Caribbean

Avian reproduction is a process that requires extensive energetic input by parents, particularly in pelagic seabirds. Parental infanticide has rarely been reported in pelagic seabirds, and its frequency among taxa is therefore difficult to determine. Using data from remote cameras, two cases of probable parental infanticide in Red-billed Tropicbirds Phaethon aethereus were captured on Sint Eustatius in the 2021–2022 breeding season. Both cases are presented with images collected from remote cameras as evidence. While appearing counterproductive, parental infanticide may provide an alternative reproduction strategy that favors lifetime reproductive success over short term success.

Management of reef fish populations requires insight in their resilience to anthropogenic stressors. Studies on temporal variations in reef fish populations and their abundance responses to environmental changes are crucial to the development of ecosystem-based management.

Seventeen years of voluntary fish survey data of reef fish at the west coast of Bonaire Marine Park (Caribbean) were analysed to investigate the effect of environmental changes on local reef fish populations. Various anthropogenic stressors that influence the coral reefs of Bonaire were studied in recent years, this study focusses on population responses to loss of coral cover, the establishment of a fishery protected area, and reef fishery pressure. In addition, reef fish responses to specific events were analysed at species or family level.

In general fluctuations in sighting frequencies were species-specific and difficult to interpret. Three large parrotfish decreased by approximately 50% over time and there were indications of a negative trend in mid-sized parrotfish as well. In fishery targets, the most intensive fished group (large to mid-sized grouper species), decreased strongly. After their abundance decreased to near zero, two species belonging to other fish families showed signs of sequential overfishing. It is unclear if larval import will compensate for the loss in reproductive capacity of the species in decline, recent literature on recruitment distances suggest that the level of self recruitment is high in Bonaire. An exception to short recruitment distances was noted earlier in the balloon fish Diodon holocanthus. The data suggest that the balloon fish population till 2010 originated from the mass recruitment in 1994, from the start of the studied period in 2000 to 2010 their abundance steadily declined to near zero. Another event with direct effect on population dynamics is the mass mortality events in moray eels in 2008. With a lag time of a year, especially two Enchelycore species strongly declined afterwards, which could elucidate the highly variable population densities of these species over the period. A following moray eel mass mortality event in 2022, also occurred at the onset of a period of sea water warming, paralleling various reef fish species in the Red Sea. Increase in warming events carries the risk of more frequent mass mortalities.

https://www.frontiersin.org/articles/10.3389/fmars.2023.1187249/abstract

In situ testing of candidate odorant cues directly in coral-reef communities has the advantage that, in principle, it permits the behavioral responses of all fish species to be evaluated in the species' natural environments. The success of in situ testing depends critically, however, on a suitable method of odorant release. We provide here a proof-of-concept for a new method of release that (instead of using distilled water as an ejection medium) ejects odorant-containing local reef water remotely and silently over an extended time period using gravity as the motive force. The ejected water, being neutrally buoyant, remains in the reef community, dispersing in local currents. From our observations of fish behavior during ejection of candidate odorants in Curaçao reefs, we confirm that brown chromis (Chromis multilineata) are likely attracted to dimethylsulfoniopropionate (DMSP), and we obtain suggestive evidence that they are attracted to a mix of three betaines: glycine betaine, proline betaine, and trigonelline. Creole wrasse (Clepticus parrae) and yellowhead wrasse (Halichoeres garnoti) are likely repelled by DMSP.Many observed fish species gave no evidence of being affected by either DMSP or betaines.

Abstract
The vegetation database CACTUS (registered in GIVD under SA-00-004) aims to bring together all plot-based relevés from the Dutch Caribbean Islands that are available from literature, unpublished resources, and recent field surveys. The database currently contains 2,701 vegetation descriptions. The database is used for vegetation classification, to investigate vegetation change over time, to assist in the planning of vegetation surveys, as a source for plant species distribution maps, and to inform nature conservation and policy.

DOI: 10.3897/VCS.101114

Papiamento, Papiamentu, and Dutch below. 

Manta rays are highly charismatic creatures that inhabit the waters of the Dutch Caribbean. In addition to being a highly prized find for divers and snorkelers, they are also important for healthy oceans as they can help control plankton and cycle nutrients. Manta rays are threatened by a variety of human activities. Luckily, increased protection for the giant oceanic manta ray in the Caribbean region will be considered in the next Conference of Parties for the Cartagena Convention (COPS) meeting later this year on Aruba.  

