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The total length of 1065 individuals of Zosterisessor ophiocephalus ranged from 5.4 to 20.0 cm (mean 12.64 ± 2.51) and weight from 1.20 to 76.96 g (21.34 ± 12.70). The calculated length-weight equation for all individuals was TW (g) = 0.010TL2.90, R2 = 0.950 ; for females TW (g) = 0.012TL 2.890, R2 =0.951 and for males TW (g) = 0.012TL2.895, R2 = 0.950. There was no statistically significant difference of the length-weight regressions between sexes (ANOVA, p > 0.05). The ages ranged from 1 to 5 years. The values of the VBGE parameters pooled for both sexes are L∞ = 21.14 cm, K = 0.35 year-1, t0 = - 0.32 year-1. Total mortality, corresponding to descending limb of the length- converted catch curve, was Z = 0.442 per year for females and Z = 0.510 per year for males.

In this third Collective Article, with fisheries-related data from the Mediterranean Sea, we present the historical length distribution of Lophius budegassa in the catch of commercial trawlers in the Greek seas ; length-weight and length-length relationships of five flatfish species (Lepidorhombus boscii, L. whiffiagonis, Platichthys flesus, Pegusa lascaris and Solea solea) from different coastal areas of Turkey (Black Sea and Eastern Mediterranean Sea) ; growth of settled Polyprion americanus and length-weight relationships of this species and of Deltentosteus quadrimaculatus, Capros aper and three commercially important groupers in the Eastern Mediterranean Sea ; the age, growth and mortality of Zosterisessor ophiocephalus in the Eastern Adriatic Sea ; the length-weight relationship and condition factor of Atherina boyeri in a Central Mediterranean semi-isolated lagoon, and also the length-weight and length- length relationships of three Alburnus species from different inland waters in Turkey.

Age, growth, and mortality of the edible crab, Cancer pagurus, were determined for the native population in South Wales (UK). Sampling was carried out on a monthly basis between February 2001 and September 2002. Carapace width ranged between 10.4 and 163 mm. Based on the carapace width frequency distribution, the Swansea and Gower population was composed mainly of males belonging to the first and second age-class (1 and 2), and of females belonging to the third and fourth age-class (3 and 4). Sex ratio was 1.126 0.27 in favour of males. Carapace width frequency distributions and weight-at-age data were used to estimate the von Bertalanffy growth equation parameters. For the population as a whole, these were: L∞ = 199 mm, W∞ = 1179.56 g, K = 0.24 year 1, t0 = 0.1004 years. The overall carapace width–weight relationship was: W = 0.38 (CW2.69). Analysis of covariance indicated a significant difference in the carapace width–weight relationship between males and females in the study area. Total mortality Z and natural mortality M rates for combined sexes were 1.245 year 1 and 0.567 year 1, respectively. The exploitation ratio E was estimated to be 54.43%.

The age and growth of golden grey mullet, Liza aurata (Risso, 1810), were determined from specimens collected in the Mirna estuary (northern Adriatic Sea) during December of 2001, 2002 and 2003. The age composition was established using scale readings and Bhattacharya’s method. Nine age classes ranging from 3.2 to 13.2 years (except 10.2 and 11.2) were defined by scale readings but only seven (age 3.2: 23.29 cm, age 4.2: 26.75 cm, age 5.2: 29.05 cm, age 6.2: 31.18 cm, age 7.2: 32.71 cm, age 8.2: 34.42 cm and age 9.2: 35.50 cm) were obtained by Bhattacharya’s method. Total length ranged between 21.7 and 40.4 cm. Mean length and weight at age data, as derived using scale readings, were used to estimate the growth parameters of the von Bertalanffy equation: L∞=40.0, K=0.214, to=-1.150 ; W∞=606g, K=0.162 and to=-1.962. The length-weight relationship indicated positive allometric growth (b=3.069).

The age, growth and mortality parameters of Scorpaena scrofa from the eastern middle Adriatic Sea were studied. Total lengths (TL) of 350 specimens ranging from 13.5 to 58.2 cm were obtained by trammel net fishing (2000-2005). Total weight was ranging from 60.0 to 3650.0g. The mean lengths, as well as the age frequency distributions of males and females were not significantly different. Scales showed clearly the ring pattern. The opaque ring was deposited during the summer months. The length-weight relationship showed a positive allometric growth (b = 3.165 ; R2 = 0.989). The parameters of the von Bertalanffy growth equation were: L∞ = 68.20 cm ; K = 0.084 per year ; t0 = -1.378 year ; R2 = 0.981. This study revealed that S. scrofa is a relatively slow growing and long-lived species with a life span in excess of 25 years. The mortality parameters were: Z=0, 27, M=0, 22 and F=0, 05.

