If Bird Brains are so Tiny, Then Why is it that We Humans Have So Much Trouble Outwitting Them? Seaworthy Readers Fight Back!
I read with interest your January article on Jonathon and believe I have a solution. After being visited and revisited by the noble birds, I was told that they won't go near netting in fear of being trapped. I framed some fishnet with rope to give it shape and draped it on the bow of my boat tying it to the headsail and lifelines. It only takes a minute to put it in place and for the past two years it has done the trick. On occasion, I find a crab in the netting, which I assume gulls drop to break them prior to dining, but they don't seem interested in retrieving them. I have enclosed a picture of my boat showing the netting in place. You can see that I have a rather large dodger-bimini on the boat, and although it is not near the netting, birds don't appear interested in using it as a dining/resting area. Hope this helps my fellow boaters.
Your January 2002 issue was most interesting, and contained many helpful articles, which I'll save for future reference.
Having seen firsthand the results of Jonathan Livingston's revenge on boaters here in Massachusetts, it prompted me to write of my own experience and a somewhat temporary but successful solution to the pesky critters. My 23' Sea Ray was also on a mooring in Scituate, MA; and with a new navy blue canvas top was for some reason a tempting target for the seagulls. This happened mostly in the early fall when a lot of other craft had been hauled, but the local fishing pier and draggers with their catch were still in action.
My idea was to purchase (at a local variety and gift store) a dozen or so shiny and colorful pinwheels on sticks that a child would play with in the wind. I removed these from the sticks; and using lead-core fishing line, strung them from bow rail to top light to transom. Appropriate knots between each "wheel" kept them spaced about 3 - 4' apart. Apparently the "pesky critters" do not like the movement and reflecting light- even on a cloudy day or with the slightest breeze!
This worked very well until hauling time and we even saw some copycats on other nearby boats.
Hope this is of interest and wish I knew how to market the idea on a practical large scale. Keep up the great work.
We have both a boat and 5th wheel trailer with the same problem. My wife came up with an idea that has worked well for us. Most birds do not like shinny moving items. We have taken Christmas garland and wrapped it around the areas where the birds sit. It has almost eliminated our problem on the boat and the trailer.
For the sailboat we raise several strands up the mast and tie them off down below. Over the boom we just wrap it.
For cleaning try a product called spray power by Crown. Their web site is www.spraypower.com. It takes off a lot of stuff and cleans streaks, etc. They sell it by the case of 32 oz bottles all the way to a 55-gallon drum.
Birds will not settle if you can put monofilament fish line above whatever you are trying to protect.
It does work on pontoon tops! Mount it about 12 inches above whatever.
Yes I have the same problem with seagulls. I have a 267T CRIST-C with a blue navy top (powerboat) at mooring "Think Chinese."
When you get Chinese food it is served in an aluminum food dish. This is what I used on my CC, about six, with a six-foot mast in the center of boat. It works.
Sailboats in my area don't seem to have this problem, only my powerboat, because of lack of a mast. Seagulls like the blue navy top in all kinds of weather.
Hope I helped.
PS I still love God's seagulls.
In response to your inquiry about keeping birds off of sailboat spreaders I am suggesting what we have used very successfully on our 1989 Pearson 31. We moor the boat in Chatham, MA, where cormorants have periodically made unbelievable messes of many boat decks and cockpits in Stage Harbor. Stage Harbor Marine came up with the idea of wrapping plastic industrial cable ties around the spreaders, tails up, as shown in the sketch below. The ties need to be about 18 inches long overall to be effective.
Having used wires and such in the past, we find this solution to be the best we have come across. The ties are inexpensive, easy to install, don't harm the sails and don't seem to suffer from exposure to the sun over several seasons.
Worse than seagulls and cormorants would be the attack of the Terns. By the hundreds, they chased bait fish in Narragansett Bay, RI and made an outhouse of my moored sailboat and many others nearby. They perched on the boom, the spreaders, shrouds, stays and of course, the bow and stern pulpits.
What worked for me on my C & C 34 was the multi-colored plastic flags often seen in used car lots. I picked up about a 50' length, tied it off on the stern rail, ran it through the mainsail halyard shackle (with a separate line tied to the shackle to keep it in line with the mast and as a back-up to retrieve the halyard) and raised it to the spreaders. The balance was led forward and tied off at the bow pulpit. While it looked like I had won the America's Cup, my boat was untouched while others continued getting bombed.