Manta Rays in the Caribbean 

The Caribbean is home to two species of manta ray, the giant oceanic manta ray (Mobula birostris) and Caribbean manta ray (Mobula cf. Birostris-which will most likely be officially described in the coming years),  as well as several species of devil rays. Manta rays are the largest type of rays and pose no danger to humans. 

Manta rays are filter feeders, taking in microscopic food (plankton), including fish larvae, krill, shrimp, and planktonic crabs from the water column and filtering them through their gill plates. They play a vital role in keeping the oceans healthy by regulating plankton levels. Also, by moving between the surface ocean, deep sea and coral reefs, they create a valuable ecological connection by transporting nutrients. 

Giant manta ray. Photo credit: Rudy Van Geldere

Threats 

Manta rays are threatened by a variety of human activities. One of the biggest threats to these creatures worldwide is overfishing, as they are often targeted for their gill plates, used in Traditional Chinese Medicine. They are also at risk from bycatch, entanglement, habitat destruction, and pollution. Bycatch and entanglement are likely the two biggest threats in the Caribbean. 

Manta rays are the largest species of rays, are long-lived (30-50 years) and are slow to reproduce. It is estimated that giant manta rays are not able to reproduce until they reach an age of 9-12 years old, after which, they are only able to produce one pup at a time. This slow life cycle and low reproduction rate make manta rays extremely vulnerable to depletion. 

Photo credit: Pieter de Groot

Hope on the horizon 

In the Dutch Caribbean, marine protected areas, such as the Yarari Marine Mammal and Shark Sanctuary, help protect manta and devil rays. The species are also on several regional and international lists, such as the Convention on International Trade in Endangered Species (CITES), the Convention on the Conservation of Migratory Species of Wild Animals (CMS) and International Shark Strategy adopted by the Dutch Government (2019).  

In addition, the Kingdom of Netherlands, along with the Republic of France, has formally submitted a proposal to include the giant manta in Annex II of the Specially Protected Areas and Wildlife (SPAW) Protocol, a regional agreement for the protection and sustainable use of coastal and marine biodiversity in the Wider Caribbean Region. If approved during the next Conference of Parties for the Cartagena Convention (COPS) IGM20/COP17 this year on Aruba, this measure will provide a legal framework for the highest level of protection for the conservation of the giant manta ray. 

Giant manta ray. Photo credit: Danielle de Kool

Report your sightings 

By submitting your (old and new) sightings of manta (and devil) rays, you can help researchers and conservationists learn more and better protect these species. You can report your sightings via  Caribbean Islands Manta Conservation Program or Observation.org and associated free app ObsIdentify– which will help you automatically identify the species by uploading your photos. In addition, you could also submit your photos via Mantatrust.org/IDtheManta, email (caribbean.islands@mantatrust.org) or through the Caribbean Islands Manta Conservation Program social media pages on Facebook and Instagram.  If uploading images to social media, particularly Instagram, tag@Caribbeanislandsmanta in your uploads to make sure these images are easily found and included in the global database. 

DCNA 

The Dutch Caribbean Nature Alliance (DCNA) supports science communication and outreach in the Dutch Caribbean region by making nature-related scientific information more widely available through amongst others the Dutch Caribbean Biodiversity Database, DCNA’s news platform BioNews and the press. This article contains the results from several scientific studies but the studies themselves are not DCNA studies. No rights can be derived from the content. DCNA is not liable for the content and the in(direct) impacts resulting from publishing this article.  

More information 

https://dcnanature.org/report-manta-rays/ 

https://gefcrew.org/carrcu/SPAWSTAC10/SPAW_STAC10_WG.43%20INF.23%20EN%20Listing%20of%20Giant%20Manta%20Ray.pdf 

https://www.mantatrust.org/caribbean-islands 

https://swimwithmantas.org/ 

Mantaroggen zijn zeer charismatische dieren die in de wateren van de Nederlands Caribisch gebied voorkomen. Behalve dat ze een zeer gewaardeerde vondst zijn voor duikers en snorkelaars, zijn ze ook belangrijk voor gezonde oceanen, omdat ze kunnen helpen bij het circuleren van voedingsstoffen. Mantaroggenworden bedreigd door verschillende menselijke activiteiten. Gelukkig zal tijdens de volgende bijeenkomst van de Conference of Parties forthe Cartagena Convention (COPS) later dit jaar op Aruba worden overwogen om de reuzenmanta in het Caribisch gebied beter te beschermen. 

