*********************************************************************
In 2003, George Hutmacher of Salem, who owns Hut Harbor Airboats, has proposed establishing airboat rides in Yaquina Bay, Siletz Bay, Siuslaw Estuary (Florence), and Coos Bay (Gallob 2003b, Dillman 2003). It is possible that he has also sought moorage at other Oregon estuaries. He has rides along the Willamette River, near Salem.
Lincoln City rejected the airboat proposal in 2003. On 24 June 2003, the Port of Newport Commission met and denied giving moorage to Hut Harbor Airboats. I do not know if the City of Coos Bay or the City of Florence and Port of Siuslaw have allowed Hutmacher's request.
Commercial airboat rides have not been previously available in the past, to my knowledge, in any Oregon estuaries.
The purpose of this web page is to examine some of the controversies about airboat operation in other areas, especially the noisiness of airboats and their disturbance of residents, other water users, and wildlife.
*********************************************************************
The source of the following is mostly from the Airboat FAQ (1998) and AR-502 of the American Airboat Corporation, both include photos of airboats.
An airboat is a boat that is powered by large propellers in the air. They do not have a propeller in the water, so they can go into very shallow water or even on dry land. Airboats are all-terrain vehicles (ATV) that can travel on water, grass, marsh, mud, tundra, dry ground, log jams, small boulders, roads, snow and ice. Accordingly, they are sometimes classed with Off-Road Vehicles (e.g., see Big Cypress National Preserve ORV Management plan that includes airboats). Some airboats are capable of 45 mph on land, 60 mph on water, and 70 mph on ice.
Most airboats now use automotive (not aircraft) engines, with 8 ft by 20 ft airboats by Trail Boss and American Airboat Corporation using 454 and 502 cu. inch V8 Chevy engines, respectively. Hutmacher's airboat at Salem in 2002 had a 454 cu. inch engine.
A hovercraft is similar to an airboat in that both are powered by propellers in the air. The American Airboat Corporation Airboat FAQ states: "The airboat differs from the hovercraft with respect to the amount of air cushion. An airboat may route some air from a supercharger to a cavity beneath the hull to reduce surface friction. The air cushion, however, is infinitesimal compared to a hovercraft which often routes half of its power to the task of generating an air cushion."
====================================================================
Airboats appear to be much more popular than hovercraft, since I have found more information about airboats than hovercraft. However, airboats appear to have created many more complaints, so there are more restrictions on airboats. Both airboats and hovercraft can travel on estuarine mudflats or go into very shallow water where other watercraft can not. Consequently, depending upon how they are operated and where they go, both have the potential to disturb wildlife.
*********************************************************************
Noise levels depend upon how far away from the noise source the noise level is measured. Airboat noise measured in decibels will be highest next to an airboat. For example, for a 14 ft boat with a 30-horsepower Mercury outboard engine, Rodgers and Schwikert (2002:217) measured a noise level of 87 dBa (decibels) at 10 m (33 ft) and 66 dBa at 50 m (164 ft)
One indicator that airboats are noisy is that airboat tours routinely provide earplugs to their customers (e.g., search Google at http://www.google.com/ for "airboat earplugs"). Hutmacher also gave earmuffs to passengers on his airboat in 2002 at Salem. On charter boats that I have been on in Oregon, earplugs were not provided, and, in my opinion, were not necessary.
In the following entries, the estimated noise levels of airboats are discussed.
Search for "Gibbs" at Minutes: State of North Carolina Board of Commissioners, County of Henderson (19 May 1999. Her comments [boldface added below]:
"Margaret Gibbs, 155 Carrie Lane, Fletcher, NC. Ms. Gibbs stated she was a licensed audiologist in North Carolina and also a property owner along the French Broad River. She expressed concern about the activities of the commercial airboat along the French Broad River. Ms. Gibbs had measured the noise of the airboat both with an analog and a digital sound level meter, both of which were calibrated. She had also measured the noise levels of aircrafts at the Asheville Airport because she lived very close to the airport also. As a reference she had measured the aircrafts passing over the same location from 56 to 74 dba [decibels] depending on the type of aircraft. The measurements that she had gotten from the airboat had been 102 to 104 dba. The sound level meters measure in units called decibels. A decibel scale is not linear. ... In the Henderson County Noise Ordinance, daytime noise is limited to 88 dba and the airboat was approximately sixteen times greater than this. The dba refers to the weighting scale and the weighting measures used for sound frequencies in the five hundred to ten thousand hertz ranges. This is the range where the human ear is the most sensitive. Ms. Gibbs distributed information that showed some everyday sound levels. Normal conversation speech from five feet away is around 55 dba. The beginning of OSHA regulations start at 85 dba, a chain saw is 100 dba and a helicopter is 105 dba. Ms. Gibbs read a few excerpts concerning OSHA regulations for businesses. All continuous, intermittent, and impulsive noise between 80 and 130 dba must be included in the exposure assessment which meant it had to be documented. Employers must offer hearing protectors to workers exposed to above 85 dba and all must be given a variety of protectors from which to choose. Training sessions must be given at least annually to workers exposed to above the 85 dba. Employers must provide base line audiograms within the first year of an employee's exposure to 85 dba and above and annual audiograms thereafter. OSHA has regulations to protect employees so was it right for people living along the French Broad River to be exposed to these levels at even higher levels addressed by OSHA without their consent or without compensation. No hearing protection is provided to all those people on the riverbank. ... Commissioner Moyer asked Ms. Gibbs where she took her audiology measurements. Ms. Gibbs replied she took them from her property along the French Broad River in a field close to the river."
[My comments: The distance between the airboat and where she measured the sound level is not given but is important because the sound level is reduced with distance. Nonetheless, her testimony shows that sound levels of the commercial airboat were 102-104 decibels as measured on her property, which was at an unreported distance from the commercial airboat.]
====================================================================
Search for "airboat" in http://www.aiha.org/abs01/01nois.html to find: Evaluation of Occupational Noise Exposures to Airboat Based Aquatic Herbicide Applicators by R. Maglievaz, Volusia County Health Department, DeLand, Florida. Paper 263 in Noise, Hearing Conservation and Non-ionizing Radiation of 2001 Abstracts of the American Industrial Hygiene Association (AIHE).
EXCERPT [boldface added]:
There is an industry recognition that airboats pose a noise hazard. During normal herbicide application activities, the airboat engine and propeller, not the application equipment, is the primary source of noise. Sound pressure levels increase with increasing engine and propeller RPM. Measurements indicate that the wood propeller offers an engineering control advantage over the carbon fiber propeller by shifting its energy to a portion of the noise spectrum to which the ear is less sensitive. The research found the use of aircraft engines to offer an engineering control advantage over automotive engines because they provide maximal thrust at minimal engine RPM. The dosimetry tests reveal the daily noise exposures of aquatic herbicide applicators to vary between 94 and 106 dBA. The use of earmuffs and earplugs is effective protection only when used in combination. It is therefore recommended that airboat operators and passengers wear both types of protection at all times.
====================================================================
Interior Alaska Airboat Assoc. Inc. vs. State Board of Game (3/2/01) sp-5369 in the Supreme Court of the State of Alaska. 2 March 2001.
EXCERPT [boldface added]:
"3. The [Alaska] Board of Game also heard testimony that airboat noise can range up to 135 decibels, approximately the same as the noise produced by the engine of a commercial jet aircraft being operat[ed] under full power, and that it was impossible for hunters to hear or call moose in the vicinity of such noise."