The birds did not like the rustling noise and constant movement of the flags as it disturbed their defensive mechanism of hearing and sight, which threatened their safety. It took only minutes to set up and remove and the boat stayed clean.
One more suggestion: Running a plastic grocery bag tied off to the main halyard to the top of the mast scared of a large hawk (which broke my windex) and a messy cormorant.
A solution for "Jonathan Livingston Seagull"-and for all of his "FINE FEATHERED FRIENDS"- I HOPE!
A number of years ago I purchased a "mooring" in Newport Harbor, Newport Beach, California- to purchase the mooring you must also purchase the boat assigned to the mooring. My "new" boat had been on the mooring for a number of years without attention. The poor girl had a botanical garden on the bottom and a "GUANO" factory on deck- spreaders- boom- railings- anywhere a bird could land-or a position from which it could drop its bombs. The old statement "thank God that cows can't fly" may have been in error-it took a shovel, a hammer and chipping tool to remove the deposits from the boat, a joyous task.
A friend had a large sailboat in the same area, and observing the fact that his boat was spotless with other neighbors not so fortunate, I went closer to observe. Joe had strung monofilament fishing line above his boom and over the lifelines-to the bow and stern pulpits.
That evening I called Joe regarding his system- yes he had feathered friends prior to his stringing the mono. He said that after the first stringing he had retired to a reasonable distance and watched the bird's attempt to land, running into the mono and crashing. The word must have gotten around that this was not a friendly landing area-the birds avoid his boat like "grim death," even though he has reduced the amount of mono significantly.
With my boat, I found some "nursery netting" to keep birds off plants - I have sewn a ridge line to this so I can stretch my netting from the bow pulpit, over my raised 32 degree light on the bridge and to a stanchion placed in my center rod holder on the transom- the netting "tents" from the centerline, port and no more guano on my "NEW" powerboat.
Yes, I am a "turncoat" after over 60 years of sailing I now am a "stinkpotter."
P.S. "So my former sailing friends don't come out and play games with my nice clean boat."
Ducks and other birds with wet feet have been kept off our 17 year old Hunter sailboat with the hottest hot sauce we can buy. Your final wash down should be with a brush and a bucket of water with hot sauce mixed with the water. Scrub the mixture onto docks, decks, dodgers, seats, sail covers, etc. Do not rinse. Birds land with wet feet, activate the hot sauce, and fly into the water, more wet feet, make hot sauce landings! You get the picture.
It works for us!
PS I have no feedback from the environmentalist and tree huggers, however; it doesn't seem to hurt the birds.
The photo and article in Volume 20 No. 1 strikes fear into my heart and sweat onto my brow. I have fought the cormorant problem for years. We have a twin keel sloop in a small harbor called Green Pond, just North of Falmouth harbor on Cape Cod, MA.
The cormorants love to sit on top of QUIET pilings or on sailboat spreaders, which swing QUIETLY on moorings, away from docks. They swim and dive underwater, eating eels and other tidbits. Where Great White Sharks may be called EATING machines, CORMORANTS can only be considered POOPING machines. They can propel their droppings quite far, like a small cannon.
In the 1990's the problem became monstrous. My mooring neighbors threatened to shoot them off their spreaders. Of course they probably would have missed and only caused more damage. My red canvas must have seemed uninviting to the Beasts or maybe the bird wire stretched between the upper shrouds, just above the spreader was in fact working. That didn't last long-UGH. Hours of cleanup prior to taking a day sail.
