The presence of non-reproductive Atlantic bluefin tuna Thunnus thynnus females in the Mediterranean Sea was investigated through histological analysis of the gonads. Three hundred and twenty-six ovary samples were collected from adults captured at different locations in the Mediterranean Sea during the reproductive seasons between 1998 and 2008. Only three specimens were considered to be in a non-reproductive state: two of them were in a reabsorbing state showing ovaries with early vitellogenic oocytes and extensive alpha and beta atresia of vitellogenic follicles; the third showed gonads with perinucleolar oocytes and was considered to be in a resting state. The low occurrence of non-reproductive individuals found in this study makes it unlikely that non-reproductive individuals aggregate with reproductive ones during their migration towards spawning grounds. Further research is suggested in order to investigate the potential presence of non-reproductive individuals on non-spawning grounds during the reproductive season.
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http://dx.doi.org/10.1111/j.1095-8649.2009.02355.x | DOI Listing |
Sci Total Environ
January 2025
Department of Physical, Earth and Environmental Sciences, University of Siena, Italy; NBFC, National Biodiversity Future Center, Palermo, Italy.
The Mediterranean basin is the second largest global biodiversity hotspot in the world, which coexists with a plethora of anthropogenic stress. This study examines the risks that marine litter poses to Mediterranean biodiversity, using the Special Protection Area of Mediterranean Importance (SPAMI) "Pelagos Sanctuary" as a case study. In this paper, a new survey method and data analysis strategies to assess the impact of marine litter, including microplastics, on Mediterranean organisms, is proposed.
View Article and Find Full Text PDFNaturwissenschaften
January 2025
Sea Turtle Research and Application Center, Çanakkale Onsekiz Mart University, Çanakkale, Türkiye.
Information on the age of vertebrate species such as sea turtles is crucial for planning management and conservation actions. The age of sea turtles has been estimated by skeletochronological analysis using skeletal growth marks in different bones. This study focused on the consistency of the number of visible lines of arrested growth (LAG) observed from the humerus and phalanx bone used for age estimation in Chelonia mydas and Caretta caretta.
View Article and Find Full Text PDFRSC Adv
January 2025
Department of Physical Sciences, School of Arts and Sciences, Lebanese American University Beirut 1102-2801 Lebanon +961 1 786456, ext. 3950.
The Mediterranean Sea is an intercontinental marine environment renowned for its biodiversity and ecological significance. However, it is also one of the most polluted seas globally with significant levels of microplastics and heavy metals among other emerging contaminants. In Lebanon, inadequate waste management infrastructure and unregulated industrial discharges have exacerbated water quality deterioration by introducing these complex contaminants into surface and seawater.
View Article and Find Full Text PDFEnviron Microbiol Rep
February 2025
Faculty of Engineering, Department of Chemistry, Istanbul University-Cerrahpaşa, Istanbul, Türkiye.
Marine mucilage disasters, primarily caused by global warming and marine pollution, threaten food security and the sustainability of marine food resources. This study assessed the microbial risks to public health in common sole, deep-water rose shrimp, European anchovy, Atlantic horse mackerel and Mediterranean mussel following the mucilage disaster in the Sea of Marmara in 2021. The total viable count, total Enterobacteriaceae count and the presence of Escherichia coli O157:H7, Salmonella spp.
View Article and Find Full Text PDFEnviron Toxicol Chem
January 2025
Norwegian Institute for Nature Research, Oslo, NO-0855 Norway.
This study examines how southern wintering areas may contribute to organochlorine (OCs) loads in arctic seabirds during breeding. Light-sensitive geolocators (GLS loggers) were deployed on Arctic skuas (Stercorarius parasiticus) in one high arctic and two subarctic colonies. Hexcahlorobenzene (HCB), Chlordanes, Mirex, p, p'-dichlorodiphenyldichloro- ethylene (p, p'-DDE), and Polychlorinated biphenyls (PCBs) were measured in the blood of breeding adults at the nest (58 individuals, a total of 128 samples) in northern Norway and Svalbard between 2009 and 2015.
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