Island Of Saba Research Articles

Spatial distribution of settlement of Diadema antillarum around Saba, Dutch Caribbean.

The mass mortality event of the herbivorous sea urchin Diadema antillarum in 1983-1984 has been a major contributor to the diminished resilience of coral reefs throughout the Caribbean. The reduction in grazing pressure resulted in algae proliferation, which inhibited coral recruitment after disturbances such as disease, hurricanes, pollution and climatic change induced marine heat waves. Natural recovery of D. antillarum after the 1983-1984 die-off has been slow. However, the few locations with recovered populations exhibit signs of improvement in coral reef health, prompting interest in D. antillarum restoration. Current restoration strategies include translocation of wild individuals, the restocking of juveniles that are either cultured from gametes or collected as settlers and head-started in a nursery, and assisted natural recovery by providing suitable settlement substrate. Both the collection of wild settlers and assisted natural recovery necessitate an understanding of the local, spatiotemporal trends in settlement. In this study, which was carried out on the Dutch Caribbean Island of Saba, artificial turf settlement collectors were deployed at nine locations around the island and monitored from June 2019 till July 2020 (13 months). The primary objective was to identify trends in larval settlement in space and time, to be able to optimize restoration efforts. Additionally, the small size of Saba allowed us to deploy settlement collectors around the island and compare D. antillarum settlement between windward and leeward sides. Our study showed that on Saba, D. antillarum settlement peaked in June and July, following similar seasonal trends observed around other islands in the Northeastern Caribbean. By far the most settlement occurred at the leeward side of the island, suggesting that hydrodynamic forces entrained D. antillarum larvae in the lee of Saba and/or calmer waters facilitated settlement. Limited settlement occurred on the more exposed windward locations. The identified high settlement locations are candidates for settler collection and restoration attempts. Continued monitoring of D. antillarum settlement, especially in light of the 2022 D. antillarum die-off, holds significance as it can provide insights into the potential of natural recovery.

The complete mitochondrial genome of the Critically Endangered Saba Green Iguana, Iguana iguana (Squamata: Iguanidae)

The populations of native iguanas in the Caribbean Lesser Antilles are threatened by the wide occurrence and spread of non-native iguanas. Until recently, competitive hybridization was not believed to threaten the Saba Green Iguana, a subpopulation of Iguana iguana (Linnaeus, 1758) from the island of Saba. However, the arrival of non-native iguanas has put the native population at risk, leading to a change in the conservation status of the Saba Green Iguana to Critically Endangered, according to guidelines from the International Union for the Conservation of Nature. Here, we generated the complete mitogenome of the Saba Green Iguana using Oxford Nanopore long-read technology. The mitogenome is 16,626 bp long and has 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and a control region (1194 bp). Noteworthy, this is only the second published mitogenome for the Iguana iguana species complex, despite the known high intraspecific genetic variation.

Assisted Natural Recovery: A Novel Approach to Enhance Diadema antillarum Recruitment

The massive die-off of the sea urchin Diadema antillarum in 1983–1984 is one the main reasons for low coral recruitment and little coral recovery in the Caribbean. As the natural recovery of D. antillarum is slow to non-existent, multiple restoration studies have been attempted. There are currently three different approaches to obtain individuals for restocking: the translocation of wild-collected juveniles or adults, lab-reared juveniles cultured from wild-collected settlers, or lab-reared juveniles cultured from gametes. All three methods are costly and can only be applied on a relatively small scale. We here propose a fourth, new, approach, which we term assisted natural recovery (ANR) of D. antillarum populations. ANR, a concept already applied in terrestrial restoration to restore forests and grasslands, can accelerate succession by removing barriers to natural recovery. In this study, performed on the Dutch Caribbean island of Saba, suitable settlement substrate was provided in the form of bio ball streamers that were attached to the reef shortly before the settlement season. At the end of the experiment, reefs with streamers had significantly higher D. antillarum recruit densities than control reefs without additional settlement substrate, indicating that the lack of settlement substrate is an important factor constraining natural recovery. However, D. antillarum recruit abundance was low compared to the measured settlement rates, possibly due to low post-settlement survival. The size distribution of recruits showed that recruits almost never became larger than 20 mm, which is likely due to predation. We conclude that, next to low settlement availability, low post-settlement survival and high predation on recruits also constrain the natural recovery of D. antillarum populations on Saba. To improve the survival of settlers till adults, we propose to 1) reduce predation on settlers by using bio balls or other substrates that can provide shelter to larger individuals and 2) optimize the reef habitat by removing macroalgae, either manually or by facilitating other herbivores. To improve the survival of recruits, we suggest to 1) choose sites with a known lower predation density or 2) protect recruits with a corral around the reef underneath the streamers. The combination of these measures could improve prospects for ANR, and we expect this new approach can contribute to the recovery of D. antillarum populations in the future.