Phase 1 consisted of the usual streamers and whirligigs attached to stays and halyards, which were pulled aloft. Without wind, these don't work. Phase 2 required more thought. Why not crisscross the halyards and every damn line available across the landing zone. They usually fly over the stern and land on the spreaders, where they dry their wings after their lengthy underwater feedings. This seemed to work for a week or so. Then after a beautiful day on the water and lunch at Vineyard Haven, we returned to the mooring and prepared for cocktail hour. While sipping a perfectly prepared vodka tonic and chatting with my wife and her mom, who crewed for us that day, a DAMN juvenile CORMORANT flew over us. The beast flew into my crisscross, and then made it to the spreaders. He/she had no manners and wasn't properly dressed. After finally whacking him with a loose line, he leapt onto the furled genoa: about 2/3 of the way up. My thought to shoot the beast was tempered with the knowledge that if I missed and hit the sail, foil or head stay, well you know-$$$. I shook the head stay, till I thought it might let go. The DAMN thing held on like glue. Finally the BEAST gave in and swooped to a neighbor's boat. That boat only had one cormorant on the port side. My intruder went to starboard. The mast must act as a bundling board for them. During this confrontation I noted something unusual. What was glistening on the spreaders and masthead of a Pearson, which was owned by a relative of my wife's children? We took a spin around his boat and I observed wire strands sticking out of his spreaders. They bowed aft a bit and seemed 4 inches tall. Looked like several hundred little wires. There was also a group of them at the top of the mast. Well it suddenly dawned on me that I had never heard him curse the BEASTS, nor seen him cleaning up their droppings. A MIRACLE.
After speaking to Mike about his ingenious CORMORANT PREVENTER, I formulated my plan of attack. Thankfully, sailing and cleaning season was almost over. After the boat was hauled, mast stepped and tucked away, I brought home the spreaders and masthead. The masthead had to be protected also, as the BEASTS love to sit on top and snuggle in between the antenna and windex. I discovered that one night after coming back from a dinner with friends. While having a smoke on their back deck, which overlooks the harbor, I saw a dark object on top of the mast. I rubbed my eyes and waiting for Gerry to get his multi-million candle power lantern. We shone the light on the object and a DAMN CORMORANT was perched atop. I guess the lantern must have disturbed its siesta. Off it went-PHEW. I realized then why my antenna was bent backward a bit and why I had lost a new windex a week earlier. I blamed the boatyard for not tightening it properly. OOPS.
Phase three consisted of finding the right ingredients and attaching them to the spreaders and masthead. Mike's wires were apparently now unobtainable and even though he had never had problems, their proximity to a tacking headsail worried me. Lo and behold, I found an ad for Bird-B-Gone in a publication. Those nice folks sent me a brochure. The plastic spikes looked pretty POTENT. Only one problem: I had to buy enough to do several boats. Oh well, I'll have a lot of replacements.
I purchased Bird-B-Gone II. The spikes run lengthwise, not across the spreaders. The spikes slide into a rail and the rail is affixed to the spreaders. I used on of the usual adhesives, such as Tough as Nails, and two stainless hose clamps on each spreader. Don't forget the masthead. Make sure the excess of the clamps doesn't stick out.
I couldn't wait to attach these beauties and pray that they work. While the boat was being rigged in the spring, the guffaws and laughter from the riggers could be heard everywhere, as well as an occasional curse, dues to being pricked by the Beauties. I just asked the boatyard not to turn me in to the Bird police. Actually the Bird-B-Gone folks call it a humane deterrent. Who cares, as long as it works. IT WORKED!!!!!! Once in a while I may get a high altitude sea gull fly by, but no CORMORANT POOP.
My mast on Rindasella gets stored every winter, so it doesn't get as much weather as others. However, those preventers have been up seven years or more and have gone through a few hurricanes. I replaces the clamps once. Enclosed you will find the brochure and instructions for Bird-B-Gone II. Hope they are still in business?
We also have a Pearson 35 on Kent Island, MD, at the foot of the Chesapeake Bay Bridge. I saw one CORMORANT swimming in the marina this summer, and a dock mate threw it some bread. I almost threw that fool into the water. I calmed down and explained what an Evil and Sinister creature they had fed. There seems to be far fewer down there. But I am always on alert.
Best of luck to David.
The various species of birds are a continuous nuisance to the boats on moorings in Plymouth Harbor, Plymouth, MA. The boat owners dilemma is predicated on the type of boat owned since sailboats attract different species of birds than powerboats. Our experience with sea birds started over 20 years ago when our first sailboat was moored in the harbor. We noted that the terns would leave the nearby beach and use our bow pulpit as a resting porch thus decorating our fore-deck and roller furling drum with droppings. We found that a pennant flag installed on the pulpit would discourage them on windy days but nothing would drive them off on windless days except our running forward waving our arms and shouting profanities at them. This exercise also amused or annoyed the boaters around us.
