Botanical Exploration of the Mache-Chindul Mountains, Northwestern Ecuador
David A. Neill
Missouri Botanical Garden, 4344 Shaw Blvd., St. Louis, MO 63110
John L. Clark
Biology Department, George Washington University, Washington, DC 20052
Homero Vargas and Tamara Nuñez
Herbario Nacional del Ecuador, Quito, Ecuador
This is the Final Project Report submitted in March, 1999 to the
National Geographic Society, Committee for Research and Exploration, for NGS Grant # 5857-97.
We carried out an intensive inventory of the flora of the Mache-Chindul mountains, which comprise the northern portion of the Pacific coastal range of western Ecuador. During the field studies, we obtained more than 4,000 herbarium collections. About 1,100 species of vascular plants have been identified to date from our collections; many more species will be added to the current checklist as the remaining specimens are identified by taxonomic specialists at herbaria around the world who will receive duplicate specimens. We also carried out quantitative ecological studies of forest composition and structure, establishing three one-hectare permanent research plots in primary forest at Bilsa Biological Station, a privately-owned reserve of 4000 hectares in the eastern portion of the Mache-Chindul mountains.
Our botanical explorations in the Mache-Chindul mountains resulted in the discovery of a number of plant species new to science, and one new genus, Ecuadendron, in the legume family Fabaceae; subfamily Caesalpinioideae. Ecuadendron acosta-solisianum, described and published by David Neill in 1998, is a large canopy tree with 2-meter long inflorescences and flowers adapted to pollination by bats. It is now know from just three localities in western Ecuador: one in the Mache-Chindul mountains, and two localities 350 km to the southeast at the western base of the Andes. Two additional new species have been described from the collections made by John Clark at the Bilsa Biological Station; Pitcairnia clarkii (Bromeliaceae), an epiphyte, and Rustia bilsana (Rubiaceae). Publication of several additional new species from our collections are being prepared by various plant taxonomists who are specialists in different groups of vascular plants.
Our fieldwork in the Mache-Chindul mountains was interrupted for a year by the 1997-1998 El Niño event, the most severe El Niño of the 20th century, with heavy rains which caused severe flooding and destroyed roads and bridges throughout coastal Ecuador and Peru. The flooding and road destruction prohibited access to the areas of primary forest in the range which were the target of our fieldwork. After El Niño subsided, in the second half of 1998, we continued our field activities, concentrating on the southern portion of the Mache-Chindul mountains and the range to the south, the Jama mountains, in northern Manabí province. This area has a drier climate than the central portion of the Mache-Chindul mountains and is more readily accessible from paved highways. In the southern part of the study area, we made collections in lowland tropical moist and dry forest. Our field studies allow us now to define much more precisely the geograpical extent of different vegetation types in coastal Ecuador – wet, moist, and dry forest. Our botanical collections resulted in extensions of the known geographical range of many plant species: many dry forest species are at the northern limit of there range in the area we studied, and many wet forest species are at the southern limit. We also found an area of 5000 hectares of undisturbed, intact lowland moist forest along the coast just south of the equator. This site, we believe, is the largest remaining fragment of the moist forest vegetation type in remaining in western Ecuador. The owner of the moist forest site has expressed his intent to preserve it as intact forest, and we have agreed to help him, with our infomration on the flora and vegetation of the site to help with the legal declaration of the site as a private forest reserve and register it with Ecuador’s Ministry of the Environment
The results of our studies of the flora and vegetation in the Mache-Chindul mountains are being presented to Ecuadorian government agencies, including the Ministry of the Environment which administers the Mache-Chindul Ecological Reserve, and two non-governmental conservation organizations, the Jatun Sacha Foundation which owns and administers the Bilsa Biological Station, and the Tercer Mundo Foundation which administers the Cerro Pata de Pájaro Protection Forest.
The coastal region of Ecuador has become known, over the past several decades, as a region of high biological diversity and endemism, and also as a prime example of the world’s conservation "hotspots" where high biodiversity coincides with high rates of human-caused destruction of native ecosystems and consequent endangerment of endemic species. One of the first botanical studies in the region was Elbert Little’s illustrated book on the common trees of Esmeraldas province (Little & Dixon, 1969). In the 1970’s, botanists Calaway Dodson and Alwyn Gentry carried out a floristic survey of the Río Palenque Science Center, a lowland wet forest site in the fertile soils of the Guayas River valley. They encountered many species new to science in the small 100-hectare forest remnant at Río Palenque, which is now surrounded by agricultural crops and is one of very few tiny forest remnants in the valley. Their illustrated Flora of Río Palenque (Dodson & Gentry, 1978) was followed by the Flora de Jauneche, a moist forest site (i.e., intermediate along a moisture gradient between wet and dry forests) (Dodson et al., 1985). Dodson and Gentry also worked on a manuscript for a third floristic study, the dry forest at Capeira near Guayaquil, but this work was incomplete at the time of Al Gentry’s death in a plane crash west of Guayaquil in 1993, and remains unpublished.
Dodson and Gentry’s botanical surveys in western Ecuador during the 1970s and 1980s were mostly concentrated in the Guayas River valley. The coastal range of mountains west of the Guayas basin, especially the northern part of the range in western Esmeraldas and northern Manabí provinces, remained largely unexplored until the 1990s. The northern part of the coastal range, known locally as the Mache and Chindul mountains, is higher, wetter and less easily accessible than the central and southern parts of the range. The attention of biologists was focussed on the Mache-Chindul Mountains during an expedition in 1991 organized by Conservation International through its "Rapid Assessment Program (RAP)". The 1991 RAP expedition included botanist Al Gentry, ornithologist Ted Parker, mammalogist Louise Emmons, ecologist Robin Foster, and their Ecuadorian counterparts from the National Polytechnic and Catholic Universities in Quito. The botanical surveys made by the RAP expedition confirmed the high degree of endemism in the regional flora – an estimated 20% of the plant species are endemic to western Ecuador and adjacent areas of coastal Colombia and Peru – and also that alpha diversity of woody plants, at least, is much lower than in the upper Amazon basin of Ecuador and Peru. During the expedition in the Mache-Chindul Al Gentry collected specimens from a tree which he described as a new genus and species in the Bignoniaceae family: Exarata chocoensis A.H. Gentry published the following year in 1992.
The report of the 1991 RAP expedition to the coastal range of Ecuador (Parker & Carr, 1992) was widely circulated in Ecuador and helped to stimulate the interest of conservation groups in preserving the region’s biodiversity and endemic biota. In 1994, the Jatun Sacha Foundation of Ecuador began a campaign, led by Jatun Sacha co-founder Michael McColm to raise funds for purchase of forest land. The campaign was successful, and the Jatun Sacha Foundation established the Bilsa Biological Station with 750 hectares initially; the biological station has now increased in size to more than 4,000 hectares. Ecuador’s Conservation Data Center, with support from The Nature Conservancy, carried out in 1994-95 a feasibility study for establishment of a larger, publicly-owned reserve, and in August 1996 the government of Ecuador established the Mache-Chindul Ecological Reserve, an area of about 40,000 hectares in the central part of the range, by executive decree. Meanwhile, a local conservation group based in the coastal town of Pedernales, the Tercer Mundo Foundation, lobbied for establishment of a reserve on the Cerro Pata de Pájaro, one of the highest peaks in the range, located 15 km east of Pedernales, and the Cerro Pata de Pájaro Protection Forest was decreed in May 1994. The Tercer Mundo Foundation was given ressponsiblity for management and protection of the Pata de Pájaro.
John Clark, a US Peace Corps volunteer, was assigned to the newly established Bilsa Biological Station and in September 1994 began a botanical survey of the site. Clark carried out botanical inventories for three years as a Peace Corps volunteer; he is now a graduate student in systematic botany at George Washington University.
The rapid destruction of natural habitats in western Ecuador (Dodson and Gentry, 1991) have attracted the attention of the international conservation community to the region. The Mache-Chindul mountains are one of only three fairly large tracts of intact forest that remain in coastal Ecuador (Neill, 1997) and merits more thorough biological studies in order to help develop effective conservation and management plan for the newly established Mache-Chindul Ecological Reserve and other extant forest tracts in the region.
In order to conduct more extensive botanical inventories throughout the Mache-Chindul range and adjacent areas, we applied for support from the Research and Exploration Committee of the National Geographic Society, and received NGS Grant # 5857-97 in January 1997.
During the course of this project, about 4,500 collections of herbarium collections were made in the Mache-Chindul mountains and adjacent areas. The majority of the collections were made by John Clark during his 3-year tenure as a Peace Corps volunteer. For part of this time, he was stationed at the Bilsa Biological Station, and later, was based in Quito and worked out of the National Herbarium of Ecuador as a base of operations. John also made several long treks across the mountains from east to west, collecting plant specimens along the way.
