Novi podaci o pojavljivanju kritično ugroženog sklata sivca Squatina squatina u hrvatskom dijelu Jadrana

Two out of three critically endangered species of angelsharks (genus Squatina (Dumeril, 1806)) inhabiting the Mediterranean have been recorded in the Adriatic Sea, namely smoothback angelshark S. oculata Bonaparte, 1840 and common angelshark S. squatina (Linnaeus, 1758). While S. oculata has been extirpated from the Adriatic Sea due to overfishing, the presence of S. squatina remained questionable and some authors propose the species is regionally extinct since the 1980s. We present new data on the occurrence of S. squatina in the Croatian Adriatic Sea based upon inspection of collections from natural history museums and literature sources as well as three new records resulting from bycatch in commercial bottom trawls in 2016 and 2017. A low overall number of records and the complete absence of the species in scientific trawl surveys conducted since 1958, indicate its low abundance and question the effectiveness of scientific surveying in detecting rare species. Our analysis showed that this formerly abundant species is still present in the Adriatic Sea, emphasizing the importance of implementing novel approaches, such as citizen-science programmes, in studying its current distribution. Although the legal framework for angelshark conservation already exists, poor implementation and lack of any species-specific conservation measures will most probably result in further population declines and extinction of S. squatina from the Adriatic Sea.U Jadranu su zabilježene dvije od tri kritično ugrožene vrste sklatova koje žive u Sredozemnom moru (rod Squatina (Dumeril, 1806)), sklat žutan S. oculata Bonaparte, 1840 i sklat sivac S. squatina (Linnaeus, 1758). Dok je S. oculata nestala iz Jadrana zbog prevelikog izlova, prisutnost vrste S. squatina je upitna i neki autori predlažu da se vrsta proglasi regionalno izumrlom od 1980. godine. U radu donosimo nove podatke o pojavljivanju vrste S. squatina u hrvatskom dijelu Jadrana na temelju pregleda zbirki prirodoslovnih muzeja i literaturnih izvora te tri nova nalaza kao posljedice slučajnog ulova komercijalnim pridnenim koćaricama iz 2016 i 2017. Ukupni mali broj nalaza i potpuna odsutnost vrste u znanstvenim istraživanjima koćarenjem od 1958. ukazuju na njenu nisku brojnost i na upitni učinak znanstvenih istraživanja u pronalasku rijetkih vrsta. Naša analiza pokazuje da je ova nekad brojna vrsta još uvijek prisutna u Jadranu, uz naglasak na važnost primjene novih metoda za utvrđivanje njene trenutne rasprostranjenosti kao što su programi znanosti za građane. Iako pravni okvir za zaštitu sklata već postoji, njeno loše provođenje i nepostojanje bilo kakvih mjera zaštite specifičnih za tu vrstu vjerojatno će rezultirati daljnjim padom brojnosti populacije i izumiranjem sklata sivca u Jadranu

Helianthemum jonium (Cistaceae), nova vrsta u istočnom Jadranu

The occurrence of Helianthemum jonium Lacaita & Grosser ex Bég. in Fiori & Bég. (Cistacaeae) is reported and documented here for the first time in Croatia and Montenegro, and it is confirmed in the Albanian flora after 80 years. The species grows on sandy soils within maquis and garrigue communities in four Adriatic islands: Vis, Biševo, Hvar and Lopud, and within psammophilous vegetation near Ulcinj in Montenegro and in Hamallaj, north of Durrës in Albania. The morphological relationship with the allied H. leptophyllum Dunal and H. apenninum (L.) Mill. is here briefly discussed. Remarks about its taxonomy, lectotypification, habitat and ecology in the Adriatic region are also provided. The species H. jonium was previously known only from the Apennine Peninsula; hence these new eastern Adriatic records extend its distribution area to the east, and it can therefore be considered an amphi-Adriatic endemic element.Prisutnost vrste Helianthemum jonium Lacaita & Grosser ex Bég. in Fiori & Bég. (Cistacaeae) je ovdje po prvi puta zabilježena i dokumentirana u flori Hrvatske i Crne Gore te potvrđena u flori Albanije nakon 80 godina. Vrsta raste na pješčanim tlima unutar vegetacije makije i gariga na četiri jadranska otoka: Vis, Biševo, Hvar i Lopud te unutar psamofilne vegetacije kod Ulcinja u Crnoj Gori i Hamallaju, sjeverno od Drača u Albaniji. Morfološka sličnost sa srodnim vrstama, H. leptophyllum Dunal i H. apenninum (L.) Mill. je ovdje ukratko diskutirana. Također se daju napomene o njezinoj morfologiji, lektotipifikaciji, staništu i ekologiji u Jadranskom području. Vrsta H. jonium prethodno je bila poznata jedino s Apeninskog poluotoka, a nova nalazišta u istočnom Jadranu pridonose istočnom proširenju granice areala vrste te se ista mora smatrati amfi-jadranskim endemičnim elementom