Mantaroggen in het Caribisch gebied 

Het Caribisch gebied is de thuisbasis van twee soorten mantaroggen, de reuzenmanta (Mobula birostris) en Caribische mantaroggen (Mobula cf. Birostris – die hoogstwaarschijnlijk in de komende jaren officieel zal worden beschreven), evenals verschillende soorten duivelsroggen. Mantaroggen zijn de grootste soort roggen. Ze vormen geen gevaar voor de mens. 

Mantaroggen zijn filtervoeders, die microscopisch klein voedsel (plankton), waaronder vislarven, krill, garnalen en planktonische krabben uit de waterkolom opnemen en door hun kieuwplaten filteren. Ze spelen een cruciale rol bij het gezond houden van de oceanen door het planktongehalte te reguleren. Door zich te verplaatsen tussen de oceaan aan het oppervlak, de diepzee en koraalriffen, creëren ze ook een waardevolle ecologische verbinding door voedingsstoffen te transporteren. 

Gianta manta ray . Photo credit: Rudy Van Geldere

Gevaren 

Mantaroggen worden bedreigd door verschillende menselijke activiteiten. Een van de grootste bedreigingen voor deze dieren wereldwijd is overbevissing, omdat ze vaak het doelwit zijn voor hun kieuwplaten, die in de traditionele Chinese geneeskunde worden gebruikt. Daarnaast worden ze ook bedreigd door bijvangst, verstrikking (in bijvoorbeeld visnetten en vislijnen), verdwijnen van leefgebieden en vervuiling. Bijvangst en verstrikking zijn waarschijnlijk de twee grootste bedreigingen in het Caribisch gebied. 

De mantaroggen zijn de grootste soorten roggen, ze leven lang (30-50 jaar) en planten zich langzaam voort. De leeftijd waarop reuzenmantaroggen zich voor het eerst kunnen voortplanten, wordt geschat op ongeveer 9-12 jaar oud en mantaroggen krijgen slechts één pup per keer. De langzame levenscyclus en langzame voortplanting maken mantaroggen uiterst kwetsbaar voor uitsterving. 

Photo credit: Pieter de Groot

Hoop aan de horizon 

In het Nederlands Caribisch gebied helpen beschermde mariene gebieden, zoals het Yarari Marine Mammal and Shark Sanctuary, mantas en duivelsroggen te beschermen. De soort staat ook op verschillende regionale en internationale lijsten, zoals de Convention on International Trade in Endangered Species (CITES), de Convention on the Conservation of Migratory Species of Wild Animals (CMS) en de Internationale Haaien Strategie aangenomen door de Nederlandse regering (2019). 

Daarnaast heeft het Koninkrijk der Nederlanden samen met de Republiek Frankrijk formeel een voorstel ingediend om de reuzenmanta op te nemen in bijlage II van het Specially Protected Areas and Wildlife (SPAW) Protocol, een regionale overeenkomst voor de bescherming en duurzaam gebruik van kust- en mariene biodiversiteit in de bredere Caribische regio. Indien goedgekeurd tijdens de volgende Conference of Parties for the Cartagena Convention (COPS) dit jaar op Aruba, zal deze maatregel een wettelijk kader bieden voor het hoogste niveau van bescherming voor het behoud van de reuzenmanta. 

Giant manta ray. Photo credit: Danielle de Kool

Meld uw waarnemingen 

Door uw (oude en nieuwe) waarnemingen van mantaroggen (en duivelsroggen) in te dienen, kunt u onderzoekers en natuurbeschermers helpen meer te leren en deze soorten beter te beschermen. U kunt uw waarnemingen melden via Caribbean Islands Manta Conservation Program of Observation.org en de bijbehorende gratis app ObsIdentify, waarmee u de soort automatisch kunt identificeren door uw foto’s te uploaden. Daarnaast kunt u uw foto’s ook indienen via Mantatrust.org/IDtheManta, e-mail (caribbean.islands@mantatrust.org) of via de social media-pagina’s van het Caribbean IslandsManta Conservation Program op Facebook en Instagram. Als u afbeeldingen uploadt naar sociale media, met name Instagram, tag dan @Caribbeanislandsmanta in uw uploads om ervoor te zorgen dat deze afbeeldingen gemakkelijk kunnen worden gevonden en opgenomen in de wereldwijde database. 

