43 research outputs found

    Prvi nalaz novorođene jedinke morskog psa prasca Oxynotus centrina u istočnom Jadranskom moru

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    Many biological aspects of deep-water sharks are poorly known due to their rarity and difficulties in conducting detailed research on them. The angular roughshark (Oxynotus centrina) is a rare species, critically endangered in the Mediterranean Sea, of which records are scarce across this region. Here we present a record of a female neonate O. centrina from the south-eastern Adriatic Sea, caught by a Montenegrin commercial trawler. Scientific observers were present on-board and collected the specimen, which was subsequently analysed in the laboratory. The specimen was 225 mm long (TL), weighed 59.6 g and had an unhealed umbilical scar. To date, records of this species in the Adriatic Sea have comprised of both adult and older juvenile individuals, but no records of neonates were found in the published literature. In this work, the basic biological observations of the specimen are reported.Mnogi biološki aspekti dubokomorskih morskih pasa slabo su poznati zbog rijetkih nalaza te nedostatka detaljnijih istraživanja. Morski pas prasac (Oxynotus centrina) je rijetka i kritično ugrožena vrsta u Sredozemnom moru, a nalazi ove vrste na tom području su oskudni. U ovom radu se prikazuje nalaz novorođene ženke O. centrina iz jugoistočnog područja Jadranskog mora, uhvaćene od strane crnogorskog komercijalnog ribarskog broda. Jedinka je prikupljena od strane znanstvenih promatrača koji su bili na brodu u trenutku ulova, te je naknadno analizirana u laboratoriju. Jedinka je bila duga 225 mm (TL), težila je 59,6 g i imala je vidljiv nezarasli pupčani ožiljak. Dosadašnji nalazi ove vrste u Jadranskom moru uključivali su samo odrasle i starije juvenilne jedinke, dok nalazi novorođenih jedinki do sada nisu dokumentirani. U ovom radu su prikazana osnovna biološka zapažanja o analiziranoj jedinci

    Morfometrijske mjere mlađi psa modrulja Prionace glauca (Linnaeus, 1758) i karakteristike potencijalnih lokaliteta za njegov mrijest u obalnim vodama Crne Gore (jugoistočni Jadran)

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    The blue shark belongs to the group of the most widespread pelagic sharks in the world. It inhabits the pelagic zone of almost all warm and temperate seas and oceans. As it is one of the most abundant shark species, it is frequently caught in different types of fishing gear operated in the pelagic zone. This study provides the first data on the reproduction of this species in Montenegrin waters (in the Southeastern Adriatic Sea). Six newborn blue sharks were found during our field excursions. For three of them, detailed morphometric measurements are presented. Alongside the newborns, a gravid female was also recorded. The data was collected in the period from April to October 2017. According to the published literature and the data presented in this paper, species reproduction is likely to be seasonal. A review of the areas where the specimens were recorded was carried out in order to infer if the adult females choose them specifically as their parturition grounds.Pas modrulj pripada grupi najviše rasprostranjenih pelagičnih morskih pasa na svijetu. Obitava u pelagičnoj zoni gotovo svih umjerenih i toplih mora i oceana. Premda je jedan od najčešćih morskih pasa, često se lovi različitim ribolovnim alatima koji se koriste u pelagijalu. Ovim istraživanjem sakupljeni su prvi podaci o reprodukciji ove vrste u Crnoj Gori (Jugoistočni Jadran). Tijekom terenskih istraživanja, evidentirano je šest tek rođenih jedinki. Za tri jedinke, prikazane su detaljne morfo-metrijske mjere. Pored spomenutih jedinki, zabilježena je i gravidna ženka ove vrste. Svi podaci su sakupljeni u razdoblju od travnja do listopada 2017. Prema do sada objavljenoj literaturi i ovdje prikazanim podacima, moguće je da je reprodukcija ove vrste sezonska. Izvršen je i pregled lokaliteta na kojima su jedinke pronađene, kako bi se utvrdilo biraju li ih ženke kao mjesta za rađanje mladih

    ENSIGN WASPS OF SERBIA AND MONTENEGRO (HYMENOPTERA: EVANIOIDEA: EVANIIDAE)

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    This paper presents the first report on ensign wasp fauna in two central Balkan countries, Serbia and Montenegro. We established the presence of three species  (out of five recorded in Europe): Brachygaster minutus, Prosevania fuscipes and Zeuxevania splendidula, the last based on an old literature report. We briefly discuss the patterns of their distribution and occurrence, in relation to their specific bionomy and the collecting techniques applied

    Observations of juvenile sandbar sharks Carcharhinus plumbeus (Nardo, 1827) around the Bojana River delta (Southern Adriatic Sea)

