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The bottlenose dolphin (Tursiops truncatus) is a cetacean distributed worldwide with an external morphology that varies between different populations. An endangered population of bottlenose dolphins inhabits the Adriatic Sea and is legally protected. The skulls of 95 adult bottlenose dolphins (47 females and 43 males, 5 of unknown sex) were morphometrically analyzed. They originated from bottlenose dolphins stranded dead from 1990 to 2011 in the Croatian part of the Adriatic Sea. For each animal a total of up to 53 skull measurements and meristic characters were taken using slide calipers to the nearest 0.01 cm. Sexual dimorphism within the Adriatic population was analyzed while the average morphometric values of Adriatic specimens were compared with published values for the genus Tursiops from different geographical areas. Male Adriatic bottlenose dolphins were signifi cantly larger in terms of 19 craniometric characteristics compared to females. The male skull is wider along the rostrum, at the level of the braincase and at the orbital region. Their braincase is higher and longer and their teeth are higher. Comparison of morphometrical values between Adriatic bottlenose dolphins and populations from other seas confi rms geographical polymorphism within the species T. truncatus. Our study showed that the skull size follows Bergmann’s rule, with larger skulls found in colder waters, while smaller skulls are found in populations from temperate and tropical seas. Our results represent referent craniometrical values for the Adriatic bottlenose dolphin and should be used when implementing morphometry in population conservation.

The structure of the pituitary gland was studied in 3 bottlenose dolphins (Tursiops truncatus) from the Adriatic Sea. This species is legally protected in Croatia. All examined animals died of natural causes and were found stranded along the eastern Adriatic coast. The pituitary gland is a rectangular body suspended at the base of the brain and situated in a depression of the sphenoid bone, clearly identififi ed as sella turcica. The gland was divided into the adenohypophysis and the eurohipophisis, interconnected by thick layer of connective tissue. Pars distalis and pars tuberalis were observed in the adenohypophysis while the pars intermedia was lacking. The pars distalis was built of three main cell types: acidophils, basophils and chromophobes. Most of the acidophils were situated in the centre of the gland while chromophobes occurred dorsal and basophils ventral. Pars tuberalis was composed of cords of polygonal and vacuolated cells, which were in close association with numerous blood vessels. Large numbers of colloid-containing follicles were observed throughout the pars tuberalis. The neurohypophysis of the bottlenose dolphin consisted of unmyelinated nerve fifi bres among which numerous pituicytes were scattered.

The measurement of bone mineral density (BMD) in dolphins was described in earlier investigations, but only by application of osteodensitometric methods used for man. The aim of this study was to test the possibilities of applying the method for small animals in the measurement of the bone mineral density in dolphins. The humeri of the right flfl ippers of 24 bottlenose dolphins (11 males and 13 females) were analyzed using the dual energy x-ray absorptiometry (DEXA) method for measurement and analysis of the bone mineral density in small animals. The tested method can be successfully applied for measuring bone mineral density in dolphins, but the range of measured values was lower than values that resulted from using the method for man. Statistical analysis indicated positive linear correlations between bone mineral density of dolphin humerus and the total body length and age of the dolphins.

Theaimofthisstudyistoexaminethedifferencesoftheflipperosteodensitometric characteristics in two dolphin sepcies which are morphologically very similar, but live in different environments. The pectoral flippers of 24 cetacean specimens representing two odontocete genera were obtained, 12 bottlenose dolphins (Tursiops truncatus) and 12 striped dolphins (Stenella coeruleoalba). External body measurements were taken and osteodensitometric properties (BMC, bone mineral content, and BMD, bone mineral density) were measured by DEXA method. Osteodensitometric parameters in the examined area were positively correlated to the flipper morphometric properties, especially to the cranial flipper length. Correlation of the greatest flipper width and osteodensitometric parameters is different in examined dolphin species. According to the bigger body size and stronger skeleton, bottlenose dolphin has higher osteodensitometric values than striped dolphin. Intensive body activity increase muscle mass and bone mineral density, and suggest higher forelimb muscle activity in bottlenose dolphin than in striped dolphin.