As we graduated to larger sailboats over the years our problems with birds grew in proportion. Instead of just terns on the bow pulpit, and as time went on, on the boom, we started to attract cormorants in the rigging. The resulting mess as compared to the terns is mouse droppings vs. elephant. We tried flags run up the mast to no avail and then plastic netting installed behind the spreaders with somewhat better results but with dubious aesthetics. We found the best solution was to run monofilament fishing line about 6 inches above the spreader from the stay to the mast and to install a spiked bar on the mast top to discourage the cormorants from landing there. Actually our hope was to make our craft more difficult to land on than the visiting sailboats whose captains were not expecting the nightly onslaught.
This seasonal battle continued until 1998 when we sold our final sailboat and purchased an Albin aft-cabin trawler. We were no longer bothered by cormorants but now became a target for seagulls by air and ducks by water. Again our theory became to make our boat less hospitable than those around us. We installed a "Gullsweep" on the pilothouse roof. This addition helped on windy days but otherwise did nothing to discourage the gulls. We then added several large plastic owls, one on the fore-deck and one on top of the pilothouse facing the stern of the boat since gulls land into the wind. The owls solved the problem as long as we moved them from side to side occasionally. We stay relatively clean while those around us get decorated nightly, or with gulls 24 ours a day.
Our final problem was the local flock of panhandling ducks. They liked to nest on swim platforms at night. We hung a line festooned with strips of plastic trash bags from out dinghy davits above the platform and tied a blowup owl to our stern rail to stare down at the interlopers. The ducks decided that pastures were greener elsewhere.
I will keep our other methods secret so that unsuspecting visitors to Plymouth Harbor will not make their boats less attractive than ours to the flying and swimming desecrators.
Seabirds, especially large seabirds with big footprints such as seagulls and ducks, aren't dumb. They roost on dark-colored boat canvas because dark-colored canvas soaks up the heat of the sun and is a warm roost. It continually amazes me that the average boater has not made that simple connection. So, there is a plethora of black, dark blues, maroons, browns and greens covering flying bridges and cockpits of power boats and mainsails, dodgers and cockpits of sailboats. Light colored, even white, canvas is the way to repel these feathered, fouling fowl. I use linen-colored Sunbrella on my tugboat to good advantage. Occasionally, a wren will alight, but that's about it for the bird problem. The linen color complements the teak trim very well. But, most boaters should skip the color coordination when selecting canvas to repel birds. Light colors do not build up damaging heat under them, as well. New Catalina sailboats supply a light gray canvas now, and Sea Ray has gone to a light tan for factory supplied canvas in my boating area of Southern California.
If you have a choice of dockage, an end tie attracts the most birds because it is the first roost encountered. Sea moorings are very problematic because they form islands that birds gravitate to for uninterrupted rest. Tall boats in a line of slips attract birds more than smaller, lower boats. Birds like to pick a high roost to watch for predators or enemies.
If you have a tall boat with a dark canvas cover on the fly bridge docked on an end pier, what can you do? One enterprising boating neighbor replaced his dark green top with bright white, then strung monofilament line about six-inches above the top. The lines were fastened to clear plastic rods about six-inches high above the top that were drilled to accept the monofilament strung from front to back of the top cover. Bird problem absolutely solved! Thirteen years and has served as a role model bird-poop test laboratory.
Fake owls, inflatable rattlesnakes or children's molded reptile or snake toys don't work at all. I have seen a seagull peck at an inflated rattlesnake and burst it. A string of multi-colored plastic pennants tied from fore-stay or mainmast of a sailboat to the topping lift or backstay and run about six inches above the mainsail cover does work, especially in windy areas. The constant movement of the colored pennants shoos away most any bird from alighting. There will always be bird fly-overs that dump their load wherever, so occasional soiling most anywhere will occur.
If a boat is used regularly and you are at the boat daily, birds will tend to bother you less, given the other protections cited. Above all, never feed wild birds! It is against California Dept. of Fish and Game law to feed birds unused or leftover bait. If you do feed birds such as ducks or seagulls from your boat, count on them approaching you every time you come to your boat. They are creatures of habit. They will foul your swim platform because it is now their new feeding stop. Turn your boat around in your slip with the transom to the dock if birds have selected your swim platform as a regular roost. Stretched monofilament tied to removable spacer bars can prevent birds from alighting on a swim platform or in a cockpit, covered with canvas or open.
