[{"data":1,"prerenderedAt":184},["ShallowReactive",2],{"leaderboard-total":3,"spot-mackerel-island":9,"spot-seo-mackerel-island":149},{"entries":4,"total":5,"period":6,"type":7,"generated_at":8},[],0,"all_time","reports","2026-10-03T06:32:05.526386Z",{"id":10,"name":11,"slug":12,"latitude":13,"longitude":14,"description":15,"difficulty":16,"image_url":17,"status":18,"tide_constituents":17,"hazard_entries":19,"access_info_structured":90,"area_boundary":17,"routes":17,"created_at":96,"updated_at":97,"today_conditions":98,"today_verdict_view":119,"images":144,"submitted_by":145,"region_name":147,"verification_status":148,"verified_at":17,"disputed":128,"verifier_count":5,"last_verified_display_name":17},"31c6a453-3221-4e17-aa02-6dace8bb2374","Mackerel Island","mackerel-island",-42.040906,146.808732,"Mackerel Island is a small, uninhabited island off the north-east coast of Tasmania, part of a rugged archipelago in the Tasman Sea. Its rocky shoreline and kelp-fringed reefs offer temperate-water snorkeling amidst clear, cool waters. The surrounding underwater terrain features granite boulders, sponge gardens, and macro-algae beds that shelter a variety of marine life. Access is by private boat only, and conditions can be challenging with strong tidal currents, making it a spot best suited to experienced snorkelers seeking a wild, off-the-beaten-path adventure in Tasmania's pristine north-east waters.","advanced",null,"published",[20,24,28,33,36,39,42,45,50,53,56,60,63,66,69,75,78,81,84,87],{"name":21,"description":22,"severity":23,"season_start":17,"season_end":17},"Strong ocean currents","The exposed offshore position of The Canyon can experience strong tidal and ocean currents that may sweep snorkelers away from the site.","warning",{"name":25,"description":26,"severity":27,"season_start":17,"season_end":17},"Cold water temperatures","Tasmanian waters range from 11–18°C year-round, requiring a thick wetsuit or drysuit for comfortable snorkelling.","caution",{"name":29,"description":30,"severity":23,"season_start":31,"season_end":32},"Swell and surge","Large Southern Ocean swells can create powerful surge conditions around the walls and swim-throughs, especially in winter months (May–September).",5,9,{"name":34,"description":35,"severity":27,"season_start":17,"season_end":17},"Limited visibility","Visibility can vary dramatically with weather and plankton blooms; poor conditions may reduce visibility below 5m.",{"name":37,"description":38,"severity":23,"season_start":17,"season_end":17},"Strong Tidal Currents","Tidal flows around the island can be strong and unpredictable, especially between the island and the mainland coast.",{"name":40,"description":41,"severity":27,"season_start":17,"season_end":17},"Cold Water Temperature","Temperate Tasmanian waters remain cold year-round, typically 12–18°C, posing a risk of cold shock and hypothermia without adequate wetsuit protection.",{"name":43,"description":44,"severity":23,"season_start":17,"season_end":17},"Remote Location","The island is uninhabited with no facilities or emergency services nearby; boat access only and limited mobile reception.",{"name":46,"description":47,"severity":27,"season_start":48,"season_end":49},"Rough Seas & Swell","Exposed to the Tasman Sea, the island can experience sudden swell and choppy conditions, particularly in winter.",6,8,{"name":51,"description":52,"severity":27,"season_start":17,"season_end":17},"Rocky Shore Entry","No sandy beach; entry and exit are over slippery rocks and boulders, increasing risk of injury.",{"name":54,"description":55,"severity":23,"season_start":48,"season_end":32},"Strong Ocean Swell","The exposed eastern Tasmanian coast receives significant Southern Ocean swell, creating challenging conditions for snorkelers.",{"name":57,"description":58,"severity":23,"season_start":48,"season_end":59},"Exposed Open Ocean Swells","Black Jack Reef sits in Storm Bay, exposed to southerly and easterly ocean swells that can create dangerous surge and breaking waves over the reef.",11,{"name":61,"description":62,"severity":23,"season_start":31,"season_end":32},"Strong Wind & Weather Shifts","The Betsey Island Group catches strong winds from the Roaring Forties, which can change rapidly and make conditions unsafe for snorkelers.",{"name":64,"description":65,"severity":27,"season_start":17,"season_end":17},"Boat Traffic","The area