This study reports exceptional penetrations of the Sharpchin Barracudina Paralepis coregonoides into pelagic, open-sea sediment traps in the Levant Basin of the SE Mediterranean Sea. This first substantiated record of the species at the Levant Basin has been observed in two sediment traps at 180 and 280 m depth, 50 km offshore the coast of Israel. Over one year of deployment (November 2016 till November 2017), 483 adult individuals have been repeatedly entrapped inside the automatic sediment traps that were covered with a 25 mm baffler mesh for the first half year and then replaced with a smaller 10 mm mesh for the second half. This undesirable catch of such an elusive and understudied species enabled us to revise its distribution, abundance and genetic divergence. The continuous entrapment throughout the year of sexually mature individuals has confirmed that this species is common to the SE Mediterranean. In order to avoid unwanted entrapments that disrupt biogeochemical sediment studies, the installation of small mesh size nets on the conventional sediment trap openings must be considered in the pelagic zone of the SE Mediterranean, and probably elsewhere.
Bibliographical noteFunding Information:
We thank the Mediterranean Sea Research Center of Israel (MERCI) for its partial support in establishing and running the DeepLev station. We also thank the North American Friends of Israel Oceanographic and Limnological Research (IOLR) and Wolfson Foundation via Bar Ilan University (BIU) for their financial support. We thank the IOLR electronic, sea operations and marine physical departments for invaluable help with facilities and technical operations in establishing and running the DeepLev station. We thank the engineers of the machine shop at BIU for their help in the buildup of mooring and attached devices. This project was partly funded by the Israel Science Foundation grant ISF 25/2014. We thank the Israeli Ministries of Energy and Environmental Protection for their support in related activities in frame of the National Monitoring Program for Israeli Mediterranean Waters. We also thank the captain and crew of the R/V 'Bat Galim' for their assistance.
of sexually mature individuals, this clearly indicates that this species is a common resident at the Levant Basin. We thank the MediterraneSaena Research Center of Acting as a fish aggregating device (Castro et al., Israel (MERCI) for its partial support in establishing and 2002; Dempster & Taquet, 2004), the sediment traps riunn ning theD eepLevs tation.W e also thankthe North our study have most likely attracted local residents of American Friends of Israel Oceanographic and Limno-the mesopelagic habitat. Howev, ecronsidering size-relogical Research (IOLR) and WolfsonFoundation via striction and opening orientation of the traps, only ver-Bar Ilan University (BIU) for their financial support. We tical swimmers can ensure capture. Indeed, this unique thank the IOLR electronic, sea operations and marine habit of swimming characterizes species of barracudina physical departments for invaluable help with facilities (Whitehead et al.,1984), which explains, together with and technical operations in establishing and running the their slender form, this mono-species entrapment events. DeepLev station. We thank the engineers of the machine We postulate that this unique swimming behavior con-shop at BIU for their help in the buildup of mooring and tributes to their known tendency to efficiently avoid sam-attached devices. This project was partly funded by the pling nets, which is eventually reflected in a scarce and Israel Science Foundation grant ISF 25/2014. We thank infrequent information available throughout their distri-the Israeli Ministries of Energy and Environmental Pro-bution, that is mainly based on documenting juvenile and tection for their support in related activities in frame of adult specimens inside stomachs of large pelagic fishes the National Monitoring Program for Israeli Mediterra-(Potier et al., 2007; Consoli et al., 2008; Battaglia et al., nean Waters.We alsothankt he captain and crew of the 2013). Moreov,e trhe absence of juvenindividuals in ile R/V‘Bat Galim’for their assistance. the traps throughout the year may suggest they either lack vertical swimming abilities at this life stage or that they simply do not dwell in this layer of the pelagic water col-References umn. Although this study only summarizes a single ye,a r Armstrong, R.A., Lee, C., Hedges, J.I., Honjo, S., Wakeham, higher values in average catchper collecting bottle were S.G., 2002. Anew, mechanistimc odelf or ograniccarbon shown during the colder months, though without correla-fluxes in the ocean based on the quantitative association of tion with 300 m water temperature measurements (Fig. POC with ballast minerals. Deep-Sea Resecahr Part II49, 2). This result may coincide with the general trend in 219-236. which temperate or cold water species avoid war,m wBaatttearglia,P .,Andaloro,.F, Consoli,.,PEspositoV,., Malara, and perform vertical or horizontal migration when local D. et al., 2013. Feeding habits of the Atlantic bluefin tuna, conditions are inadequate (Stern et al., 2018). Thunnus thynnus (L. 1758), in the central Mediterranean The shallow mitochondrial genetic divergence found Sea (Strait of Messina). Helgoland Marine Rescehar67, between specimens from this study and previously pub-97-107. lished data from distant localities around the Atlantic Buessele,rK.O.,Antia,A .N., Chen, M., Fow,lSe.rW., Gardne,r Ocean (0.2-0.8%) signifies the pelagic lifestyle of this W.D. et al., 2007. An assessment of the use of sediment species and could possibly represent migration charac-traps for estimating upper ocean particle fluxes. Journal of teristics and/or efficient propagule dispersal that enables Marine Research, 65 (3), 345-416. continual gene flow throughout its distribution. Castro, J.J., Santiago, J.A., Santana-Ortega, A.T., 2002A. gen- Last, apart from this unplanned contribution to meso-eral theory on fish aggregation to floating objects: an al- pelagic ichthyolog,y we considethis r case as a ‘warning ternative to the meeting point hypothesis. Reviews in Fish sign’ for future deployment of pelagic sediment traps. Biology and Fisheries 11, 255-277. This general trend of uninvited “swimmers” in sediment Consoli, P., RomeoT,., BattagliaP,., CastriotaL, ., Esposito, V. traps has been previously debated, providing several rec-et al., 2008. Feeding habits of the albacore tuna Thunnus ommendations on how to prevent, remove or consider alalunga (Perciformes, Scombridae) from central Mediter-the impact of the different life forms of these swimmers ranean Sea. Marine Biology 155, 13-120. (Buesseler et al., 2007). In our case, the fish penetrations Dempste,rT., Taquet, M., 2004. Fish aggregadtieovnice( FAD) made it impossible to quantify and intelligibly analyze research: gaps in current knowledge and future directions the sediment particles and their fluxes, and only after for ecological studies. Reviews in Fish Biology and Fish- placing a 7mm stainless-steel mesh on the trap openings eries 14, 21-42. during the third deployment, were we able to prevent fu-Fricke,R.,Eschme,yWer.,vanderLaan,R.,2018.Catalogo-ffish ture additional fish entries. es: genera, species, references. California Academy of Scienc- Conflict of Inteerst: The authors decel atrhat they es, San Francisco, CA, USA http://ersearcharchive.calacad-e have no conflict of inetsetr. my.org/research/ichthyology/catalog/fishcatmain.asp
© 2019 Mediterranean Marine Science.
- Genetic divergence
- Mediterranean sea
- Mesopelagic fishes
- Mooring station
ASJC Scopus subject areas
- Environmental Engineering
- Ecology, Evolution, Behavior and Systematics
- Aquatic Science