Saba

Trail maps of Saba 2016 (GIS)

source : Saba Conservation Foundation

Saba is a five square mile island with about 1200 permanent inhabitants located off the coast of St. Maarten in the Netherlands Antilles (go to map from link in banner). English is the official language of the island but Dutch is also taught in schools and is spoken by many Sabans.

In February 2006, Conservation International, in conjunction with the Saba Conservation Foundation, embarked on a project to survey the biodiversity of Saba from beneath the sea to the summit of its highest peak, Mt. Scenery. As part of this effort, the Department of Botany of the Smithsonian Institution surveyed the marine algae.

In 2006 and 2007, The New York Botanical Garden participated in surveying the bryophytes, lichens, and vascular plants of the island. Although small in size, Saba's rugged topography is covered by several vegetation types, ranging from near desert to cloud forest. Our goal is to provide illustrated checklists (a virtual museum) of all of the plants and lichens that grow on Saba and in the surrounding sea. Both native and introduced plants are included.

To find collections representing species of flowering plants, gymnosperms, ferns, bryophytes, marine algae, or lichens, you can access the information available for a given group by clicking on the appropriate image on the left hand side of this page.

It is forbidden to pick plants and to remove plants from the island of Saba. All natural history studies must first be approved by the government of Saba. To find out how to obtain permission to collect herbarium specimens as was done in this study contact the Saba Conservation Foundation.

All photographs are copyrighted by the photographer. Most of the photographs of the flowering plants, gymnosperms, ferns, bryophytes, and lichens were taken by Carol Gracie and most of those of the marine algae were taken by Diane Littler. Harrie Sipman took the photo micrographs of the lichens. For permission to use the images, contact the photographers. Citizens of Saba have permission to download images from the website for personal or educational purposes.

Abstract
Surveying subaqueous beach profiles and features beyond wading depths can be a costly process, requiring use of expensive equipment and boats. This paper describes the materials and methods of a simple, low-cost technique for underwater bathymetric surveying, herein named the diver depth-gauge profiling (DDGP) method. Although accuracy of depth data depends on the quality of the depth gauges used, it is commonly within 0.3 m. Data collection reliability was evaluated by repeated underwater beach profile surveys, and an example of its use in the Caribbean is provided. 

Since the publication of a checklist of Lesser Antilles’ orchids not far of twenty years ago, the orchid family has been the subject of many studies and publications, including extensive taxonomic revisions, thanks to the use of molecular tools and to the improvement of data availability through Internet (virtual herbariums on line). The knowledge of his family and on its distribution has been largely improved. The analysis of these new data and of in situ intensive prospections has given a number of 138 species recorded in the Lesser Antilles (in March 2012), 130 of them being native. This apparently stable number compared to the 1993’s checklist comes from the suppression of some species and the addition of others. It is also a consequence of taxonomic changes for around one third of the taxa. Guadeloupe remains the richest island with 103 recorded species, followed by Dominica, with 90 species and Martinique with 80 species. Examination of all the types specimen on one island’s endemics does not support the endemism level sometimes described. There are only 5 true one-island endemic species, 3 to Guadeloupe (Basse Terre), one to Dominica and one to Montserrat. The rate of endemism in the Lesser Antilles is 16%, and 27% of the Lesser Antillean orchids are endemics to the West Indies.

Bijzondere uitgave van ‘Orchideeën’, tweemaandelijks tijdschrift van de Nederlandse Orchideeën Vereniging, met een special over Saba. Michiel Boeken, voor deze gelegenheid gastredacteur, woonde en werkte twee jaar lang op Saba en maakte onder andere een inventarisatie van de orchideeën die er voorkomen. Dat zijn er meer dan twintig, en dat is veel voor een eilandje van amper vier kilometer in doorsnede. Hoe valt die soortenrijkdom te verklaren? En wanneer bloeien de meeste orchideeën? Na een inleiding over Saba volgt een uitgebreid geannoteerde lijst van orchideeensoorten per vegetatiezone waar zij voorkomen, van de kliffen en droge bossen tot het regenwoud en het nevelwoud, plus de op het eiland voorkomende exotische orchideeen en niet waargenomen, maar mogelijk wel op het eiland voorkomende soorten. Alle soorten zijn geillustreerd met fraaie foto's van de auteur.