The zombie pirate invasion: an introduction to immunology concepts.

Abstract Introduction The terminology that is used to describe the parts of the immune system can be very intimidating to student learners. We have noticed that some students disengage from the learning process early on in the semester because they are overwhelmed by “jargon” (e.g. CD markers, cytokines). The classroom exercise described here serves to introduce students to the concept of immunology as the body’s defense system as well as to provide a simplified framework for students to refer to as they learn more advanced concepts. Methods First-year medical students at Saba University School of Medicine, located on the small Dutch Caribbean island of Saba, are engaged in this group-based exercise at the beginning of the immunology content block. We present them with the following scenario: “Our island is being invaded by zombie pirates! How can we defend against this attack?” Each learning group is assigned a specific task, such as figuring out how to communicate across the island, determining how to differentiate zombies from residents, or planning how to train the populace in defense. Students then share their answers with the class. Instructors facilitate the linking of student answers with applicable concepts in immunology, e.g. communication = cytokine signaling, zombie identification = MHC presentation, training centers = lymph nodes. Results/Conclusion We have found that students remember this discussion in the following weeks, and that we can use the ideas they presented as a framework for reference as we introduce immunology concepts. This activity could be adapted to a number of different educational settings, contingent on the unique geographic or structural features of the campus on which other students study.

Assessing the preservation of biogenic strontium isotope ratios (87 Sr/86 Sr) in the pars petrosa ossis temporalis of unburnt human skeletal remains: A case study from Saba.

RationaleStrontium isotope (87Sr/86Sr) analysis of skeletal remains has become a powerful tool in archaeological studies of human migration and mobility. Owing to its resistance to post‐mortem alteration, dental enamel is the preferred sampling material used for 87Sr/86Sr analysis in bioarchaeological provenance research, although recent studies have demonstrated that cremated bone is also generally resistant to diagenesis. This paper presents the results of a pilot study exploring the potential of unburnt petrous bone (pars petrosa) as a reservoir of biogenic (diagenetically unaltered) strontium, as the otic capsule or bony labyrinth within the petrous bone is extremely dense and is thought to be unable to remodel after early childhood, potentially providing an alternative for dental enamel.MethodsFrom an individual from a colonial‐era (18th century) site on the island of Saba in the Caribbean for whom previous enamel 87Sr/86Sr results had indicated non‐local origins, multiple locations (n = 4) on the petrous were sampled and measured for strontium isotope composition. Saba (13 km2) has been extensively mapped for baseline strontium isotopes (n = 50) with 87Sr/86Sr varying from ca 0.7065 to 0.7090, whereas enamel 87Sr/86Sr (n = 3) ranged from 0.7104 to 0.7112.ResultsAll four petrous 87Sr/86Sr ratios (0.7111–0.7122) are consistently and considerably higher than the local bioavailable range, and very similar to the enamel 87Sr/86Sr. These results provide initial evidence that unburnt petrous bones may preserve biogenic strontium, at least in this specific burial context.ConclusionsWhile more research in diverse burial conditions is needed to validate this observation, if confirmed, it would have broader implications for sample selection strategies in bioarchaeological studies using the strontium isotope method.

Establishment of two nonnative parthenogenetic reptiles on Saba, Dutch Caribbean: Gymnophthalmus underwoodi and Indotyphlops braminus

The native herpetofauna of the Lesser Antillean island of Saba (13 km2; 17.63°N, -63.24°W) includes one snake, Alsophis rufiventris, and four species of lizards, Anolis sabanus, Iguana melanoderma, Sphaerodactylus sabanus, and Thecadatylus rapicauda (Powell et al. 2015). Here, we report the establishment of both Gymnophthalmus underwoodi Grant, 1958 and Indotyphlops braminus (Daudin, 1803) on the island.