Analiza ishrane zelene želve, Chelonia mydas, iz Jadranskog mora

The green sea turtle (Chelonia mydas) is a foraging specialist, with strong tendency towards herbivory of neritic-stage individuals. Due to lack of data on the feeding ecology of this species in the Mediterranean, we analysed diet composition of one juvenile green turtle with the curved carapace length of 40.0 cm, found dead in the eastern Adriatic Sea (Croatia) in December 2001. The turtle has dominantly feed upon benthic polychaetes Chaetopterus variopedatus (69.8%), while seagrass (Cymodocea nodosa) and algae accounted for 11.1% of the total wet mass. Species composition and their vertical distribution showed that the turtle was in the post-pelagic stage and has foraged in the shallow coastal waters. We discuss our results in the light of recent recoveries of C. mydas juveniles in Albania and Greece, and suggest the existence of an Ionian-Adriatic developmental pathway of green turtles from reproductive habitats in the eastern Mediterranean Sea.Zelena želva (Chelonia mydas) je specijalist u ishrani, sa snažnom tendencijom neritičkih stadija prema herbivornosti. Zbog potpunog nedostatka podataka o ekologije ishrane ove vrste u Sredozemlju, proveli smo analizu sadržaja probavila jedne zelene želve zakrivljene dužine karapaksa 40 cm, na|ene uginule u istočnom Jadranu (Hrvatska) u prosincu 2001. Dominantan plijen predstavljao je pridneni mnogočetinaš Chaetopterus variopedatus (69.8%), dok su morske cvjetnice (Cymodocea nodosa) i alge sačinjavale 11.1% ukupne mokre mase sadržaja probavila. Sastav vrsta i njihova vertikalna raspodjela pokazali su da je kornjača bila u post-pelagičkoj razvojnoj fazi, hraneći se u plitkim obalnim vodama. Rezultati su raspravljeni u svjetlu novih nalaza juvenilnih primjeraka C. mydas u Albaniji i Grčkoj, što ukazuje na postojanje jonsko-jadranskog razvojnog puta zelenih želvi iz reproduktivnih staništa u istočnom Sredozemlju

Rare records of the false killer whales (Pseudorca crassidens) in the Adriatic Sea

In spring 2021, four unusual encounters with a group of false killer whales were recorded in Kvarner Bay, Northern Adriatic Sea. A minimum of five individuals, including a calf, were observed and two photos were taken corroborating species identification. These are the first reported sightings of the species in the Adriatic Sea since the mid-twentieth century. In addition, another encounter was revealed that occurred at the end of the 2000s in the same location and should be added to the list of historic observations. These reports were obtained by chance and show the importance of citizen science in obtaining data on rare marine species. The information gathered goes towards a better understanding of the distribution of the species in the Mediterranean Sea

Močvarni šišmiš Myotis dasycneme u Hrvatskoj

The pond bat Myotis dasycneme was recorded for the first time in Croatia. It was found wintering together with eight other bat species in Papuk Natural Park situated between the rivers Sava and Drava in the northeastern part of Croatia. Former mentions of the occurrence of M. dasycneme in Croatia were based on doubtful observations by Mojsisovics von Mojsvár in the 19th century.Krivo citirani podaci o nalazištima močvarnog šišmiša Myotis dasycneme iz starih radova austrijskog zoologa A. Mojsisovicsa von Mojsvára u XIX. stoljeću ispravljeni su prvim nalazom ove vrste u Hrvatskoj. Močvarni šišmiš je nađen na zimovalištu s još osam vrsta šišmiša u Parku prirode Papuk, između rijeka Drave i Save u sjeveroistočnoj Hrvatskoj

Dugoročno praćenje samotnog prugastog dupina (Stenella coeruleoalba) u priobalnom području Vinodolskog kanala, sjeverni Jadran

