Jellyfish swarms and degree of exposure and vulnerabil-ity of recreational and tourist activities on beaches. Methodological approach to their assessment in the Lagos-Ferrara sector (Málaga, Spain)

An important part of the economy of the municipalities on the southern Spanish coast revolves around tourist activity, whose main attraction is the sun and beach. Events such as the arrival of swarms of jellyfish on their beaches have generated a certain amount of fear in the tourism sector. This work presents a methodological essay to evaluate the possible impact of this phenomenon on the use of the beach and the tourist economic activity linked to it. The chosen study area is the stretch of coast between the beach-es of "Lagos" and "Ferrara" (eastern coast of the province of Málaga). It is developed from a risk management perspective, addressing exposure and vulnerability factors. The sources are mainly surveys. The results show that in the short term there are no clear consequences, but there are in the long term.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Effects of environmental variables on the distribution of juvenile cubomedusae Carybdea marsupialis in the coastal Western Mediterranean

[EN] Relationships between environmental factors and oscillations in jellyfish abundance, especially in the early life stages, could help to interpret past increases and also predict scenarios in a changing future. For the first time, we present cubozoan spatial and temporal distributions in the earliest stages and their relationships with different factors. Abundances ofCarybdea marsupialismedusae showed high interannual variability from 2008 to 2014 along the Denia coast (SE Spain, W Mediterranean). During 2015, samples were collected from 11 beaches along 17 km of coastline, 8 times from January to November in order to determine the effects of environmental factors on the distribution of juvenileC.marsupialis. Juveniles (<= 15 mm diagonal bell width) were present from May to July, with more sampled near shore (0-15 m). Most of them occurred in June when their numbers were unequal among beaches (average 0.05 ind m(-3), maximum 6.71 ind m(-3)). We tested distributions of juveniles over time and space versus temperature, salinity, nutrients (N, P and Si), chlorophyll-a(Chl-a), and zooplankton abundance. Temperature and cladocerans (zooplankton group) were significantly positively correlated with juvenile distribution, whereas Chl-aconcentration was weakly negative. By contrast, in 2014, high productivity areas (Chl-aand zooplankton) overlapped the maximum adult abundance (5.2 ind m(-3)). The distribution of juveniles during 2015 did not spatially coincide with the areas where ripe adults were located the previous year, suggesting that juveniles drift with the currents upon release from the cubopolyps. Our results yield important insights into the complexity of cubozoan distributions.This study has received funding through European Commission's LIFE programme [LIFE08 NAT ES64 CUBOMED.eu to C.B. from the Alicante University and V.L.F. from the Institute of Marine Science, CSIC, Spain], and from the D.G Sostenibilidad de la Costa y el Mar from the Spanish Ministry of Agriculture, Food and the Environment, the Fundacion Biodiversidad, and the D.G. Agua -Generalitat Valenciana. It has also received support from