Repository of the Department of Marine Studies at the University of Split
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Croatian foreign trade of fisheries products in the period 2001-2020
No full textCilj rada je deskriptivno analizirati vanjskotrgovinsku razmjenu Republike Hrvatske
proizvodima ribarstva u razdoblju 2001.-2020. godine te utvrditi kretanje udjela proizvoda
ribarstva u ukupnoj vanjskotrgovinskoj razmjeni, strukturu i vrijednost izvoza i uvoza
proizvoda ribarstva, bilancu vanjskotrgovinske razmjene i pokrivenost uvoza izvozom
proizvoda ribarstva u analiziranom razdoblju. Tijekom analiziranog razdoblja u svim godinama,
izuzev 2005. godine, zabilježen je vanjskotrgovinski suficit za proizvode ribarstva, a najveći
suficit od 101 milijun USD bio je u 2020. godini. Pokrivenost uvoza proizvoda ribarstva
izvozom u razdoblju 2001.-2020. godine kretala se od 98,9% (2005.) do 162,5% (2020.). Na
pozitivnu vanjskotrgovinsku bilancu Republike Hrvatske za proizvode ribarstva u najvećoj
mjeri utječe izvoz atlantske plavoperajne tune. Tijekom cijelog analiziranog razdoblja veći je
udjel proizvoda ribarstva u ukupnom robnom izvozu nego u uvozu. Vrijednosno najvažnija
izvozna odredišta proizvoda ribarstva u 2020. godini su Italija, Japan, Španjolska i Slovenija,
dok u vrijednosnoj strukturi uvoza dominiraju Španjolska, Italija, Slovenija i Nizozemska.The goal of the work is to descriptively analyze the foreign trade exchange of fishery products
in the period 2001-2020 in the Republic of Croatia and to determine the movement of fishery
products shares in overall foreign trade exchange, its structure, and the import and export
fishery value, the balance of foreign trade exchange and the import and export coverage of the
fishery products in the analyzed period. During the included analysis of all recorded years,
except the year 2005, a foreign trade exchange surplus was spotted, and the biggest surplus of
101 million USD happened in the year 2020. The fishery products import and export coverage
of 2001-2020 was moved from 98.9% (2005) to 165.5% (2020). The positive foreign trade
balance of the Republic of Croatia for fishery products is largely influenced by the export of
Atlantic bluefin tuna. During the entire analyzed period, the share of fishery products in overall
exports is higher than in imports. The most significant import destinations in terms of the fishery
products value in the year 2020 are Italy, Japan, Spain, and Slovenia, while the countries that
dominate in the export value structure are Spain, Italy, Slovenia, and the Netherlands
Recent state of whale populations and their protection
No full textKitovi (Cetacea) dijele se na dva podreda: kitove zubane (Odontoceti) i kitove usane
(Mysticeti). Jedini su sisavci koji su se u potpunosti prilagodili na život u vodi. Ima oko 88
recentnih vrsta, a osim mora, neke vrste nastanjuju i rijeke. Nalaze se na samom vrhu morskog
hranidbenog lanca, a jedina vrsta koja ugrožava njihov opstanak je čovjek, direktnim ili
indirektnim načinom ugroza, dok ostalih prirodnih neprijatelja gotovo i nemaju. Kitovi spadaju
među najugroženije skupine sisavaca. Najveće prijetnje su im uništavanje staništa, onečišćenje,
globalne klimatske promjene, izlovljavanje, slučajni ulovi i buka u moru. Raznim
međunarodnim sporazumima i nacionalnim zakonima nastoje se očuvati i zaštiti recentne
populacije kitova, a znanost svojim kontinuiranim praćenjem stanja njihovih populacija,
adekvatnim metodama istraživanja i provođenjem studija o interakcijama kitova i čovjeka može
tome značajno pridonijeti. Posljedice njihova izumiranja ili značajnog smanjenja brojnosti
imaju izrazito negativan utjecaj na morske ekosustave, a u konačnici i na ljude, zbog svoje
uloge očuvanja oceana i održavanja klime.Whales (Cetacea) are divided into two suborders: toothed whales (Odontoceti) and baleen
whales (Mysticeti). They are the only mammals that have fully adapted to life in water. There
are about 88 recent species, and they inhabit not only the sea but also rivers. They are at the
very top of the marine food chain, and the only species that threatens their survival are humans,
directly or indirectly, while they have almost no other natural enemies. Whales are among the
most endangered groups of mammals. The biggest threats to them are habitat destruction,
pollution, global climate change, fishery, accidental catches and noise in the sea. Various
international agreements and national laws aim to preserve and protect populations of whales.
