Curacao

ABSTRACT

A major challenge in invasion ecology is determining which introduced species pose a threat to resident species through competitive displacement. Here, we provide a statistical framework rooted in coexistence theory to calculate coexistence outcomes – including competitive displacement – between resident and invading species. Advantageously, our framework uses readily available trait and abundance data rather than the demographic data traditionally used in coexistence theory applications which is often difficult to collect for most species. Our framework provides methods for predicting displacement that has yet to manifest in incipient invasions, and for quantifying displacement in ongoing invasions. We apply this framework to the native and introduced gecko species on Curaçao and predict the displacement of all three native species by introduced species and quantify that the displacement of one native species is already underway. Our results affirm that trait and abundance data are suitable proxies to reasonably predict and quantify coexistence outcomes. 

Abstract

It is becoming increasingly clear that Caribbean islands are very vulnerable to the effects of climate change, such as sea level rise, longer periods of droughts, loss of biodiversity, more extreme weather events (flooding and hurricanes), and increased freshwater demands. Addressing these issues encourages good climate change adaptation governance. So far, however, the literature has not discussed what good governance could mean in this context. The aim of this paper is, therefore, to address this knowledge gap by developing an assessment framework and showing its usefulness. The framework is based on a review of the literature and is applied in an assessment of adaptation practices in Curaçao. The assessment is based on a review of Curaçao policy documents and in-depth interviews with key stakeholders. We found that the developed framework was useful for obtaining a better insight into the quality of adaptation governance on Caribbean islands, and that in the Curaçao practices, the good governance principles of transparency and inclusiveness are better elaborated in comparison to connectivity, accountability and government effectiveness. We conclude the paper with some reflections on the potential of the framework and some suggestions for further research.

Abstract

Red-billed Tropicbirds have historically been considered rare visitors to the waters around the islands of Aruba, Curaçao, and Bonaire in the southern Caribbean. However, in recent years there has been an increase in documented records. We summarize all known Red-billed Tropicbird records for the region and review broader regional population and movement data to place this increase in records in context. We recommend continued careful documentation of Red-billed Tropicbird records on and around the islands of Aruba, Curaçao, and Bonaire and the implementation of a standardized monitoring pro-gram across the Caribbean range for the species to better understand the species' population status, trends, and breeding and at-sea distribution

Abstract

Coral reefs are one of the most biodiverse yet threatened ecosystems on the planet. Our understanding of what contributes to a coral reef’s resilience to adapt to global and local threats is not well established. Thriving reefs in close proximity to anthropogenic impacts indicate there are opportunities for improved understanding of the underlying factors that influence the ability of some coral species to withstand environmental stressors and changing oceanographic conditions. Research suggests that resource availability and a coral’s trophic strategy can improve a coral’s tolerance to environmental stressors. Such discoveries have already been made, but the effects of resource availability on heterotrophic coral species have been minimally explored in the Caribbean; a region that has suffered substantial declines in coral health and cover–. Regardless of these declines, Curaçao, an island in the Southern Caribbean, possesses uncharacteristic coral diversity and cover for the region. One of the most abundant species covering the Curaçao reef tract, Madracis mirabilis, is largely heterotrophic in its feeding strategy. The growth and distribution of this species was tracked across 7 sites spanning approximately 40 kilometers along natural and anthropogenic gradients of nutrients in Curaçao. Our findings suggest that the highest growth and percent cover of M, mirabilis, can be found in regions with the highest exposure to anthropogenic nutrient loading. These data provide insights into how some corals may be better adapted to changing environmental conditions and degradations in water quality