Aspects concerning age, growth, reproduction and recruitment were analysed in the thin-lipped mullet, Liza ramada collected in Neretva river delta estuary (East Adriatic, Croatian coastline). The study was based on the collection of a total of 362 individuals on a monthly basis. The Bertalanffy growth curve parameters were estimated: TL∞ =59.96 cm, K=0.269 year-1, to=-0.455. Natural mortality was estimated at 0.32 year-1. Total mortality (Z) was estimated at 0.70 year-1 (range 0.55-0.85 year-1). Fishing mortality was estimated at 0.38 year-1 and the exploitation ratio at E=0.54. The gonad-somatic index profile shows a single peak during the year in October. The sex ratio profile shows skewed sex ratios throughout the year except the period prior to reproduction peak.

This paper deals with some aspects of age and size distribution structure, growth, length-weigth relationship, sex ratio, maturity and food items of that species in the middle eastern Adriatic (Croatian waters).

The total length of 1872 individuals of Diplodus annularis ranged from 3.3. to 20.0 cm. Maximum age was 13 yr and 5-yr old individuals dominated the catches (24.75%). The parameters of the von Bertalanffy growth equation were: Linf=22.6 cm, K=0.173y-1, to=-1.460 yr. The overall male:female ratio was 1:1.12.

Life history of the salema Sarpa salpa in the eastern Adriatic was studied from samples collected betwen October 2000 and November 2001. age and growth of salema were studied by analysis of scales. The salema is long-lived species. Individuals of 1 to 14 years were found.

Wild gilthead sea bream fingerlings (4.3&plusmn ; 1.8 g) were reared to portion size (250 g) in an ambient seawater system with varying temperature (10.3-24.3&ordm ; C) for 15.0-16.6 months. They were fed commercial crumbels and pellets alone (F1), or mixed with 35% chicken eggs (F2), or mixed with 35% blue mussel flesh (F3). The daily feeding rate, daily protein feeding rate, daily growth rate, feed efficency (FE), protein efficency ratio (PER), protein productive value (PPV) and specific growth rate (SGR) were calculated monthly after weighing. Fish fed diet F3 grew to 250 g significantly (P

Wild gilthead sea bream fingerlings (4.3&plusmn ; 1.8 g) were reared to portion size (250 g) in an ambient seawater system with varying temperature (10.3-24.3°C) for 15.0-16.6 months. They were fed commercial crumbles and pellets alone (F1), or mixed with 35% chicken eggs (F2), or mixed with 35% blue mussel flesh (F3). The daily feeding rate, daily protein feeding rate, daily growth rate, feed efficiency (FE), protein efficiency ratio (PER), protein productive value (PPV) and specific growth rate (SGR) were calculated monthly after weighing. Fish fed diet F3 grew to 250 g significantly (P

Age, growth and mortality of picarel Spicara smaris L. collected in the eastern middle Adriatic during April and May in 1999 were studied. The total lengths of individuals ranged from 6.3 to 19.8 cm, and the weight from 2.2 to 78.3 g. The slopes (b values) of the total length-weight regressions indicated negative allometric growth for females (b = 2.8+/- 0.03) and isometric growth for males (b = 3.08+/-0.04). The oldest female and male were 4 and 6 years, respectively. The von Bertalanffy growth parameters for the sexes combined were (L-infinity = 22.76 cm, K = 0.277, t(0) = -0.793). The overall sex ratio was 1 : 4.1 in favour of females. Individuals larger than 17.9 cm were all males.

The age, growth and mortality of the Mediterranean amberjack Seriola dumerili (Risso, 1810) were determined in 298 specimens collected in the south-eastern Adriatic Sea (Donji Molunat Bay) from 17 May to 26 June 1997. The total length ranged from 32.0 to 160.0 cm and weight from 0.5 to 46.5 kg. Ten age classes, ranging from 1 to 10 years were defined by scale readings. Mean total length and weight-at-age data were used to estimate the growth pasrameters of the von Bertalanffy equation: L=174.6 cm, K=0.190, t=-0.314 ; W= 79.01 kg, K=0.139 and t=-0.746. The length-weight relationship was estimated at: W=0.000123xLn2.847. The overall sex ratio was 1:1.06 in favour of males. Total (Z) and natural (M) mortality were found to be 0.41years-1 and 0.30years-1, respectively. The exploitation ratio (E=0.27) indicates that the fishing pressure on the Mediterranean ambverjack was low in th einvestigated region.

