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Usa. Speed limit for ships: the noise alters the communication of killer whales

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Usa. Speed limit for ships: the noise alters the communication of killer whales
The limits of speedà for ferry, cargo and cruise ships that always più many flock to Puget Sound, a sea channel is situated in front of Seattle, in an arm of sea that extends to Vancouver and Vancouver Island, or route is very popular. All to save local population of orcas, a communityà sedentary and feeds mainly salmon and fish of small and medium-cut, instead of relatives that ply oceans. The cetaceans have been reduced to 78 unità.L'experiment &is in place by August, and you protrarrà until 6 of next October, under guidance of Vancouver Fraser Port Authority. The limit "suggested" to ships that pass in 'Haro Strait, l' area where killer whales spend especially in summer months, is 11 nautical miles, compared to example 13 medium in which y normally pass bulk carriers and 18 of container. The first purpose of slow-down is to check to see if a similar slowdown sarà able to reduce noise vessels produce sott'water: a roar that disturbs communications of great whales, which emit an innumerable varietyà of sounds to communicate with each or over great distances, respective positions and presence of food.

killer Whales in Salish Sea

Share   The authoritiesà port have found l'agreement with sixty owners who normally transit through strait (where y spend an average of 95 ships per week): among se are Washington State Ferries and cruisers of Holland America. Also vessels of a smaller size, such as those that carry out cruises local sightseeing or whale watching, were asked to reduce speedà. The percentage of membership'experiment è so far been more than 50 per cent of ships passing through, with spikes up to 70 and falls down in weeks in which presence of strong tidal currents, attached to a slow "default" has induced some operators to not reduce more than speedà of transit, not to put at risk respect of departure and arrival times, with consequent increase of costs."We are very happy with level of participation, explained Orla Robinson, progran manager of implementation of 'habitat, and conservation of cetaceans, created by Vancouver Fraser Port Authority, which has launched project aimed at persuading collective of owners and economic operators localized, so thaté is reduced l' overall impact of activity; linked to navigation on killer whales of Salish Sea between Washington State and British Columbia in canada. A portion of sea where it lives a second communityà of cetaceans. Awards più to North, between coast of canada and north-eastern shore of Vancouver Island, family enjoys better health, since its population is increased to two and a half times, up to 300 unità, in 40 years. Vancouver offers 500 canadian dollars to each ship that slows down, as well as granting discounts on port charges to ships, less noisy, and to those who install technologies aimed at reduction of decibel. "noise può interfere with activitiesà vital of killer whales, " explains Marla Holt, a marine biologist who studies noise emissions of large aquatic mammals at Northwest Fisherise Science Center in Seattle - such as those of eating and of communicate to be able to live toger as a family group. Studies have shown that whales in general and killer whales in particular spend more time on move, and spend less to search for food, in presence of intense boat traffic. And that ir calls are getting moreù strong l'increase of underwater noise". 

Whale watching in Salish Sea

Share   When looking for one of ir usual prey, Chinook salmon, killer whales emit a sound similar to a click, and remain in expectation of 'echo, return, which comes from fish that is situated in vicinity. "If background noise is detrimental to ir hunting technique, " explains Scott Veirs, a marine biologist who conducts studies on response of killer whales to low speedà of ships, for and on behalf of center for study independent of 'activitiesà port vancouverina -, habits of killer whales could change: may emit sounds, more noisy, or even stop altoger".  A'or companies; scientific studierà that different behaviour of cetaceans in area.Ongoing studies will also serve to supply elements to National Oceanic and Atmospheric Administration (NOAA) Fisheries, which is considering l'possibility of establishing a'a protected area for killer whales off coast of San Juan Island. A'area, where ships would be forbidden to transit. A'idea that has obviously put on opposite sides-industry and environmentalists. The limit of speedà, it seems to propose as a possible compromise


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