The science, with its continuous monitoring of whales, adequate research methods and
conducting studies on whale-human interactions can contribute to this goal significantly. The
consequences of their extinction or a significant decrease in numbers are extremely negative
impact on marine ecosystems, and ultimately on humans, due to its role in ocean conservation
and climate maintenance
Distribution of polychaete Hermodice carunculata in the Mediterranean sea
No full textVrsta Hermodice carunculata je morski termofilni mnogočetinaš iz porodice Amphinomidae. U ovom radu su navedena osnovna obilježja ovog mnogočetinaša te neka od dosadašnjih istraživanja vezana za njegovu ekologiju i rasprostranjenost, s posebnim naglaskom na Sredozemno more. Važno je naglasiti da se ova vrsta u prošlosti mogla pronaći na većim dubinama u nekim područjima Sredozemnog mora, dok je tijekom posljednjih godina zabilježeno širenje populacije prema sjevernijim područjima, odnosno plitkim područjima infralitoralne stepenice stjenovitog dna. Vrsta H. carunculata je grabežljivac koji se hrani sesilnim i sedentarnim vrstama bentoskih zajednica, zbog čega bi značajno povećanje gustoće i rasprostranjenosti ove vrste moglo utjecati na ravnotežu biocenoza u Sredozemnom moru.The species Hermodice carunculata is a marine thermophilic polychaete from the Amphinomidae family. In this paper, the basic characteristics of this polychaete are listed, together with some of the previous research related to its ecology and distribution, with a special emphasis on the Mediterranean Sea. It is important to underline that in the past this species could have been found in deeper areas of the Mediterranean Sea, while in recent years there has been an expansion of the population towards northern areas, i.e., shallow areas of the infralittoral rocky bottom. The species H. carunculata is a predator that feeds on sessile and sedentary species of benthic communities, which is why a significant increase in density and distribution of this species could affect the balance of biocenoses in the Mediterranean Sea
Utjecaj želatinoznog zooplanktona na cirkulaciju ugljika u ekosustavu zapadnog Baltičkog mora
No full textThere is a growing interest in better understanding of the trophic role played by jellyfish in marine ecosystems, especially due to their rapid growth rates and potential to profit from advantageous conditions created by climate change. When jellyfish are present in high abundance, their blooms may shunt substantial amounts of carbon from the classical grazing chain towards the microbial loop. Jellyfish act as competitors and predators of forage fish, thus representing a threat to the abundance of high commercial interest stocks. The goal of the study was to investigate the extent of jellyfish feeding over fish larvae and the intensity of their competition with forage fish in the Western Baltic Sea. To do so, an existing Ecopath with Ecosim (EwE) model was updated to consider explicitly changes in the biomass of jellyfish. Novel data on jellyfish abundance and biomass during the period 1994-2022 was gathered from various sources such as scientific literature and public data sets. These data served for calibrating the new EwE model. Predictions about future scenarios up to 2100 were obtained through simulations executed with the new EwE model to account for the potential increase in jellyfish biomass under the prospected scenarios of climate change. The work shows that the already depleted stock of herring in the Western Baltic Sea is susceptible to being replaced by a growing abundance of jellyfish, thus resulting in a regime shift.Sve je veći interes za bolje razumijevanje trofičke uloge koju želatinozni zooplankton ima u morskim ekosustavima, posebno zbog brze stope rasta ove skupine organizama i potencijala za razmnožavanje u uvjetima stvorenim zbog klimatskih promjena. Kada su meduze i rebraši (želatinozni zooplankton) prisutni u velikom broju, njihova najezda može preusmjeriti znatne količine ugljika iz klasičnog lanca prema mikrobnoj petlji. Meduze i rebraši su konkurenti i grabežljivci male pelagičke ribe, te kao takvi predstavljaju prijetnju za stokove visokog komercijalnog značaja. Cilj ovog diplomskog rada je istražiti opseg hranjenja želatinoznog zooplanktona ličinkama riba i intenzitet njihove kompeticije s malom plavom ribom u zapadnom Baltičkom moru. U tu svrhu ažuriran je postojeći model Ecopath s Ecosimom (EwE) kako bi se uvidjele promjene u biomasi meduza i rebraša. Novi podaci o brojnosti i biomasi ove skupine za razdoblje od 1994.-2022. prikupljeni su iz različitih izvora kao što su znanstvena literatura i javni skupovi podataka. Ovi su podaci poslužili za kalibraciju novog EwE modela. Predviđanja o budućim scenarijima do 2100. dobivena su simulacijama provedenima s novim EwE modelom kako bi se uzela u obzir potencijalno povećanje biomase prema očekivanim scenarijima klimatskih promjena. Rad pokazuje da su već iscrpljeni stokovi haringe u zapadnom Baltičkom moru podložni promjenama zbog rastućeg broja meduza i rebraša, što rezultira promjenama u strukturi i funkciji ekosustava