Short case study prepared for the CANARI Workshop on Revenue Generation for Protected Areas, Saba, Netherlands Antilles, June 5-9, 1995. The Saba Marine Park (SMP) was created in 1987. Prior the establishment of SMP few divers visited Saba. Dive operators at the time estimated the number of divers at 500 in 1984 and 1,000 in 1986. Following the establishment of SMP the number of visiting divers and snorkellers increased rapidly: from 2,600 in 1988 to well over 5,000 in 1994. Despite the fact that Saba is not among the popular yachting destinations in the northeastern Caribbean, the increase of yachts visiting SMP proved to be even more dramatic. In order to become self-financing, SMP embarked on a three-pronged revenue generation strategy: visitor/user fees, souvenir sales, and donations. One may conclude from the 1994 and 1995 budgets that the Saba Marine Park has achieved its goal to become a self-financing entity within the Saba Conservation Foundation. A number of important lessons which will have applications elsewhere have been derived.

Abstract:

Saba is the smallest of the three Windward Islands in the Netherlands Antilles, with an area of 13 km2. Saba is the northernmost island within the Lesser Antilles' inner curve. The island is actually the top of a dormant volcano. Typical of the island are the steep cliffs, deep ravines running radially and sheer cliff coasts. The highest top is the Mt. Scenery, commonly called “The Mountain”. About 1200 people live on Saba in four villages all situated on the south- eastern half of the island. The northwestern half is not inhabited. Only a small part of the land area is used for agriculture or cattle breeding. In the south there is a stone crusher facility.

The climate is tropical and according to the system of Köppen it falls between a savanna- and monsoon climate, however the big differences in altitude cause a large variety of climatologi- cal conditions. Above 450 meters the rainfall and humidity gradually increase until they reach their maximum on the top of The Mountain. The top of The Mountain is nearly always veiled in clouds. The diversity of plants and plant-communities is caused by these variations in climatological conditions.

With 520 species the small island of Saba possesses practically the same number of species of wild plants as the much larger island of St. Maarten. The number of ferns is especially large. Saba has no island-endemic species among the plants. However, the geographical distribution of six species and one variety is limited to only a few islands, and 4.6% of the species is en- demic to the Lesser Antilles and the Virgin Islands. The Bryophyte flora consists of 48 leaf mosses and 31 liverwort species.

Expressing the differences in climatological conditions as the altitude increases, a series of plant communities are found, ranging from Croton thickets to (secondary) rainforest and elfin woodland. The elfin woodland is of a regionally rare type. The palm brakes and the ravine rainforest are practically undisturbed by human activities. They belong to the few virgin vegetations of the Netherlands Antilles. The tree-fern brakes are a special type of secondary vegetation, which develops under conditions of high humidity. The secondary rainforest zone was seriously disturbed in the past. There are still small cultivation plots here. Wherever the vegetation is left alone however, new rainforest is developing. The rainforest is one of the most species-rich plant communities. This is also where the greatest number of leaf mosses are found on Saba. The evergreen and seasonal formation zones were also disturbed in the past, however the vegetation is recovering. The great variety of forest formations on The Mountain makes this area highly attractive to visitors. The uninhabited area in the northwest of the island is important to the survival of various small island populations and has a high scenic value.

Saba's fauna has very few species compared to a similar area on the mainland, but this is to be expected from a relatively isolated small island.
Among the vertebrates the birds form the largest group, represented by 26 local and breeding species. In addition 36 migrating species are present every year on a temporary basis. Amphibians and reptiles are the next largest group of vertebrates with eleven species.