DCNA 

De  Dutch Caribbean Nature Alliance (DCNA) ondersteunt wetenschapscommunicatie en outreach in de Nederlandse Caribische regio door natuurgerelateerde wetenschappelijke informatie breder beschikbaar te maken via onder andere de Dutch Caribbean Biodiversity Database, DCNA’s nieuwsplatform  BioNews en de pers. Dit artikel bevat de resultaten van verschillende wetenschappelijke onderzoeken, maar de onderzoeken zelf zijn geen DCNA-onderzoeken. Aan de inhoud kunnen geen rechten worden ontleend. DCNA is niet aansprakelijk voor de inhoud en de indirecte gevolgen die voortvloeien uit het publiceren van dit artikel. 

Meer informatie

https://dcnanature.org/report-manta-rays/ 

https://gefcrew.org/carrcu/SPAWSTAC10/SPAW_STAC10_WG.43%20INF.23%20EN%20Listing%20of%20Giant%20Manta%20Ray.pdf 

https://www.mantatrust.org/caribbean-islands 

https://swimwithmantas.org/ 

E mantanan ray ta criaturanan masha carismatico cu ta biba den e awanan di Caribe Hulandes. Ademas di ta un hayazgo masha aprecia pa e buceadonan y hende cu ta snorkel, nan ta importante tambe pa salud di e oceanonan, ya cu nan por yuda na controla plankton y recicla e nutrientenan. E mantanan ray ta wordo menasa pa un variedad di actividad humano. Afortunadamente, nan lo considera un miho proteccion pa e mantanan oceanico gigante den region di Caribe den e proximo reunion di Conferencia di e Partidonan pa e Convencion di Cartagena (COPS) na final di e aña aki na Aruba. 

Manta ray den Caribe 

Caribe ta e hogar di dos especie di manta, e manta ray oceanico gigante (Mobula birostris) y e manta ray Caribense (Mobula cf. Birostris-, cu masha probablemente lo wordo describi oficialmente den e proximo añanan), mescos tambe varios especie di manta diablo. Manta ray ta e tipo mas grandi di raya. Nan no ta representa ningun peliger pa hende. 

Manta ray ta alimenta nan mes door di filtracion, nan ta absorba alimento microscopico (plankton), incluyendo larva di pisca, krill, cabaron y cangreu planctonico di e columna di awa y ta filtra esaki a traves di nan plachinan di caicay. Nan ta hunga un rol hopi importante den mantencion di salud di e oceanonan mediante regulacion di e nivelnan di plankton. Ademas, door di move entre e superficienan di oceano, e profundidadnan di lama y e rifnan di coral, nan ta crea un conexion ecologico valioso mediante transporte di nutriente. 

Credito di e potret: Rudy Van Geldere

Menasanan 

E mantanan ray ta wordo menasa pa un variedad di actividad humano. Un di e mayor menasanan pa e criaturanan den henter mundo ta sobrepesca, ya cu hopi biaha nan ta e obhetivo pa mitibo di nan plachinan di caicay, cu ta wordo uza den medicina tradicional. Tambe ta den riesgo di captura incidental, enredo, destruccion di habitat y contaminacion. Captura incidental y enredo ta probablemente e dos menasanan mas grandi den Caribe. 

E mantanan ray ta e especie mas grandi di raya, nan ta biba largo (30-50 aña) y ta pocopoco den reproduccion di nan mes. E edad den cua e mantanan gigante por reproduci nan mes pa prome biaha ta calcula alrededor di 9-12 aña y e mantanan ta duna luz solamente na un cria cada biaha. E ciclo di bida lento y e velocidad abou di reproduccion ta haci cu e mantanan ta extremadamente vulnerabel na agotamento. 

Credito di e potret: Pieter de Groot

Speransa den horizonte 

Den Caribe Hulandes  e areanan marina proteha, manera Yarari Marine Mammal and Shark Sanctuary, ta yuda proteha e mantanan y e mantanan diablo. Bo ta haya e especienan tambe den varios lista regional y internacional, manera Convention on International Trade in Endangered Species (CITES), Convention on the Conservation of Migratory Species of Wild Animals (CMS) y International Shark Strategy adopta pa Gobierno Hulandes (2019) 

Ademas Reino di e Paisnan Hulandes hunto cu Republica di Francia a presenta formalmente un proposicion pa inclui e manta gigante den e Anexo II di Specially Protected Areas and Wildlife (SPAW) Protocol, un acuerdo regional pa proteccion y uzo sostenibel di Biodiversidad di costa y marino den Region di Gran Caribe. Si esaki keda aproba durante e proxima Conferencia di e Partinan pa e Convencion di Cartagena (COPS) IGM20/COP17 e aña aki na Aruba, e medida aki lo proporciona un marco legal pa e nivel mas halto di proteccion pa conservacion di e manta ray gigante. 

