WASHINGTON — Lawmakers are targeting invasive species —from ballast water dwellers in ships to hitchhikers on imported fruits and vegetables — in legislation this year, hoping to stem economic losses in Hawai'i and other states.

The issue will be showcased Tuesday when Sen. Daniel K. Akaka, the top Democrat on the Senate Energy and Natural Resources subcommittee on national parks, will lead a hearing on invasive species, with a focus on the problems at Hawai'i Volcanoes National Park.

Akaka, D-Hawai'i, introduced a bill last month to establish a $250 million cooperative grant program to fight invasive species on public and adjacent private lands. The grants would go to states, nonprofit organizations and tribes to assess, control and eradicate invasive species.

"Federal support to states to combat this problem at the ground level is crucial," Akaka said. "If ever there was a time to commit to defending the security of our domestic resources for the future, it is now."

Invasive species — defined generally as species alien to an area —are causing an estimated $138 billion in economic losses annually across the country.

In Hawai'i, the threats of invasive species have reached crisis proportions, according to the National Conference of State Legislatures.

"This is the invasive species capital of the world because we have so many endangered species that can be attacked," said Rep. Neil Abercrombie, D-Hawai'i, who is co-sponsoring several bills in the House to research and fight aquatic invasive species.

Hawai'i has more than 300 species on the endangered list, about one-quarter of the nation's endangered species. At the same time, the state has 47 of the world's 100 worst invasive species, according to the World Conservation Union.

"Any effort to help prevent invasive species from getting to Hawai'i, to help us deal with our response and control in dealing with those that are here, is very much appreciated," said Peter Young, chairman of the state Department of Land and Natural Resources. "We are looking for all the support we can get."

Abercrombie and Akaka aren't alone in their fight against the influx of foreign pests.

Sen. Dan K. Inouye, D-Hawai'i, is pushing legislation approved by the Senate Commerce Committee last month that would set uniform federal standards for ships to treat and discharge ballast water.

Ships not carrying cargo typically use large quantities of water for stability. That water often is laden with a variety of aquatic animals and plants. Once the ships take on cargo, they dump the water into local harbors and ports.

"Ballast water from ships is one of the largest pathways for the introduction and spread of aquatic invasive species," Inouye said. "The problem is not only from ballast water but also invasive species that travel on the hulls and other parts of ships."

The legislation also would authorize the Coast Guard to spend $25 million a year to fight invasive species.

But some attorneys general from Great Lakes states and environmental groups oppose the bill, saying it is not strong enough and would exempt too many vessels from the requirements.

Other legislation in the House and Senate would create an overall aquatic invasive species law that would take a tougher approach to ballast water regulation. The bills call for the identification of waterways that pose the highest risk for invasive species to enter the country.

The measures — co-sponsored by Akaka, Abercrombie and Ed Case, D-Hawai'i — also would establish a national system of ecological surveys for early detection and create 10 federal rapid response teams.

Another Abercrombie-Case bill calls for creation of an aquatic invasive species research program to find ways to prevent nonnative organisms from entering U.S. waters and to eradicate them when they are here.

And Case introduced a bill late last month to require the same or a greater level of federal inspection of all visitor and cargo shipments arriving in Hawai'i from domestic or foreign locations.

"My bill ... may be condensed into this simple statement, 'What is good for the U.S. Mainland should be good for Hawai'i,' " Case said. "Current federal inspections protect the U.S. Mainland from insect pests in Hawai'i, but Hawai'i, which has the greatest number of endemic endangered species of any state ... doesn't enjoy similar protection."