The ecology and reproductive biology of the hawksbill turtle, Eretmochelys imbricata were studied in Kish Island, Persian Gulf. The studied parameters include: environmental factors such as air temperature and humidity, soil types in different habitats during the breeding season; parameters related to the females' body and hatchlings biometrics i.e. weight, curved carapace length (CCL), straight carapace length (SCL), curved carapace width (CCW) and straight carapace width (SCW); and parameters related to reproductive biology, i.e. breeding time during diurnal, total eggs laid, the numbers of normal and abnormal eggs, weight and diameter of the eggs, incubation period and hatching success (HS). The temperature, humidity and soil size in different nest sites were 18.5–31°C, 70 to 88% and 0.063 to 4 mm, respectively. Means of weight, CCL, SCL, CCW and SCW of the females were 39.8 kg, 71.6, 65.1, 65.2 and 51.8 cm, respectively. The average of total egg numbers, normal and abnormal eggs by each individual female were 92.9, 75.2 and 17.7 respectively. Diameter and weight of every egg measured 38.4 mm and 33.6 g. Average of incubation period and HS were 60.9 days and 75.8%. According to the positive and significant correlation between CCL and CCW with weight took exponential regression models.

Background: Aquaculture wastewater contains high levels of phosphate and nitrate. The reuse of this water requires standards beyond the secondary standards to eliminate more organic pollutants from aquaculture effluents. In this research, the removal of these pollutants from wastewater using Chlorella vulgaris and Fe3 O4 nanoparticles in the reactor space was investigated. Methods: This study was conducted on fish farms effluent in the laboratory system. For this purpose, a 5-L semi-industrial reactor with a mixer blade, porous plate, and a compressor was designed. Chlorella vulgaris samples were collected from the natural environment and cultured in the laboratory environment. Also, Fe3 O4 nanoparticles were prepared from Iranian Nano Pishgaman Company to make the desired solution. During the experiment (3 weeks), samples were taken weekly (in one phase) from the effluent. Dissolved oxygen (DO), pH, nitrate (NO3 ), and phosphate (PO4 ) factors from the influent and effluent of the farms were measured. The statistical data were analyzed using SPSS version 21 and Excel 2013. Results: The amounts of nitrate and phosphate were decreased by about 80.76 and 80.55% in the biological reactor, whereas these amounts were 70.52 and 70.48% in the nanoparticle reactor, respectively. Also, there were significant differences in the amounts of NO3 and PO4 between the control treatment and weekly treatment (P<0.05). Conclusion: Based on the results, both reactors were able to reduce nitrate and phosphate from aquaculture wastewater, but the efficiency of the biological reactor was higher than that of the nanoparticle reactor.

In total, there are 11 confirmed records of the olive ridley turtle, Lepidochelys olivacea, from the Persian Gulf through June 2015, including 9 and 2 records from northern and southern coasts of the Gulf, respectively. Furthermore, on 16 May 2013, nesting was recorded from Nayband Marine-Coastal National Park, which is the first record of olive ridley nesting in the Gulf and is also the most northerly nesting account for the species in the Western Indian Ocean. Although few, these records suggest that the species lives and reproduces in the Persian Gulf.

Fish are observed in different aquatic environments, including freshwater, marine and also intertidal zones. It is suggested that the urohyal bone is involved in the feeding function of fish. Information about the urohyal bone in different fish groups, including gobiids is rare. In the present study, changes in the shape of the urohyal bone were studied in seven gobiid fish from the intertidal environments of the Persian Gulf and the Gulf of Oman by applying shape analysis and geometric morphometric analyses. The results revealed that the shape of the urohyal bone in each species was distinct, which is almost consistent with their phylogenetic relationships. Periophthalmus waltoni inhabits often terrestrial habitats and requires a system to obtain food. The specific shape of the urohyal bone in this species probably results from a functional adaptation to obtain food from the terrestrial environment. Moreover, our results indicated that the shape variation in the urohyal bone of the studied species is linked to their feeding because the calculation of E index categorized those species with similar feeding regimes into one group. In conclusion, we assumed that the urohyal shape variation in the studied gobiid species is the result of compatibility to the various feeding regimes, and it is likely controlled by genetic factors. Furthermore, the results support the usefulness of the urohyal bone morphology in differentiating the studied gobiid species and highlighting the taxonomic value of the urohyal bone.