A preliminary survey of the inland aquatic macroinvertebrate biodiversity of St. Thomas, US Virgin Islands

ABSTRACT The use of quantitative invertebrate community indices to monitor inland water quality is widespread. However, this approach is rare for the Caribbean, where the dominant animal groups are substantially different from those in continental waters and surface water availability is strongly influenced by seasonality. For the United States Virgin Islands, these limitations are amplified by a general lack of biodiversity data on non-marine aquatic environments. To begin bridging this knowledge gap, we surveyed 41 inland aquatic sites on the island of St. Thomas and adjacent Water Island and Saba Island. Samples were obtained from lotic and lentic habitats, phytotelmata, rural and urban areas, and natural and anthropogenic settings. Out of 118 taxa across 591 records, 46% were first records for the islands sampled, with 23.4% of these being new to the US Virgin Islands territory. Shrimps and snails dominated lotic environments taxonomically, whereas insects dominated lentic environments and phytotelmata. Two confirmed undescribed species were encountered, but this is likely underestimated given the large number of juveniles encountered for some insect groups and the need for a taxonomic revision of multiple genera. The most common and widespread species was the invasive snail Melanoides tuberculata. When sampling periods or multiple samples from the same site were compared, only a 36–42% similarity was found, suggesting a much higher biodiversity than currently appreciated for these seasonally fluctuating habitats. Deep knowledge of inland aquatic biodiversity is necessary to establish baselines to assess watershed health and develop management and conservation plans in the US Virgin Islands, which in turn may be applied to other Caribbean islands.

Complete mitogenome sequences of Aedes (Howardina) busckii and Aedes (Ochlerotatus) taeniorhynchus from the Caribbean Island of Saba

We report the complete mitogenome (Mt) sequences of Aedes (Howardina) busckii and Aedes (Ochlerotatus) taeniorhynchus. The sequences were extracted from one individual per species from the Dutch Leeward Island of Saba. The length of the Ae. busckii Mt was 16,794 bp with 80.6% AT content. The Ae. taeniorhynchus Mt was 16,216 bp long with 79.8% AT content. These are the first full Mt sequences available for these species.

Saba, de onbedorven koningin van de Antillen

Saba, the unspoiled Queen of the Antilles The isolated Caribbean island of Saba is affectionately called ‘the unspoiled Queen’, due to the unaffected character of its natural environment. European colonists from Zeeland (The Netherlands) and the British Isles occupied the island four centuries ago and partially changed it into a cultural landscape with an outstanding character and a vernacular architecture that is worth to be well protected. The inhabitants – still no more than 2000 – had to adjust to the rugged and mountainous landscape. This is expressed by the location of the villages, the network of paths and stairs connecting them, the construction and size of the wooden cottages and the cisterns and burial sites on their properties. This combination makes Saba unique in the Caribbean region. The Saban architecture which is rooted in a Victorian-British building tradition, has hardly changed over the years, though building in concrete is a serious threat nowadays.

Using participatory action research to operationalize critical systems thinking in social-ecological systems

Eelderink, M., J. M. Vervoort, and F. van Laerhoven. 2020. Using participatory action research to operationalize critical systems thinking in social-ecological systems. Ecology and Society 25(1):16. https://doi.org/10.5751/ES-11369-250116

Cist graves on Saba: funerary traditions in the colonial Caribbean

Abstract

New avifaunal records and checklist for the island of Saba, Caribbean Netherlands

New avifaunal records and checklist for the island of Saba, Caribbean Netherlands

In-situ incubation of a coral patch for community-scale assessment of metabolic and chemical processes on a reef slope.

Anthropogenic pressures threaten the health of coral reefs globally. Some of these pressures directly affect coral functioning, while others are indirect, for example by promoting the capacity of bioeroders to dissolve coral aragonite. To assess the coral reef status, it is necessary to validate community-scale measurements of metabolic and geochemical processes in the field, by determining fluxes from enclosed coral reef patches. Here, we investigate diurnal trends of carbonate chemistry, dissolved organic carbon, oxygen, and nutrients on a 20 m deep coral reef patch offshore from the island of Saba, Dutch Caribbean by means of tent incubations. The obtained trends are related to benthic carbon fluxes by quantifying net community calcification (NCC) and net community production (NCP). The relatively strong currents and swell-induced near-bottom surge at this location caused minor seawater exchange between the incubated reef and ambient water. Employing a compensating interpretive model, the exchange is used to our advantage as it maintains reasonably ventilated conditions, which conceivably prevents metabolic arrest during incubation periods of multiple hours. No diurnal trends in carbonate chemistry were detected and all net diurnal rates of production were strongly skewed towards respiration suggesting net heterotrophy in all incubations. The NCC inferred from our incubations ranges from −0.2 to 1.4 mmol CaCO3 m−2 h−1 (−0.2 to 1.2 kg CaCO3 m−2 year−1) and NCP varies from −9 to −21.7 mmol m−2 h−1 (net respiration). When comparing to the consensus-based ReefBudget approach, the estimated NCC rate for the incubated full planar area (0.36 kg CaCO3 m−2 year−1) was lower, but still within range of the different NCC inferred from our incubations. Field trials indicate that the tent-based incubation as presented here, coupled with an appropriate interpretive model, is an effective tool to investigate, in situ, the state of coral reef patches even when located in a relatively hydrodynamic environment.

From Hell’s Gate to the Promised Land: Perspectives on Poverty in Saba, Dutch Caribbean, 1780 to the Mid-Twentieth Century

Archaeological research concerning poverty has expanded during the 21st century. Finding poverty in material things has become a challenge, and, consequently, research has been reoriented to understanding the social processes that produce and sustain poverty. Poverty is understood differently according to class and experienced differently according to scale, locality, race, and gender. By taking a whole-society approach to the small island of Saba, Dutch Caribbean, the materiality of Saba’s classes can be made visible if the social processes behind them can be revealed. Designating groups, individuals, and landscapes as “poor,” however, homogenizes these material vectors for projecting class. This gives poverty an ephemeral nature relative to those designating poverty to people and spaces. Therefore, poverty is best understood reflexively through powered perspectives and powered landscapes, rather than through a static pile of representative material objects.

The Life History of an Enslaved African: Multiple Isotope Evidence for Forced Childhood Migration from Africa to the Caribbean and Associated Dietary Change

Archaeological excavations of an enslaved African domestic area at the Spring Bay Flat plantation on the island of Saba, Dutch Caribbean, uncovered a small concentration of artefacts (shell, metal nails, animal bones and five human teeth) overlaid with a lock hinge, interpreted as a lockbox and its contents. Dental anthropological and multi‐isotope (strontium, oxygen, carbon and nitrogen) analyses of the teeth revealed that they belonged to a single individual who originated from Africa and survived a period of pronounced nutritional stress as a juvenile. The results provide rare insights into the life history of an individual who probably experienced enslavement, (forced) migration from Africa and adaptation to plantation life in the colonial‐era Caribbean.

Population Genetic Structure, Abundance, and Health Status of Two Dominant Benthic Species in the Saba Bank National Park, Caribbean Netherlands: Montastraea cavernosa and Xestospongia muta.

Saba Bank, a submerged atoll in the Caribbean Sea with an area of 2,200 km2, has attained international conservation status due to the rich diversity of species that reside on the bank. In order to assess the role of Saba Bank as a potential reservoir of diversity for the surrounding reefs, we examined the population genetic structure, abundance and health status of two prominent benthic species, the coral Montastraea cavernosa and the sponge Xestospongia muta. Sequence data were collected from 34 colonies of M. cavernosa (nDNA ITS1-5.8S-ITS2; 892 bp) and 68 X. muta sponges (mtDNA I3-M11 partition of COI; 544 bp) on Saba Bank and around Saba Island, and compared with published data across the wider Caribbean. Our data indicate that there is genetic connectivity between populations on Saba Bank and the nearby Saba Island as well as multiple locations in the wider Caribbean, ranging in distance from 100s–1000s km. The genetic diversity of Saba Bank populations of M. cavernosa (π = 0.055) and X. muta (π = 0.0010) was comparable to those in other regions in the western Atlantic. Densities and health status were determined along 11 transects of 50 m2 along the south-eastern rim of Saba Bank. The densities of M. cavernosa (0.27 ind. m-2, 95% CI: 0.12–0.52) were average, while the densities of X. muta (0.09 ind. m-2, 95% CI: 0.02–0.32) were generally higher with respect to other Caribbean locations. No disease or bleaching was present in any of the specimens of the coral M. cavernosa, however, we did observe partial tissue loss (77.9% of samples) as well as overgrowth (48.1%), predominantly by cyanobacteria. In contrast, the majority of observed X. muta (83.5%) showed signs of presumed bleaching. The combined results of apparent gene flow among populations on Saba Bank and surrounding reefs, the high abundance and unique genetic diversity, indicate that Saba Bank could function as an important buffer for the region. Either as a natural source of larvae to replenish genetic diversity or as a storehouse of diversity that can be utilized if needed for restoration practices.

