03-12993. Hydrilla; Availability of an Environmental Assessment

AGENCY:

Animal and Plant Health Inspection Service, USDA.

ACTION:

Notice of availability and request for comments.

SUMMARY:

We are advising the public that an environmental assessment has been prepared by the Animal and Plant Health Inspection Service relative to the control of the aquatic weed hydrilla (Hydrilla verticillata). The environmental assessment considers the effects of, and alternatives to, the release of the nonindigenous leaf-mining flies Hydrellia pakistanae Deonier and H. balciunasi Bock (Diptera: Ephydridae) as biological control agents to reduce the severity of infestations of hydrilla in the continental United States. We are making this environmental assessment available to the public for review and comment.

DATES:

We will consider all comments that we receive on or before June 23, 2003.

ADDRESSES:

You may submit comments by postal mail/commercial delivery or by e-mail. If you use postal mail/commercial delivery, please send four copies of your comment (an original and three copies) to: Docket No. 03-053-1, Regulatory Analysis and Development, PPD, APHIS, Station 3C71, 4700 River Road Unit 118, Riverdale, MD 20737-1238. Please state that your comment refers to Docket No. 03-053-1. If you use e-mail, address your comment to [e-mail]. Your comment must be contained in the body of your message; do not send attached files. Please include your name and address in your message and “Docket No. 03-053-1” on the subject line.

You may read any comments that we receive on the environmental assessment in our reading room. The reading room is located in room 1141 of the USDA South Building, 14th Street and Independence Avenue SW., Washington, DC. Normal reading room hours are 8 a.m. to 4:30 p.m., Monday through Friday, except holidays. To be sure someone is there to help you, please call [phone] before coming.

APHIS documents published in the Federal Register, and related information, including the names of organizations and individuals who have commented on APHIS dockets, are available on the Internet at http://www.aphis.usda.gov/​ppd/​rad/​webrepor.html.

FOR FURTHER INFORMATION CONTACT:

Dr. Tracy A. Horner, Ecologist, Environmental Services, PPD, APHIS, 4700 River Road Unit 149, Riverdale, MD 20737-1236; [phone].

SUPPLEMENTARY INFORMATION:

Background

The Animal and Plant Health Inspection Service (APHIS) is considering an application by a researcher at the U.S. Army Engineer Research and Development Center in Vicksburg, MS, for a permit for the continued release of the nonindigenous leaf-mining flies Hydrellia pakistanae Deonier and H. balciunasi Bock (Diptera: Ephydridae) in the continental United States. These agents, which have previously been released in the United States, would be used by the applicant for the biological control of the aquatic weed hydrilla (Hydrilla verticillata (L.F.) Royle) (Hydrocharitaceae) in new areas infested with hydrilla.

Hydrilla, which is native to the warmer areas of Asia, was first discovered in the United States in 1960. A submersed aquatic plant, it has the ability to multiply profusely, producing long, thick stands. It has become a major nuisance in many aquatic systems, displacing native aquatic plants such as pondweeds and eel grass, causing navigational interference, hindering waterflow, and detracting from recreational use of water bodies.

Four types of controls are currently being used to limit the spread of hydrilla: Chemical, mechanical, cultural/physical, and biological. Chemical controls include various herbicides. Mechanical controls include hand cutting/pulling, cutting, harvesting, and grinding. Cultural/physical controls include dredging/sediment removal, drawdown, benthic barriers (covering plants with a growth-inhibiting substance), and shading/light attenuation. Biological controls include, in addition to the two species of flies under consideration in the present environmental assessment, two weevil species.

The efficacy of these methods varies, and environmental and economic impacts may also limit the utility of some of them. The herbicides employed as chemical controls are safe when used according to their labels but are broad spectrum in their plant-species response and may affect non-target submersed vegetation. Hand cutting/pulling, although labor intensive, can be very effective in localized areas, while cutting, harvesting, and grinding are all considered cosmetic, nonselective, and short-term solutions. Due to its high cost, environmental impacts, and the problem of sediment disposal, dredging is considered a multipurpose lake remediation technique and should not be done solely for aquatic plant management. Drawdown, which involves removing the water of a lake to a given depth and holding it at that level for at least a month to provide complete drying, is only effective for 1 to 2 years when applied to hydrilla. Benthic barriers are too expensive for widespread use and also heavily affect benthic communities. Shading or light attenuation (controlling plants by light reduction) has only limited applicability.

The biological control agents H. pakistanae and H. balciunasi, which have been released previously in several States, have the potential to reduce the severity of infestations of hydrilla in other areas of the continental United States. H. pakistanae and H. balciunasi are flies in the family Ephydridae. Female Hydrellia spp. lay their eggs on hydrilla, and after several days, the eggs hatch into larvae. The larvae of both species damage hydrilla plants by mining leaves. APHIS has completed an environmental assessment that considers the effects of, and alternatives to, the release of H. pakistanae and H. balciunasi into the environment as biological control agents for hydrilla.

APHIS' review and analysis of the potential environmental impacts associated with releasing H. pakistanae and H. Balciunasi into the environment are documented in detail in an environmental assessment entitled “Field Release of the Nonindigenous Leaf-mining Flies Hydrellia pakistanae Deonier and H. balciunasi Bock (Diptera: Ephydridae), for Biological Control of Hydrilla verticillata (L.F.) Royle (Hydrocharitaceae)” (April 2003). We are making this environmental assessment available to the public for review and comment. We will consider all comments that we receive on or before the date listed under the heading DATES at the beginning of this notice.

The environmental assessment may be viewed on the Internet at http://www.aphis.usda.gov/​ppq/​ by following the link for “Document/Forms Retrieval System,” then clicking on the triangle beside “6-Permits-Environmental Assessments” and selecting document number 0035. You may request paper copies of the environmental assessment by calling or writing to the person listed under FOR FURTHER INFORMATION CONTACT. Please refer to the title of the environmental assessment when requesting copies. The environmental assessment is also available for review in our reading room (information on the location and hours of the reading room is listed under the heading ADDRESSES at the beginning of this notice).

The environmental assessment has been prepared in accordance with: (1) The National Environmental Policy Act of 1969 (NEPA), as amended (42 U.S.C. 4321 et seq.), (2) regulations of the Council on Environmental Quality for implementing the procedural provisions of NEPA (40 CFR parts 1500-1508), (3) USDA regulations implementing NEPA (7 CFR part 1), and (4) APHIS' NEPA Implementing Procedures (7 CFR part 372).

Done in Washington, DC, this 16th day of May 2003.

Kevin Shea,

Acting Administrator, Animal and Plant Health Inspection Service.