Parques Nacionales and Ajuntament de Denia. We are grateful for the collaboration of Fundació Baleària, Marina El Portet de Dénia and Marina de Dénia. This work is a contribution from the ¿Ramon Margalef¿ Environmental Research Institute (IMEM) from the University of Alicante, Spain. We are especially grateful for the sampling and laboratory support provided in the Montgó Research Station by NGO ACIF Marina Alta volunteers: Ángela Alba, Ainara Ballesteros, Miguel Escolano, Ángel Fernández, Marta Gil, Héctor Gutiérrez, Ainara Lacalle and Alba Pérez. We would also like to extend our thanks to Jordi Alventosa and Júlia Escrivá from IGIC-Polytechnic Valencia University for their contribution to nutrient analysis. Editing services were provided by Sea Pen Scientific Writing.Bordehore, C.; Fonfría, E.; Alonso, C.; Rubio-Tortosa, B.; Acevedo, M.; Canepa, A.; Falco, S.... (2020). Effects of environmental variables on the distribution of juvenile cubomedusae Carybdea marsupialis in the coastal Western Mediterranean. PLoS ONE. 15(6):1-20. https://doi.org/10.1371/journal.pone.0230768S120156Purcell, J., Uye, S., & Lo, W. (2007). Anthropogenic causes of jellyfish blooms and their direct consequences for humans: a review. Marine Ecology Progress Series, 350, 153-174. doi:10.3354/meps07093Graham, W. M., Gelcich, S., Robinson, K. L., Duarte, C. M., Brotz, L., Purcell, J. E., … Condon, R. H. (2014). Linking human well-being and jellyfish: ecosystem services, impacts, and societal responses. Frontiers in Ecology and the Environment, 12(9), 515-523. doi:10.1890/130298Cegolon, L., Heymann, W., Lange, J., & Mastrangelo, G. (2013). Jellyfish Stings and Their Management: A Review. Marine Drugs, 11(12), 523-550. doi:10.3390/md11020523Hartwick, R. F. (1991). Distributional ecology and behaviour of the early life stages of the box-jellyfish Chironex fleckeri. Hydrobiologia, 216-217(1), 181-188. doi:10.1007/bf00026460Mooney, C. J., & Kingsford, M. J. (2016). The influence of salinity on box jellyfish (Chironex fleckeri, Cubozoa) statolith elemental chemistry. Marine Biology, 163(5). doi:10.1007/s00227-016-2867-1Kingsford, M. J., Seymour, J. E., & O’Callaghan, M. D. (2012). Abundance patterns of cubozoans on and near the Great Barrier Reef. Hydrobiologia, 690(1), 257-268. doi:10.1007/s10750-012-1041-0ACEVEDO, M. J., STRAEHLER-POHL, I., MORANDINI, A. C., STAMPAR, S. N., BENTLAGE, B., MATSUMOTO, G. I., … FUENTES, V. L. (2019). Revision of the genus Carybdea (Cnidaria: Cubozoa: Carybdeidae): clarifying the identity of its type species Carybdea marsupialis. Zootaxa, 4543(4), 515. doi:10.11646/zootaxa.4543.4.3Bordehore, C., Fuentes, V. L., Atienza, D., Barberá, C., Fernandez-Jover, D., Roig, M., … Gili, J. M. (2011). Detection of an unusual presence of the cubozoan Carybdea marsupialis at shallow beaches located near Denia, Spain (south-western Mediterranean). Marine Biodiversity Records, 4. doi:10.1017/s1755267211000650Canepa, A., Fuentes, V., Bosch-Belmar, M., Acevedo, M., Toledo-Guedes, K., Ortiz, A., … Gili, J.-M. (2017). Environmental factors influencing the spatio-temporal distribution of Carybdea marsupialis (Lineo, 1978, Cubozoa) in South-Western Mediterranean coasts. PLOS ONE, 12(7), e0181611. doi:10.1371/journal.pone.0181611Acevedo MJ. Biology, ecology and ecophysiology of the box jellyfish Carybdea marsupialis (Cnidaria: Cubozoa). PhD dissertation. Universitat Politècnica de Catalunya, Barcelona. 