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    The sandbar shark (Carcharhinus plumbeus) is considered rare in the Adriatic Sea and the majority of records originate from the northern Adriatic, where a nursery area for this species close to the Po delta system has been repeatedly proposed. This study provides 5 new records and analyses the previously published records of sandbar sharks recorded around the delta of the River Bojana (in Montenegro, in the south-eastern Adriatic). The River Bojana located on the border between Montenegro and Albania, is the second largest river flowing into the Adriatic Sea, where it forms a highly productive ecosystem already known as a local hotspot for smooth-hound sharks (Mustelus spp.). New records of sandbar sharks have emerged as a result of citizen science (a social media survey) and direct reports from fishermen. The total length of C. plumbeus juveniles ranged from approximately 800 mm to 1100 mm, and most (n=5) were caught by set gillnets. The data presented here show that juveniles are consistently present around the estuary and indicate the importance of this fragile estuarine ecosystem for sandbar sharks. Additionally, this study also provides morphometric data collected from a single individual

    Nove vrste riba i rakova u Crnogorskim vodama (južni Jadran)

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    The structure and composition of Mediterranean biodiversity has changed significantly. So far, in Montenegrin coastal waters, nine new non-native species have been recorded: Tylosurus acus imperialis, Caranx crysos, Siganus luridus, Fistularia commersonii, Stephanolepis diaspros, Sphoeroides pachygaster, Lagocephalus sceleratus, Callinectes sapidus and Farfantepanaeus aztecus. Allochthonous species are starting to compete for food and space and leading to habitat degradation, socio-economic impacts and can hybridise with the native species. Natural factors and human activities have enabled the arrival of non-native species into the Adriatic Sea. Four of the species are Lessepsian immigrants, which arrived via the Suez Canal, but five others were introduced from the Atlantic Ocean, through the Strait of Gibraltar. Analysis using the Marine Fish Invasiveness Screening Kit (MFISK), Aquatic Invasiveness Screening Kit (AS-ISK) and Receiver operating characteristic (ROC) showed a calibration threshold of 22.5 for MFISK, a BRA (Basic Risk Assessment) score of 34 and a CCA (Climate Change Assessment) score of 46. A measure of the accuracy of the calibration analysis is the area under the ROC curve (AUC). Two species were characterised as non-invasive: Tylosurus acus imperialis and Caranx crysos, but five others were characterised as invasive and covered by the categories from moderate to high-risk.Struktura i sastav bioraznolikosti Sredozemlja značajno su se promijenili. Do sada je u crnogor- skom primorju zabilježeno devet novih ne-nativnih vrsta: Tylosurus acus imperialis, Caranx crysos, Siganus luridus, Fistularia commersonii, Stephanolepis diaspros, Sphoeroides pachygaster, Lagocephalus sceleratus, Callinectes sapidus i Farfantepanaeus aztecus. Alohtone vrste počinju se natjecati za hranu i prostor i dovode do degradacije staništa, socio-ekonomskih učinaka i mogu hibridizirati s autohtonim vrstama. Prirodni čimbenici i ljudske aktivnosti omogućili su dolazak ne- nativnih vrsta u Jadransko more. Četiri vrste su lesepsijski imigranti, koji su stigli preko Sueskog kanala, ali pet drugih uneseno je iz Atlantskog oceana, kroz Gibraltarski tjesnac. Analiza korištenjem programa MFISK (Marine Fish Invasiveness Screening Kit), AS-ISK (Aquatic Invasiveness Screen- ing Kit) i ROC (Receiver operating characteristic) pokazala je prag kalibracije od 22,5 za MFISK, BRA (Basic Risk Assessment)) rezultat od 34 i CCA (Climate Change Assessment) ocjenu od 46. Mjera točnosti kalibracijske analize je površina ispod ROC krivulje (AUC). Dvije vrste okarakter- izirane su kao neinvazivne: Tylosurus acus imperialis i Caranx crysos, no pet drugih okarakter- izirano je kao invazivno i obuhvaćeno kategorijama od umjerenog do visokog rizika

    Effect of thermal stress of short duration on the red blood cell parameters of Barbus balcanicus Kotlik, Tsigenopulos, Rab, Berrebi, 2002