Credito di e potret: Danielle de Kool

Raporta bo observacionnan 

Door di manda bo observacionnan (bieu y nobo) di manta ray (y diablo), por yuda e investigadonan y conservacionistanan pa siña mas y proteha miho e especienan aki. Por informa bo observacionnan a traves di Programa di Conservacion di Manta di e Islanan di Caribe of Observation.org y e aplicacion gratis asocia ObsIdentify, cu lo yuda identifica e especienan cu bo a download nan potret  automaticamente. Ademas, tambe por manda potret a traves di Mantatrust.org/IDtheManta, correo electronico (caribbean.islands@mantatrust.org) of a traves di e pagina di rednan social di Programa di Conservacion di Manta di e Islanan di Caribe riba Facebook y Instagram. Si bo upload imagen riba e rednan social, particularmente riba Instagram, tag e ora @Caribbeanislandsmanta den bo uploadnan pa sigura cu e imagennan aki por wordo haya facilmente y ta wordo inclui den e base di dato global. 

DCNA 

The Dutch Caribbean Nature Alliance (DCNA) pa Naturalesa ta sostene comunicacion cientifico y  divulgacion den region di Caribe Hulandes door di haci cu e informacion cientifico relaciona cu naturalesa ta mas disponibel a traves di entre otro, Dutch Caribbean Biodiversity Database, e plataforma di noticia BioNews di DCNA y prensa.E articulo aki ta contene e resultadonan di varios estudio cientifico, pero e estudionan riba nan mes no ta estudio di DCNA. No tin derecho pa saca nada di e contenido. DCNA no ta responsabel pa e contenido y e impactonan indirecto cu resulta di e publicacion di e articulo aki. 

Mas informacion

https://dcnanature.org/report-manta-rays/ 

https://gefcrew.org/carrcu/SPAWSTAC10/SPAW_STAC10_WG.43%20INF.23%20EN%20Listing%20of%20Giant%20Manta%20Ray.pdf 

https://www.mantatrust.org/caribbean-islands 

https://swimwithmantas.org/ 

Chuchu ta kreashonnan masha karismátiko ku ta biba den laman di Karibe Hulandes. Banda di e echo ku nan ta un hayasgo sumamente apresiá pa sambuyadónan i hendenan ku ta snòrkel, nan ta importante tambe pa oséano salú, pasobra nan por yuda ku dominio di planktòn i e siklo di nutriente. Chuchu ta bou di menasa di un variedat di aktividat di hende. Afortunadamente durante e siguiente enkuentro di Conference of Parties for the Cartagena Convention (COPS) mas lat e aña akí na Aruba, lo konsiderá pa protehá e manta oseániko gigantesko mas mihó den área karibense.  

Chuchu den área karibense 

Área karibense ta kas pa dos espesie di chuchu, e manta oseániko gigantesko (Mobula birostris) i chuchu karibense (Mobula cf. Birostris – ku mui probablemente lo keda deskribí ofisialmente den e añanan binidero), meskos ku vários espesie di e chuchu ku na ingles nan ta yama ‘devil ray’. Manta ta e espesie mas grandi di chuchu. Nan no ta forma un peliger pa hende. 

Chuchu ta kome pa medio di filtrashon. Nan ta saka kuminda mikroskópiko (planktòn), entre otro larva di piská, krill, kabaron i kangreu planktóniko for di e kolumna di awa i ta filtra esakinan atraves di nan plachinan di kaikai. Nan ta hunga un ròl krusial den tenementu di oséano salú pa medio di regulá e nivel di planktòn. Pa medio di move entre superfisie di oséano, profundidat di laman i e refnan di koral, nan ta krea tambe un konekshon ekológiko balioso mediante transporte di supstansianan nutritivo. 

Potrèt: Rudy Van Geldere

Peliger 

Chuchu ta bou di menasa debí na un variedat di aktividat di hende. Un di e menasanan mas grandi mundialmente pa e kreashonnan akí ta sobrepeska, pasobra hopi biaha hende ta yag riba nan pa motibu di nan plachinan di kaikai, ku nan ta usa den medisina tradishonal. Nan ta kore riesgo tambe pa motibu di kaptura insidental, pegamentu den reda, destrukshon di nan hábitat i kontaminashon. Kaptura insidental i pegamentu den reda probablemente ta e dos menasanan mas grandi den área karibense. 

Manta ta e espesie mas grandi di chuchu, nan ta biba hopi tempu (30 pa 50 aña) i nan ta prokreá pokopoko. Nan ta balotá e edat ku e manta gigantesko por prokreá pa promé biaha na mas òf ménos 9 pa 12 aña i kada biaha manta ta haña solamente un yu. E siklo di bida pokopoko i e velosidat abou di reprodukshon ta hasi ku e mantanan ta sumamente vulnerabel pa kada biaha bira ménos. 

Potrèt: Pieter de Groot

Speransa na horizonte 

Den Karibe Hulandes áreanan marino protehá, manera Yarari Marine Mammal and Shark Sanctuary, ta yuda protehá manta i ‘devil ray’. E espesie akí ta riba diferente lista regional i internashonal tambe, manera e Convention on International Trade in Endangered Species (CITES), e Convention on the Conservation of Migratory Species of Wild Animals (CMS) i e International Shark Strategy ku gobièrnu hulandes a adoptá na aña 2019. 

Banda di esaki Reino Hulandes huntu ku Repúblika di Fransia formalmente a entregá un proposishon pa inkluí e manta gigantesko den e anekso II di Specially Protected Areas and Wildlife (SPAW) Protocol, un akuerdo regional pa protekshon i uso sostenibel di biodiversidat na kosta i biodiversidat marino den e region karibense mas amplio. Den kaso ku e próksimo Conference of Parties for the Cartagena Convention (COPS) IGM20/COP17 e aña akí na Aruba aprobá e medida akí, esaki lo ofresé un kuadro legal pa e nivel mas haltu di protekshon pa konservashon di e manta gigantesko.  

Potrètt: Danielle de Kool

Mèldu bo opservashonnan 

Pa medio di entregá bo opservashonnan (bieu i nobo) di chuchu i ‘devil ray’, bo por yuda investigadónan i protektornan di naturalesa pa siña mas i protehá e espesienan akí mas mihó. Bo por mèldu bo opservashonnan via Caribbean Islands Manta Conservation Program of Observation.org i e app korespondiente grátis ObsIdentify, ku bo por identifiká e espesie outomátikamente kuné pa medio di upload bo potrètnan. Aparte di esaki bo por entregá bo potrètnan tambe via Mantatrust.org/IdtheManta, email (caribbean.islands@mantatrust.org) òf via e pagínanan di medionan sosial di Caribbean Islands Manta Conservation Program riba Facebook i Instagram. Ora bo upload potrèt riba medionan sosial, spesialmente Instagram, tag e ora ei @Caribbeanislandsmanta den bo uploadnan pa sòru ku nos por haña i inkluí e potrètnan akí fásilmente den e database mundial. 

DCNA 

Dutch Caribbean Nature Alliance (DCNA) ta sostené komunikashon sientífiko i ‘outreach’ den region Hulandes Karibense pa medio di hasi informashon sientífiko relashoná ku naturalesa mas ampliamente disponibel via entre otro  Dutch Caribbean Biodiversity Database, DCNA su plataforma di notisia  BioNews  i prensa. E artíkulo akí ta kontené resultado di diferente investigashon sientífiko, pero e investigashonnan mes no ta investigashon di DCNA. No por derivá ningun derecho for di e kontenido. DCNA no ta responsabel pa e kontenido i e konsekuensianan (in)direkto ku ta surgi for di publikashon di e artíkulo akí. 