Dobri dupin (Tursiops truncatus Montagu, 1821) jedina je vrsta morskog sisavca koja u Jadranu obitava cijelu godinu. Populacija dupina, ne samo Jadrana već i globalno, sve je ugroženija djelovanjem klimatskih promjena, litoralizacije, izlovom ribe, sve intenzivnijim morskim prometom. Istraživanja dupina Sredozemnog mora malobrojna su, a čine osnovu za daljnje postupke u zaštiti i konzervaciji populacija. U ovom radu utvrđeni su i analizirani haplotipovi kontrolne regije mitohondrijske DNA populacije dobrih dupina Jadranskog mora te uspoređeni s ostalim objavljenim haplotipovima. Nakon izolacije DNA provela sam PCR reakciju, purifikaciju te sekvenciranje kontrolne regije, a zatim i računalne analize te izradila mreže. Istraživanje je pokazalo da populacija dobrih dupina Jadranskog mora ima 13 haplotipova kontrolne regije mtDNA od kojih su u ovom radu utvrđena dva nova (DD12 i DD13). Haplotipska raznolikost (Hd) iznosi 0,6831 a nukleotidna (π) 0,01085 što ukazuje na relativno visoku razinu genetičke raznolikosti. Mreža haplotipova dobivenih u ovom radu i onih preuzetih s GenBanka ne pokazuje jasnu filogeografsku strukturiranost populacija dobrih dupina Jadranskog, Sredozemnog, Crnog mora te sjeveroistočnog Atlantika. The bottlenose dolphin (Tursiops truncatus Montagu, 1821) is the only species of marine mammals that lives in the Adriatic Sea throughout the entire year. The population of dolphins, not only in the Adriatic but also globally, is increasingly threatened by climate change, littoralisation, fishing and growing marine traffic. Studies of the Mediterranean Sea dolphins are few, and form the basis for further action for the protection and conservation of their populations. In this graduation thesis, the mitochondrial DNA control region haplotypes of the bottlenose dolphin population in the Adriatic Sea have been identified and compared with other published haplotypes. After isolating the DNA, I performed the PCR reaction, purification and sequencing of the control region, followed by computer analysis, after which I constructed the haplotype networks. The study has shown that the common bottlenose dolphin population of the Adriatic Sea has 13 mtDNA control region haplotypes, of which two new haplotypes (DD12 and DD13) have been identified in this graduation thesis. The haplotype diversity (Hd) is 0,6831 and nucleotide diversity (π) is 0,01085, which points to a relatively high level of genetic diversity. The haplotype network showing a comparison of haplotypes determined in this graduation thesis and haplotypes downloaded from GenBank does not show a clear phylogeographic structure of populations of the Adriatic, the Mediterranean, the Black Sea and the northeast Atlantic.

Dobri dupin - Tursiops truncatus (Montagu, 1821) jedini je stalni morski sisavac Jadranskog mora te se pretpostavlja da u hrvatskom dijelu živi između 220 do 250 jedinki. Korišteni su uzorci dobrih dupina uginulih u hrvatskom dijelu Jadranskog mora i dva uzorka iz talijanskog dijela Jadrana. Cilj je utvrditi kraniometrijske značajke i raznolikost sljedova dijela kontrolne regije mtDNA dobrog dupina iz Jadranskog mora. Unutar 108 jedinki postoji 11 različitih haplotipova. Najučestaliji je haplotip DD01. Genska raznolikost iznosi 0,6108, a nukleotidna 0,010452. Haplotip DD07 je jedinstven. U 96 lubanja odraslih jedinki nađeno je da se mužjaci i ženke jadranske populacije razlikuju u 19 kraniometrijskih mjera, u mužjaka je lubanja robusnija. Lubanje dupina izraelskih, crnomorskih, kineskih te istočno floridskih populacija su kraće, a u populacija iz istočnog Atlantika, Sjevernog mora, mora oko Mauritanije, mora oko Južnoafričke Republike i iz mora oko Australije znatno su dulje su od lubanja jadranskih dobrih dupina. Bottlenose dolphin - Tursiops truncatus (Montagu, 1821) is the only resident marine mammal in the Adriatic Sea, and it is assumed that in the Croatian part live between 220-250 individuals. Carcasses of bottlenose dolphins from the Croatian part and two samples from the Italian part of the Adriatic were used. The goal is to determine craniometrical features and diversity of the mtDNA control region of bottlenose dolphins from the Adriatic Sea. Among 108 individuals, there are 11 different haplotypes. The most common haplotype is DD01. Genetic diversity was 0.6108, and nucleotide 0.010452. Haplotype DD07 is unique. Males and females of Adriatic population differ in 19 skull variables, in males the skull is more robust. Skulls of Israeli, Black Sea, Chinese and Eastern Florida populations are shorter, while skulls of populations from the Eastern Atlantic, North Sea, the seas around Mauritania, South Africa and Australia are considerably longer than the skulls of Adriatic bottlenose dolphins.