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���Each pitch track takes less than 100 bytes, whereas transmitting just one of those calls as an audio clip would take about 8,000 bytes of data,��� Baumgartner said. The software can also be updated to identify more whale calls. Jellyfsh Populations Found to Cyclically Rise, Fall Over Decades Scientists have cast doubt on the widely held perception that there has been a global increase in jellyfsh over the past two centuries. Media and scientifc opinion for the perception of an increase in jellyfsh was evidenced by a few local and regional case studies in Japan and parts of the Mediterranean. However, the study, published in the Proceedings of the National Academy of Science, found that global jellyfsh populations undergo concurrent fuctuations with successive decadal periods of rise and fall, including a rising phase in the 1990s and early 2000s that has contributed to the idea that the jellyfsh population is rising globally. The previous period of high jellyfsh numbers during the 1970s went unnoticed due to limited research on jellyfsh at the time, less awareness of global-scale problems and a lower capacity for information sharing. While there has been no increase over the long term, the authors detected a hint of a slight increase in jellyfsh since 1970, although this trend was countered by the observation that there was no difference in the proportion of increasing versus decreasing jellyfsh populations over time. Shipping Lanes to be Adjusted to Protect Whales on California Coast The International Maritime Organization adopted three proposals to reduce incidents of ships striking whales on the approach to San Francisco Bay, the Santa Barbara Channel, and the Ports of Los Angeles and Long Beach. Vessels in these areas also travel through NOAA���s Cordell Bank, Gulf of the Farallones and Channel Islands national marine sanctuaries. Extending the three lanes will reduce interaction between ships and whales within the two national marine sanctuaries, where blue, humpback and fn whales feed and congregate. The proposed vessel lane changes in the Santa Barbara Channel and Channel Islands National Marine Sanctuary narrow the lanes��� width and shift the southbound lane 1 nautical mile north. Scientists Find Bipolar Distribution Of Marine Bacteria Scientists at the Marine Biological Laboratory have found bipolar species of bacteria that occur in the Arctic and Antarctic, but nowhere else, further discrediting the Baas-Becking hypothesis of ���everything is everywhere��� as far as bacterial distribution in the ocean. They also found fewer bipolar species than would turn up if marine bacteria were randomly distributed everywhere, suggesting there are forces in the ocean limiting the dispersal of bacteria. What these barriers may be is under investigation. ���Before, many people thought microbes distribute everywhere, so we don���t have to worry if some disappear locally,��� said Linda Amaral-Zettler, an author of the study published in the Proceedings of the National Academy of Science. ���But we are fnding that, no, there is a biogeography of very small organisms, and there may be consequences to that.��� n www.sea-technology.com FEBRUARY 2013 / st 83