====================================================================
Marion County [Florida] Mulling Over Noise Ordinance for Airboats Associated Press in 8 October 2002 Naples Daily News (Naples, Florida newspaper).
EXCERPT: "An unmuffled airboat, frequently powered by a V-8 car engine, registers between 115 decibels and 130 decibels, according to University of Florida researchers."
====================================================================
In a 2002 article in the Salem Statesman Journal, "A University of Florida study pegged airboat noise levels at 108 decibels."
*********************************************************************
The following comments by an airboat manufacturer, American Airboat Corporation in their Airboat FAQ (1998) point out some of the sources of airboat noise.
"Most of the noise created by an airboat comes from spinning the prop over 3000 rpms. It is prop noise not engine noise.
"Noise is generally related to prop speed. One way to reduce prop noise is to reduce the spin rate or rpms that the prop turns to provide the needed thrust. This can be done several ways. ...
(1) use a reduction drive, {usually a 2:1 belt-drive reduction}
(2) install a cam that improves the engines low end performance (higher torque at lower rpms),
(3) use a propeller designed to deliver high thrust at low rpm, and
(4) use an engine designed to turn a propeller. (aircraft engine)
"The most economical solution is to install a new cam in an automotive engine. The best solution is to use a high performance automotive engine with a reduction drive in combination with a high output adjustable pitch propeller such as the PowerShift.
"The lighter weight composite props deliver more power at lower rpm and produce less
noise. This has been the key improvement in the last 5 years.
"Many airboats (and most aircraft) have no mufflers. Adding a muffler will reduce the engine noise."
====================================================================
Marion County [Florida] Mulling Over Noise Ordinance for Airboats Associated Press in 8 October 2002 Naples Daily News (Naples, Florida newspaper).
Most of airboat noise is by the propeller, so muffling the engine will not help. EXCERPT:
" 'The one big problem is that the propeller attacking the air is where the noise comes from,' said Russell Baillie, an airboat owner who lives on Lake George. 'Once you get up to cruising speed it's all the propeller, and a muffler isn't going to help that at all.' "
====================================================================
Most of the noise of a hovercraft is also from the propeller in air, as it is written in a 2003 report, Environmental Impact of Hovercraft, for Hoverdril Inc. (a hovercraft promoter):
"The major noise factor with any hovercraft is the air-propeller noise, which in any case is largely directional in characteristic..."
*********************************************************************
Paul Donheffner, Oregon State Marine Board Director, said in a 2002 Statesman Journal article that sound levels of Oregon boats are rarely enforced and that it is hard to apply a sound level rule designed for boats to airboats.
Search for "muffler" at Oregon Administrative Rule (OAR) 250-010 to find OAR 250-010-0121. This OAR is about Oregon State Marine Board noise level restrictions for engines of boats (which would be applicable to airboats and hovercraft) in Oregon waters. Note that this OAR specifically only refers to muffling the exhaust and the noise level of the engine, but that propellers make most of the airboat noise, so this OAR does not appear to limit the total noise of airboats. Randy Henry (Public Information Representative of the Oregon Marine Board) confirmed this in an email to me on 2 July 2003; he wrote: "The noise-level law pertains only to noise that the engine generates, not the propeller noise, water noise, etc."
OAR 250-010-0121 states (boldface added):
"(1) The exhaust of every internal combustion engine used on any motorboat shall be effectively muffled at all times in accordance with ORS 830.260. The term "effectively muffled" shall mean the exhaust system contains a mechanical device or appliance, designed, constructed and so used as to reduce the exhaust noise emissions of a motorboat below the maximum noise levels established in section (2) of this rule. Such device or appliance must be integral to the motorboats' exhaust system. Water muffling systems which meet this standard are those which incorporate a marine exhaust manifold.
"(2) No person shall operate a motorboat on the waters of this state that exceeds a noise level as follows:
(a) For engines manufactured before January 1, 1993, a maximum noise level of 90 dBA when subjected to a stationary test as prescribed by SAE J-2005;
(b) For engines manufactured after January 1, 1993, a maximum noise level of 88 dBA when subjected to a stationary test as prescribed by SAE J-2005.
====================================================================
Boats, including airboats, are restricted not only by noise level standards of OAR 250-010-0121 but also by other jurisdictions. For example, if boats operate in waters within a county, they would be restricted by county noise ordinances, if any.
An example of a city noise ordinance is Newport's Noise Ordinance. Lower Yaquina Bay is within the Newport City Limits (i.e., see Figure 1), and much of other Oregon estuaries may also be included within city boundaries. Accordingly, airboats operating within the city limits would be required to abide by city noise ordinances, which may be stricter than county noise ordinances.
On 9 June 2003, I contacted Peggy Hawker, the Newport City Recorder, about the Newport City Noise Ordinance. She emailed me the Ordinance the same day. Below are relevant excerpts:
"GENERAL OFFENSES
"Noise
"Section 1. No persons shall cause, allow, permit or suffer to be made any noise that unreasonably causes inconvenience, annoyance or alarm to others.
"Section 2. The following acts, although not an exclusive
enumeration, are declared to be in violation of this ordinance:
...
"F. Exhaust systems. The operation of any steam engine,
stationary internal combustion engine, vessel, boat or motor vehicle so
as to cause any greater noise or sound than reasonably necessary for its
proper operation.
...
"I. Blowers and similar devices. The operation of any
blower, power fan, compressor, internal combustion engine, or electric
motor so as to create unreasonable noise that causes inconvenience,
annoyance or alarm to another.
====================================================================
Airboats are not specifically mentioned in the Newport City Ordinance and specific measurable standards (e.g., a maximum of 90 decibels measured 5 ft away from the noise source) are not given. Section 2F would seem to allow airboat exhaust noise because that would be "reasonably necessary for its proper operation," although it is unclear if an airboat without any muffler would qualify. However, most of the noise from an airboat comes from the propeller (see Sources of Airboat Noise), not the exhaust, so airboat noise may violate section 2I.
In any case, it seems open to interpretation whether airboat noise would violate the Newport Noise Ordinance, and it is unclear if this ordinance would be enforceable against a commercial airboat, even though such noise "causes inconvenience, annoyance or alarm to others."
The noise ordinances of other Oregon cities or counties may be similar to that of Newport.
====================================================================
Figure 1. Portion of lower Yaquina Bay within the Newport City Limits.
On 9 June 2003, I visited the Newport Planning Department and talked to James
Bassingthwaite, the Director. He indicated that all of Yaquina Bay from the
mouth of the jetties upstream to a point just east of Idaho Point and east of River Mile 3 are within the Newport City Limits. He photocopied a map showing the Newport City Limits for me, but some of the lines in the map were faint and did not copy well. In making the image shown here, I photoreduced and scanned his copy, so even more details were lost. However, the City Limit boundary is still apparent, although part of the tips of the jetties is not shown. I have added labels for Newport City Limits, Idaho Flat, Sallys Bend, and King Slough.
It is clear that the South Beach Marina, Idaho Flats, the west part of Sallys Bend, and other aquatic areas of lower Yaquina Bay are within the Newport City Limits.
*********************************************************************
Near marinas or docks there are often "No Wake" or 5 mph restrictions. For example, search for "0025" in Oregon Administrative Rule (OAR) 250-010 to find OAR 250-010-0025, which states:
Basic Rule for "Slow-No Wake"
(1) No person shall operate a boat on the waters of this state in excess of a "Slow-No Wake", maximum 5 MPH speed within 200 feet of a boat launch ramp, marina with a capacity for six or more moored vessels, floating home/boathouse moorage with six or more contiguous structures, and locations where persons are working at water level on floats, logs or waterway construction.
