SHELLFISH OF THE RIVER KRKA MOUTH - FISHING AND FARMING

U radu je iznesen kratki prikaz zemljopisnog položaja rijeke Krke, osobitosti njezina ušća, to izlova i istraživanja prirodnih populacija školjkaša. Poseban je naglasak stavljen na prikaz mogućnosti kontroliranog uzgoja školjkaša u bočatim vodama ušća. U ušću rijeke Krke utvrđeno je 56 svojti iz 27 porodica. Najrasprostranjenije su ove svojte: dagnja (Mytilus galloprovincialis), kamenica (Ostrea edulis), a česte su: jestiva srčanka (Cerastoderma glaucum), prnjavica (Venus verrucosa), kućica (Tapes decussatus), kunjka (Arca noae), mala kapica (Chlamys varia) i jakovska kapica (Pecten jacobaeus). Izlov prirodnih populacija školjkaša za prehranu tradicionalna je djelatnost i procjenjuje se na 100 tona u godini. Istraživanja mogućnosti kontroliranog uzgoja dagnje, kamenice, male kapice i jakovske kapice rezultirala su razvojem tehnologija konroliranog uzgoja dagnje i kamenice 1983., a jakovske kapice i male kapice godine 1989. Danas je proizvodnja organizirana na 25 lokaliteta, ukupne površine 87.142 m2, s mogućnošću proizvodnje oko 1.500 tona dagnji i deset tisuća kamenica, a mogla bi se povećati iznad 10.000 tona.Krka River spring is at the foot of Dinara mountain, starting from a 22 m high Topoljski waterfall. Its length is 72.5 km, and total slope 242 m. The length of freshwater waterway is 49 km and brackish waterway, i. e. flooded river mouth, 23.5 km long. Impact of seawater and depth of surface fresh water greatly vary depending on the river waterlevel, local precipitation, tides and wind directions. Owing to the extensive primary production in the river mouth shellfish are abundantly present with 56 species. The most abundant are Mediterranean mussel (Mytilus galloprouincialis) and flat oyster (Ostrea edulis), and partly common cockle (Cerastoderma glaucum), Venus shell (Venus verucosa), calico clam (Tapes decussates), Noah\u27s arc (Arca noae), variegated scallop (Chlamis uaria) and Pilgrim\u27s scallop (Pecten jacobaeus). Owing to very productive processes in the ecosystem of river mouth, fishing in the area is traditionally practice. The knowledge about natural populations of Mediterranean mussel fished out in quantities larger than 100 t/y have initiated the research on since 1979 shellfish in this area. Investigations on possibilities of commercial farming of Mediterranean mussel, flat oyster, variegated scallop and Pilgrim\u27s scallop (Pecten jacobaeus) resulted in defining the technological procedure for commercial farming of Mediterranean mussel and flat oyster (1983), and variegated scallop and Pilgrim\u27s scallop (1989). Nowadays at 25 localities of 87.000 m2 area and with 19 concessions a total production around 1500 t/y of Mediterranean mussel and about 10.000 pieces of flat oyster is provided, and there is also significant possibility to increase production up to 10.000 tons

ATTACHMENT OF LARVA, SURVIVAL AND GROWTH OF JUVENILE SCALLOPS (Pecten jacobaeus Linnaeus, 1758) IN CONTROLLED BREEDING IN ŠARINA DRAGA BAY —MOUTH OF THE KRKA RIVER