Age, growth and mortality of the blotched piearel, Spicara maena (L., 1758), were determined from specimens (N=1130) collected on the eastern central coast of the Adriatic Sea from 16 September to 10 October 1996. Total length ranged from 7.8 to 27.5 cm, while weight varied between 5.3 and 398.0 g. The von Bertalanffy growth equation was fitted on the basis of mean length-at-age data resulting in parameter values of L-infinity=24.82 (S.E.=0.369), K=0.532 (S.E.=0.0302), and t(0)=-0.089 (S.E.=0.0321) (R=0.9985). Weight growth constants were: W-infinity=211.17 (S.E.=14.843), K=0.504 (S.E.=0.0324), and t(0)=0.099 (S.E.-0.0.076) (R=0.9627). Weight increased allometrically fur both sexes together with b=3.12 (S.E.=0.025). The blotched picarel is a relatively long-lived species. The oldest male and female were estimated to be 8 and 3 years old, respectively. Total (Z) and natural (hl) mortality were 1.18 and 0.98 per year, respectively. The exploitation ratio E=0.17 revealed an underfished stock. The sex ratio was skewed in favour of malts (1.41:1). Sex reversal was mainly observed between 17.5 and 18.0 cm. Females were observed up to a total length of 19.8 cm. (

Age and growth studies of fish species are one of the main analytical models to analyze the dynamics of exploited fish population. In this study the author reviews the published data on age and growth parameters of some fish species in the Eastern Adriatic. Scales and otholits were the main calcified tissues employedfor age determination, while fin rays were scarcely used. Age and growth were determined for 17 fish species, which makes 14% of 120 commercially interesting species. According to presented results we can coclude that there is still much to work to be done in age and growth determination of commercially interesting fish species.

Round sardinella larvae was sampled in the period from 14 to 20 August 1989 at the station Stončica in the eastern middle Adriatic. Specimens were aged by means of growth increments in th sagittal otoliths. the Gompertz and Laird-Gompertz growth equations, commonly used in larval analysis, described the larval rowth of this species in the length range sampled. The initial length of round sardinella larvae at time t=0 was L=4.661 mm. The obtained value of the predicted length at metamorphosis was a=24.45 mm. The average growth (0.72 mm d-1) was estimated by the slope of a line fitted by least squares regression analysis to the relation between standard length and number of increments.

The growth rate of the few months old Mediterranean amberjack was studied throughout a period of one year in the Bay of Mali Ston. Sixty-nine fish with an average weight of 183 (SD=57.5) g and total length of 25.2 (SD=2.8) cm were settled in rearing cages (5x5x5m) on September 27. 1995 for the purpose of studying growth in weight and length. The fish were usually fed frozen sardines once a day, every other day. The first month of rearing the fish showed considerable growth in weight 328 (SD=92.7) g and length 28 (SD=2.5 cm). At the end of the one-year period, the reared fish averaged 1239 g (SD=129, 8) in weight and 47.8 cm (SD=1.7) in length. The condition factor throughout the etire period of rearing was relatively homogenous, at 1.38 (SD=0.15). Significant gains in the weight and length of fish can be noticed during the warmer periods of the year, while less are for the colder months. The fish preferred frozen sardines. During this experiment, we noted the mortality of 7 fish (10, 1%). Moreover, the sudden oscillations in the basic hydrographic parameters for this relatively enclosed bay can be attributed to the influence of th river Neretva.

In spite of the fact that gilt-head sea bream was the subject of intensive investigations in aquaculture, published reports on its biology and ecology and its natural environment were more frequent for the western that the eastern Mediterranean Sea. There is no data for the Adriatic Sea so the purpose of this paper is to present some new data on age and growth parameters of the gilt-head sea bream. The total length ranged from 15.0 to 70.0 cm and weight from 40 to 5900 g. Sixteen age classes, ranging from 1 to 22 years were defined by scale readings. Modal age was 1 year. Weight grew positively allometric with size (b=3.087). The mean condition factor was estimated as 1.36. Von Bertalanfy growth parameters are Linfinity=84.98 cm, K = 0.073, to=2.823, Winfinity = 12879.4g ; K=0.062 and t0=-2.728. The gilt-head sea bream is a long lived species and its growth is very slow in the eastern Adriatic. Its weight grew positively allometric sonce individuals were caught during spawning season (September-December).