2016.Pulis K. A preliminary study of the population, ecology and genetic characters of the Mediterranean box jellyfish (Carybdea marsupialis) in the island of Malta. MSc dissertation. University of Malta, Malta. 2015.Bordehore C. Studies on the ecology of Carybdea marsupialis (Cubozoa) and jellyfish sting risk management. PhD dissertation. Universidad de Alicante, Alicante. 2014.Straehler-Pohl, I., & Jarms, G. (2005). Life cycle of Carybdea marsupialis Linnaeus, 1758 (Cubozoa, Carybdeidae) reveals metamorphosis to be a modified strobilation. 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Washington: American Public Health Association; 2012.Zuur, A. F., Ieno, E. N., Walker, N., Saveliev, A. A., & Smith, G. M. (2009). Mixed effects models and extensions in ecology with R. Statistics for Biology and Health. doi:10.1007/978-0-387-87458-6Zuur, A. F., Ieno, E. N., & Smith, G. M. (2007). Analysing Ecological Data. Statistics for Biology and Health. doi:10.1007/978-0-387-45972-1Yang C, Szu-Pyng K, Fen-Bin L, Pen-Shan H. Twelve different interpolation methods: a case study of Surfer 8.0. ISPRS Congr Istanbul. 2004; 778–783.STRAEHLER-POHL, I., & JARMS, G. (2011). Morphology and life cycle of Carybdea morandinii, sp. nov. (Cnidaria), a cubozoan with zooxanthellae and peculiar polyp anatomy. Zootaxa, 2755(1), 36. doi:10.11646/zootaxa.2755.1.2Chiaverano, L. M., Holland, B. S., Crow, G. L., Blair, L., & Yanagihara, A. A. (2013). Long-Term Fluctuations in Circalunar Beach Aggregations of the Box Jellyfish Alatina moseri in Hawaii, with Links to Environmental Variability. PLoS ONE, 8(10), e77039. doi:10.1371/journal.pone.0077039Hamner, W. M., Gilmer, R. W., & Hamner, P. P. (1982). The physical, chemical, and biological characteristics of a stratified, saline, sulfide lake in Palau1. Limnology and Oceanography, 27(5), 896-909. doi:10.4319/lo.1982.27.5.0896Gordon, M. R., & Seymour, J. E. (2008). Quantifying movement of the tropical Australian cubozoan Chironex fleckeri using acoustic telemetry. Hydrobiologia, 616(1), 87-97. doi:10.1007/s10750-008-9594-7Colin, S. P., Costello, J. H., Katija, K., Seymour, J., & Kiefer, K. (2013). Propulsion in Cubomedusae: Mechanisms and Utility. PLoS ONE, 8(2), e56393. doi:10.1371/journal.pone.0056393Coates, M. M. (2003). Visual Ecology and Functional Morphology of Cubozoa (Cnidaria). Integrative and Comparative Biology, 43(4), 542-548. doi:10.1093/icb/43.4.542Garm, A., O’Connor, M., Parkefelt, L., & Nilsson, D.-E. (2007). Visually guided obstacle avoidance in the box jellyfish Tripedalia cystophora and Chiropsella bronzie. Journal of Experimental Biology, 210(20), 3616-3623. doi:10.1242/jeb.004044Lewin, R. (1986). Supply-Side Ecology. Science, 234(4772), 25-27. doi:10.1126/science.234.4772.25Marcus, N. H., & Marcus, N. H. (1998). Minireview: The importance of benthic-pelagic coupling and the forgotten role of life cycles in coastal aquatic systems. Limnology and Oceanography, 43(5), 763-768. doi:10.4319/lo.1998.43.5.0763Bordehore, C., Fuentes, V. L., Segarra, J. G., Acevedo, M., Canepa, A., & Raventós, J. (2015). Use of an Inverse Method for Time Series to Estimate the Dynamics of and Management Strategies for the Box Jellyfish Carybdea marsupialis. PLOS ONE, 10(9), e0137272. doi:10.1371/journal.pone.013727