Izlovljavanje jakovske kapice (Pecten jacobaeus Linnaeus, 1758.) iz prirodnih populacija u Hrvatskoj obavlja se sporadično i neorganizirano, uglavnom kao sekundarna djelatnost pri ulovu ribe, a kontrolirani uzgoj ne postoji. Istraživanja gonadnog indeksa odraslih jakovskih kapica, prihvata ličinki, stupnja preživljenja i rasta juvenilnih stadija provedena su radi utvrđivanja mogućnosti kontroliranog uzgoja i uvođenja nove vrste u akvakulturnu proizvodnju u Hrvatskoj. Sposobnost obnavljanja populacije varira u vremenu i prostoru, ovisno o hidrografskim značajkama ušća rijeke Krke. Najpovoljnije razdoblje za kolektiranje mlađi jest ožujak/lipanj, a najpovoljnija dubina 6–8 m iznad morskoga dna. Vertikalni prihvat mlađi obrnuto je proporcionalan salinitetu. Najniži salinitet na kojem su utvrđeni prihvat i preživljenje ličinki iznosi oko 20 x 10–3, a uspješno kolektiranje moguće je uglavnom pri salinitetima višima od 30 x10–3. U pokusnom uzgoju jakovske kapice starosti 6 mjeseci, srednje veličine 33,1±5,5 mm i srednje mase 8,8 g, nakon godinu dana, postigle su srednju veličinu 83,8±9,5 mm i srednju masu 80,6 g. Ukupni mortalitet za vrijeme istraživanja iznosio je 33%.The capture of scallops (Pecten jacobaeus Linnaeus, 1758) from natural populations in Croatia is sporadic and unorganizaed, as a secondary activity in fishing, while no controlled cultivation of this species exists. Research of the gonad index of adults, larvae attachment, survival and growth of juvenile scallops was conducted with the aim of determining the possibility of the establishment controlled cultivation and in this way the introductes new species in Croatia’s aquaculture production. The capability to replace the population varies in time and space, and is dependent upon the hydrographical characteristics of the river mouth. The most favourable period for collecting juveniles is March–June between 6 to 8 meters depth above the sea bottom. The vertical attachment of juveniles is inversely related to salinity. The lowest salinity for attachment and juveniles survived was about 20 x 10–3, while successful collection is possible at salinities above 30 x 10–3. Shellfish aged 6 months, mean size of 33.1±5.5 mm and with a mean mass of 8.8 g reached mean sizes of 83.8±9.5 mm and mean mass of 80.6 g at one year. Total mortality during this study was 33%

TWENTY YEARS OF RESEARCH AND SHELLFISH FARMING IN THE MOUTH OF THE KRKA RIVER

U radu je dan kratak prikaz aktivnosti tijekom dvadeset godina istraživanja i kontroliranog uzgoja školjkaša u bočatim vodama ušća rijeke Krke. Poseban je naglasak stavljen na zakonsku podlogu za dodjelu koncesija i istaknuti su problemi koji sputavaju razvoj akvakulture u ovom izuzetno produktivnom području u kojem bi se, prema dosadašnjim spoznajama proizvodnja morskih organizama mogla višestruko povećati bez znatnijeg narušavanja ekološke stabilnosti akvatorija. U analizi mogućnosti daljnjeg povećanja uzgoja predlaže se kontrolni uzgoj dagnji i kamenica u polikulturi s ribama, a tako|er sekundarni uzgoj jakovske i male kapice u polikulturi s dagnjama i/ili kamenicama u dubljim dosad neiskorištenim vodenim slojevima.This work shows a short review of activities in the twenty years of research and controlled shellfish farming in the brackish waters of the mouth of the Krka River. Legislative background for granting concessions was especially emphasized as well as problems limiting aquaculture development in this extremely productive area where, according to the latest facts, the production of sea organisms could witness a manifold increase without any substantial disturbance of the ecologic stability of the aquatorium. The analysis of the further farming increase suggests controlled mussel and oyster culturing thus making a polyculture with fish; as well as a secondary culturing of scallops and cockles within the mussel and/or oyster polyculture process in deeper water layers which have not been exploited up to now

ATTACHMENT OF LARVA, SURVIVAL AND GROWTH OF JUVENILE VARIANT SCALLOPS (Chlamys varia Linnaeus, 1758) IN CONTROLLED BREEDING IN ŠARINA DRAGA BAY — MOUTH OF THE KRKA RIVER