Technological procedure of mussel farming Mytilus galloprovincialis Lamarck, 1819
No full textU ovom završnom radu je predstavljen važni jadranski školjkaš, dagnja Mytilus
galloprovincialis, Lamarck, 1819. U uvodnom dijelu opisana je povijest uzgoja školjkaša,
posebno duga tradicija uzgoja dagnje. Španjolska i Grčka su jedne od najvećih proizvođača
dagnji u Europi. U Hrvatskoj uzgoj dagnji ima dugu povijest, a tehnologija uzgoja se temelji
na tradicionalnom načinu uzgoja. No, uzgajivači ističu potrebu za modernizacijom
proizvodnje s ciljem skraćivanja uzgojnog ciklusa i lakšeg manipulativnog rada. U radu se
obrađuju opće biološke karakteristike vrste, način rasta, reprodukcija i životni ciklus. Detaljno
se iznosi tijek uzgojnog ciklusa, prihvat ličinki na kolektore, razvoj mlađi i rast do tržišne
veličine dagnje. Također, opisana je moguća pojava različitih bioagresora koji predstavljaju
opasnost u uzgoju, te sindromi koji se mogu javiti kod ljudi uslijed konzumiranja
kontaminiranih jedinki.This thesis presents an important Adriatic species, mussel Mytilus galloprovincialis Lamarck,
1819. The introductory part describes a history of shellfish farming, especially the long
tradition of mussel farming. Spain and Greece are one of the largest producers of mussels in
Europe. Croatia has a long history of mussel farming, with the cultivation tehnology still
based on the tradicional way of farming. However, the farmers emphasize the need to
modernize production in order to shorten the farming cycle and easily manipulate the farming
process. This thesis deals with the general biological characteristic of the species, growth,
reproduction and life cycle. Furthermore, a special review in the paper refers to the course of
the mussel reproduction cycle, the reception of larvae on the collectors, the development of
young mussels and growth to marketable size. Moreover, the paper deals with issues related
to the appearance of various bioaggressors that can be danger in farming and also syndromes
that can occur in humans due to the consumption of contaminated shellfish
Endocrine responses to stress in fish
No full textIspitivanja na koštunjačama iz uzgoja uvelike su pridonijela razumijevanju endokrinih osnova stresa kod riba; nasuprot tome, informacija o reakcijama na stres kod divljih riba i hrskavičnjača je vrlo malo. Analiza vremenskog tijeka aktivacije hipotalamusno-hipofizno-nadbubrežne osovine otkriva jaku neovisnost o temperaturi, pri čemu većina koštunjača prilikom stresa pokazuje vidljivi porast kortizola u plazmi unutar 10 minuta. Osim stresa, brojne druge varijable mogu utjecati na razine kortikosteroida, kao što su spol i zrelost, režim hranjenja te godišnje doba. Studije o pticama, koje žive slobodno, pokazuju da je stres u okolišu uglavnom uzrokovan nepredvidljivim promjenama, a oskudni podaci o ribama podupiru ovu teoriju. Postoji mogućnost korištenja reakcija na stres kao markera kvalitete okoliša, ali je najprije potrebno razumjeti osnove istih.Studies of farmed teleost fish stocks have contributed much to understanding of the endocrine basis of stress in fish; in contrast, information on stress responses in wild fish and elasmobranchs is quite few. An analysis of the hypothalamic-pituitary-interrenal axis' time course of activation reveals a usually strong independence from temperature, with most teleosts exhibiting a detectable rise in plasma cortisol within 10 minutes of stress. In addition to stress, a number of other variables can affect corticosteroid levels, such as sex and maturity, feeding regime, and season. Studies on free-living birds indicate that environmental stress is mostly caused by unpredictable change, and the scant information on fish supports this theory. It is possible to use stress reactions as a marker of environmental quality, but only after thoroughly understanding the fundamentals of reactions to stress