Observe birds, not what flushes then and what doesn't, and counterattack accordingly. You can win with appropriate defenses regularly applies that won't take much time or effort on your part. Getting a new boat? Plan ahead your canvas color choice and other tricks to install at commissioning. If you have a mast with spreaders for flag halyards on your powerboat, install the monofilament line just above the spreaders. Look for any high horizontal roosting spots on the boat and plan from the launch date to get your boat bird-proofed.
Finally, clean up bird messes immediately upon finding them, otherwise corrosive chemical damage to finishes will occur. Birds also are attracted to other bird messes, which are a sign to them of a good, undisturbed place that fosters long roosting. These techniques have been reinforced by my observations over many years of boating in Minnesota, Wisconsin, Illinois and coastal California waters. They do work!
We are aboard a 41' Trawler and during the winter months the marina is inundated with blackbirds. They shop in local dumpsters and bring their selections, i.e. chicken wings, pizza, french fries, back to the boat to snack on & then…You know what! Our upper deck resembled the bottom of a neglected bird cage. My husband took clear fishing line filament and strung it from the top of the mast out to the spreaders and along the boom about 5" above.
Another boat put fishing line from the bow flagstaff along just above the rails. The birds will not fly into the line. But…birds are clever…if they can't fly in some will walk from the pier, out along the dock lines onto the boat and still sit on the rails…GOOD LUCK!
Please see out partially completed web site at BIRDOFF.com for pictures of installations on boats.
Thank you for your invitation to review products to deter birds from boats. This is very timely for me, as I have been testing and refining this product for two years and am now ready to come to market. The product name is BIRDOFF. BIRDOFF is designed to deter birds from landing on the railings, bimini supports, etc. BIRDOFF will dramatically reduce bird droppings on boats. Some of its features are as follows:
- 1. Easy to install and remove
- 2. Will not harm birds
- 3. Does not detract from boats' appearance
- 4. Does not require any damage to boat for installation
- 5. Does not harm the environment
- 6. It's reusable
BIRDOFF come complete, in a kit that will protect approximately 45 LF of straight railing. (curved railings require closer placement of clips) BIRDOFF is presently available for 1 inch diameter railings.
P.S. I am enclosing a display sample and two BIRDOFF kits. Our web site will be complete in a week or two.
Of all the occurrences that can catapult a boat owner into a fury, the use of his boat as a convenient potty by diarrheal seagulls has to be very high on the list. Watching from our front window as the gulls evacuate their bowels on our boat, which is on a buoy in the bay, has on occasion reduced this otherwise semi-sane person to gibberish level of Clouseau's boss in the Pink Panther movies.
This situation brought on a determination to devise a system that would make our boat so unattractive to the gulls that they would take their potty business to the boat of our good friends who tie to a buoy across the bay. We certainly didn't wish them any distress, but better them than us.
There are any number of bird scaring devices advertised in the magazines but they all require 110-volt current backed up by a giant generating facility, not available in the middle of our bay.
The first attempt at inventing a seagull deterrent system, or SGDS, involved our neighbor, a retired electronics engineer. After a gin-fueled evening of invention, we decided that we would somehow record an eagle's scream on an electronic chip, attach it to a speaker, and hook the works to a small battery and timer chip. This device would emit a scream of "Death to Seagulls" at appropriate intervals. We are confident that the only unknowns in our plan were how often to activate the terrifying scream and how big a battery would be needed. This plan got only as far as the test mule stage when we determined that in order to last two weeks (one of our design criteria), the battery would have to be inordinately large. So much for technology.
The next approach to a viable SGDS was to purchase from the garden supply catalog a couple of the yellow 18" plastic inflatable balls that go by names such as "Scare Eyes" or "Terror Eyes." They have eyes painted on four sides and are theoretically always casting a venomous gaze on landing birds regardless of their angle of approach. Our experience showed us that hanging a couple of these things over the deck will indeed repulse potty bound birds for a couple of weeks or until a windstorm rips the mooring eyes out of the scare eyes, whichever comes first. Adding zest to this system is a post windstorm tour of the bay in the dinghy searching for the escapee, which is rarely salvageable. Scratch this, although it was definitely an improvement on the first idea. A good shot, but no cupie doll.