In the first half of 1997, when support from the National Geographic Society became available, Homero Vargas and Tamara Nuñez of the National Herbarium of Ecuador carried out several field trips to collect botanical specimens in the Mache-Chindul range (during this period, David Neill was at Missouri Botanical Garden in St. Louis). One of the major sites visited was the Cerro Pata de Pájaro near Pedernales in northern Manabí province, about 50 km south of the Bilsa Biological Station. Cerro Pata de Pájaro, over 800 m in elevation is probably the highest peak in the entire coastal range, and the summit is covered with a very wet cloud forest.
In addition to the general botanical survey throughout the region, we conducted quantitative ecological studies of forest structure and composition at Bilsa Biological Station, establishing three one-hectare permanent sample plots in primary forest. In each plot, a 100 m X 100 m grid was first laid out. Then tree in the plot with a diameter at breast height (DBH) of 10 cm or greater was measured and marked with a numbered aluminum tag. In a hectare of tropical wet forest, there are usuallly about 600 trees with diameter ³ 10 cm DBH. A voucher specimen was collected from the tree using extendable aluminum clipper poles. Obtaining botanical specimens from taller trees often required climbing the trunk with semi-circular, spiked tree climbers strapped to one’s feet. Voucher specimens were not collected from trees that could be positively identified in the field. Several weeks of field work were required to establish each permanent forest plot.
Clark established the first one-hectare plot at Bilsa Biological Station with the help of some volunteers. Plot 1 is located on a slope about 500 m from the main house of the Bilsa station, at about 550 m elevation. In April 1997, Clark and Nuñez established Plot 2, located on the highest peak within the Bilsa station property, at 700 m, several kilometers north of the station house. In August 1997 Neill, Vargas and Nuñez established Plot 3, located on a ridge above the headwaters of the Cube River, about 1 km west of the Bilsa station house. The three permanent plots represent the range of vegetation types present at the Bilsa station. We hoped to established a fourth study plot in forest at lower elevation, around 300 m, but could not find an appropriate site at a convenient distance from the Bilsa station; the lowlands east of Bilsa, in the Esmeraldas River valley, have been almost entirely deforested.
Our original plan was to complete the field work for the project during September-December 1997. This period is normally the dry season in the coastal range, and therefore the time of easiest access and also the period of peak flowering of canopy trees. However, 1997 turned out not to be a normal year and the dry season never arrived; the "El Niño" event began showing its effects in September, with heavy rains that continued for the following 9 months. The unpaved roads lead into the heart of the Mache-Chindul became impassable with the first rains, and access became very difficult even on mule-back or on foot. We therefore suspended the field operations of this project until after the El Niño event of 1997-98.
In July 1998, Neill started a training program in botany and conservation in Ecuador, with support from the Liz Claiborne and Art Ortenberg Foundation. The program involves post-graduate training in field reseach and conservation biology for young Ecuadorian botanists, foresters and agronomists who have completed their undergraduate studies. During August through December 1998, Neill and the Ecuadorian botany intern-trainees made several field trips to the coastal range to complete the work that had been interrupted by El Niño. All of the field work during this period was carried out in northern Manabí province, in the region around the coastal town of Pedernales. The local conservation organization, Tercer Mundo Foundation, provided logistical support and the foundation’s agroforestry extensionist Carlos Robles served as guide and helped with the field studies.
Processing and Identification of Botanical Specimens
The botanical specimens were dried and processed at the National Herbarium of Ecuador in Quito. The collection data were entered into the TROPICOS botanical database developed by Missouri Botanical Garden; the National Herbarium has a subset of the database with all the information pertinent to Ecuador. Duplicate specimens were shipped to Missouri Botanical Garden.
During April and May 1998, Vargas and Nuñez of the National Herbarium of Ecuador accompanied Neill to Missouri Botanical Garden in St. Louis. In the Missouri herbarium, the team carried out the next stage of specimen processing, sending duplicate specimens to taxonomic specialists at various botanical institutions around the world as "gifts for determination". The specialists return to Missouri Botanical Garden the species-level identification of each specimen; this information is then entered in the database and sent on to the National Herbarium of Ecuador.
Results: One Genus and Two Species New to Science
From the 4500+ botanical collections that were made in the Mache-Chindul region during the course of this project, about 1,020 species of vascular plants have been identified to date. A listing of collected species with following collection vouchers can be found in the Mache-Chindul checklist link.