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    In this study, red blood cell parameters of Barbus balcanicus Kotlik, Tsigenopulos, Rab, Berrebi, 2002 subjected to acute thermal stress were investigated. Fish were caught by electro fishing in the Suturlija river, a small tributary of the river Vrbas (N latitude 44˚44' 38˝, E longitude 17˚ 09' 10˝) in summer (July) and transported to the laboratory. Fish were randomly distributed in four aquaria of 30 L each. In all the four aquaria, the water temperature was continuously kept at 19°C by appropriate devices. After period of adaptation (three weeks), half of the fish (24) were used as a control group while the other 24 were subjected to thermal stress by raising the water temperature to 29°C (10°C increase) in 60 min. In both control and thermally treated, fish blood was collected by heart puncture according to “Animal welfare act“. Analyses were performed with native blood, without addition of any anticoagulant and the values of red blood cell count (RBC), haemoglobin concentration, packed cell volume (PCV), Corpuscular Volume (MCV), Mean Corpuscular Haemoglobin (MCH) and Mean Corpuscular Haemoglobin Concentration (MCHC) were determined. In the thermally treated fish, the values of PCV and MCV increased (p = 0.0003 and p = 0.0147 respectively), and those of MCHC decreased substantially (p = 0.0001).Keywords: Haematology, temperature, Barbus balcanicusAfrican Journal of Biotechnology Vol. 12(18), pp. 2484-249

    Neobična pojava jaja inćuna (Engraulis encrasicolus, Linnaeus 1758) u prosincu 2006. godine u Bokokotorskom zaljevu (Jadransko more)

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    Five anchovy (Engraulis encrasicolus, Linnaeus 1758) eggs were caught during an ichthyoplankton survey in Boka Kotorska Bay (south Adriatic Sea) with a PairOVET (modified CalVet) plankton net on December 5th, 2006. Eggs were found at two sampling stations (42°28’30.24” N, 18°44’41.81” E and 42°29’30.23” N, 18°40’41.84” E). It is the third record of anchovy eggs in the winter months in the Adriatic Sea.Pet jaja brgljuna (Engraulis encrasicolus, Linnaeus 1758) su uhvaćena tijekom istraživanja ihtioplanktona u Bokokotorskom zaljevu (južni Jadran) s PairOVET (izmijenjeni CalVet) i planktonskom mrežom 5. prosinca 2006. godine. Jaja su pronađena na dva mjesta uzorkovanja (42 ° 28’30 .24 “N, 18 ° 44’41 0,81” E i 42 ° 29’30 0,23 “N, 18 ° 40’41 0,84” E). Ovo je treći nalaz jaja brgljuna u zimskim mjesecima u Jadranu

    STATUS OF THE POTENTIALLY INVASIVE ASIAN SPECIES SCELIPHRON DEFORME IN EUROPE, AND AN UPDATE ON THE DISTRIBUTION OF S. CURVATUM (HYMENOPTERA: SPHECIDAE)

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    We reviewed the distribution of the two Asian species of the genus Sceliphron Klug, introduced into Europe in the late 1970s to early 1980s: S. (Hensenia) curvatum (Smith) and S. (Hensenia) deforme (Smith). Both species are routinely considered as invasive in Europe, but the status and effects of their (eventual) invasiveness are yet to be documented and evaluated. We had a focus on two areas, the Balkan Peninsula and European Russia, based principally on the study of specimens collected over the last 15 years, but we also reviewed the extensive published evidence (including some very important internet-based records), and for S. curvatum we provided a concise overview of the entire European range. We confirmed that the latter recorded species, S. deforme, has been introduced into Europe at least twice, first in the central part of European Russia, and then in the SW Balkans, and we established that these introductions originated from different source populations, belonging to a geographically widely separated Asian subspecies. Based on the most recent evidence, we confirmed successful establishment of S. deforme in both areas, and documented its ongoing spreading: from central European Russia southwards/southeastwards, and most probably from the Balkans eastwards. We rectified several erroneous country records for S. deforme (France, Italy, Bulgaria, Greece, “central Europe”), which have been extensively perpetuated in several important publications about the invasive species in Europe in the last three years (n.b. – for Greece, we have positively documented its presence only now). For S. curvatum, we added a new country record (Georgia/Abkhazia), and provided a few important earlier records from the Balkans (Serbia, Greece, Croatia, Bulgaria), which shift the timing of the previously published “first appearance” dates in the area (for two years for N Serbia and C Greece), or otherwise modify the knowledge of its history of spread. Since the most recent evidence suggests the rapid eastward advancing of both introduced species towards their respective westernmost/northernmost native range limits in western to central Asia, we considered it important to briefly review the state of knowledge about their possible coexistence in that area. We also provided detailed maps of their allochtonous ranges in Europe (currently exceeding the longitudinal span of 4,000 km) and westernmost part of their native ranges in Asia. Finally, we very briefly commented on some ecological aspects of their existence within the allochtonous range (parasitism, sex ratio, phenology)