The striped dolphin (Stenella coeruleoalba) is not a common cetacean species in the northern Adriatic Sea. Its presence is generally related to deeper offshore areas beyond the continental shelf. Despite this fact, the analysis of data collected over the past 5 years indicates unusual site fidelity of a single individual in the relatively shallow Vinodol Channel of the northern Croatian Adriatic Sea. Summarizing the available data on its recent occurrence, this paper contributes to the current limited knowledge on striped dolphin presence and associations not only in this region.Prugasti dupin (Stenella coeruleoalba) ne predstavlja uobičajenu vrstu za hrvatski dio sjevernog Jadrana. Obično nastanjuje duboka i otvorena mora iza kontinentalnog šelfa. Unatoč tome, analiza podataka sakupljenih tijekom proteklih 5 godina ukazuje na neuobičajenu privrženost jedinke prugastog dupina relativno plitkom području Vinodolskog kanala u hrvatskom dijelu sjevernog Jadrana. Sveukupni podaci o njegovom pojavljivanju predstavljeni su u ovom radu, pridonoseći time dosadašnjim ograničenim saznanjima o prisutnosti prugastih dupina, i to ne samo na ovom području

Razine organoklorovih spojeva u tkivima kratkokljunog običnog dupina, Delphinus delphis, iz sjevernog Jadranskog mora

We analyzed 17 polychlorinated biphenyls (PCBs) and 7 organochlorine pesticides (OCPs) in blubber, liver, muscle, lung, heart and kidney of an adult male short-beaked common dolphin (Delphinus delphis) found dead stranded on the island of Cres (Croatia) in 2004. The PCB profile was dominated by hexachlorobiphenyls (39.4 – 63.2% of ΣPCB), with PCB-153 exhibiting the highest concentrations across all tissues. The pattern of PCB tissue distribution (ÓPCB) showed the highest burdens in blubber > liver > kidney > heart > muscle > lung, which were positively correlated with tissue lipid content (rs = 0.986, p blubber > liver > kidney > lung > heart, with no correlation to tissue lipid content (p > 0.05). Total DDTs were lower than total PCB levels for all tissues, with ΣPCB/ΣDDTs ratios ranging from 1.3 in blubber to 5.9 in muscles. Blubber OC burdens recorded in our specimen were among the highest found in a dolphin in the Mediterranean after the year 2000. This result and the presence of mono-ortho substituted PCBs with dioxin-like toxicity in all our samples may present an additional factor of concern for the conservation of regional dolphin populations.Analizirali smo 17 poliklorbifenila (PCB) i sedam organoklorovih pesticida (OCP) u potkožnom masnom tkivu, jetri, mišiću, plućima, srcu i bubregu odraslog mužjaka kratkokljunog običnog dupina (Delphinus delphis) koj je nađen nasukan na otoku Cresu (Hrvatska) 2004. godine. PCB profilom dominirali su heksaklorobifenili (39.4 – 63.2% ΣPCB), s PCB-153 utvrđenim s najvišim koncentracijama u svim tkivima. Raspodjela PCB-a u tkivima slijedi redoslijed: potkožno masno tkivo > jetra > bubreg > srce > mišić > pluća te pozitivno korelira sa sadržajem masti u pojedinom tkivu (rs = 0.986, p potkožno masno tkivo > jetra > bubreg > pluća > srce te ne pokazuje korelaciju sa sadržajem masti (p > 0.05). U svim su tkivima razine ukupnih DDT-a bile niže od razina ukupnih PCB-a, a omjeri ΣPCB/ΣDDTs u rasponu su od 1.3 u potkožnom masnom tkivu do 5.9 u mišiću. Razine organoklorovih spojeva u analiziranom uzorku potkožnog masnog tkiva među najvišim su nađenim razinama u dupinima u Sredozemnom moru nakon 2000. godine. Taj podatak te prisutnost mono-ortho supstituiranih PCB-a koji pokazuju toksičnost sličnu dioksinima u svim našim uzorcima mogu predstavljati dodatan razlog ugroženosti regionalne populacije dupina

Apparent increasing importance of Adriatic Sea as a developmental habitat for Mediterranean green sea turtles (Chelonia mydas)

In the Mediterranean, the green sea turtle (Chelonia mydas) has exhibited increase in the number of nests over the past two decades. While the Eastern Mediterranean is recognized as a high use area, scarce observations of green turtles in Adriatic Sea suggested only low-level utilization of this area. This study presents new findings of green sea turtles in the Adriatic Sea and analyses the importance of the region for the species. In combination with published records, we present 75 findings of the species in the Adriatic including eight new records. The number of records is generally low but shows an intriguing ten-fold increase since 2000. This may be a result of three confounding factors: (i) positive population trend at main nesting sites in Mediterranean; (ii) increased institutional capacity for sea turtle research and conservation in the past two decades, and (iii) raising sea temperatures. Documented increases in the sea surface temperatures may have established suitable and recurring thermal corridors along Ionian-Adriatic developmental pathway and provided environmental cues for immigration of juvenile green turtles into the Adriatic. As the abundance of the species will likely increase in the future, research and conservation efforts will be needed to avoid the Adriatic Sea becoming a sink habitat for the Mediterranean green turtle population