Invasive Species Preventing invasions is critical, as controlling one is nearly impossible.

The Problem

The unchecked spread of aquatic invasive species (AIS) is one of the most significant threats to the Great Lakes ecosystem. Invasive species are not native to the ecosystem, and by definition cause harm to human health, the environment and the economy. Zebra and quagga mussels now coat the floor of Lake Michigan, Asian Carp are infiltrating rivers and are at the doorstep of Lake Michigan, and efforts to control sea lamprey cost $16 million per year with limited success. The discovery of the Zebra Mussel showed that prevention is critical, as controlling an invasion is nearly impossible.

The unloading of ballast water–meant to balance a ship’s weight–is a main source of introducing invasive species into the Great Lakes. One study estimated ~$200 million is lost annually due to invasions caused by shipping, and ballast discharge is expected to increase with a boom in liquid natural gas exports. The Vehicle Discharge Act, under consideration by Congress, would further weaken ballast water control by transferring regulatory authority from the EPA to the Coast Guard, which lacks water pollution expertise. It would also create ballast exemptions from the Clean Water Act that are intended to protect water quality, public health, and native species.

Zebra mussel
Zebra mussel

Fast Facts

The estimated damage from invasive species worldwide totals more than $1.4 trillion, or five percent of the global economy.

Invasive species create a loss of agricultural productivity—about one-fourth of U.S. agricultural gross national product is lost each year to foreign plant pests and the costs of controlling them.

The annual U.S. cost from invasives was estimated to be $120 billion, with more than 100 million acres affected (i.e., about the size of California)

Invasive species are the second leading cause of animal population decline and extinction worldwide. Invasive species have contributed directly to the decline of 42% of threatened and endangered species in the United States.


Each state has the ability to enact laws and rules related to invasive species within its boundaries and to define those species. Below are four strategies states have employed to address AIS and ballast water issues.

  1. Formal or informal legislative caucuses, such as the Ohio Lake Erie Caucus, offer dedicated attention to water issues, including AIS.
  2. Coordinated monitoring between states coupled with increased management funding both federally and in state budgets.
  3. Updating and strengthening state Aquatic Invasive Species Action Plans
  4. Increased awareness of AIS and the importance of strong ballast water standards for ecosystem and economic health.

Sample Policy

National Sea Grant Law Center has a model state watercraft inspection law and a comparison of all existing state laws and the model here

Invasive Species

Science and Reports

Building Consensus in the West: Developing a Model Legal Framework for Watercraft Inspection and Decontamination Programs – National Sea Grant Law Center, 2015

The National Sea Grant Law Center produced this report on western state watercraft inspection and decontamination (WIP) programs to stop aquatic invasive species. A companion report provides comparisons of all 50 states, model state legislation, and multi-state reciprocity recommendations.

Invasive Species Control: A Comprehensive Model State Law -- ELI, 2004

This companion publication to “Halting the Invasion” provides the statutory framework for a comprehensive state program to detect, control, and manage the threat of invasive species across all taxa. The model law has been introduced by legislators in California and used to support reform efforts in the Caribbean.

Status and Trends in State Invasive Species Policy -- ELI, 2010

This report reviews state laws and policies of 11 states from 2002 to 2009.

Halting the Invasion: State Tools for Invasive Species Management– Environmental Law Institute(ELI), 2002

This seminal study analyzes the existing state laws and regulations that address invasive species, provides policy-makers with information on how to strengthen invasive species control programs, and includes an appendix of state-specific invasive species laws and regulations. The recommendations have been incorporated into state invasive species management plans in New Jersey and in other states.


Recent News