    FURTHER RANGE EXPANSION OF THE SCULPTURED RESIN BEE (MEGACHILE SCULPTURALIS) IN SERBIA AND BOSNIA & HERZEGOVINA

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    Megachile sculpturalis is the first non-native bee species established in Europe, originating from E-Asia. Since early detections in SW-Europe (2008–2010) its spreading resulted in a range currently spanning nearly 2,800 km x 1,100 km across the southern and central Europe. In SE-Europe establishment was confirmed since 2015 in NE-Hungary, followed by detection in N-Serbia (2017), and wider spreading across the eastern Pannonian Plain (2018–2019); eventually it was detected in NW-Bosnia & Herzegovina (2020). Accordingly, the repeated calls for monitoring of M. sculpturalis spread were voiced, aiming to address its potential invasiveness, but mostly lacking a more specific assessment protocol. A 'working concept' for a comprehensive monitoring of M. sculpturalis was proposed within the survey conducted in Belgrade (Serbia) during 2017–2019, based on quantitative assessment of bee population trends in relation to focal plant resources. There was a need to improve and broaden this initial framework, e.g., to allow for different spatio-temporal scales and various potential usage requirements. Therefore, in 2020 we considerably extended the research scope, defined at two spatial scales: LOCAL, for the Belgrade area – the continuation of protocol development, through a high-intensity assessment of M. sculpturalis abundance, bionomics, and distribution, in parallel with assessment of extended set of relevant plants (and potential bee-plant interactions); REGIONAL, a survey covering the bee spreading across Serbia and Bosnia & Herzegovina, aiming to provide a reference time-section in expanding SE-European front, while also extending the knowledge of its environmental affinities. The study included the launching of a pioneering citizen science project, which enabled a remarkable geographic coverage despite modest return of positive reports. The Belgrade-scale survey yielded a modest increase in recorded locations, relative to 2019, but the recording efficiency was decreased, despite a much intensified surveying efforts and extended coverage. This corroborated the importance of inter-seasonal variation of key food resources, which affects both the population dynamics and detectability of this bee, through alternating concentration and dilution effects. We confirmed the strong association of detection success with availability and variability of blooming Styphnolobium, at both scales, indicating the highest relevance of inclusion of this plant into monitoring assessment protocols. The established phenological extent of M. sculpturalis activity (>70 days) also closely corresponded with the phenology of Styphnolobium blooming; yet it does not represent the entire phenological span for the region. Almost no record came from surveying other plants. The regional expansion of M. sculpturalis during 2017–2020 is documented from 19 wider locations (16 added in 2020). It is particularly well established in the Pannonian, and to a lesser extent in peri-Pannonian area of Serbia and B&H, while the approximated range extent was likely doubled during 2019–2020. Further south records were scarce, indicating the slower expansion across the hilly-mountainous part of the Balkans. Records largely came from urban or other settlements, only about a third from semi-natural or agricultural environments

    Dnevni naraštajni prstenovi u otolitima i stopa rasta juvenilnog inćuna, Engraulis encrasicolus (Linnaeus, 1758), u jugoistočnom Jadranu

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    Daily growth rate of juvenile anchovy, Engraulis encrasicolus (Linnaeus, 1758), was estimated in the south-eastern Adriatic Sea. Samples were taken by a commercial beach seine net and the size range of 100 sampled individuals was 5.0-6.8 cm total length. Age was estimated by counting growth increments of sagittal otoliths, which are formed with daily periodicity. Estimated ages were 41- 90 days and hatch date for each age class was back-calculated from the date of capture. The calculated instantaneous growth rate was 0.41 mm day-1. Fish size at metamorphosis from late larva to juvenile was estimated to 3.2 cm total length. Parameters of the von Bertalanffy’s growth function were L∞ = 10.41 and K = 3.36Dnevna stopa rasta juvenilnog inćuna, Engraulis encrasicolus (linnaeus, 1758), procijenjena je u jugoistočnom Jadranu. Uzorci su sakupljani komercijalnom obalnom mrežom potegačom, a raspon veličine kod 100 uzorkovanih jedinki iznosio je 5.0-6.8 cm ukupne dužine. dob je procijenjena brojenjem dnevnih naraštajnih prstenova na sagitalnim otolitima. Procijenjena starost kolebala je između 41- 90 dana, a nadnevak izvaljivanja ličinke za svaki starosni razred bio je naknadno izračunat prema datumu ulova. Izračunata trenutna stopa rasta iznosila je 0.41 mm dan -1. Veličina ribe za vrijeme metarmofoze iz kasnog stadija ličinke u juvenilni stadij procijenjena je na 3.2 cm ukupne dužine. Parametri u von Bertalanffy-jevoj jednadžbi rasta bili su L∞ = 10.41 i K = 3.36
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