The impact of microplastics on meiofauna
No full textMikroplastika je sveprisutna i gotovo nema mjesta na Zemlji gdje se ne može pronaći, a pokazala se kao vrlo štetno zagaĎivalo čiji su se negativni učinci, u sinergiji s drugim zagaĎivalima, tek počeli otkrivati. Uzimajući u obzir količine proizvedene plastike, predviĎa se da će se onečišćenje okoliša mikroplastikom u sljedećim desetljećima povećati, kao i negativni učinci na okoliš i zdravlje ljudi. Meiofauna je važna komponenta bentonskih hranidbenih mreža te je zbog toga važno shvatiti u kolikoj mjeri zagaĎenje mikroplastikom utječe na tu skupinu organizama. U ovom radu dajemo pregled utjecaja mikroplastike na meiofaunu i na koje načine dospije u okoliš, te kako organizmi reagiraju na navedeni polutant.Microplastic is ubiquitous and there is almost no place on earth where it cannot be found. Moreover, it is a very harmful pollutant whose negative effects, in synergy with other pollutants, have only just begun to be revealed. Considering the amount of plastic produced, it is predicted that the microplastics pollution will increase in the coming decades, as well as the negative effects on the environment and human health. Meiofauna is an important component of benthic food webs, and therefore it is important to understand to what extent microplastic pollution affects this group of organisms. In this paper we describe the impact of microplastics on meiofauna and the ways it gets in the environment, also how organisms react to pollutant
Oceanographic characteristics of the Adriatic documented by the results of operational numerical models (summer, 2017)
No full textU ovom radu opisane su oceanografske karakteristike Jadrana korištenjem rezultata operativnih numeričkih modela. Analizirani meteorološki i hidrografski podaci karakteriziraju ljeto 2017. godine kao ekstremno toplo, a u većem dijelu Jadrana i kao ekstremno sušno. Ovakve vremenske prilike rezultirale su visokim vrijednostima temperature mora i rekordno visokim vrijednostima površinskog saliniteta. Cilj rada je bio analizirati različite fizikalne i biogeokemijske parametre u srpnju, kolovozu i rujnu 2017. godine. Analizirane su horizontalne i vertikalne razdiobe odabranih parametara hidrodinamičkog i biogeokemijskog modela Copernicus programa. Horizontalna polja oceanografskih parametara su se analizirala na 1, 50 i 100 m u zadanom periodu, dok su vertikalne razdiobe prikazane u točkama sjevernog (13°E, 44,5°N), srednjeg (16°E, 42,5°N) i južnog (18°E, 41,5°N) Jadrana. Rezultati oba modela su u skladu sa dugogodišnjim mjerenjima većine analiziranih parametara. NEMO model je reproducirao izmjerene ekstremne vrijednosti površinskih temperatura i saliniteta, kao i inverzni profil saliniteta zabilježen mjerenjima. BMF model je reproducirao ispodpovršinske maksimume u poljima otopljenog kisika, primarne proizvodnje, koncentracije klorofila i biomase fitoplanktona, što je dobro poznata karakteristika nabrojenih parametara u Jadranu u ljetnoj sezoni.This thesis describes the oceanographic characteristics of the Adriatic Sea using the results of operational numerical models. The analyzed meteorological and hydrographic data characterize the summer of 2017 as extremely warm and in most parts of the Adriatic as extremely dry. These weather conditions resulted in high values of sea temperature and record high values of surface salinity. The aim of the study was to analyze various physical and biogeochemical parameters during July, August and September 2017.The horizontal and vertical distributions of selected parameters of the Copernicus hydrodynamic and biogeochemical model were analyzed. The horizontal fields of oceanographic parameters were analyzed at 1, 50 and 100 m for a given period, while the vertical distributions were shown at points in the northern (13°E, 44.5°N), middle (16°E, 42.5°N) and southern (18°E, 41.5°N) Adriatic Sea. The results of both models are consistent with the long-term measurements of the majority of analyzed parameters. The NEMO model reproduced the measured extreme values of surface temperatures and salinity, as well as the inverse salinity profile recorded by the measurements. The BMF model reproduces subsurface maxima in the fields of dissolved oxygen, primary production, chlorophyll concentration and phytoplankton biomass, which is a well-known feature of the listed parameters in the Adriatic during the summer season
Distribution and biometric characteristics of the species sepia officinalis Linnaeus, 1758, in the Adriatic sea
