species ofPhyllophaga(Coleoptera: Scarabaeidae: Melolonthinae) from the Dominican Republic

ABSTRACT Phyllophaga delphinicauda, new species (Coleoptera: Scarabaeidae, Melolonthinae), is described from the eastern Sierra de Bahoruco in the Dominican Republic. Supportive taxonomic and biogeographic information is presented in a discussion of the new species' apparent relationship to Phyllophaga davidsoni Woodruff, 2004, and Phyllophaga carnegie Woodruff, 2004. The potential geographic and temporal distributions of P. delphinicauda are examined and its status as a species of conservation concern is discussed. A modification to the existing key to the Phyllophaga of Hispaniola (Woodruff 2004) is presented to accommodate this new species.

Physicochemical analysis of Lake Enriquillo in Dominican Republic

The water level in Lake Enriquillo in the Dominican Republic (DR) has increased by an unprecedented amount over the last decade, inundating thousands of acres of farmland and more than a dozen villages and inflicting adverse social, environmental, and economic impacts on the nation. The Lake Enriquillo Basin (LEB), located near the towns of Independencia and Bahoruco in the southwest region of the DR, is bordered to the north by the Sierra de Neyba mountain range and to the south by the Sierra de Bahoruco mountain range. Lake Enriquillo is hypersaline and endorheic, with a water level that normally fluctuates between 40–50 m below sea level (BSL). However, since 2000, both Lake Enriquillo and Lake Azuei (Sumastre) in Haiti have experienced alarming water level increases, with Lake Enriquillo’s water level rising to 17.2 m BSL This article explores the changes in some of the important physicochemical parameters—such as salinity, dissolved oxygen, temperature, and pH—that have occurred in the period from 1977 to 2012. The highest salinity value occurred in 2012, at a value 103.1‰, with an average increase of 27.06‰, coinciding with the lake level of 17.2 m BSL. Changes in these parameters have caused damage to the ecosystem and the lives of people and species that inhabit the region.

New Hispaniola locality record for the endemic beetle Nicrophorus hispaniola Sikes & Peck, 2000 (Coleoptera: Silphidae: Nicrophorinae)

The endemic Hispaniolan beetle Nicrophorus hispaniola Sikes & Peck, 2000, is reported from the locality of Zapotén, Sierra de Bahoruco, Dominican Republic, a national park outpost near the border with Haiti. This species appears restricted to Sierra de Bahoruco and Sierra de Neiba in the southwestern corner of the Dominican Republic.

The basaltic volcanism of the Dumisseau Formation in the Sierra de Bahoruco, SW Dominican Republic: A record of the mantle plume-related magmatism of the Caribbean Large Igneous Province

The basaltic volcanism of the Dumisseau Fm in the Sierra de Bahoruco, SW Dominican Republic, offers the opportunity to study, on land, the volcanism of the Caribbean Large Igneous Province (CLIP). It consists of an at least 1.5km-thick sequence of submarine basaltic flows and pyroclastic deposits, intruded by doleritic dykes and sills. Three geochemical groups have been identified: low-Ti tholeiites (group I); high-Ti transitional basalts (group II); and high-Ti and LREE-enriched alkaline basalts (group III). These geochemical signatures indicate a plume source for all groups of basalts, which are compositionally similar to the volcanic rocks that make up various CLIP fragments in the northern region of the Caribbean Plate. Trace element modelling indicates that group I magmas are products of 8–20% melting of spinel lherzolite, group II magmas result 4–10% melting of a mixture of spinel and garnet lherzolite, and group III basalts are derived by low degrees (0.05–4%) of melting of garnet lherzolite. Dynamic melting models suggest that basalts represent aggregate melts produced by progressive decompression melting in a mantle plume. There is no compositional evidence for the involvement of a Caribbean supra-subduction zone mantle or crust in the generation of the basalts. Two 40Ar/39Ar whole-rock ages reflect the crystallisation of group II magmas at least in the late Campanian (~74Ma) and the lower Eocene (~53Ma). All data suggest that the Dumisseau Fm is an emerged fragment of the CLIP, which continues southward through the Beata Ridge