Ichthyoplankton composition and variability of a shallow coastal area in the Tabarca Marine Reserve, southeast Iberian Peninsula

We studied the ichthyoplankton assemblage (eggs and larvae) in a shallow coastal area in the Tabarca Marine Reserve (southeast Spain, Mediterranean Sea). Samples were taken during four different months of the same year, covering different temporal scales (season, moon phase, and day-night), and were obtained from two sampling sites, 1 km apart. The temporal variability of catches is discussed, and their relationships with the factors studied. Channel plankton nets were used in order to get the habitat associated assemblage. We captures 21 855 eggs (mean 140.41 eggs/100 m³, SD 260.36) and 4 542 larvae (mean 42.45 larvae/100 m³, SD 82.9). Ninety-nine percent of the larvae were pre-flexion. We identified 20 families. The most abundant taxonomic groups were: Gobiesocidae (31.8 %), Gobiidae (31.7 %), Sardina pilchardus (11.1 %), Bleniidae (7.5 %), Sparidae (6.9 %), Sardinella aurita (2.6 %), Serranidae (2.4 %) and Atherinidae (1.8 %). The resulting assemblage was more similar to that of estuaries and coastal lagoons than coastal shelf areas. The results showed no evidence of retention of commercial species larvae, which may be exported with currents. Analysis showed no difference between both sampling sites. Higher larvae and eggs densities were found in August and June. Eggs variability was associated with the moon phase, i.e., higher catches during the new moon and the first quarter, although there were not differences between day and night. Nocturnal larvae catches were higher, and differences between night and day were more accentuated during dark moon phases.La comunidad de ictioplancton (huevos y larvas) en una zona somera de la reserva marina de Tabarca fue caracterizada a distintas escalas temporales a lo largo de un año (estación, fase lunar y día-noche). Se discute la variabilidad temporal que mostraron las capturas de huevos y larvas, y su posible relación con los factores estudiados. Se utilizaron redes de plancton fijas. Fueron capturados en total 21 855 huevos (media 140,41 individuos/100 m³, SD 260,36) y 4 542 larvas (media 42,45 individuos/100 m³, SD 82,9). Las larvas preflexión constituyeron el 99 % de las capturas. Se identificó un total de 20 familias. Las categorías taxonómicas más abundantes fueron Gobiesocidae (31,8 %), Gobiidae (31,7 %), Sardina pilchardus (11,1 %), Bleniidae (7,5 %), Sparidae (6,9 %), Sardinella aurita (2,6 %), Serranidae (2,4 %) y Atherinidae (1,8 %). La composición de la comunidad se asemejó a la encontrada en estuarios y lagunas costeras por otros autores, más que a la encontrada en zonas de plataforma cercanas. No hay evidencias de que la reserva marina actúe como zona de retención de larvas de especies comerciales, sino más bien de exportación. No hubo diferencias entre las dos localidades de muestreo. Las mayores densidades de huevos y larvas aparecieron en los meses de agosto y junio. Los huevos mostraron cierta variabilidad relacionada con la fase lunar, con mayores capturas en cuarto creciente y luna nueva, pero no tuvieron diferencias día-noche. Las larvas mostraron una mayor densidad durante la noche, con mayores diferencias respecto al día en las fases lunares oscuras.Instituto Español de Oceanografí

Local validation of MODIS sensor sea surface temperature on western Mediterranean shallow waters

Revista oficial de la Asociación Española de Teledetección[EN] The sea surface temperature (SST) estimated from MODIS Aqua products (daytime and nighttime 11 μm and night 4 μm) has been correlated with field data taken at three depths (15, 50, 100 cm) in a Western Mediterranean coastal area. The comparison has allowed us to analyze the uncertainty in the estimation of this parameter in coastal waters using low spatial resolution satellite images. The results show that the daytime SST_11 μm product obtains fittest statistical values: RMSE (root mean square error) and r2 (Pearson’s correlation coefficient) of 1°C and 0.96, respectively, for 50 cm depth.[ES] La temperatura superficial del mar (SST) estimada a partir de los productos 11μm diurnos y nocturnos y 4μm nocturnos del sensor MODIS (Moderate Resolution Imaging Spectroradiometer) a bordo de la plataforma Aqua, han sido comparados con datos medidos in situ a tres profundidades diferentes (15, 50 y 100 cm) en una zona costera del Mediterráneo Occidental. Esta comparación ha permitido analizar la incertidumbre que existe en la estimación de este parámetro en aguas someras y próximas a la costa mediante imágenes de satélite de baja resolución espacial. Los resultados obtenidos demuestran que el producto diurno SST_11 μm, obtiene los estadísticos RMSE (error cuadrático medio) y r2 (coeficiente de correlación de Pearson) más ajustados con valores de 1ºC y 0.96, respectivamente, para la profundidad 50 cm.Los autores agradecen el soporte económico de LIFE+08NAT-CUBOMED (http://www.cubomed.eu) para la adquisición de datos in situ, a la NASA (http://www.nasa.gov) que ha facilitado las imágenes de forma gratuita, y al programa JAE-TEC del CSIC que ha financiado el contrato de Elia Durá. Nuestro agradecimiento a los voluntarios de CUBOMED, especialmente a Neus Figueras, Leticia Vázquez, Vicente Bernabeu y Felipe Escolano, por su valioso trabajo. Agradecemos finalmente al Portet de Dénia (www.elportetdedenia.es), al Real Club Náutico de Dénia (www.cndenia.es) y a la Fundación Baleària (www.balearia.com) por su apoyo.Durá, E.; Mendiguren, G.; Martín, M.; Acevedo-Dudley, M.; Bosch-Bolmar, M.; Fuentes, V.; Bordehore, C. (2014). Validación local de la temperatura superficial del mar del sensor MODIS en aguas someras del Mediterráneo occidental. Revista de Teledetección. (41):59-69. doi:10.4995/raet.2014.2314.SWORD59694

Jellyfish information requests from tourists: Are tourist information offices responding adequately?