The purpose of this work was to analyse and estimate the growth characteristics of sprat larvae from the North Adriatic for the first time as inferred from otolith daily growth increments. Sprat larvae were collected from th eNorth Adriatic inJAnuary 1996. They were aged using daily growth incremets in sagittal otoliths. Age at length of larvae was estimated by common non-linear growth equations. The data presented are consistent with the deposition of one complete increment per 24 h period. There was some evidence that daily growth increments are deposited on the otoliths of sprat larvae only after the onset of exogenous feeding. Integrated somatic growth was 0.398 mm d-1. This value is comparable to others obtained for similar pelagic clupeoid species. Sprat growth and development rates could be determined by analysis of otolith increments and growth parameters should be estimated for every particular survey when the data on age of larvae are needed.

The gilt-head sea bream is a long lived species and its growth is very slow in the eastern Adriatic. Its weight grew positively allometric since individuals were caught during spawning season ( September-December). Such investigations are necessary to be continued in order to establish some new biological and ecological parameters such as mortality rates.

Engraulis encrasicolus (L) was sampled between July and August 1991 in the North Adriatic Sea. Specimens were aged by means of growth increments in the sagittal otoliths. The Gompertz and Larid-Gompertz growth equations, commonly used in larval growth analysis, described the larval growth of this species in the length range sampled. The initial length of anchovy larvae at time t=0 was lo=2.71 mm. The obtained value of the predicted length at metamorphosis was a=36.87 mm. A growth rate of 0.94 mm d^-1 was calculated for 8 mm larvae at a mean temperature of 23.0^oC, whilst the greatest rate was 1.06 mm d^-1 for 14.3 mm larvae (14-day-old). Anchovy larvae in the North Adriatic sea grew at approximately the same rate as those in the Western Mediterranean Sea.

Sardina pilchardus and Engraulis encrasicolus larvae were aged by means of growth rings in the saggital otoliths. The Gompertz and Laird-Gompertz growth equations described the growth of these species in the length range sampled.

Engraulis encrasicolus were sampled in July/August 1990 in the Eastern Adriatic Sea, they were aged by means of growth rings in the sagittae. Length-age relationship was approximated by Gompertz and Laird-Gompertz functions with the high and statistically significant (P

Growth parameters of the fon Bertalanffy equation are: males - L = 32.82 cm, K = 0.40, Z/K = 1.965; females - L = 32.02 cm, K = 0.33, Z/K = 1.819; and whole material - L = 32.82 cm, K = 0.30, Z/K = 2.156. Length-weight relationship of male were W = 0.000011x Lt 3.068, SE(b) = 0.107, r2 = 0.978 and of female W = 0.000018x Lt3.047, SE(b) = 0.090, r2 = 0.985. Total mortality of whole peacock wrasse population was estimated as Z = 0.71, or Z = 0.82 for males and Z = 0.71 for females. Fishing mortality of whole population was estimated as F = 0.13. Natural mortaluity was estimated as M = 0.58 for whole population.

Aspects concerning age, growth, length-weight relationships and mortality were analysed in the golden grey mullet collected in Mirna Bay (eastern Adriatic). Mean length and age data, derived using scale readings were used to estimate the growth parameters of the von Bertalanffy equation. The theoretical maximum length was estimated to be L infinity=398 mm. The growth coefficient was K=0.21. Length-weight relationship indicated positive allometric growth in winter with a b-value of 3.16. Total (Z) and natural (M) mortalty were found to be 1.12 years^-1 and 0.44 years^-1 respectively. The exploitation ratio (E=0.61) indicates that the fishing pressure on the golden grey mullet was high in the region investigated.

Growth of black sea bream Spondyliosoma cantharus (L.) from the eastern middle Adriatic was studied using data on the scales, length and weight from 745 fish. Total length ranged between 6.2 and 46.5 cm, while weight varied between 3 and 2165 g. The von Bertalanffy growth equation was fitted on the basis of mean length-at-age data resulting in parameter values of L(infinity) = 47.7 cm, K = 0.178 and t(0) = -0.27. Weight growth constants are: W-infinity = 2269.2 g, K = 0.149 and t(0) = -0.74. Weight increased allometrically for both sexes together with b = 3.12 and in females alone with b = 3.14, while it increased isometrically in males with b = 2.99. The black sea bream is a long-lived species. The oldest male was estimated to be 14 and female 9 years old. The sex ratio rapidly became skewed in favour of females (3.12:1). Sex reversal was mainly observed in age classes 7 and 8. Females were found only up to a total length of 37.7 cm.

