Records of jellyfish swarms over the past 200 years show that jelly populations rise naturally every 12 years, remain stable four or six years, and then subside again. Since the turn of the century, however, the pattern has been broken and their numbers have continued to escalate year after year.

But since the turn of the century, the biomass of large fish in many oceans has dropped dramatically as well.  In the waters off the coast of Namibia, which used to be one of the richest fishing grounds in the world, has dropped to 3.2 million tons, while the biomass of jellies has increase to 12.5 million tons. The reason: overfishing by the huge fish factory ships of the European Union.

Most jellyfish are really dangerous to humans, but there are a few that can administer excruciatingly painful stings. The mauve stinger is the most common of these, and has resulted in closed beaches all along the Atlantic coast of Europe and in the Meditteranean Sea. It is the same jelly that killed 120,000 adult salmon in Ireland's only fish farm in 2007.

The box jellyfish, which is common inthe seven seas bounded by Northern Australia, Thailand, and the Phillipines, is listed (for good reason) as the world's most venomous animal. It kills more people each year than all sharks combined - which are rapidly becoming extinct anyway. The box jelly is responsible for an average of one Australian death per year, and an estimated 40 or more in the rest of its range.

Paul Watson of the Sea Shepherd Conservation Society has been trying for years to help endangered sea life and in 2002 decided to take the law into its own hands in an effort to limit the harmful effects of long-lining. He established an active enforcement agency to intervene against illegal fishing activities in both International and territorial waters of some states, such as the Galopagos and Colombia's Malpelo Island National Park.

The use of long-lines in international waters is not illegal in itself. However, if the lines take an endangered or threatened species, they become illegal and the Sea Shepherd's enforcement vessel, the R/V Farley Mowat is quick to respond.

Since 2002, the Sea Shepherd crew has confiscated an illegally set Costa Rican 18.6 mile line in Guatemalan waters, numerous lines from the Marine Sanctuary of Cocos Island; 7.5 miles of long-line from Galapagos National Park; 37.3 miles of line in the waters between Tahiti and New Zealand; over 60 miles of illegally set long-line from another location, releasing four sea turtles, sixty-seven sharks, and more than a hundred large fish.

They have confiscated long-lines near the Cook Islands and south of Hawaii; intervened and confiscated lines near the Galapagos, around Colombia ’s Malpelo Island and in the Galapagos Corridor between the Galapagos and Panama; confiscated a 4km Uraguayan toothfish long-line inside the Australian Antarctic Territorial waters.

In all, they have confiscated thousands of miles of lines, some as short as 0.5 km (0.3 miles), others as long as 100km (62 miles). What does it do with the seized fishing equipment? The monofilament line is incinerated on board ship. The twine line is kept and utilized for tie-downs and for knot braiding on the ship’s rails. The hooks and swivels are kept for display purposes and the lead weights are melted down for dive weights.

One of the most innovative actions of the Sea Shepherds was their deployment of 16 net ripper devices on the Tail of the Grand Banks of Newfoundland to cut and damage bottom trawl nets after the Canadian Government ignored their calls for a two decade moratorium on fishing on the Newfoundland Grand Banks in order to re-establish the collapsed cod populations. The rippers, made of concrete blocks, not only protect the habitat but enhance it by providing shelter for many species of sea life, and an ideal base for jellyfish polyps to mature into countless more jellies to join in the fight against overfishing.