(2) Section (1) of this rule does not apply to commercial vessels or vessels engaged in navigation on rivers where a speed in excess of 5 MPH is needed to ensure safe passage.
====================================================================
This OAR may not apply to a commercial airboat if it needs to go faster than 5 mph for safety reasons because section 2 of the OAR then negates section 1. Airboats do not have a rudder, and, in Oregon bays, it is often windy, so it is possible (though I do not know for sure) that a commercial airboat would have to be travelling faster than 5 mph to be controllable during windy conditions. For example, Jefferson Parish, Louisiana passed an ordinance limiting airboat noise; a summary of the newspaper article describing the ordinance states:
A new ordinance limiting airboat noise in Jefferson Parish, Louisiana, has been passed by the Parish Council. The restriction prohibits airboat operations within half a mile of residential areas between sunset and sunrise, and restricts airboat speeds to 5 mph during the day. Residents were pleased with the rules.
However, Airboat Swamp Tours owner Tommy Vanacor said he will not honor the
regulation. "I will continue operating my tours, but I cannot promise that I'll
idle down to 5 mph for safety reasons." Vanacor said the unique, rudderless
design of airboats necessitates higher speeds in windy conditions to keep the
boat steady. While councilman Lloyd Giardina argued that Florida had similar
restrictions on speed, Vanacor's attorney Steve Grefer said the regulations
would not stand up in court. Vanacor promises a court battle if he is given a
citation.
SOURCE: Search for "Jefferson" at http://www.nonoise.org/news/1997/apr20.htm to find: Jefferson Parish Council Passes Airboat Noise Regulation by Manuel Roig-Franzia in P. B3 of 24 April 1997 of The Times-Picayune (Jefferson Parish, Louisiana newspaper).
Local governments may try to put similar 5 mph restrictions on commercial airboats, but it is unclear if a commercial airboat during windy days in Oregon bays may need to go faster.
*********************************************************************
Search for "chasing" at Oregon Revised Statute (ORS) 498 (2001 Edition) to find ORS 498.006, which applies to airboat operators, although airboats are not specifically mentioned. ORS 498.006 states:
"Chasing or harassing wildlife prohibited. Except as the
State Fish and Wildlife Commission by rule may provide otherwise, no
person shall chase, harass, molest, worry or disturb any wildlife
except while engaged in lawfully angling for, hunting or trapping such
wildlife. [1973 c.723 §74]"
Personal watercraft, like airboats, can go into shallow waters, and personal watercraft can disturb wildlife. Accordingly, the disturbance of wildlife by personal watercraft has been specifically prohibited; search for "chase" in Oregon Administrative Rule (OAR) 250-021 to find OAR 250-021-0030, which states, in part:
"(15) No person shall chase, harass, molest, worry or disturb any
wildlife with a personal watercraft except while engaged in lawfully
angling for, hunting or trapping such wildlife (ORS 498.006)."
*********************************************************************
Lincoln City Turns Down Airboat Plan for Siletz Bay by Terry Dillman on p. A1 and A4 of 13 June 2003 Newport News-Times (Newport, Oregon, newspaper).
SUMMARY. The owner of Hut Harbor Airboats, George Hutmacher is quoted as saying about airboats: "They are noisy - they sound like an airplane" and that the best time for his airboat rides "would be on weekends during spring, summer, and fall."
Richard Townsend, Lincoln City's Planning and Community Development Director, said:
"In several areas where airboats are in use, there has been strong concern about the amount of noise they produce and their potential for disturbing wildlife."
City Manager David Hawker opposed the proposal. He said:
"I have been strongly in favor of the city trying to capitalize on the immediate environment of Siletz Bay and surrounding area. It can be a focus for a significant eco-tourist attraction. I believe its value would be seriously reduced with the presence of airboats. ... The airboats would disrupt both the wildlife and non-motorized uses. The viewing of birds from these vehicles will be restricted to their backs only as they flee the bay."
The Lincoln City Council unanimously rejected Hutmacher's request to provide airboat rides in Siletz Bay and base his airboats at Siletz Bay Park.
*********************************************************************
Airboats or hovercraft have no current restrictions in Yaquina Bay according to the Oregon State Marine Board (also search for "Lincoln" in Oregon Administrative Rule 250-020) to find rules for Lincoln County. Personal watercraft (jet skis), however, are prohibited upstream of the Toledo Airport at about River Mile 9.5 (search for "Yaquina" in Oregon Administrative Rule 250-021).
In 2003, George Hutmacher's Hut Harbor Airboats in Salem requested moorage for charter airboat rides in a letter to the Port of Newport in Yaquina Bay that was discussed at the Port Commission's April 29 Meeting. Hutmacher wrote that an airboat can "run over grass, mud, gravel, and little or no water." The Commission decided to continue talks with Hutmacher.
[Source: Airboat Tours Proposed for Yaquina Bay by Joel Gallob on p. A4 of 2 May 2003 Newport News-Times (Newport, Oregon, newspaper).]
In late May 2003, the Port of Newport Commissioners interviewed Hutmacher about his proposal to offer rides on a nine-person, 20 feet long by 8 feet wide airboat.
Commissioner Bob Jacobson raised a concern about boat congestion, and Port Manager Don Mann said he would contact the Oregon Department of Fish and Wildlife Department (ODFW) to find out if they have concerns about allowing a commercial airboat in shallow bay areas.
The Commissioners gave Mann permission for further talks with Hutmacher, and
Mann said he would contact the ODFW and other state agencies that might have
an interest in this project.
[Source: Port of Newport Interviews Airboat Ride Entrepreneur
by Joel Gallob on p. A4 of 4 June 2003 Newport News-Times (Newport, Oregon, newspaper).]
Transcript of 20 June 2003 Letter by the Oregon Department of Fish and Wildlife (ODFW) to the Port of Newport. An excerpt:
"In conclusion, ODFW opposes the operation of an airboat charter service in the bay, due to the potential for disturbance of fish and wildlife, habitat degradation, and conflict with other recreational users of the natural resources of Yaquina Bay."
Transcript of my 20 June 2003 letter to the Port of Newport about the Port's consideration of giving moorage to commercial airboats.
On 24 June 2003, the Port Commission met (Port OKs Contract for Recreational Vehicle Master Plan by Steve Card on p.A4 of 25 June 2003 Newport News-Times [Newport, Oregon, newspaper]). Port Manager Don Mann said in his report to the Commission:
"It is my opinion that the airboat would be very loud and disruptive if located in our marina, and we would no doubt receive a lot of complaints. I feel we would be better serving the public if we denied Mr. Hutmacher's request to locate in either of our marinas."
The Port of Newport's letter of June 24 to Mr. Hutmacher rejecting his request for moorage by Hut Harbor Airboats as an image or more legibly as a transcript.
Excerpt:
"... The Commission received several comments and written statements from both the general public and state and federal agencies about the adverse effects, however unintentional, that an airboat would have on migratory birds, fish, and mammals in the bay and estuary. The Commissioners also felt that airboat rides would contribute to water traffic congestion, add unwanted noise, and create certain safety risks to small recreational boats using the bay."
In my opinion, private marinas along the Newport Bayfront will probably not give moorage to charter airboats because the noisiness of the airboats would upset other patrons of the marina as well as nearby residents.
*********************************************************************
Airboats and hovercraft have been restricted from some areas in Oregon because of concerns about their effects on wildlife and emergent vegetation.
Search for "ODFW" at Marine Board To Meet Feb. 17 (Oregon State Marine Board 4 February 2000 News Release) to find:
[Item] "5. Request for Rulemaking - Fern Ridge Reservoir: US Army Corps of Engineers and the Oregon Department of Fish and Wildlife (ODFW) are requesting that motorized water craft, except those using small electric motors, be prohibited on any portion of Fern Ridge Lake south of Hwy. 126. The request would also prohibit use of airboats and hovercraft within emergent vegetation zones. The goal of the request is to protect nesting waterfowl and other wildlife as well as sensitive habitats [boldface added]. This is a request to begin rulemaking - no regulations will be adopted at this meeting."
Search for "Fern" at New Boating Regulations Approved (Oregon State Marine Board 23 June 2000 News Release) to find:
"A regulation change on Fern Ridge Reservoir in Lane County will affect two unique type of watercraft by closing about 1/3 of the lake's surface area to their use. The Army Corps of Engineers and Oregon Department of Fish and Wildlife
jointly requested that air boats - boats which us an airplane-type propeller for propulsion - and non-displacement hull hover craft - craft which hover on a cushion of air - be prohibited from areas of the lake containing emergent vegetation. These marshy areas are not accessible by most other types of boats and provide habitat for waterfowl and other wildlife, especially during nesting seasons.
"The new regulation prohibits airboat and hovercraft operation on 3,195 acres of the 9,360 acre lake. Areas affected include Coyote Creek, Amazon Bay, South Marsh and the Long Tom Area."
Also search for "Lane County" in Oregon Admininistrative Rule (OAR) 250-020 to find OAR 250-020-0221, "Boat Operations on Certain Waters in Lane County" that officially state this restriction for airboats and hovercraft.
*********************************************************************
In March 2002, George Hutmacher contacted the City of Salem about operating a nine-passenger airboat concession from the Riverfront Park boat dock (p. 1, #1). According to a Statesman Journal article, his airboat in 2002 had a 454 cubic inch engine and a top speed of 35 mph.
In April and May 2002, the City received written letters of concern about the airboat concession from the Oregon Department of Fish and Wildlife (ODFW) and the captain of the Willamette Queen Sternwheeler (p. 2, #6). The Salem Audubon Society also expressed concerns about the charter airboat that were reported in the Statesman Journal article.
The Statesman Journal article reported that the Salem's Parks and Recreation Advisory Board came to the conclusion that it would be best to work with Hutmacher, in order to have some control and mitigate the effects of his charter airboat.
In 2002, the noise level of the airboat was to be tested (p. 2, #7B), but the results are not given. The airboat may have passed the Oregon law for boat noise that is written for engine noise; however, most of the noise of airboats can be from the propeller.
In June 2002, the City of Salem approved Hutmacher's airboat concession from the Riverfront Park and/or Wallace Marine Park effective May 31 through September 30 for $50 per month plus and an annual park application fee of $50 (p. 1, #2B). Hutmacher did not get final approval for his Operator's License from the U. S. Coast Guard, so he did not offer rides in 2002 (p. 2, #9).
In 2003, Hutmacher requested to renew his Riverfront Park Use License Agreement for May 31 through September (p. 3, #1). His request was approved (p. 1, Recommendation).
In 2003, Hutmacher is to pay the City a minimum license fee of $50 per month or pro rata portion for a portion of the month that the license is used plus an annual park application permit fee of $50 (p. 5, II-A). If gross revenues exceed $30,000 per month of operation, then the license fee shall be 1% of the gross revenues for that month (p. 5, II-A).
In late May 2003, Hutmacher told the Port of Newport that he "already offers rides on the Willamette River" and that his boat passes a "blue heron rookery," with Bald Eagle nests on both sides and that "The boat doesn't bother them" (Gallob 2003b). I do not know if it has been independently confirmed that herons and eagles are not disturbed by his airboat.
Restrictions on Hutmacher's airboat operation at Salem include:
*********************************************************************
By 4 June 2003, Hutmacher's Hut Harbor Airboats had also approached the City of Coos Bay, the City of Florence, and the Port of Siuslaw along the Oregon Coast for moorage (Gallob 2003b).
Similarly, other local governments could choose to not give moorage, could have noise ordinances that restrict or exclude charter airboats, impose restrictions like the City of Salem, or include restrictions as in other areas (see next section).
*********************************************************************
Interior Alaska Airboat Assoc. Inc. vs. State Board of Game (3/2/01) sp-5369 in the Supreme Court of the State of Alaska. 2 March 2001.
The Alaska Board of Game closed the Nenana Controlled Use Area (CUA) to airboats for hunting moose "to forestall habitat alteration and eliminate conflicts between moose hunters who use airboats and moose hunters who use other means of transportation." Part of the lawsuit was also about the Noatak Controlled Unit Area where the Alaska Board of Game closed a corridor to the use of aircraft for hunting during part of the hunting season.
The court's findings of fact and conclusions of law particularly relevant to this appeal for the Nenana Controlled Use Area [boldface added]:
"1. The Board of Game heard testimony from members of the public in an area of the Tanana Flats near Nenana, Alaska, [of] airboat use by moose hunters interfering with traditional spot and stalk and stillhunting techniques used by subsistence moose hunters.
"2. The Board of Game also heard testimony that in the same area, where heavy airboat use had occurred, some wildlife habitat changes, including alterations of drainage patterns, had been observed.
"3. The Board of Game also heard testimony that airboat noise can range up to 135 decibels, approximately the same as the noise produced by the engine of a commercial jet aircraft being operat[ed] under full power, and that it was impossible for hunters to hear or call moose in the vicinity of such noise.
"4. The Board of Game also heard from airboat users and manufacturers, who testified that technological advances were addressing the noise problem, and who countered the habitat damage testimony and various other complaints raised by others about airboat use.
"5. The Board of Game concluded that a conflict existed between moose hunters using airboats and moose hunters using the more traditional spot and stalk and stillhunting methods, and that this conflict detrimentally affected the subsistence use of moose from the area, although game levels remain stable.
From Footnote 24 of the decision:
The Alaska Board of Game "... noted that 'large areas near Fairbanks remain open to airboat use for moose hunting.' Further, the Board stated that 'an area of comparable habitat, size and accessibility remains available to airboat hunters in adjacent areas of GMU 20A and GMU 20C. This adjacent area has traditionally been less important for subsistence hunters and more frequently used by airboat hunters than has the NCUA [Nenana Controlled Unit Area]."
Although moose hunters could still use airboats in some areas, the airboat association wanted access to all areas.
The Supreme Court entered final judgment dismissing the complaint of the Interior Alaska Airboat Association. Inc., so the Alaska Board of Game could exclude airboats used for hunting during the hunting season from some areas.
====================================================================
Search for "Airboat Operation" in 17. Outdoor Recreation in U.S. Army. Integrated Natural Resource Management Plan, 1998-2003, for Fort Wainwright, Alaska. The whole report is at http://www.usarak.army.mil/conservation/fw_inrmp_old.htm.
The following is from p. 152 of Chapter 17; the Army classed airboats as ORV's [boldface added]:
"Airboat operation in TFTA [Tanana Flats Training Area] is controversial. In 1988, the Army, concerned over damage by airboats in TFTA, restricted airboats to main river and stream channels in 6th Infantry Division Regulation 420-6, Management of Hunting, Trapping, and Fishing on Army Lands in Alaska. The Interior Alaska Airboat Association retained counsel, and requested reconsideration of restrictions, based on discrimination against airboat operators [footnote 21]. The Commander, after additional involvement on the part of individuals within the Airboat Association and the Alaska Congressional Delegation, rescinded restrictions on airboats, pending review of environmental considerations and recreational use."A study on environmental impacts of airboats on TFTA was conducted by CRREL (Racine, et al., 1990). Airboats were found to damage floating vegetation and affect trumpeter swan distribution. The study recommended the development of an Off-Road-Vehicle Management Plan for Tanana Flats. This study has not been done.