5th International Jellyfish Bloom Symposium, 30 May to 3 June 2016, Barcelona.-- 1 pageThe impact of jellyfish on beach tourism has been broadly discussed in the literature. Spain has a large network of municipal Tourist Information Offices (TIO), which offer a general information service for visitors and also respond to ad hoc requests.As part of the LIFE Cubomed project, we found that jellyfish stings account for ~65% of beach lifeguard interventions in the Spanish Mediterranean. We hypothesized that information requests on this topic were being adequately addressed by the TIO, at least as well as other requests.We sent mystery-shopper email requests to all the Spanish Mediterranean (n=224) TIO, asking 6 types of questions about local tourist resources: restaurants, historic routes, museums, beaches, beach services and, finally, jellyfish stings. We assessed the quality of the answers (4-level scale) and response time (days).Our findings showed that response times were similar across all questions (~1.8 days), but that the quality of the responses was higher in the case of “traditional” tourist questions than those concerning jellyfish stings. Indeed, the highest no response (~25%) and low-quality answer rates (~20%) corresponded to the jellyfish question. Some responses even suggested that jellyfish information was the remit of a different department (e.g. environment).These results indicate that training of TIO personnel (staff and managers) is required in the area of jellyfish, as well as improved coordination between the different public services (tourism, lifeguards, environment) in order to provide a better overall response to jellyfish queriesPeer Reviewe

Beach lifeguard intervention data as a tool for detecting jellyfish population trends and jellyfish sting >hot spots>

5th International Jellyfish Bloom Symposium, 30 May to 3 June 2016, Barcelona.-- 1 page, 4 figuresDespite their ecological and socio-economic impact, on tourism, fisheries and aquaculture, for instance, quantitative data on jellyfish abundance in coastal areas is scarce. As part of the LIFE Cubomed project, we explored the usefulness of data on beach lifeguard interventions as a tool for monitoring seasonal trends and spatial distribution of coastal jellyfish.Lifeguard services in the Spanish Mediterranean cover almost all beaches during the tourist season and attend around 200,000 non-severe injuries each year. Jellyfish stings account for around 65% of these interventions. We developed a Sting Index (SI) to determine the seasonal trend of jellyfish stings at different spatial scales and consider it a good indicator of jellyfish abundance. The number of stings is standardized by the sum of injuries (wounds, dislocation, bruising, bone fracture, fainting and sunburn), which are proportional to the amount of people on the beach. We calculated the average SI over 4 years (2010-2013) at some 400 lifeguard stations along the Spanish Mediterranean. SI values ranged between 1.8 and 2.7 and showed no significant trends during this period. This could reflect stable population levels in the area. However, the SI did allow us to detect “hot spots”, where the rate of stings was up to 10 times the average, and we were able to correlate these areas to the presence of certain jellyfish species. This kind of information can be obtained from places where records are kept on jellyfish stings and can help to obtain data on jellyfish at a larger geographical scalePeer Reviewe

Jellyfish prevail among lifeguard assistances at the Spanish Mediterranean beaches. Proposals for improving risk management

Aquatic Sciences Meeting, Aquatic Sciences: Global And Regional Perspectives - North Meets South, 22-27 February 2015, Granada, SpainFew studies have identified the risks in broad coastal areas. A retrospective descriptive study of lifeguard data for 2012 analysed the prevalence of assistance categories along the Spanish Mediterranean coast. The trend in jellyfish stings was examined for 2004-2012. We obtained data form 908 beach lifeguard stations out of 1261 present in the study area. A total of 158377 injuries were reported for 2012. Jellyfish stings (58.1% of the injuries) were the main need for assistance, followed by wounds (14.7%), other marine animals stings (14.2%) and sunburn (3.7%). All sea life-related injuries accounted for 74.1% of the total injuries, followed by musculoskeletal injuries (16.6%) and sun related (4.4%). Among Other Activities, the highest numbers were for rescues at sea (7.9%) and lost child (5.2%). Fatalities for 2012 were 24. The number of jellyfish stings, increased from 2010 to 2012 a 50%. The results showed that Spanish Mediterranean beaches are safe with very low fatalities. Nevertheless, reducing risks needs reliable data on the safety issuesPeer Reviewe