Sardina pilchardus were sampled during the period February-May 1991 and in April 1991 in the eastern part of the Adriatic and in the Bay of Biscay, respectively. Specimens were aged by means of growth in saggittal otoliths. the Gompertz and Laird Gompertz growz+th equations, commonly used in larval growth analysis, described the growth of this species in the length range sampled. The initial length of sardone larvae at time t=0 for the Adriatic Sea was 4.138 mm at a mean temperature of T=13.10oC. The daily growth rate was found to be slightly higher in sardine larvae from the Bay of Biscay than in those from the Adriatic, but the difference was not statistically significant.

Provedeno je prvo istraživanje bioloških i ekoloških osobitosti glavoča travaša, Zosterisessor ophiocephalus (Palllas, 1814) na području Novigradskog mora (Jadransko more). Tijekom istraživanja ulovljeno je 1229 jedinki, raspona ukupnih dužina tijela od 4,3 cm do 20 cm (12,30 ± 2,70 cm) i mase od 0,80 g do 76,96 g (20,11 ± 12,79 g). Omjer mužjaka i ženki iznosio je 1,13 : 1, što se statistički značajno ne razlikuje od očekivanog omjera (1:1). Srednja vrijednost ukupne dužine tijela mužjaka (13,11 cm) bila je statistički značajno veća od srednje vrijednosti ukupne dužine kod ženki (12,11 cm). Dužinsko maseni rast glavoča travaša bio je negativno alometrijski (b=2,920), a vrijednost indeksa kondicije iznosila je 0,953. Zabilježene su statistički značajne razlike u srednjim vrijednostima morfometrijskih odnosa mužjaka i ženki. Kod ženki i mužjaka uočen je spolni dimorfizam, zasnovan na obliku urogenitalne papile. Intenzitet hranjenja glavoča travaša bio je najveći u proljeće, a najmanji u zimskom razdoblju. Najvažniji plijen bili su rakovi i ribe. Starost glavoča travaša određena je očitavanjem otolita, najstarija ženka i mužjak imali su 5 godina. Rast glavoča travaša opisan je von Bertalanffyevim modelom (L∞=21,14 cm; K=0,351; t0= -1,321; R2=0,890). Razdoblje mrijesta je od veljače do svibnja, a najveće vrijednosti gonadosomatskog indeksa (GSI) zabilježene su u travnju. Relativni fekunditet ženki kreće se od 68,33 do 127,52. Niske vrijednost koeficijenta ukupne smrtnosti (Z=0,432) posljedica su relativno niske stope prirodne smrtnosti (M=0,344), dok je ribolovna smrtnost zanemariva jer glavoč travaš nije ciljana ribarstvena vrsta. Razina iskorištavanja glavoča travaša još nije upozoravajuća (E=0,203) za područje Novigradskog mora. The first study of biological and ecological characteristics of grass goby, Zosterisessor ophiocephalus (Palllas, 1814) was conducted in the area of Novigrad sea (Adriatic sea). During the research 1229 grass gobies was caught. The total body length was from 4,3 cm to 20 cm (12,30 ± 2,70 cm), and weighted from 0,80 g to 76,96 g (20,11 ± 12,79 g). Male to female ratio was 1,13:1, and it was not significantly differentiated from expected ratio (1:1). The medium value of the total body length of males (13,11 cm) was statistically significantly greater than the medium value of the total body length of females (12,11 cm). Length-weigh growth of grass goby was negative allometric (b=2,920), and the value of estimated condition index was 0,953. Statistically significant differences in the medium valued of morphometric relation of males and females are noted. Based on the shape of urogenital papillae sex dimorphism was noted it both male and female grass gobies. Feeding activity of grass gobies was the highest in spring, and the lowest in winter period. Essential prey was crustaceans and fish. Age was determined by specific reading of otoliths, and the oldest female and male were 5 years old. The growth of the grass goby was described by von Bertalanffy model (L∞=21,14 cm; K=0,351; t0=-1,321; R2=0,890). The spawning period was from February to May, and the largest value of gonadosomatic indeks (GSI) was noted in April. Relative female’s fecundity ranges from 68,33 to 127,52. Low values of total mortality coefficient (Z=0,432), is a consequence of relatively low natural mortality rate (M=0,344), while fishing mortality is insignificant due to the fact that grass goby is not a fishery species. Exploitation rate of the grass goby is still not alarming (E=0,203) for Novigrad sea.