Mas informashon

https://dcnanature.org/report-manta-rays/ 

https://gefcrew.org/carrcu/SPAWSTAC10/SPAW_STAC10_WG.43%20INF.23%20EN%20Listing%20of%20Giant%20Manta%20Ray.pdf 

https://www.mantatrust.org/caribbean-islands 

https://swimwithmantas.org/ 

Published in BioNews 64

Abstract: The economies of small tropical islands often benefit from large-scale tourism, attracted by
the guarantee of beach facilities, sun and warmth, landscape beauty, and cultural and underwater
life. While these are highly valued assets, it is unclear how local communities benefit from tourism,
or how they perceive their natural environment, which has been the basis for their rich cultural
history. Against this background, the main aim of this article is to investigate inhabitants’ perceptions
about locals’ inclusiveness in tourism and recreation on a small island called Bonaire. A total of
400 households were interviewed during the period November 2021–February 2022. Inclusiveness in
tourism and the welfare it brings are judged as low, based on the findings in this study. With a share
of around 40% of the population of Dutch Caribbean islanders living in poverty, the challenge of
inequality is urgent. While environmental degradation contributes to inequality, inequality can also
contribute to environmental degradation. To reduce inequalities, while ensuring life below water and
life on land, the handling of poverty is one of the most critical bottlenecks in this society.

A B S T R A C T

Fish assemblages of different types of artificial reefs can differ greatly in abundance, biomass and composition, with some reef types harboring over five times more herbivores than others. It is assumed that higher herbivorous fish abundance results in a higher grazing intensity, affecting the benthic community by means of enhanced coral recruitment, survival and growth. Territorial fish species might affect this process by chasing away other fish, especially herbivores. In this study we compared the fish assemblage, territorial behavior and grazing intensity by fish on two artificial reef types: reef balls and layered cakes, differing greatly in their fish assemblage during early colonization. In addition, the effect of artificial reef type on benthic development and coral recruitment, survival and growth, was investigated. Although layered cakes initially harbored higher herbivorous fish biomass, this effect was lost during consecutive monitoring events. This seems to be the result of the higher territorial fish abundance around the layered cakes where almost four times more chasing behavior was recorded compared to the reef balls. This resulted in a more than five times lower fish grazing intensity compared to the reef-ball plots. Although macroalgae were effectively controlled at both reefs, the grazing intensity did not differ enough to cause large enough structural changes in benthic cover for higher coral recruitment, survival or growth. The high turf algae cover, combined with increasing crustose coralline algae and sponge cover likely explained reduced coral development. We recommend further research on how to achieve higher grazing rates for improved coral development on artificial reefs, for example by facilitating invertebrate herbivore. 

MSc internship report

The project Restoration of resilience of nature and society in the Caribbean Netherlands aims to improve the resilience of the coral reefs in the BES (Bonaire, Sint Eustatius, Saba) islands, by mitigating the local stressors. One of the methodologies used is water quality monitoring. For this research, the focus was on chlorophyll a and turbidity temporal and spatial variability in Saba, and on how this could be related to anthropogenic and natural land-based local stressors. Chlorophyll a is a key water quality parameter which can give an insight on the eutrophic state of an area, while turbidity can be used as an indicator for coastal erosion and run-offs. These parameters were measured in 13 sampling sites, bi-weekly from May to August 2022, using two CTDs, a sensitive sensor technology. The land-based stressors were mapped as a result of qualitative analysis. Chlorophyll a values were highly variable, and often exceeded the safety threshold (0.2 μg/L) previously chosen, suggesting that the area was in a chronic state of eutrophication. Turbidity instead remained more stable and nearly always below the 3 NTU threshold. On one hand, spatial variability was not always directly linked to land-based stressors, and might be better interpreted including the action of sea currents. Temporal fluctuations, on the other hand, can be only partly explained by the amount of rainfall increasing run-offs from land to sea. Moreover, further research is needed to quantify local stressors, and long-term monitoring is necessary to fully understand the amplitude and nature of their influence on water quality.

For full report or more information,  please contact erik.meesters@wur.nl or gulsah.dogruer@wur.nl