No full textU ovom radu predstavljena su morfometrijska obilježja i rasprostranjenost obične sipe, Sepia officinalis Linnaeus, 1758, u istočnom dijelu Jadrana. Uzorci za biometrijsku analizu prikupljeni su tijekom 2017. i 2018. godine, na području srednjeg Jadrana, a rasprostranjenost je opisana na osnovu podataka MEDITS ekspedicija u razdoblju od 1996. do 2020. godine. U analiziranom uzorku od 45 primjeraka korištenih za morfometrijska mjerenja, 24 (53%) jedinke su bile ženke, a 21 (47%) mužjak. Omjer spolova (ž/m) iznosio je 1,14. Raspon dužine plašta ukupnog uzorka iznosio je 83 do 283 mm, a ukupna masa uzorka je bila u rasponu od 86,6 do 1400 g. Obična sipa rasprostranjena je u plitkom sjevernom Jadranu te u kanalskim područjima srednjeg Jadrana, na dubinama od 10 do 200 m. Najveća gustoća populacije vrste zabilježena je u dubinskom pojasu od 10 do 50 m. Morfometrijskom analizom pojedinih dijelova tijela utvrđeno je da nema statistički značajnih razlika između mužjaka i ženki, a analiza kljunova ukazuje na to da se s porastom dužine plašta najviše povećava dužina krijeste i dužina kape, a najsporije raste rostrum. Morfometrijskom analizom sipovine utvrđene su statistički značajne razlike između mužjaka i ženki za odnos širine sipovine i dužine plašta, odnos širine unutarnjeg konusa i širine sipovine te odnos širine vanjskog konusa i širine sipovine.In this thesis, morphometric features and distribution of the common cuttlefish, Sepia officinalis Linnaeus, 1758, in the eastern part of the Adriatic Sea are presented. The samples for the biometric analysis were collected during 2017 and 2018, in the Central Adriatic Sea, and distribution was described based on the MEDITS expedition data 1996-2020. In the analysed sample of 45 specimens used for morphometric measures, 24 (53%) individuals were females and 21 (47%) were males. The sex ratio (f /m) was 1,14. Dorsal mantle length of all specimens ranged from 83 to 283 mm, and the total body weight ranged from 86.6 to 1400 g. The common cuttlefish is distributed in the shallow Northern Adriatic and in the channel areas of the Central Adriatic, at depths from 10 to 200 m. The highest abundances were recorded in the depth stratum from 10 to 50 m. Morphometric analysis showed no statistically significant differences between males and females, and beak analysis indicated that with increasing mantle length increases the length of the crest and hood length, and the rostrum growth is the slowest. Morphometric analysis of cuttlebone revealed statistically significant differences between males and female for the width and dorsal mantle length ratio, the inner cone width and cuttlebone width ratio, and the outer cone width and cuttlebone width ratio
Rearing technology of meagre Argyrosomus regius (Asso, 1801)
No full textHama je brzorastuća i migratorna bijela vrsta ribe čije je meso bogato nutritivnim svojstvima.
Nekoć je bila vrlo rijetka u ribolovnom ulovu i dugo se smatrala ugroženom vrstom. U
posljednje vrijeme hama postaje sve značajnija vrsta u mediteranskoj akvakulturi. U ovom
radu je predstavljeno trenutno stanje uzgoja hame (Argyrosomus regius) u Mediteranu i
Hrvatskoj. Međutim, kao i kod drugih vrsta, u uzgoju hame nailazi se na poteškoće tijekom
uzgojnog ciklusa. U uzgojnom ciklusu hame poteškoće se javljaju tijekom ranih razvojnih
stadija, naročito u periodu navikavanja na peletiranu hranu te uslijed učinka ove ishrane na
razvoj, probavu, rast, preživljavanje i deformacije. Određeni problemi su svojstveni vrsti,
posebno njezino kanibalističko ponašanje koje utječe na stopu preživljavanja.Meagre is a fast-growing and migratory white fish whose meat is rich in nutritional
properties. It was once very rare in the fishing catch and was long considered an endangered
species. Recently, meagre has become an increasingly important species in Mediterranean
aquaculture. This thesis presents the current state of meagre (Argyrosomus regius) cultivation
in the Mediterranean and Croatia. However, as with other species, difficulties are
encountered in the cultivation of meagre during the breeding cycle. In the breeding cycle of
meagre, difficulties occur during earlier developmental stages, especially during the period of
getting used to pelleted food and due to the effect of this nutrition on development, digestion,
growth, survival and deformations. Certain problems are inherent to the species, especially its
cannibalistic behavior that affects its survival rate