"A 1991 memorandum [footnote 22] summarized the issue. This action memorandum recommended: limiting airboats to the primary use area established before 1985, preparing an environmental assessment on the use of ORVs on Tanana Flats, making a decision on the use of airboats on TFTA, preparing an ORV Management Plan if airboats are allowed, and enforcing the decision.
"Initial studies in 1989, showed that airboats increase water flow in Tanana Flats by opening waterways, but that this was probably not significant. Beaver damming activity helps offset this increased water flow (Racine, et al., 1990). Since then, airboat traffic has increased, and the significance of airboats opening waterways may have increased as well. Airboats damage or destroy beaver dams. There also is concern about effects of airboat traffic on waterfowl distribution.
"ADF&G [Alaska Department of Fish and Game] is concerned about airboats, including effects on wetland hydrology and game harvest by hunters. In 1996, the area west of Wood River was closed to airboats by ADF&G. This action will increase the demand by airboat users for use of TFTA."
====================================================================
What is a Motorized Personal Watercraft? Monterey Bay National Marine Sanctuary.
Motorized Personal Watercraft in this National Marine Sanctuary includes airboats and hovercraft, and this document states [boldface added]:
"... To help protect Sanctuary habitats and sensitive marine life, it is unlawful for any person to operate motorized personal watercraft except within four designated zones and access routes within the Sanctuary. ..."Watch Out For Wildlife ... Although it may be tempting to approach them [wildlife] for a closer look, please watch them from a distance. Avoid harassment (which is illegal) by staying at least 50 to 100 yards away. Harassment includes causing an animal to change its behavior. If you want to observe wildlife while riding, idle your speed to reduce wake and noise, and watch quietly from a non-threatening distance. Disturbing animals deprives them of needed rest, may interrupt or stop feeding, or force them to burn precious energy by fleeing. These impacts can weaken animals and lead to death by stress, starvation or disease."
====================================================================
Search for "airboat" twice in Watercraft Regulations of Lake Winnebago, Missouri for excerpt:
"14. Airboats Prohibited: No Airboat shall be operated at any time on the Lake."
====================================================================
Search for "Jefferson" at http://www.nonoise.org/news/1997/apr20.htm to find: Jefferson Parish Council Passes Airboat Noise Regulation by Manuel Roig-Franzia in P. B3 of 24 April 1997 of The Times-Picayune (Jefferson Parish, Louisiana newspaper).
SUMMARY. A new ordinance limiting airboat noise in Jefferson Parish, Louisiana, has been passed by the Parish Council. The restriction prohibits airboat operations within half a mile of residential areas between sunset and sunrise, and restricts airboat speeds to 5 mph during the day. Residents were pleased with the rules. However, Airboat Swamp Tours owner Tommy Vanacor said he will not honor the regulation. "I will continue operating my tours, but I cannot promise that I'll idle down to 5 mph for safety reasons." Vanacor said the unique, rudderless design of airboats necessitates higher speeds in windy conditions to keep the boat steady. While councilman Lloyd Giardina argued that Florida had similar restrictions on speed, Vanacor's attorney Steve Grefer said the regulations would not stand up in court. Vanacor promises a court battle if he is given a citation.
====================================================================
"At least seven counties and three cities in Florida have some airboat regulations, she noted, and they deal with hours of operation, permitted areas of use, mufflers, sound levels, public safety, propeller blast, lights, launching hours and speed limits."
These restrictions were probably at least in part a response to the National Park Service's 1999 Environmental Assessment for this Preserve. Brian Scherf, Florida Biodiversity Project, requested people to comment on this Environmental Assessment in his 1999 alert that also discusses problems with airboats: Commercial Airboat Operations Damaging Big Cypress National Preserve.
*********************************************************************
Reading the testimony at meetings or hearings is a good way to grasp the controversy that has arisen about unrestricted airboat usage in some areas.
It would be wise to learn from the experience of others rather than waiting for the problems that have arisen elsewhere to be repeated in one's own location. After a problem has arisen, it is considerably more difficult to deal with than if it can be "nipped in the bud."
====================================================================
Search for "Participants" in Shiawassee National Wildlife Refuge Draft Comprehensive Conservation Plan Summary [U.S. Fish and Wildlife Service Shiawassee National Wildlife Refuge, 6975 Mower Road, Saginaw, Michigan 48601]. Part of this states [boldface added]:
"Participants in open house events and focus group meetings expressed a wide range of philosophies on public use of the Refuge. ... The subject of airboats on rivers flowing through the Refuge drew a strong response from people who believe that the Refuge should provide a tranquil place to view birds. Airboat operators were described as having 'disregard' for anglers and wildlife observers. Comments included concerns about safety on the river as well as the noise disturbance. Participants suggested a variety of solutions, including instituting a no-wake zone; expanding noise abatement codes; strictly enforcing wildlife harassment codes; and implementing horsepower or speed restrictions."
====================================================================
Search for "Airboat" in Minutes: State of North Carolina Board of Commissioners, County of Henderson (19 May 1999) for the start of the Commissioner's discussion and later Public Input.
An airboat guide (Mike Levins) spoke in favor of airboats. Other speakers presented their concerns that were mostly about a commercial airboat, which was larger and noisier than Levins' airboat. Concerns included airboat noise, airboat wakes, airboat speed, human safety for other boaters (especially kayakers and canoers), and disturbance of wildlife.
Link to Margaret Gibbs' comments about noise.
====================================================================
Search for "Restricting" in Council Minutes: Fort Myers Beach (Florida) Town Council Meeting (22 February 1999) to read about the Public Hearing about banning airboats.
Portions of the Minutes about Ilene Barnett's comments [boldface added]:
"Ms. Barnett said [she] has worked for the county and the state (DEP) and has worked at Big Cypress and Everglades. The Marine Resources Task Force was appointed by the Town Council to deal with environmental issues. The area outside of the town’s jurisdiction still has concern to them. The MRTF hasn’t yet had a chance to work on a back bay management plan, but they will in the near future. They will be addressing the appropriate usage of all kinds of vessels, but the airboat issue is timely now. They do not have a lot of activity now and we can save a lot of heartache in the future if we address it now. The main environmental impact is the airboats are much louder than most other boats. The other issue is the impact to the shallow estuary system and wetlands. Most vessels except canoes and kayaks and jet skis cannot get in these shallow areas. Jet skis can do some damage, but mostly they are used in deep water. Airboats were designed to get into the marshlands. She handed out an aerial photograph of the Big Cypress Preserve. It shows scars on very shallow freshwater marches [marshes ?] from airboats. They are having a hard time shutting them out because there are so many there who are operating commercially. She also cited a study about disturbance of nesting bird colonies by the Game and Fish commission. It compared the impacts of someone walking slowly toward a nesting colony, canoeing near a nest, using a small boat with 30 hp motor, and using a 14-foot airboat. The airboat impact was much more than any of the other three. All species were affected. The minimum setback for approaching protected wading birds should be almost 1000 feet. She cited a letter from Nancy Douglas, a biologist with the Freshwater Game Commission that said that most sensitive species react at 200 meters. In Estero Bay it would be difficult to operate airboats without disturbing. There are two national wildlife refuges that have already banned airboats. She read a report that the extreme noise generated by the airboats disturbs the nesting eagles even when they are outside the preserve boundaries. The other impact is from shallow areas. She read a letter from an expert on mangroves who said that airboats form a large wake and that causes erosion and changes the sediment patterns which mangroves are very sensitive to. She read another letter that said the pressure of the airboat hulls causes compaction of fragile soils. ..."