The 1983-1984 die-off of the long-spined sea urchin Diadema antillarum stands out as a catastrophic marine event because of its detrimental effectson Caribbean coral reefs. Without the grazing activities of this key herbivore, turf and macroalgae became the dominant benthic group, inhibiting coral recruitment and compromising coral reef recovery from other disturbances. In the decades that followed, recovery of D. antillarum populations was slow to non-existent. In late January 2022, a new mass mortality of D. antillarum was first observed in the U.S. Virgin Islands. We documented the spread and extent of this new die-off using an online survey. Infected individuals were closely monitored in the lab to record signs of illness, while a large population on Saba, Dutch Caribbean, was surveyed weekly before and during mortality to determine the lethality of this event. Within four months the die-off was distributed over 1,300 km from north to south and 2,500 km east to west. Whereas the 1983-1984 die-off advanced mostly with the currents, the 2022 event has appeared far more quickly in geographically distant areas. First die-off observations in each jurisdiction were often close to harbor areas, which, together with their rapid appearance, suggests that anthropogenic factors may have contributed to the spread of the causative agent. The signs of illness in sick D. antillarum were very similar to those recorded during the 1983-1984 die-off: lack of tube feet control, slow spine reaction followed by their loss, and necrosis of the epidermis were observed in both lab and wild urchins. Affected populations succumbed fast; within a month of the first signs of illness, a closely monitored population at Saba, Dutch Caribbean, had decreased from 4.05 individuals per m2 to 0.05 individuals per m2. Lethality can therefore be as high as 99%. The full extent of the 2022 D. antillarum die-off event is not currently known. The slower spread in the summer of 2022 might indicate that the die-off is coming to a (temporary) standstill. If this is the case, some populations will remain unaffected and potentially supply larvae to downstream areas and augment natural recovery processes. In addition, several D. antillarum rehabilitation approaches have been developed in the past decade and some are ready for large scale implementation. However, active conservation and restoration should not distract from the primary goal of identifying a cause and, if possible, implementing actions to decrease the likelihood of future D. antillarum die-off events.

Abstract

Invasive alien species (IAS) are species that have been introduced to locations outside of their distributional range via human transport. In their novel exotic range, these species reach quickly reproduce and/or spread, hence the connotation “invasive”. Examples of well-known problematic IAS include tropical mosquitos bearing diseases such as Zika virus, predatory animals such as the lionfish or black rats, and plants blanketing anything they encounter. IAS are considered to be a major threat to biodiversity with extensive societal and economic consequences. However, invasive species do not become invasive overnight; invasion is the final and most detrimental stage of a much longer process. The aim of this thesis was to disentangle the natural and anthropogenic causes and consequences of species invasion by following exotic species from their origin to their impact. This thesis is structured along the different stages of species invasion and answers three overall research questions: Where do exotic species come from?; Where do exotic species end up?; What are the consequences of exotic species invasion?. The first question Where do exotic species come from? is answered in Chapter 2 that showed that exotic species and species endangered with extinction inhabit the same locations but contrast each other in terms of their traits. Both groups are overrepresented on human-impacted oceanic islands. The question: Where do exotic species end up? is answered by Chapters 3-5. In this section I conclude that within islands invaded by several exotic reptiles, these species are found almost exclusively in human-impacted environments with open or shrubby vegetation. Conversely, native species reach highest abundances in forest sites (Chapter 3). Hurricanes severely alter available habitats for reptiles (Chapter 4). Native species abundances of the lizard genus Anolis decreased with increasing levels of hurricane-induced habitat change, especially on St. Martin that was severely hit by the hurricanes Irma and Maria. Exotic species varied in their response, but we detected exotic species in previously uninvaded forests. That species from small, less populated islands also get introduced was demonstrated by the first published record of an exotic Saban anole (A. sabanus) found in the harbor of St. Eustatius (Chapter 5). This chapter serves as proof of concept that shipping is an important vector for exotic reptiles. The question What are the consequences of species invasion? is answered in Chapters 6-8, featuring the extensive invasion of the Coralita vine (A. leptopus) on St. Eustatius, impacting approximately one-third of this island. Coralita significantly alters the species composition of arthropod communities on St. Eustatius. After invasion the unique communities in urban and natural sites become homogenized to the point where they become undistinguishable (Chapter 6). The plant also has societal consequences through the reduced availability of ecosystem services (ES) (Chapter 7-8). Through a novel methodology we were able to provide estimates of ES value loss to the economy of St. Eustatius (Chapter 7-8), amounting to 42.000 dollar per year in case 3% of the island would be dominantly covered by the plant, rising to 640.000 dollar per year in case the entire range of Coralita would reach dominant coverage. We estimate that it requires a total investment of 12,7 million dollars (12% of GDP) to revert back from the worst case scenario to a Coralita-free situation. In general based on the work in this thesis I can conclude that the process of species invasion is 1) to some extent predictable at its various stages; 2) an important, independent driver of change augmented by several natural and anthropogenic factors; and 3) has major consequences for biological systems as well as human welfare and wellbeing through invasion-induced changes in ecosystem services.

https://research.vu.nl/en/publications/biodiversity-in-a-globalized-worl...