Abstract
Tropical dry forests experience pronounced seasonal changes in precipitation mani- 
fested in varied plant phenologies. At landscape scales, geologic substrate—one of the 
least understood abiotic factors interacting with precipitation—may modulate phe- 
nological responses in these forests through a combination of mechanisms regulat- 
ing water and nutrient use. We leveraged a phenological dataset from the semiarid 
island of Curaçao to examine the extent to which plant phenology at multiple levels 
of biological organization diverge under different geologies. Monthly observations 
over a 30-month period of leaves, flowers, and fruits of 69 plant species of different 
life forms at three nearby sites differing in their underlaying geology were used to 
examine intra- and inter-annual plant responses at species, community, and system 
levels. The integration of leaf, flower, and fruit observations at intra-annual scales 
revealed diverse phenological strategies among species, broad associations with geo- 
logic substrate, and the extent of intra-specific variation as a function of geology. The 
community- and system-level analyses at inter-annual scales showed a reduction in 
mean leaf scores during the 30-month period, a weak and strong leafless period in 
1993 and 1994, respectively, and differences among geologic substrates. Finally, we 
observed significant and positive relationships between precipitation and the pheno- 
phase scores; the strength of the relationships varied with phenophase and geologic 
substrate. Results of this work emphasize the importance of geologic substrate, and 
more broadly speaking landscape heterogeneity, in modulating plant phenological re- 
sponses in tropical dry forests. Ultimately, this information will become important to 
understand and mitigate global climate change impacts.
Abstract in Spanish is available with online material.

Abstract: Bioerosion caused by boring mussels (Mytilidae: Lithophaginae) can negatively impact coral reef health. During biodiversity surveys of coral-associated fauna in Curaçao (southern Caribbean), morphological variation in mussel boreholes was studied. Borings were found in 22 coral species, 12 of which represented new host records. Dead corals usually showed twin siphon openings, for each mussel shaped like a figure of eight, which were lined with a calcareous sheath and protruded as tubes from the substrate surface. Most openings surrounded by live coral tissue were deeper and funnel-shaped, with outlines resembling dumbbells, keyholes, ovals or irregular ink blotches. The boreholes appeared to contain black siphon and mantle tissue of the mussel. Because of the black color and the hidden borehole opening in live host corals, the mantle tissue appeared to mimic dark, empty holes, while they were actually cloaking live coral tissue around the hole, which is a new discovery. By illustrating the morphological range of borehole orifices, we aim to facilitate the easy detection of boring mussels for future research.

Abstract

Curaçao is a Small Island Development State in the Wider Caribbean Region. In the scope of sustainable development and the UN SDGs, these states are characterized by being extra vulnerable to environmental changes induced by climate change. One important way of adapting and mitigating is the sustainable management of natural resources such as water. Poor management of water and wastewater in particular is leading to social and environmental problems in Curaçao such as harming economical activities like fisheries and marine ecosystems. Nevertheless, social and environmental consequences of this poor management on land is hardly investigated. Therefore, this research was set up to explore the consequences on land through three approaches. First, by sorting out the current situation of wastewater monitoring in Curaçao on the managerial level by partaking in a government agency as a participant observer. Second, by exploring the occurrence of wastewater related diseases among the people of Curaçao. Third, by attempting to draw conclusions about ground water quality and its probable suitability for irrigation, by locating likely sources of wastewater pollution on the estimation of groundwater quality in Excel with secondary data of electrical conductivity. The findings include that wastewater management should be treated with more priority and that more efforts should be paid on consistency in responsibilities and storage of data. As to public health risks, the applied method did not find wastewater related diseases. Still, more thorough research on the matter is recommended. Lastly, overall groundwater quality in Curaçao is not directly suitable for irrigation. The water quality analysis with electrical conductivity provided a location to start further research where wastewater contamination might be occurring, but requires more methods to confirm whether this is actually applicable.