Kontrolirani uzgoj male kapice (Chlamys varia Linnaeus, 1758) u Hrvatskoj ne postoji, a iz prirodnih se populacija izlovljava sezonski, sporadično i neorganizirano. Istraživanja indeksa kondicije adultnih malih kapica, prihvata ličinki, stupnja preživljenja i rasta juvenilnih školjkaša provedena su radi utvrđivanja mogućnosti njezina kontrolirana uzgoja. Rezultatima istraživanja utvrđeno je da mala kapica ima dualni tip mriješćenja, s primarnim maksimumom u proljeće (ožujak/svibanj) i sekundarnim u jesen (listopad). Najpovoljnije razdoblje za kolektiranje mlađi jest srpanj/rujan, a najpovoljnija dubina 2–10 m iznad morskoga dna. Najniži salinitet na kojem su utvrđeni prihvat i preživljenje ličinki jest oko 20 x 10–3, a uspješno kolektiranje moguće je uglavnom pri salinitetima višima od 30 x 10–3. U pokusnom su uzgoju male kapice, srednje veličine od 16,4±2,1 do 17,6±2,2 mm i srednje mase 0,95 do 1,35 g, nakon godinu dana postigle srednju veličinu od 42,7±3,2 do 47,5±3,0 mm i srednju masu od 12,1 do 17,5 g. Ukupna smrtnost za vrijeme istraživanja iznosila je od 25 do 57%.In Croatia, the capture of scallop (Chlamys varia Linnaeus, 17583) from natural populations are sporadic and unorganized, while there is no controlled cultivation of this species. To determine the possibility of the establishment of their commercial cultivation, the research comprehended the condition index of adults, larval attachment, juvenile survival and growth in Šarina draga Bay, in a locality with dense scallop populations. The changes of condition index shoved on main spawning season in spring (March–May) and second one, but less intensive, in autumn (October). According to results, the best season for juvenile collection is recommended the period from July to September at depths between 2 to 10 m, and salinities above 30 x 10–3. Low larval settlement at 2.5 m depth is surely result of salinity decrease by Krka river intensive fresh water inflow. Shellfish mean size from 16.4±2.1 to 17.6±2.2 mm and with a mean mass from 0.95 to 1.35 g reached mean size from 42.7±3.2 to 47.5±3.0 mm and mean mass from 12.1 to 17.5 g in one year. Total mortality during this study was ranged from 25 to 57%

DALMATIAN TURKEY – AN ARCHAIC FORM OF POULTRY

Potpisom Konvencije o biološkoj raznolikosti Republika Hrvatska aktivno se uključila u očuvanje ukupnog biodiverziteta. Od autohtonih pasmina peradi za sada su u Popis izvornih i zaštićenih pasmina i sojeva domaćih životinja nastalih na teritoriju Republike Hrvatske upisani zagorski puran i kokoš hrvatica. No, proces identifikacije te karakterizacije pojedinih tradicionalnih formi životinja koje se uzgajaju na nekom području još traje. Među takve tradicionalne oblike spada i dalmatinska tuka, koja se na području dalmatinskog zaleđa uzgaja generacijama. Navedena forma pura, povijesno uključena u tradiciju kraja, uspjela se održati zbog izričite sklonosti žitelja tog područja tradicionalnom te zbog njihove visoke primjerenosti ruralnom uzgoju, kao i lokalnim društvenim i gospodarskim prilikama. Svjesni činjenice da se u arealu dalmatinskih tuka sve češće ekstenzivno uzgajaju različiti hibridi pura, nalazimo nužnim što prije utvrditi njihove prosječne morfološke i fiziološke odlike da bismo mogli dati osnovne smjernice za karakterizaciju pasmine, procijeniti veličinu populacije čistih jata, ustanoviti jata sa primjesama krvi hibrida te usmjeriti uzgoj roditeljskih parova u čistoj krvi. Uz znanstvenu, stručnu te komercijalnu podršku od dalmatinskih bi se tuka mogao razviti još jedan snažan gastronomski simbol Dalmatinske zagore. Na taj bi način njihov tradicionalni, a pritom komercijalni uzgoj na obiteljskim poljoprivrednim gospodarstvima mogao imati primjetne promidžbene učinke i donositi znatne prihode.After signing the Convention of Biological Diversity, the Republic of Croatia has been actively included into preservation of biological and landscape diversity. Today, Hrvatica Hen and Zagorje Turkey are the only two autochthonous breeds of poultry that are included into the National Register of Autochthonous Breeds. However, processes of identification and characterization of autochthonous breeds are still continuing. Dalmatian Turkey can also be included in those traditional forms. As an archaic form of turkey it has been traditionally reared in the area of the Dalmatian hinterland. It is historically involved in the tradition of this region and maintained due to local inhabitants and their tendency towards traditional forms. Furthermore, those turkeys are suitable for extensive breeding, as well as for the local social and agricultural conditions. The daily increasing number of hybrids causes decrease of the amount of Dalmatian Turkey in this area. For that reason we find it necessary to determine their average morphological and physiological characteristics as soon as possible. In this way it will be possible to determine the main trends for breed characterization, to find flocks without influence of other breeds or hybrids, to determine the average population size, as well as to find parental flocks for further breeding and selection. With the scientific, professional and commercial support, Dalmatian Turkey may also present a culinary speciality from the Dalmatian hinterland. In this way, traditional, but commercial breeding on family farms could increase the budget and the standard of this region