Other speakers discussed concerns about excessive noise of airboats, human safety concerns about near-collisions of boats with airboats, disturbance of wildlife, and impact on habitat.
The City Council voted unanimously to ban airboats from their "Back Bay."
====================================================================
Search for "Airboat" in Minutes of the Meeting of the Board of County Commissioners, Brevard County, Florida (19 May 1998) and read the whole section for discussion by airboat proponents or citizens complaining about airboat noise, inappropriate speed, danger to small boats, erosion, and wildlife disturbance. Most of the complaints and concerns seems to be concentrated on one commercial airboat.
====================================================================
Airboat Noise Rattles Homeowners by Jeffrey S. Solochek in 27 January 2002 St. Petersburg Times (St. Petersburg, Florida newspaper).
SUMMARY. Residents brought complaints about airboats to county commissioners. An airboat user said that a few airboaters were the source of the problems.
*********************************************************************
Airboats can affect wildlife because of their:
1) noise
2) intrusion into areas that are otherwise not disturbed by boats or humans
Search for "Air boat" [airboat is sometimes spelled as 2 words] at What is a Motorized Personal Watercraft? by Monterey Bay National Marine Sanctuary. An excerpt states that personal watercraft, which includes airboats and hovercraft, should:
"Avoid harassment (which is illegal) by staying at least 50 to 100 yards away. Harassment includes causing an animal to change its behavior. ... Disturbing animals deprives them of needed rest, may interrupt or stop feeding, or force them to burn precious energy by fleeing. These impacts can weaken animals and lead to death by stress, starvation or disease."
To reduce disturbance of nesting or foraging birds, buffer zones have sometimes been recommended (see references below and in the next section). But buffer zones would be hard to enforce for Bald Eagles and other wildlife because airboat or hovercraft operators may not see the wildlife until after the wildlife are disturbed or not realize that they are within the buffer zone for wildlife. Accordingly, regulations that prohibit airboats from specific areas where wildlife are regularly present would probably be more enforceable and also reduce wildlife disturbance. For example, airboats and hovercraft have been prohibited from specific portions of Fern Ridge Reservoir in Oregon.
Bartelt, G. A. 1987. Effects of disturbance and hunting on the behavior of Canada Goose family groups in eastcentral Wisconsin. Journal of Wildlife Management 51:517-522.
Airboats were observed to unintentionally disturb Canada Geese and were also used intentionally to disturb Canada Geese families for experimental purposes.
Search for "Airboat" in Erwin, K. L. 1999. Southwest Florida International Airport: Border Collie Effectiveness as a Method
of Wildlife Control. Lee County Port Authority, Florida.
The ability of airboats to disturb birds was recognized and was being considered as a management tool to keep birds away from an airport. EXCERPT: "An airboat would be very effective in flushing wading birds, shore birds, blackbirds, and waterfowl out of the east-west drainage swale and out of the AOA [Air Operations Area]."
Jahn, L. R. and R. A. Hunt. 1964. Duck and coot ecology and management in Wisconsin. Michigan Dept. of Natural Resources Technical Bulletin 73.
The abstract of this article by York (1994:10-11), states: "Airboats easily invade shallow-water areas of most value to waterfowl and pose a serious threat to waterfowl production in Wisconsin."
Linscombe, J. T., T. J. Hess, Jr.; and V. L. Wright. 1999. Effects of seismic operations on Louisiana's nesting Bald Eagles. Proceedings Annual Conference Southeastern Association Fish and Wildlife Agencies 53:235-242. (This is at SK1.S6 at OSU Libraries.)
In 1998 tests, eagles began flushing when an airboat approached within 310 m (1,017 ft) of their nest, and, in 1999, eagles began flushing when an airboat was 460 m (1,509 ft) away. The authors recommended reducing the 460 m buffer zone recommended by the U.S. Fish and Wildlife Service and Louisiana Department of Wildlife and Fisheries to 310 m, but their data suggest that 460 m is appropriate for airboats as that is when flushing began in 1999.
Mabie, D. W., L. A. Johnson, B. C. Thompson, J. C. Barron, and R. B. Taylor. 1989. Responses of wintering Whooping Cranes to airboat and hunting activities on the Texas Coast. Wildlife Society Bulletin 17:249-253.
From their Table 2, crane families flushed when an airboat was an average of 177 m (581 ft) away, but the distance when flushed ranged from 25-275 m (82-902 ft).
On their p. 252, they write: "Airboats directly approaching cranes clearly caused responses that may be tolerable when occurring occasionally, but may cause altered use of territories if repeated frequently."
Rusch et al. 1985. Evaluation of efforts to redistribute Canada geese. Transactions North American Wildlife and Natural Resources Conference 50:506-524.
Based on an abstract in Dahlgren and Korschgen (1992:45), the ability of airboats to disturb wildlife was so well-known that airboats were used intentionally as a management tool to haze Canada geese at Horicon National Wildlife Refuge.
*********************************************************************
The following references in scientific journals that are not available on the Internet are not specifically for airboats, but airboats would be expected to have similar disturbance effects, although Ilene Barnett reported that a 14 ft airboat disturbed birds more than a boat with a 30-hp engine. Airboats can also go into areas where boats cannot, so wildlife disturbance by airboats would be over a greater area than boats that are confined to channels that may allow wildlife habituation.
There are many more articles than can all be listed here; for example, see reviews by Dahlgren and Korschgen (1992:54) and York (1994:29).
Bratton, S. P. 1990. Boat disturbance of Ciconiiformes in Georgia estuaries. Colonial Waterbirds 13(2):124-128.
Using 15 and 21 ft boats travelling at an average of about 9 mph, Bratton found that foraging wading birds began to be flushed when a boat approached to within about 55 m (180 ft) of the birds. The flushing distance for boats traveling faster may differ.
Dahlgren, R. B. and C. E. Korschgen. 1992. Human disturbances of waterfowl: an annotated bibliography. U.S. Fish and Wildlife Service, Resource Publication 188. (This is at SK361.A553 in OSU Libraries.)
On p. 2, they tallied a total of 66 papers about boat disturbance of waterfowl that are included in their bibliography; the annotated references are listed on their p. 54.
McGarigal, K. 1988. Human-eagle interactions on the lower Columbia River. Master of Science Thesis, Oregon State University. Corvallis, Oregon.
This research was conducted downstream of Longview, Washington in the Columbia River. On p. 104, it is written that buffer zones of 200 m (656 ft) and 350 m (1,148 ft) would be required to protect 50% and 95% of foraging Bald Eagles from being flushed by moving boats. The size, speed, and noise level of the boats was not reported.
On p. 106, he wrote: "I recommend buffer zones 400 m (1,312 ft) wide around high-use foraging areas as the single most appropriate and practical management strategy."
McGarigal, K., R. G. Anthony, and F. B. Isaacs. 1991. Interactions of humans and Bald Eagles on the Columbia River Estuary. Wildlife Monographs No. 115. (Results are probably mostly from McGarigal 1988.)
