Acts of piracy at sea are on the rise but there is little evidence to support concerns from some governments and international organizations that pirates and terrorists are beginning to collude with one another, according to a RAND Corporation study issued today.

Piracy - boarding a ship to commit theft or another crime - totaled 2,463 actual or attempted incidents between 2000 and 2006, according to the report. The overall problem is almost certainly even greater than the figures suggest as researchers suspect nearly half of all piracy attacks are not reported, usually because of fears about subsequent investigation costs and increases to insurance premiums.

The objectives of the two crimes remain different -- piracy is aimed at financial gain while the goal of terrorism is political. Although both events are increasing, piracy is growing much faster and remains far more common than seaborne terrorism, according to the report.

Peter Chalk, author of the study and a senior political scientist at RAND, a nonprofit research organization, said the study's findings suggest U.S. policymakers focus too much on responding to worse-case terrorist scenarios rather than crafting policies to combat lower consequence (but more probable) attacks that could strike cruise ships or passenger ferries. Just as seriously, the U.S. government has paid comparatively little attention to combating piracy, despite its proven cost in terms of human lives, political stability and economic disruption.

"The maritime environment will likely remain a favorable theater for armed violence, crime and terrorism given its expanse, lack of regulation and general importance as a critical conduit for international trade," said Chalk. "While there is no quick fix for eliminating all of this, we can rationally manage the threats within acceptable boundaries."

The number of piracy incidents worldwide increased 68 percent from 2000 to 2006, compared to the previous six year period, according to the study. Meanwhile, the period saw only a modest spike in terrorist attacks and plots at sea, including the 2004 bombing of the Philippine ship SuperFerry 14 that killed 116 people.

Piracy remains greatest in Southeast Asia, especially around the Indonesian archipelago, the report said. The region accounted for nearly a quarter of all piracy incidents recorded during 2006. Other high-risk areas include the waters off Bangladesh, Somalia, the Gulf of Aden/Red Sea, Nigeria, Tanzania and Peru, which collectively accounted for the bulk of remaining incidents that year.

Chalk said that a number of factors have contributed to the recent growth of piracy, including: lax port security and ineffective coastal surveillance; massive growth in commercial maritime traffic; heavy use of narrow and congested chokepoints, such as the Strait of Malacca; and competing resource requirements stemming from heightened national and international pressure to enact expensive, land-based homeland security systems following the Sept. 11 terrorist attacks.

In addition, the lingering effects of the Asian financial crisis that spurred falling wages, higher food prices and job losses in the late 1990s, directly contributed to the growth of piracy in and around Indonesia by creating an incentive for many to engage in maritime (and other types) of crime.

Maritime terrorism -- attacks against vessels, sea platforms, ports or other coastal facilities -- has also experienced a modest increase, particularly over the past six years when several attacks and plots have been attributed to al-Qaeda and affiliated jihadist networks. These incidents have raised concerns in the West, especially in the United States, that terrorists are now actively seeking to extend their operational reach beyond land-based attacks, Chalk said.

While the Bush administration has been at the forefront of efforts to upgrade global maritime security through such initiatives such as the Container Security Initiative and the International Ship and Port Facility Security Code, these measures are limited in scope and lack a definitive means to evaluate and audit their overall utility and transparency, Chalk said.

The study concludes that there are at least four policy-level contributions that U.S. policymakers can make to help better safeguard the world's oceans: