More Park Facilities Reopen During May 2013
Watch Hill and Sailors Haven marinas open May 10. Limited ferry service from Sayville to Sailors Haven resumes May 13 and ferries from Patchogue to Watch Hill start on May 18. Remaining park facilities to reopen by May 25, 2013. More »
Mosquito Monitoring & Management
The Fire Island National Seashore mosquito surveillance and management program is the foundation for mosquito monitoring programs throughout the National Park Service. It was first implemented in 1998 in response to public concern over Eastern Equine Encephalitis (EEE). In 1999, when another mosquito-borne disease - West Nile virus (WNV) - was discovered in the New York metropolitan area, the program expanded. The goal of this program is to reduce human health risk from mosquito-borne diseases while adhering to the NPS legal mandate to protect the natural resources of the park.
The Fire Island monitoring program focuses on the collection and analysis of both salt marsh mosquitoes and freshwater mosquitoes. The eastern salt marsh mosquito, Aedes sollicitans (also classified under the genus Ochlerotatus by some), is a potential vector for EEE. Although this mosquito can also transmit WNV, it has not been found to be a major concern as it relates to this disease. Salt marsh mosquitoes lay their eggs on mud flats of the upper salt marsh, which develop in small puddles during lunar high tides. Fire Island National Seashore's salt marshes are located mainly on the bay side of the eastern end of Fire Island and along the shoreline of the William Floyd Estate. Freshwater mosquitoes in the genus Culex, including the common house mosquito, are competent vectors of WNV. There are species of salt marsh mosquitoes in this genus, but most of the Culex species found on Fire Island are freshwater mosquitoes. These freshwater species lay their eggs in standing water with high organic matter content, sometimes taking advantage of poorly maintained bird baths, trash cans, old tires, and other artificial breeding containers.
Stage 1 - Surveillance and Education
Fire Island's mosquito management program begins with education (brochures, bulletin board announcements, interpretive programs, web site, etc.), to inform the public about mosquitoes, their role in natural systems, the potential for disease transmission, and the park's surveillance and management program.
Fire Island National Seashore also conducts a sanitation program to reduce artificial Culex larval habitat (e.g., by filling ruts in sand roadways that retain standing water for longer than 2 or 3 days, by draining garbage cans or removing other artificial sources of standing fresh water, etc.) on park lands.
Basic monitoring consists of passive surveillance for dead birds, monitoring of larval and adult mosquitoes (especially adult monnioring using CO2-baited CDC miniature light traps and gravid traps), and viral testing.
The park's mosquito trapping season begins the first week of June and terminates by the middle of October. Twelve mosquito traps were initially maintained at five or more different study sites in the park. Since 2008, eighteen (18) traps have been maintained throughout the park at seven different sites.
Study sites chosen to monitor mosquito populations are usually the Fire Island Lighthouse Tract (near the community of Kismet), Saltaire (maintained by the Village of Saltaire), Sailors Haven/Sunken Forest, the Carrington Tract (beside the community of Fire Island Pines), Watch Hill, the Otis Pike Fire Island High Dune Wilderness, and the William Floyd Estate. Additional traps are also placed when a positive sample is collected.
The monitoring program uses two types of traps to collect mosquitoes: CDC gravid traps, intended to collect egg-bearing Culex species, and CDC light traps, intended to collect host-seeking adult female mosquitoes of all species.
In 2010, the highest light trap total was an estimated 25,142 mosquitoes obtained from a trap located in the Fire Island Wilderness Area on August 31. The highest single day count to date, collected on the night of September 17, 2006 from a CDC Light Trap in the Fire Island Wilderness at Hospital Point, was an estimated 54,000 mosquitoes. Given that the trapping periods are about 16 hours, this calculates to a rate of 3,375 per hour, 56 per minute or about 1 per second!
The highest gravid trap total in 2010 was obtained from the Watch Hill West trap, with 437 mosquitoes collected on July 26. (About 5,425 mosquitoes were collected from this site on 6/25/2007). The average for this site was 61 mosquitoes, while the Fire Island Lighthouse/Kismet gravid trap average was 1, Saltaire averaged 0, Sunken Forest was 4, Fire Island Pines/Carrington was 1, Wilderness Visitor Center was 24, and the William Floyd Estate averages were 0 and 2.
Of the 40 species of mosquitoes recorded in Suffolk County, at least 25 different species have been found within Fire Island National Seashore.
Stage 2 - Detection and Public Notification
When certain criteria are met (over 1,000 female mosquitoes in a CO2-baited CDC light trap from Fire Island, or over 100 individual mosquitoes in a trap from the William Floyd Estate; or detection of WNV or EEE virus in birds, mammals, or mammal-feeding mosquitoes on Fire Island or at mainland Long Island sites within five miles of Fire Island or the William Floyd Estate), the Mosquito Action Plan is elevated to Stage 2, Detection and Public Notification.
With the exception of 2007 and 2011, evidence of WNV-infected mosquitoes has been detected within the boundaries of the park every year since 2000, when it was detected in the community of Saltaire.
If WVN or EEE is detected within the park, visitors and residents will be notified about mosquito densities, the possibility of viral infection, and self-protection methods to minimize the number of mosquito bites. Arrangements are finalized for pesticide application in case conditions warrant such intervention. Larval management in artificial sites will be intensified and surveillance will continue or may be expanded.
Stage 3 - Mosquito Management
This stage is triggered by the detection of of disease in more than one "pool" of mosquitoes (a pool is defined as a sample of up to 50 mosquitoes taken from a single trap) or by detection of disease in both mosquitoes and birds, or in increasing numbers of infected birds.
Action at Stage 3 could take several forms: local application of adulticide or larvicide, and/or closing areas of the park to the public. Regardless of what management action is taken, current concerns about disease transmission will be communicated to the public.
Because of its effect on the environment, especially on fisheries and non-target species, spraying is the action of last resort. However, after consultation with Suffolk County Vector Control, New York State Health Department, the Center for Disease Control (CDC), the USGS Research Center and experts from other appropriate institutions or universities, the park may authorize spraying when specified levels of infection are detected.
Is It Safe To Spray?
The use of pesticides within a National Park Service area are required to be in accordance with Servicewide policies as found in NPS-77 (Natural Resources Management Guidelines).
An Integrated Pest Management (IPM) Plan for Fire Island National Seashore was prepared in late November 2006 to provide basic low-risk pest management guidelines to help protect park resources (preserve the stored cultural museum resources and park structures, conserve the park grounds), and to protect the health and safety of people.
All pesticides used within Fire Island National Seashore must be applied by or under the direct supervision of a State of New York certified pesticide applicator. All pesticides used in the park by residents, contractors, special use permittees, agricultural issues, or non-NPS personnel must conform to NPS policies and guidelines, and be approved before use. The goal is to use low-risk pesticides, if necessary, that will accomplish desired objectives.
A long-term Mosquito Management Plan is being jointly developed by Suffolk County, New York and Fire Island National Seashore, and will be implemented when the joint plan is finalized. Until then, the park staff utilizes the park's mosquito surveillance and management protocols currently in existence.
For More Information
Learn more about Fire Island National Seashore's mosquito monitoring program. The National Park Service's recent reports for Fire Island National Seashore are available on-line:
For further information concerning West Nile virus and other vector-borne diseases, visit the National Park Service's Public Health Program and the U.S. Centers for Disease Control: www.cdc.gov/ncezid/dvbd/.
Under a letter of authorization from the National Park Service, Suffolk County Department of Public Works, Division of Vector Control conducts scheduled spraying for adult mosquitoes in several of the towns and villages within the boundaries of Fire Island National Seashore. Individual residents may request that their property be excluded from nonemergency treatments.
A series of Science Synthesis Papers was published in 2005 to support the preparation of a General Management Plan for Fire Island National Seashore.
Did You Know?
Park rangers and certain volunteers provide roving patrols and interpretation on horseback on Fire Island. More...