As we expected at the outset of the project, a number of plant species new to science, and endemic to coastal Ecuador, were collected during the the field studies. Among the most significant botanical novelties discovered during the project is a canopy tree that is so distinctive in its floral characteristics that it has been described as a new genus; Ecuadendron, with a single species Ecuadendron acosta-solisianum D.A. Neill. This tree in the legume family (Fabaceae, subfamily Caesalpinioideaeae) has 2-meter long inflorescences that hang from the limbs, with white and brick-red flowers that are adpated to pollination by bats. The tree was first discovered at the western base of the Andes east of Guayaquil. While David Neill was preparing the publication of the new genus, John Clark found and collected it in the Mache-Chindul range, 350 km north of the first two known localities. The tree has not yet been found between the northern and southern localities. Ecuadendron is the only endemic tree genus known in western Ecuador. The new genus was published in Missouri Botanical Garden’s journal Novon in 1998; in the publication we acknowledged the support of the National Geographic Society for our field studies in coastal Ecuador that led to the discovery of the new genus.
To date, two additional species new to science have been published, based on our collections in the Mache Chindul region: Rustia bilsana Delprete (Rubiaceae), a subcanopy tree, and Pitcairnia clarkii H. Luther (Bromeliaceae). Both new species were found at the Bilsa Biological Station and collected by John Clark. We expect that a number of additional new species will be described from the Mache-Chindul collections over the next several years, as taxonomic specialists work over the specimens they have received from the project.
We also found some endemic and rare species during our fieldwork which had been known previously, but only from limited collection localities. Exarata chocoensis, a canopy tree described by Al Gentry in 1992, was found at several sites in the wet forest in and near the Bilsa Biological Station. Bauhinia haughtii, and understory shrub with bright red flowers that would is a prime candidate for domestication as an ornamental, was found in two small populations on the slopes of Cerro Pata de Pájaro. These are the only known extant populations of B. haughtii; it was originally described from a site further south in the coastal range, east of the city of Portoviejo, but has probably been extirpated from the type locality.
Advances in Phytogeography and Vegetation of Coastal Ecuador
Our field studies in the Mache-Chindul region allow us to define and map much more accurately than in the past the geographical extent of different vegetation types in coastal Ecuador. Existing vegetation maps of Ecuador will need to be corrected as a result of these studies. In terms of phytogeography and vegetation, the most significant outcome of the project has been an improved understanding of the vegetation types along the narrow coastal strip between the foothills of the coastal range and the Pacific shore. There is evidently a steep gradient of decreasing precipitation from north to south, over a relatively short distance, within a few minutes of latitude north and south of the equator.
At 15 minutes latitude north, about 40 km north of Pedernales, the natural vegetation of the coastal strip is lowland wet forest with typical canopy trees such as Virola dixonii and Brosimum utile, and with abundant epiphytes and hemi-epiphytes. The forest is being rapidly cut as colonists move into the area along the new coastal road which is under construction, and which now extends north of the Chindul River, 40 km north of Pedernales.
Travelling south along the coastal trip and approaching the equator, wet forest gives way to moist forest. The town of Pedernales, a few km north of the equator, is in the moist forest zone but the lands near the town have been deforested. We carried out extensive fieldwork in an undisturbed, mature-phase tract of moist forest at Camarones, at 4 minutes south latitude, 25 km south of Pedernales. The 5,000 hectares of primary moist forest at Camarones is owned by a rancher, Mr. Lalo Loor, who runs dairy cattle on the narrow, flat coastal plain but has allowed the forest to stand on the low foothills. The site is probably the largest fragment of tropical moist forest remaining in coastal Ecuador. Typical tree species include the large canopy palm Attalea colenda and the understory palm Phytelephas aequatorialis, both of which are endemic to the region and economically important; the latter species is the source of "vegetable ivory" which is marketed as a substitute for elephant tusk ivory. Several endemic species of legume trees were also found in the moist forest: Swartzia littlei and Inga jaunechensis; both were previously known from very few collection localities in western Ecuador. A remarkable discovery in the moist forest at Camarones was the canopy tree Exothea paniculata (Sapindaceae) which is known from the Pacific coast of Mexico and Central America, and from the Greater Antilles in the Caribbean (Jamaica, Puerto Rico, Hispaniola). This tree was found once in the Magdalena River valley of Colombia, so our record from Camarones is the second report of the genus Exothea for South America and a new generic record for Ecuador.
