Juniper Publishers-Oceanography Open Access Journal

  Juniper Publishers -  Journal of Oceanography Abstract Coastal urbanization is often accompanied by the replacement of natural substrata by artificial structures, which causes coastal habitat modifications, losses of species richness, diversity and microhabitats diversity and favours the settlement of non-native species. The impact that coastal defence structures cause in the intertidal community is further favoured by the anthropic pressures produced in heavily populated areas (such as pollution or the collection of intertidal organisms). Among these, the effect of artificial lights on intertidal communities is practically unknown, even though that the behaviour of many intertidal vagile organisms is synchronized with circatidal and circadian rhythms. Considering that large areas of natural and artificial habitats are exposed to artificial illumination, this review exposes the current knowledge in this matter in order to evaluate the importance of this disregarded impact. N...

  Juniper Publishers -  Journal of Oceanography Abstract This mini review describes the development of an acoustic tag for long-range (tens to hundreds of kilometers) tracking of small fishes or other marine animals. Tracking is achieved by standard RAFOS triangulation using the arrival times of unique sound signals emitted by moored sources. The tag also records temperature and pressure. All functions of the tag are controlled by an application specific microchip. The collected acoustic and sensor data are stored in a non-volatile memory. A cylindrical hydrophone of 25.4mm length and 10.7mm diameter also serves as housing for all electronic components. Power is provided by 2 button cell batteries, which enable an active tag lifetime of approximately two years. Go to Introduction Much has been learned about the behavior of fishes during the past few decades through various kinds of data storage tags (DSTs), which were attached either externally to the back of the fish, or subc...

  Juniper Publishers -  Journal of Oceanography Abstract Many global aquatic ecosystems, particularly for those in high latitudes, are reported to be under pressure due to warming climate and anthropogenic interference. In this short article, we briefly discuss the two major environmental constraints for an aquatic ecosystem-streamflow and stream temperature, which haven't received enough attention thus with only sparsely available concurrent in-situ measurements across the globe. A novel numerical solution, i.e., the Dominant River-Tracing-based streamflow and Temperature (DRTT) model, is introduced, and it has been developed for the simulations of both daily streamflow and temperature along entire drainage networks for large regions, filling the data gap usually faced by aquatic ecologists. The DRTT model has been successfully applied in the study of freshwater salmon habitat and associated productivity in 1500 North Pacific Rim rivers. However, that study also indicated big...

  Juniper Publishers -  Journal of Oceanography Abstract This study investigates gonado somatic index, food and feeding habit of selected fish species of Lake Kalgwai Jigawa State, Nigeria. Samples of fish were collected every fortnight (July 2012-June 2013) at three major landing sites of the lake. The weight of each fish was recorded, gonads were removed, weighed and the gonadosomatic index (GSI) calculated. Stomach was also removed and the content analyzed using frequency of occurrence and point method. Result obtained reveals GSI to range from 2.39±0.08% in Nile perch Latesniloticus [ 1 ] to 5.92±0.29% in Nile tilapia Oreochromisniloticus [ 1 ]. The stomach content analysis in this study distinguished the fish species into two major groups; Latesniloticus, Mormyrusmacrophthalmus Günther, 1866 and Bayad bagrus bayad Forsskal [ 2 ] were observed to exhibit carnivorous feeding habits and feed predominantly on crustacean, fish, fish parts, mollusks, insects and ...

  Juniper Publishers -  Journal of Oceanography Abstract During our routine ecological survey conducted at Pulicat lagoon, the most diverse coelenterate belonging to 2 classes of scyphozoa ( Catostylus mosaicus, Acromitus flagellates, Cyanea capillata, Chrysaora hysoscella)  and hydrozoa ( Porpita porpita)  4 families ( Catostylidae, Cyaneidae, Pelagiidae and Porpitidae)  and 5 species were recorded. The  Catostylus mosaicus  was dominated at the Barmouth. A large amount of species occurred during the monsoon season 2013 to 2015. Cnidarians were washed ashore. During the study, the salinity levels were maximum value observed was 41 while the minimum value obtained was 38ppt. Hence, it is necessary to focus on conservation, monitoring and management strategies in places of Pulicat lagoon. Keywords:  Jelly fish; Pulicat lagoon; Distribution Go to Introduction Jelly fishes (Cnidaria), are well known bioindicators [ 1 ]. The increasing frequency of je...