is used by recreational and fishing vessels, posing a collision risk for snorkelers near the surface.",{"name":67,"description":68,"severity":23,"season_start":17,"season_end":17},"Isolated Location","The reef is offshore near Betsey Island with no immediate emergency services; self-rescue or support boat required.",{"name":70,"description":71,"severity":72,"season_start":73,"season_end":74},"Ocean Swell & Surge","Swell and surge can wrap around the point, creating strong unpredictable currents and turbulent conditions.","danger",1,12,{"name":76,"description":77,"severity":23,"season_start":73,"season_end":74},"Exposed Coastal Conditions","Exposed headland with no shore protection; strong offshore winds can arise quickly, making exit hazardous.",{"name":79,"description":80,"severity":27,"season_start":73,"season_end":74},"Slippery & Sharp Rocks","Sharp encrusting barnacles and bull kelp on intertidal rocks present a slip and cut hazard when entering\u002Fexiting the water.",{"name":82,"description":83,"severity":23,"season_start":31,"season_end":32},"Strong Ocean Swells & Surge","Exposed to the 'roaring forties' westerly winds, large swells and powerful surge can develop rapidly, especially in winter.",{"name":85,"description":86,"severity":23,"season_start":17,"season_end":17},"Unpredictable Currents","Strong, hard-to-predict currents run through the bight, particularly at depth and around the wreck.",{"name":88,"description":89,"severity":72,"season_start":17,"season_end":17},"Deep Water & Boat Access Only","Prime snorkeling\u002Fdiving sites require boat access; depths range to 40m+ with limited shore exit options.",{"directions":91,"parking":92,"facilities":93,"fees":94,"access_method":95},"Located off the north-east coast of Tasmania. Accessible only by private boat — launch from nearby coastal towns such as St Helens or Bicheno. No regular ferry or tour service runs to Mackerel Island. Navigate carefully as waters are exposed to the Tasman Sea.","Park at public boat ramps in St Helens or Bicheno. No parking available on the island itself.",[],"No fees for visiting, but boat launching fees may apply at local ramps.","boat","2026-07-27T02:57:33.656829Z","2026-07-27T02:57:33.656832Z",{"verdict":99,"evaluated_at":100,"models":101},"marginal","2026-10-03T02:21:45.919622Z",[102,109,113],{"model_name":103,"is_favourable":104,"value":105,"threshold":106,"unit":107,"operator":108},"Wind Speed",true,2.95,10,"kn","lte",{"model_name":110,"is_favourable":104,"value":5,"threshold":111,"unit":112,"operator":108},"Wave Height",0.5,"m",{"model_name":114,"is_favourable":104,"value":115,"threshold":116,"unit":117,"operator":118},"Visibility",2.39,2,"","gte",{"verdict":99,"rating":120,"evaluated_at":100,"generated_at":100,"source":121,"confidence":122,"visibility":125,"parameters":126,"models_passed":116,"models_total":31},"Fair","precomputed",{"level":123,"value":124},"Medium",75,{"score":115,"rating":17,"confidence":17},[127,129,132,136,141],{"name":110,"value":5,"label":17,"unit":112,"favourable":128,"score":73,"optimal_max":111,"marginal_max":73},false,{"name":130,"value":5,"label":17,"unit":131,"favourable":128,"score":73,"optimal_max":49,"marginal_max":74},"Swell Period","s",{"name":103,"value":133,"label":17,"unit":107,"favourable":104,"score":134,"optimal_max":106,"marginal_max":135},2.9546368,3,15,{"name":137,"value":138,"label":17,"unit":139,"favourable":104,"score":134,"optimal_max":31,"marginal_max":140},"Precipitation",2.1,"mm",20,{"name":142,"value":17,"label":143,"unit":117,"favourable":128,"score":73,"optimal_max":17,"marginal_max":17},"Tidal Phase","unknown",[],{"display_name":146},"Daniel","Tasmania","unverified",{"title":150,"description":151,"canonical_url":152,"og_image":153,"structured_data":154,"breadcrumbs":177},"Snorkeling Conditions at Mackerel Island - How's the Spot","Check snorkeling conditions at Mackerel Island, Tasmania. Fair conditions, waves 0.00m","https:\u002F\u002Fhowsthespot.com\u002Fspots\u002Fmackerel-island","https:\u002F\u002Fhowsthespot.com\u002Fog-default.png",[155,164],{"@context":156,"@type":157,"name":11,"description":158,"url":152,"geo":159,"address":161},"https:\u002F\u002Fschema.org","Place","Mackerel Island is a small, uninhabited island off the north-east coast of Tasmania, part of a rugged archipelago in the Tasman Sea. 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