Continuing south along the coastal strip, moist forest is replaced by dry forest. Near the town of Jama at 14 minutes south latitude, are a few intact remnants of dry forest that are very similar to the vegetation near Guayaquil, 300 km to the south. The most conspicuous tree is the endemic Ceiba trichistandra, with its characterstic grotesquely swollen trunk and limbs that are green and photosynthetic during the long dry season. Other tree species endemic to Ecuadorian coastal dry forest, such as Machaerium millei and Pradosia montana, are also present in the forest fragments near Jama.
Quantitative Ecological Studies: Permanent Forest Study Plots
We have not yet completed identification of the all the tree species in the three permanente one-hectare forest study plots established at Bilsa Biological Station, nor have we carried out as yet the statistical analyses of the results. This work will be completed during the next several months. Some interesting patterns emerge from the preliminary results, however. The two plots between 500 m and 600 m elevation at Bilsa have about 100 tree species ³ 10 cm DBH, a typical value for lowland wet forest in Ecuador. Alpha diversity of trees in the region is lower than in the upper Amazon basin of eastern Ecuador and Peru, where one-hectare plots typically have 200-250 tree species ³ 10 cm DBH. The higher plot at Bilsa, Plot 2 at 700 m elevation, has only an estimated 37 species, a very low figure for forests in Ecuador below 1500 m. Two species, the stilt-root palm Socratea exorrhiza and the Lecythidaceae tree Eschweilera caudiculata, are by far the most abundant trees in Plot 2. We do not yet have an explanation, or even a reasonable hypothesis, for the unusually low diversity at that plot.
Conservation of Biodiversity and Natural Communities in the Region
We hope that the results of our botanical studies in the Mache-Chindul mountain region will serve to help the conservation efforts being carried out by various organizations, including the Ecuador Ministry of Environment which is responsible for protection and administration of the Mache-Chindul Ecological Reserve, the Jatun Sacha Foundation which adminsters the Bilsa Biological Station, and the Tercer Mundo Foundation which is resonsible for the Cerro Pata de Pájaro Protection Forest.
Our information on plant species distriibutions will be incorporated into Ecuador’s National Biodiversity Database which is adminstered by the Ministry of Enviroment. We do plan to continue field studies in the region, particularly in northern Manabí province, and to work actively with the Tercer Mundo Foundation to help the Foundation assist local landowners who wish to establish legal recognition of their privately owned tracts as "Protection Forests" registered with the Ministry of the Environment. Technical reports on flora, fauna and other characteristics are required in the registration process, and we have agreed to help write the reports on behalf of the Tercer Mundo Foundation and the landowners who wish to protect their forests.
We would like to thank the various institutions and individuals in Ecuador who helped us in different ways to carry out this project. The Jatun Sacha Foundation provided logistical support and lodging at the Bilsa Biological Station. The founder and director of the Bilsa station, Michael McColm, encouraged the project and station administrator Carlos Aulestia helped in numerous ways, as did Peace Corps volunteer Cyrus Brame.
The Tercer Mundo Foundation provided help to our field studies at Cerro Pata de Pájaro and other areas in northern Manabí province, We thank especially Rosario Castillo, director of the foundation in Pedernales, and extensionist Carlos Robles, who guided us daily on our field excursions in the region.
The technical staff of the National Herbarium of Ecuador in Quito, especially Mercedes Asanza and Ximena Aguirre, helped with logistical matters and the processing of specimens. Likewise, at Missouri Botanical Garden, Mary Todd assisted with specimen processing.
We also thank the Ecuador Conservation Data Center for permission to reproduce the vegetation map of the Mache-Chindul region which is included with this report.
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Dodson, C. H., A. H. Gentry & F. M. Valverde. 1985. La Flora de Jauneche: Los Ríos, Ecuador. Flórulas de las Zonas de Vida del Ecuador 1–512. Banco Central del Ecuador, Quito.
Dodson, C. H. & A. H. Gentry. 1991. Biological extinction in western Ecuador. Annals of Missouri Botanical Garden 78: 273–295.
Little, E. L., Jr. & R. G. Dixon. 1969. Arboles Comunes de la Provincia de Esmeraldas, Ecuador. United Nations Development Program, and Food and Agriculture Organization, Rome.
Neill, D. A. 1997. Ecuadorian Pacific coast mesic forests. Pp. 508–518. In: WWF and IUCN. Centers of Plant Diversity—A Guide and Strategy for their Conservation. Volume 3: The Americas. IUCN, Cambridge.
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