Rodgers, J. A. and S. T. Schwikert. 2002. Buffer-zone distances to protect foraging and loafing waterbirds from disturbance by personal watercraft and outboard-powered boats. Conservation Biology 16(1):216-224.
From their abstract: "Our data suggest that a single buffer-zone distance can be developed for both PWC [personal watercraft] and outboard-powered vessels. Buffer zones of 180 m [591 ft] for wading birds, 140 m [459 ft] for terns and gulls, 100 m [328 ft] for plovers and sandpipers, and 150 m [492 ft] for ospreys would minimize their disturbance at foraging and loafing sites in Florida."
The following tabulation is from their Table 2 on their p. 222 and gives the minimum recommended buffer-zone distances between waterbirds and the approach of personal watercraft or a 30-horse power outboard boat moving directly towards waterbirds at 35-40 km/hour (22-25 mph) to prevent flushing. Only species occurring along the Oregon coast are listed below, and distances in feet have also been calculated and added. The flushing distance may differ at other speeds or for airboats. -=no data given.
---------------------------------------------------------
Distance to Prevent Flushing
Personal Outboard
Watercraft Boat________
Species (m) (ft) (m) (ft)
------------------------------------------------------
Brown Pelican 183 600 147 482
Double-crested Cormorant 156 512 132 433
Great Blue Heron 145 476 133 436
Great Egret 130 427 146 479
Caspian Tern 98 322 - -
Black-bellied Plover 88 289 84 276
Willet 91 299 94 308
Short-billed Dowitcher 82 269 - -
Osprey 142 466 149 489
---------------------------------------------------------
Rodgers, J. A. and H. T. Smith. 1995. Set-back distances to protect nesting bird colonies from human disturbance in Florida. Conservation Biology 9(1):89-99.
They calculated buffer zones for nesting waterbirds and discussed results of other researchers. For the only species that nests along the Oregon Coast, Great Blue Heron, they recommended a buffer zone of 82 m (269 ft) for a 14 ft boat with a 30 hp outboard motor travelling at 1 mph at a noise level of 80-85 dBa.
My comment: the setback may need to be greater for an airboat traveling faster.
Stalmaster, M. V. and J. L. Kaiser. 1997. Flushing responses of wintering Bald Eagles to military activity. Journal of Wildlife Management 61(4):1307-1313.
They studied flushing responses of wintering bald eagles to military firing activity, helicopter overflights, and boating on the Nisqually River and Muck Creek on the Fort Lewis Army Reservation, Washington, during 1991-94. Sixty-one percent of 1,825 eagles flushed in response to 52 experimental boat disturbances on the Nisqually River. Subadults flushed more often than adults, and eagles feeding or standing on the ground flushed more often than those perching in trees. Their data suggest that ordnance explosions, low-level helicopter overflights, and boating should be restricted near eagle foraging areas.
Stalmaster, M. V. and J. L. Kaiser. 1998. Effects of recreational activity on wintering Bald Eagles. Wildlife Monographs No. 137:1-46.
The effect of recreational activities on wintering bald eagles along the
Skagit River Bald Eagle Natural Area in northwest Washington was studied. Boats coming by early in the morning were most disturbing. Eagles that were feeding were less
tolerant of humans than eagles that were perching. With increasing numbers
of disturbances, eagles took increasingly longer to resume feeding.
Suryan, R. M. and J. T. Harvey. 1999. Variability in reactions of Pacific harbor seals, Phoca vitulina richardsi, to disturbance. Fishery Bulletin 97(2):332-339.
The authors observed disturbances to harbor seals and the seals' responses to
the disturbances during 1991 and 1992 at three sites in Washington State. Harassment of seals on shore was common and caused mainly by operators of powerboats coming close to observe the seals.
Vos, D. K., R. A. Ryder, and W. D. Graul. 1985. Response of breeding Great Blue Herons to human disturbance in northcentral Colorado. Colonial Waterbirds 8(1):13-22.
For a 12 ft boat with a 9.5 hp outboard engine traveling at 7-10 mph, they recommended a buffer zone of 150 m (492 ft).
My comment: the buffer zone may need to be greater for an airboat traveling faster.
York, D. 1994. Recreational-boating disturbances of natural communities and wildlife: an annotated bibliography. U. S. Dept. Interior, National Biological Survey, Biological Report 22. (This is QH301.U4 No. 22 at OSU Libraries.)
On p. 29-30, different subjects are indexed, including disturbances affecting Habitat, Watercraft Disturbances, Disturbance Effects, and Management Techniques.
*********************************************************************
It appears that there are few reports about the negative impacts of airboats on habitat that are widely available. However, the lack of published reports does not mean that airboats have no impacts. Reports may largely be in unpublished governmental reports.
Racine, C. H., J. C. Walters, and M. T. Jorgenson. 1998. Airboat Use and Disturbance of Floating Mat Fen Wetlands in Interior Alaska, U.S.A. Arctic 51(4):371-377.
The following is from their Abstract [boldface added]:
"The use of airboats is expanding in Alaska, particularly in the interior. This study describes the nature, magnitude, and distribution of disturbances caused by airboat trails over floating mat fen wetlands in the Tanana Flats near Fairbanks, Alaska. Airphoto interpretation showed over 300 km of airboat trails by 1995, with a 15% expansion of the trail system since 1989. Field sampling was done at 30 trail and adjacent control sites along this trail system to assess changes in hydrology, soils, and vegetation. Water velocities in the trails at two-thirds of the sites were at least an order of magnitude greater than velocities of less than 1.5 cm per sec in the control areas. On average, 30 cm of the 0.5-0.75 m thick floating mat has been removed or eroded by airboat traffic at the sampling locations. Nearly all emergent floating mat vegetation has been destroyed (5% cover remaining on average) so that the trails resemble a highly visible open water stream channel 2-3 m wide through the floating mats. Although the recovery and regrowth potential of floating mats in trails in high, recovery is unlikely in trails with continuing use.
====================================================================
Schaffranek, R. W. Analysis of Sheet Flows to Florida Bay from C-111 Canal. Abstract from the Proceedings of the South Florida Restoration Science Forum Open File Report. U. S. Geological Survey. Search fopr "Airboat" to find:
"Flow measurements were made in the center and about 150 m on both sides of an established airboat trail that traverses the wetland southward from the canal. Vegetation within this and other established airboat trails in the area is substantially compressed and presents less biomass throughout the water column than does vegetation in the surrounding undisturbed wetland."
====================================================================
Airboat Trails May Be Aiding Mosquitoes by Mark Holan on p. 1 of the Pasco section of the 7 May 2003 Tampa Tribune (Tampa, Florida newspaper. Search for "airboat" at http://archive.tampatrib.com/ [Tampa Tribune Online]. From LexisNexis Academic documents [boldface added]:
"... Airboat trails slicing through the marsh grass at Werner-Boyce Salt Springs Park are giving state parks and mosquito control officials worry lines. There are no plans to halt boating, which officials say has increased steadily over the past three years and may be hindering the battle against mosquitoes. ... Damage caused by airboats may help the pests breed, officials say. The boats can travel 55 mph as they glide over shallow areas that can't be reached by other water craft.
"Since 2000, airboats have 'dredged a vast network of shallow ditches throughout the [park's] black rush marshes,' mosquito district entomologist Doug Wassmer wrote in a report to state parks and environmental regulators. 'If isolated from tidal flushing action, the damaged areas can become rearing sites for salt marsh mosquito larvae,' he wrote. 'These areas may need to be restored, and airboats should be excluded from using these areas of the park.'