Bats are the only mammals on Saba that were not introduced by humans. This group is represented by five species. There is one island endemic among the vertebrates: the lizard Anolis sabanus. One species, the Red-bellied Racer Alsophis rufiventris is limited to Saba and St. Eustatius and is listed on the “Red List of Threatened Animals” of the IUCN. Various vertebrates are endemic to the Lesser Antilles and the Virgin Islands, either at the species level or the subspecies level: two bats, nine birds, one amphibian and one reptile. The gecko Sphaerodactylus sabanus, the bat sub-species Natalus stramineus stramineus and the Trembler Cinclocerthia ruficauda pavida have a geographical range, which is limited to only a few islands. Among the birds and reptiles there are species of which the population has declined because of hunting or the gathering of the eggs, like for instance the Rednecked Pigeon Columba squamosa, the Audubon's Shearwater Puffinus lherminieri, and the green Iguana Iguana iguana. A few bird species are regionally almost completely limited to the habitat of the rainforest and the mountain formations, e.g. the Purple-throated Carib Eulampis jugularis, the Trembler Cinclocerthia ruficauda pavida and the Blue-crowned Euphonia Euphonia musica flavifrons, which has not been seen since 1952. The possibly endangered Bridled Quail-dove Geotrygon mystacea and Red-billed Tropicbird Phaeton aetherius mesonauta breed on Saba. Of the latter the breeding population on Saba is the largest of the Caribbean region. Of the invertebrates not much more is known than 86 names. The Mountain Crab Gecarcinus ruricola is endangered through hunting.

In the past the nature of Saba was mainly impacted by activities related to agriculture and cattle breeding. Today, the most important threats are destruction and degradation of habitat by development in general, especially because of the lack of regulations.
Since the nineteenfifties there is a lot of interest in the conservation of nature and the beautiful scenery. The necessity to preserve the top of The Mountain is mentioned many times, accompanied by specific plans. A group of people even promoted the idea to declare the whole island of Saba a conservation park. Up until today however, the terrestrial nature on the island remains unprotected.

Several studies have produced a wealth of data, yet not enough for optimum nature conservation. Further vegetation research of the top of The Mountain and the northern part of the island is necessary, as well as further study of the status of the island populations of regionally rare and/or endangered species. Also additional knowledge of the invertebrates is needed.

For now a few general conclusions can be drawn with respect to conservation of the biodiversity. For this conservation it is necessary to secure large contiguous areas. For small islands this can be problematic, but there are still a lot of possibilities on Saba. In particular the uninhabited northwestern part of the island and The Mountain above 450 meters would qualify. Specific conservation is required for the breeding places of the Audubon's Shearwater, Tropicbirds and other seabirds on Green Island and Diamond Rock. 

Data presented herein provide records of four species of bats new to the fauna of the Antillean island of Saba — Monophyllus plethodon, Ardops nichollsi, Tadarida brasiliensis, and Molossus molossus. Together with three species previously recorded from the island – Brachyphylla cavernarum, Artibeus jamaicensis, and Natalus stramineus – the chiropteran fauna of the island is documented to be composed of seven species. Our analysis of species/area relationships for West Indian bats provides a slope value of z = 0.177 and R2 = 0.76; therefore, the bat fauna of the West Indies has the flattest slope for this relationship of any West Indian group. This relationship is best explained by a propensity for over water dispersal by West Indian bats. We propose to unite the chiropteran faunas of the islands of Anguilla, Antigua, Barbuda, Nevis, Saba, St. Barthélemy, St. Eustatius, St. Kitts, and St. Martin by recognizing them as the Northern Antillean Faunal Area. Given the small size of Saba (12 km2) and the even smaller effective habitat for non-molossid bats (4 km2), conservation concerns are expressed for the future of the fauna and some recommendations are made for its preservation.