Maintenance, feeding and growth of Carybdea marsupialis (Cnidaria: Cubozoa) in the laboratory

The box jellyfish Carybdea marsupialis has proliferated in some areas of the north-western Mediterranean Sea since July 2008. As for many species, controlled experimentation in the laboratory is needed to improve our knowledge about C. marsupialis, with the ultimate goal of extrapolating the knowledge gained to the marine environment. The aims of this study were to identify the optimal conditions (i.e. aquarium design, environmental parameters and prey type) for the growth and maintenance of this cubomedusa in the laboratory and, additionally, to quantify the feeding rates of the juveniles of this species. We were able to maintain healthy medusae for 140. days. During this time they reached the subadult condition (fact corroborated by observing the gonadal tissue), growing from 2 to 15. mm in diagonal bell width from June to November 2010, respectively. We observed a progressive shift in their preferred dietary composition as the individuals grew. The medusae fed on Artemia salina nauplii along the entire development. Other, larger, prey types (e.g. Mysis sp., Acartia granii copepods and adult Artemia salina) were progressively ingested at the same time as they increased their umbrella size. We also describe the clearance rates, ingestion rates, prey selectivity and digestion times of juvenile C. marsupialis on natural zooplankton and on the copepod Acartia grani. Growth and mortality rates were also calculated. © 2012 Elsevier B.V

Coastal eutrophication may drive the native species Carybdea marsupialis (Cnidaria: cubozoa) to an “invader status” in the Mediterranean

Aquatic Sciences Meeting, Aquatic Sciences: Global And Regional Perspectives - North Meets South, 22-27 February 2015, Granada, SpainNative species can become invaders in their natural habitats as consequence of human alteration of the ecosystem. We have observed a positive correlation between the presence of the cubozoan Carybdea marsupialis along the coast of Denia (NW Mediterranean, Spain) and nutrient concentrations. To elucidate which are the mechanisms behind this relationship, we analyzed data on nutrient concentrations, Chlorophyll a, POM, and microplankton, mesozooplankton and cubomedusae abundance. We also used isotopic signals to trace anthropogenic sources of N and C entering the marine food web. We propose that anthropogenic nutrient inputs scale up the food web and by means of trophic cascades they affect the abundance of jellyfish. Changes in the surrounding Posidonia oceanica meadows, and in the crustacean and polychaete communities associated to them, might be also related with C. marsupialis proliferations. Overall, the outbreaks of the species recorded along the Spanish Mediterranean coast coincide with urban areas, riverine discharges and harboursPeer Reviewe

Environmental factors influencing the spatio-temporal distribution of Carybdea marsupialis (Lineo, 1978, Cubozoa) in South-Western Mediterranean coasts

Jellyfish blooms cause important ecological and socio-economic problems. Among jellyfish, cubozoans are infamous for their painful, sometimes deadly, stings and are a major public concern in tropical to subtropical areas; however, there is little information about the possible causes of their outbreaks. After a bloom of the cubomedusa Carybdea marsupialis (Car-ybdeidae) along the coast of Denia (SW Mediterranean, Spain) in 2008 with negative consequences for local tourism, the necessity to understand the ecological restrictions on medusae abundance was evident. Here we use different models (GAM and zero-inflated models) to understand the environmental and human related factors influencing the abundance and distribution of C. marsupialis along the coast of Denia. Selected variables differed among medusae size classes, showing different environmental restriction associated to the developmental stages of the species. Variables implicated with dispersion (e.g. wind and current) affected mostly small and medium size classes. Sea surface temperature, salinity and proxies of primary production (chl a, phosphates, nitrates) were related to the abundances of small and large size classes, highlighting the roles of springtime salinity changes and increased primary production that may promote and maintain high densities of this species. The increased primary (and secondary) production due to anthropogenic impact is implicated as the factor enabling high numbers of C. marsupialis to thrive. Recommendations for monitoring blooms of this species along the study area and applicable to Mediterranean Sea include focus effort in coastal waters where productivity have been enriched by anthropogenic activities