Abstract

This study addresses the governance around climate change policies in two small islands in the Southern Caribbean. Like many other small islands across the world it is becoming increasingly clear that they are the most vulnerable to the effects of climate change like the increase in sea level rise, longer dry periods, loss of biodiversity, more extreme weather events (flooding and hurricanes) and increased fresh water demands (IPCC, 2014). To address such issues climate change adaptation policies will be necessary. The geographical focus of this research is the Southern Caribbean, specifically the islands of Curaçao and Bonaire. This study investigated what climate change adaptation policies are in place and could the policies be characterized as good governance? Policy documents were studied, and 22 semi-structured interviews were held with policy-makers and NGOs. First, a literature review of the concept of good governance was carried out to develop an analytical framework with principles and corresponding indicators for good governance. Second, the framework was applied to assess good governance in key climate policy documents of both islands. And third, the indicators of the framework were also used in the interviews with governmental stakeholders and NGOs, to assess from their perspectives good governance in climate policies. Curaçao and Bonaire have different jurisdictions, respectively an autonomous country in the Kingdom of the Netherlands and a Dutch municipality. Therefore, from a governance perspective it seemed interesting to compare both islands whether one jurisdiction is doing better than the other. The aims of the research are to reduce the knowledge gap on climate change adaptation in the Southern Caribbean, to develop a good governance framework, to assess good governance in climate change adaptation policies on both islands and to compare them. The last aim is what recommendations of enhancing good governance practices could be given. Results are that the developed analytical framework worked rather well and that the governance principles Transparency, Inclusiveness and Connectivity are relatively better in place than Accountability and Government Effectiveness. There are some differences between the islands but not striking.

Dissolved organic carbon (DOC) release of three algal and two coral species was determined at three light intensities (0, 30–80, and 200–400 μmol photons m−2 s−1) in ex situ incubations to quantify the effect of light availability on DOC release by reef primary producers. DOC release of three additional algal species was quantified at the highest light intensity only to infer inter-specific differences in DOC release. For species tested at different light intensities, highest net release of DOC occurred under full light (200–400 μmol photons m−2 s−1). DOC released by benthic algae under full light differed (up to 16-fold) among species, whereas DOC release by scleractinian corals was minimal (Orbicella annularis Ellis and Solander, 1786) or net uptake occurred (Madracis mirabilis Duchassaing and Michelotti, 1860) independent of light availability. DOC concentrations and light intensities were also measured in situ near seven benthic primary producers, sediment, and in the water column at nine sites evenly distributed along the leeward coast of Curaçao. In situ DOC concentrations increased with light availability, although the magnitude of this positive effect differed among species and bottom types tested. In situ DOC concentrations were on average lower in November–December [87 (SD 45) μmol L−1] compared to May–June [186 (SD 136) μmol L−1], which can, at least partly, be explained by the lower light availability in the latter period. Our results suggest that DOC release by Caribbean benthic primary producers varies considerably among species and depends on light availability in reef algae. 

Abstract

Benthic cyanobacterial mats (BCMs) are impacting coral reefs worldwide. However, the factors and mechanisms driving their proliferation are unclear. We conducted a multi-year survey around the Caribbean island of Curaçao, which revealed highest BCM abundance on sheltered reefs close to urbanised areas. Reefs with high BCM abundance were also characterised by high benthic cover of macroalgae and low cover of corals. Nutrient con- centrations in the water-column were consistently low, but markedly increased just above substrata (both sandy and hard) covered with BCMs. This was true for sites with both high and low BCM coverage, suggesting that BCM growth is stimulated by a localised, sub- strate-linked release of nutrients from the microbial degradation of organic matter. This hy- pothesis was supported by a higher organic content in sediments on reefs with high BCM coverage, and by an in situ experiment which showed that BCMs grew within days on sedi- ments enriched with organic matter (Spirulina). We propose that nutrient runoff from urban- ised areas stimulates phototrophic blooms and enhances organic matter concentrations on the reef. This organic matter is transported by currents and settles on the seabed at sites with low hydrodynamics. Subsequently, nutrients released from the organic matter degra- dation fuel the growth of BCMs. Improved management of nutrients generated on land should lower organic loading of sediments and other benthos (e.g. turf and macroalgae) to reduce BCM proliferation on coral reefs.