"A videotape recorded by mosquito district pilots flying over Werner-Boyce shows the damage, Wassmer said."
====================================================================
Wright, A. 2001. Not just a bunch of hot air: the ecological impacts of airboats. Road-RIPorter 6(1):6-7, 14. Published by Wildlands CPR (http://www.wildlandscpr.org/). This 192K PDF file was provided by Brian Scherf, Florida Biodiversity Project.
Note that this article cites many governmental reports in Florida that are not available to me about the harmful effects of airboats. She discusses airboat impacts that include: increases in turbidity, rutting of soils in low water conditions that could cause oxidation, and declines in mangroves and emergent sawgrasses.
An additional unpublished, governmental report in a database search for airboat at http://www.wildlandscpr.org/ is given below. Since its subject was specifically about airboats, there must have been a concern about airboats that led to this report being written.
Kenny, P. 1994. Ochopee airboat impact briefing paper. Ochopee, FL, US Department of the Interior, National Park Service, Big Cypress National Preserve.
====================================================================
The minutes of Ilene Barnett's testimony at a Fort Myers Beach Town Council meeting states: "She read a letter from an expert on mangroves who said that airboats form a large wake and that causes erosion and changes the sediment patterns which mangroves are very sensitive to. She read another letter that said the pressure of the airboat hulls causes compaction of fragile soils. ..."
Airboats have the potential to impact intertidal vegetation at Oregon estuaries. Operators of normal boats avoid estuarine eelgrass and algae either by not going into exposed beds or by waiting to high tides to float over the top of vegetation because aquatic vegetation fouls their propellers. So normal boats would be expected to have minimal impact on estuarine, aquatic vegetation.
An airboat, however, could pass through floating estuarine eelgrass and algae as the tide level drops. Then the airboat could drag and break off eelgrass or algae, similarly to the impact noticed by airboats on emergent plants elsewhere (see effects of airboats on vegetation).
When the tide drops to where eelgrass and algae lie on the mudflats, then an airboat can have a pressure impact by passing directly on the vegetation. The pressure impact may depend upon the speed of an airboat. I imagine that an airboat may travel easily over firm sandflats, but an airboat travelling below a certain speed may sink into less-firm mudflats, so that the airboat may plow through the top of the mud rather than skimming the surface. An airboat plowing through the top of the mudflats could have a significantly negative impact on intertidal vegetation and surface-dwelling mudflat invertebrates such as cockles and steamer clams.
In a 2003 report, Environmental Impact of Hovercraft, for Hoverdril Inc. (a hovercraft promoter), the impact of hovercraft is said to be generally nil and temporary because a hovercraft's air cushion protects the substrate. For example, search for "footprint" in this report to find:
"Damage to the shore environment, such as beaches, mud flats and vegetation is virtually nil because of the hovercraft's low pressure 'footprint.' For example, the average human being when standing on a beach exerts a pressure of some 3 lbs per square inch underfoot, rising locally to 25 lbs per square inch when walking. The average hovercraft by comparison, exerts a pressure of only 0.33 lb per square inch on the surface regardless of speed. This 'footprint' pressure is less than that of a seagull standing on one leg!"
However, I have observed that gulls walking on two legs leave tracks on estuarine mudflats, so it is possible that a hovercraft, depending upon the substrate, may also sometimes leave a trail, in spite of low "footprint" pressure. Indeed, I have seen a hovercraft in 2003 leave a trail on flat, barren, estuarine mudflats at low tide, although this trail may have been faint enough that it was "erased" by the next high tide. The longevity of the trail may depend upon the firmness of the substrate and how many times a hovercraft uses the same route. I have also seen in 2003 where repeated hovercraft launchings and landings devegetated a sloped, sand berm; the impact of hovercraft a may be greatest when it is travelling along a slope. Accordingly, the statement that a hovercraft can not leave trails or can never have a significant impact is not true.
Some of the effects of boats may also apply to airboats. However, boat propeller damage would not apply because airboats and hovercraft do not have propellers in the water like boats.
Airboats would have a greater impact on mudflat invertebrates or algae or seagrass communities than hovercraft because hovercraft ride above the substrate on a cushion of air.
References
Liddle, M. J. and H. R. A. Scorgie. 1980. The effects of recreation on freshwater plants and animals: a review. Biological Conservation 17:183-206.
From abstract in Dahlgren and Korschgen (1992:32): Effects of boats that may apply to airboats include direct contact of plants, wash, and turbidity. This review is 23 years old, but I have not found a more recent review.
Luttenton, M. R. and R. G. Rada. 1986. Effects of disturbance on ephiphytic community architecture. Journal of Phycology 22:320-326.
From their Abstract: "... Localized physical disturbance, induced by boat traffic and wind-generated wave action in the main channel, inhibited development of complex attached algal communities and maintained an adnate flora with two-dimensional architecture. In contrast, communities protected from disturbance developed a more complex, three-dimensional architecture. ..."
York (1994:229) is an annotated bibliography that includes effects of recreational boating on Habitat and, at the end, Miscellaneous Subjects that includes algae/phytoplankton, aquatic plant disturbance, pollution, and turbidity. In skimming his bibliography, I did not see that any of his references for these subjects would be directly applicable to airboats.
*********************************************************************
It is important to recognize that there are proponents of airboats, including airboat manufacturers, airboat tour owners, and airboat owners and their associations. In general, airboat enthusiasts believe complaints about airboat noise and disturbance have been exaggerated and that more restrictions on airboats are not needed.
Please read the 2002 Statesman Journal article that gives some of Hutmacher's viewpoints about his proposal to operate a charter airboat at Salem.
To see some of the viewpoints by airboat manufacturers:
Trail Boss Airboats.
American Airboat Corporation--Airboat FAQ
Also read through the minutes of meetings and hearings (see Public Testimony) because such testimony usually includes testimony by airboat proponents.
Finally, search the Internet (e.g., Google http://www.google.com/) for their opinions by searching for "airboats" or "airboat tours."
In my opinion, proponents are far more organized than those who wish to restrict or ban airboats from some areas because of their noise or disturbance of wildlife. For example, an airboat association in Alaska filed a lawsuit and took it on appeal to the Alaska Supreme Court.
*********************************************************************
The current issue is whether local governments will allow moorage for a charter airboat service at several Oregon bays (see Other Oregon Local Governments Have Been Approached for Moorage). They could choose to not give moorage, could have noise ordinances that restrict or exclude charter airboats, impose restrictions like the City of Salem, or include restrictions as in other areas (see Restrictions Placed on Airboats Outside of Oregon Because of Their Noise or Disturbance).
In the future, consideration of regulations for airboats could involve buffer zones around wildlife (e.g., see references in Boat Disturbances of Wildlife and York 1994:29). But buffer zones may be hard to enforce around wildlife--see Airboat Disturbance of Wildlife. It seems that it might be more enforceable to have specific area closures for sites that are often used by wildlife.
York (1994:29) has indexed "Management Techniques" for disturbances that also includes zoning changes. These references may also be informative.
There are currently no regulations specifically for airboats at Oregon estuaries. One way to adopt changes to regulate airboats is outlined in Oregon Administrative Rules 250-19: Oregon State Marine Board, Division 19. Procedures for Adopting, Amending and Repealing Local and Special Rules.
This appears to be the process that was used to exclude airboats and hovercraft from 1/3 of Fern Ridge Reservoir.
*********************************************************************
Email comments to Range Bayer, P. O. Box 1467, Newport, Oregon 97365 USA.