Distribution patterns of endemic flora to define hotspots on Hispaniola

Nineteen areas on the island of Hispaniola (Haiti and the Dominican Republic) were studied with the aim of determining the distribution pattern of the endemic flora in these areas, and their variability with altitude. The main concentration of endemic species occurs in mountains with a medium altitude and in certain mountain sites (palaeo-islands), which coincide with hotspots; a lower number of endemics are found in low-lying areas (coldspots), due to the degradation of their habitats. A total of 1,582 endemic species were studied and were distributed in 19 areas. The whole island is of outstanding interest for its richness in endemics; it has 2,050 endemic species, representing 34.16% of its total flora. The territory in the study is home to 1,284 genera of which 31 are endemic to the island, including monotypical genera such as Tortuella abietifolia Urb. & Ekman, and endemic genera such as Hottea, containing seven endemic species. The sites with the highest rate of endemics are area A16 in the central range with a total of 440 endemic species, of which 278 are exclusive to the territory; and the Sierra de Bahoruco, la Selle, La Hotte and Tiburón in area A12, where we found 699 plants of which 482 are endemic and exclusive to the area; and A13 with 173 and 129 respectively. This work highlights the exceptional floristic diversity in endemic species and genera and analyses their distribution patterns as a tool for conservation in this area of the world, whose high endemicity rate makes it one of the most significant hotspots in the Caribbean.

Assessing conservation status of resident and migrant birds on Hispaniola with mist-netting.

We analyzed temporal trends in mist-net capture rates of resident (n = 8) and overwintering Nearctic-Neotropical migrant (n = 3) bird species at two sites in montane broadleaf forest of the Sierra de Bahoruco, Dominican Republic, with the goal of providing quantitative information on population trends that could inform conservation assessments. We conducted sampling at least once annually during the winter months of January–March from 1997 to 2010. We found evidence of declines in capture rates for three resident species, including one species endemic to Hispaniola. Capture rate of Rufous-throated Solitaire (Myadestes genibarbis) declined by 3.9% per year (95% CL = 0%, 7.3%), Green-tailed Ground-Tanager (Microligea palustris) by 6.8% (95% CL = 3.9%, 8.8%), and Greater Antillean Bullfinch (Loxigilla violacea) by 4.9% (95% CL = 0.9%, 9.2%). Two rare and threatened endemics, Hispaniolan Highland-Tanager (Xenoligea montana) and Western Chat-Tanager (Calyptophilus tertius), showed statistically significant declines, but we have low confidence in these findings because trends were driven by exceptionally high capture rates in 1997 and varied between sites. Analyses that excluded data from 1997 revealed no trend in capture rate over the course of the study. We found no evidence of temporal trends in capture rates for any other residents or Nearctic-Neotropical migrants. We do not know the causes of the observed declines, nor can we conclude that these declines are not a purely local phenomenon. However, our findings, along with other recent reports of declines in these same species, suggest that a closer examination of their conservation status is warranted. Given the difficulty in obtaining spatially extensive, long-term estimates of population change for Hispaniolan birds, we suggest focusing on other metrics of vulnerability that are more easily quantified yet remain poorly described, such as extent of occurrence.

Contribución al conocimiento de las aves en Hoyo de Pelempito, Sierra de Bahoruco, República Dominicana

Se realizó un inventario de las especies de aves presentes en el Hoyo de Pelempito, Sierra de Bahoruco. Mediante el uso de puntos de conteo se registró un total de 991 individuos, 41 especies y 17 familias de aves, encontrándose que 13 especies son endémicas, 18 residentes, nueve migratorias y dos introducidas. Seis especies se consideran amenazadas, entre estas se pueden citar el caso de la Cotorra (Amazona ventralis) y el Perico (Psittacara chloroptera). Las aves insectívoras y omnívoras fueron las más abundantes, mientras que las nectarívoras, granívoras, carnívoras y frugívoras se presentaron en menor proporción.