DALMATIAN TURKEY – AN ARCHAIC FORM OF POULTRY

Potpisom Konvencije o biološkoj raznolikosti Republika Hrvatska aktivno se uključila u očuvanje ukupnog biodiverziteta. Od autohtonih pasmina peradi za sada su u Popis izvornih i zaštićenih pasmina i sojeva domaćih životinja nastalih na teritoriju Republike Hrvatske upisani zagorski puran i kokoš hrvatica. No, proces identifikacije te karakterizacije pojedinih tradicionalnih formi životinja koje se uzgajaju na nekom području još traje. Među takve tradicionalne oblike spada i dalmatinska tuka, koja se na području dalmatinskog zaleđa uzgaja generacijama. Navedena forma pura, povijesno uključena u tradiciju kraja, uspjela se održati zbog izričite sklonosti žitelja tog područja tradicionalnom te zbog njihove visoke primjerenosti ruralnom uzgoju, kao i lokalnim društvenim i gospodarskim prilikama. Svjesni činjenice da se u arealu dalmatinskih tuka sve češće ekstenzivno uzgajaju različiti hibridi pura, nalazimo nužnim što prije utvrditi njihove prosječne morfološke i fiziološke odlike da bismo mogli dati osnovne smjernice za karakterizaciju pasmine, procijeniti veličinu populacije čistih jata, ustanoviti jata sa primjesama krvi hibrida te usmjeriti uzgoj roditeljskih parova u čistoj krvi. Uz znanstvenu, stručnu te komercijalnu podršku od dalmatinskih bi se tuka mogao razviti još jedan snažan gastronomski simbol Dalmatinske zagore. Na taj bi način njihov tradicionalni, a pritom komercijalni uzgoj na obiteljskim poljoprivrednim gospodarstvima mogao imati primjetne promidžbene učinke i donositi znatne prihode.After signing the Convention of Biological Diversity, the Republic of Croatia has been actively included into preservation of biological and landscape diversity. Today, Hrvatica Hen and Zagorje Turkey are the only two autochthonous breeds of poultry that are included into the National Register of Autochthonous Breeds. However, processes of identification and characterization of autochthonous breeds are still continuing. Dalmatian Turkey can also be included in those traditional forms. As an archaic form of turkey it has been traditionally reared in the area of the Dalmatian hinterland. It is historically involved in the tradition of this region and maintained due to local inhabitants and their tendency towards traditional forms. Furthermore, those turkeys are suitable for extensive breeding, as well as for the local social and agricultural conditions. The daily increasing number of hybrids causes decrease of the amount of Dalmatian Turkey in this area. For that reason we find it necessary to determine their average morphological and physiological characteristics as soon as possible. In this way it will be possible to determine the main trends for breed characterization, to find flocks without influence of other breeds or hybrids, to determine the average population size, as well as to find parental flocks for further breeding and selection. With the scientific, professional and commercial support, Dalmatian Turkey may also present a culinary speciality from the Dalmatian hinterland. In this way, traditional, but commercial breeding on family farms could increase the budget and the standard of this region