Remotely Local: Ego-networks of Late Pre-colonial (AD 1000–1450) Saba, North-eastern Caribbean

Ego-networks, based on a socio-metric method for the analysis of the direct social relations an individual engages in, of archaeological site assemblages may be used to great effect in archaeology. They provide a means to combine multi-scalar and multi-disciplinary data and thereby explore sites as a nexus of material relations. This paper outlines how such a site ego-network could be constructed. This is illustrated using the fourteenth century site of Kelbey’s Ridge 2, Saba, in the North-eastern Caribbean. Kelbey’s Ridge 2 is an interesting case study since it was likely a newly established, but also short-lived settlement. The reason for settlement may have been that, even if the island of Saba was relatively poor in terrestrial resources, it had a geographically strategic location and access to rich marine resources. Intra-site features at the site evidence a complex set of relations between house spaces and living and deceased members of the community. Additionally, the site’s engagement with the wider island world is reflective of a transitional moment for communities in the late pre-colonial North-eastern Caribbean. A betweenness analysis of its ego-network provides a new perspective of Kelbey’s Ridge 2, pinpointing material practices and objects that must have been crucial for the viability and identity of the community. This case study shows that ego-networks may be profitably used alongside current archaeological relational theories, substantive studies of site assemblages and other archaeological network approaches.

Putting Saban English on the map

Small Caribbean islands offer a unique venue for examining principles of language contact and sociolinguistic variation. Only recently, however, has the use of acoustics-based analysis been incorporated as a tool for the phonological description and analysis of Caribbean varieties. This study offers the first empirical description and analysis of the English spoken on the island of Saba, a Dutch municipality located in the Eastern Caribbean. Data come from 22 sociolinguistic interviews with long-term residents conducted on Saba in 2012. Phonological and morphosyntactic features are analyzed with respect to the interrelationship between effects from community, ethnicity, and generation. Overall, this study contributes to the important process of phonological and morphosyntactic documentation of lesser-known Caribbean varieties, highlighting the usefulness of acoustics-based and statistical analyses in such processes.

Water Use at Palmetto Point and Middle Island, Saba, Dutch Caribbean: A Modeled Approach for Settlement Viability

The neighboring abandoned villages of Palmetto Point and Middle Island, on the northwest of Saba, Dutch Caribbean, relied upon rainwater caught in cisterns as their primary source of potable water. The island of Saba is located in the northern Lesser Antilles, and thus is subject to a rainy and dry season in the course of a year. Using measurements of the village cisterns and their respective catchments combined with variations in monthly rainfall data over the course of a year, a study of water replenishment versus water consumption is possible for Palmetto Point and Middle Island. As a result, fluctuations in population in villages with measurable, finite supplies of potable water allow a researcher to determine the viability of the villages at particular points in time, and the resultant effects on internal economies and social dynamics during these periods.

Reef Fishes of Saba Bank, Netherlands Antilles: Assemblage Structure across a Gradient of Habitat Types

Saba Bank is a 2,200 km2 submerged carbonate platform in the northeastern Caribbean Sea off Saba Island, Netherlands Antilles. The presence of reef-like geomorphic features and significant shelf edge coral development on Saba Bank have led to the conclusion that it is an actively growing, though wholly submerged, coral reef atoll. However, little information exists on the composition of benthic communities or associated reef fish assemblages of Saba Bank. We selected a 40 km2 area of the bank for an exploratory study. Habitat and reef fish assemblages were investigated in five shallow-water benthic habitat types that form a gradient from Saba Bank shelf edge to lagoon. Significant coral cover was restricted to fore reef habitat (average cover 11.5%) and outer reef flat habitat (2.4%) and declined to near zero in habitats of the central lagoon zone. Macroalgae dominated benthic cover in all habitats (average cover: 32.5 – 48.1%) but dominant algal genera differed among habitats. A total of 97 fish species were recorded. The composition of Saba Bank fish assemblages differed among habitat types. Highest fish density and diversity occurred in the outer reef flat, fore reef and inner reef flat habitats. Biomass estimates for commercially valued species in the reef zone (fore reef and reef flat habitats) ranged between 52 and 83 g/m2. The composition of Saba Bank fish assemblages reflects the absence of important nursery habitats, as well as the effects of past fishing. The relatively high abundance of large predatory fish (i.e. groupers and sharks), which is generally considered an indicator of good ecosystem health for tropical reef systems, shows that an intact trophic network is still present on Saba Bank.