threats to marine species
HSI has campaigned for many years to highlight the threat faced by thousands of marine species including whales, turtles, dugong, seabirds, sharks and uncountable species of fish, from processes including shark control (beach meshing) nets, marine debris, ballast water, longline fishing, trawling and drift netting.
Shark Control Nets
Shark control programs are now in place in New South Wales (NSW), Queensland (QLD) and Western Australia (WA). These programs are designed to reduce the populations of potentially dangerous sharks and thereby lower the likelihood of a shark attack. Nets and / or baited drumlines are set off beaches along the coastline with the purpose of intercepting (and culling) sharks on their feeding and territorial runs up and down the coast. In NSW the shark control program relies solely on beach meshing to achieve this goal, QLD employs both mesh nets and baited drumlines and WA only uses baited drumlines. Contrary to popular belief neither act as a protective barrier for swimmers by enclosing the beach, and indeed many of the sharks killed in nets in NSW have been caught on the beach side of the net. For further information on HSI’s work on shark control programs click here.
Marine debris is defined as the pollution by human generated objects or as anthropogenic solid matter in the sea. The main components of marine debris are plastics and other synthetic waste such as glass and metal. It has been estimated that Australia alone produces almost 1 million tonnes of plastic each year and world wide estimates put the amount of debris entering the world' s oceans annually at 7 billion tonnes.
Marine debris is then subject to the ocean currents and can spend several years at sea before being washed up many thousands of miles away from the source. This makes marine debris a global concern as well as a national one. For further information on this key threatening process click here.
Ballast water usually consists of coastal water that is taken on board a ship at port, for the stability of the unladen vessel during its voyage. This ballast is then discharged and exchanged for cargo at the port of destination. The sediment, which has settled at the bottom of the tanks, is physically shovelled over the side of the ship directly into the ocean.
Ballast water is different from bilge water which is a combination of rain water, sea water, waste matter and seeped oil from below deck, and is usually discharged at port in a controlled manner. The difference between bilge water and ballast water is that bilge water is considered to be abiotic whilst ballast water is biotic (contains living organisms). For further information on this key threatening process click here.
Longline fishing is a technique used to target fish in open waters, including those that live near the sea floor. A longline includes a main fishing line up to 100 kilometres in length, with secondary lines branching off it; each set with hundreds of thousands of barbed, baited hooks. This technique is used in the waters off the United States (e.g. Atlantic coast and Hawaiian waters), South America, Australia, New Zealand and southern African countries.
Longlining is used to target fish species such as tuna, swordfish and Patagonian toothfish but indiscriminately kills millions of other species including sharks, turtles and seabirds that get caught 'incidentally' on the hooks. For further information on this key threatening process click here.
For further information on this key threatening process click here.