And then one day while surveying a pile of empty shiny plastic bladders from five-liter wine boxes (I can't throw anything away!), the lady of the house said "why don't we use the roller type fabric cutter to cut one inch strips from the bottom of the bladder to about an inch from the top where the hard plastic nozzle is located. Then we'll attach a short piece of cord and tie them to a line which we'll string from the bow railing to the top of the mast and down to the stern railing?" The obvious name for this SGDS was "Winebirds."
The Winebird system, to our delight, has proven to have an efficacy rating of about 90% and after a couple of test summers shows no signs of diminishing effectiveness. As a result of this success, the lady of the house and former First Mate has been promoted to "Captain of the Ship!" We have not asked our friends across the bay of they have experiences an increase in visitations from winged gulls!
I am a BoatU.S. policy holder and I thoroughly enjoy the Seaworthy damage avoidance report. I was glad to see the article on bird damage. I boat on the south shore of Lake Erie where we have several different problems with birds. The most serious is with swallows lighting on bow rails of powerboats and lifelines of sailboats. These migratory birds hit Lake Erie in July and August each year. They are very social so you can find as many as fifty on a single boat. They sit side by side and chat with each other and, of course, do their business. What they can do from Sunday afternoon to Friday afternoon is incredible and requires a significant effort to clean up. It is a very frustrating and emotional issue with boaters.
About two years ago I developed for my sailboat to prevent swallows from lighting on my lifelines. For two seasons it has proven to be very effective. Last year I developed a system for powerboat bow rails and tested it on three boats over the 2001 season. It was also very effective. In fact, I had many power boaters requesting sets. The concept is very simple. I basically suspend a nylon monofilament line one inch above the bow rail or lifeline. Doing this requires different components for bow rails and lifelines. Enclosed are pictures of the bow rail version that we tested last summer. This system works, it is easy to install and remove and it is low profile. The boaters who tested the system last summer left them on all during the bird season.
It have just recently gone into production of the powerboat bow rail product and will have the product available for sale in early March (the final design of the bow rail clip is lower profile than the ones in the pictures). This is my first venture into my own business. I plan to market over the Internet and through marine stores and marinas. Systems will be available for seven-eighths inch, one inch and one and one-quarter inch bow rails. If boaters are interested in this product, called "No Birds", they can contact me via Internet at BOATZSTUFF@aol.com. I hope to have a website by the middle of February but don't have one at this time.
I plan on introducing the sailboat version in 2003. If you have any questions regarding the "No Birds" product please give me call. I am a struggling entrepreneur and a little free publicity in your magazine would be a great help. Thanks in advance for your consideration.
PS A patent has been applied for.
I was very interested in the "Jonathan Livingston…" article which appeared in your January 2002 issue. I have a variation of the problem addressed in that article.
On November 2, 2002, a flock of about 50 black vultures landed on my waterfront property and within a few minutes, about 15 of them flew from my pier onto my 21.9 Shamrock, which is on a lift. There was nothing to attract them to the boat, as it had been thoroughly cleaned two days before following a fishing trip.
I quickly dressed and ran out to chase them and literally had to swing a boat hook to get the last two to leave the boat. In a matter of ten minutes they had done several thousand dollars worth of damage, to wit: pecked dozens of holes and removed stuffing from the port, starboard, and stern holsters; did the same to the windshield; tore holes in the canvas tournament top; and as a final touch, ripped out the windshield wiper blade. Of course there was vulture dirt from top to bottom.
They returned on a few occasions prior to my having the damage repaired and I now have a full winter cover over the boat.
As in your article, how do I prevent this? If the neighbors don't mind and if I am here when the vultures arrive, I could try using "shellcrackers" from a shotgun. Some type of remote wireless alarm such as is available for doorbells with a range of 300 feet?
I have a serious problem as I dread the reoccurrence of the attacks. Perhaps your April issue will be helpful. Please contact me if you have any solutions.
Our main problem at our dock in the winter is not seagulls as blackbirds. I found that leaving the stereo on low (we have speakers on the fly bridge of our little trawler) reduces the number of birds and the length of time they may sit and socialize. Music selections? Country western worked well for a while, but then lost effect. I switched to RAP and turned up the base and it seemed to do the job. I set the volume just loud enough to tickle their feet. Maybe a sub-woofer would help? Every now and then we find one that sort of rocks with the music.
One of your subscribers, Mr. Loewenberg, suggested we send information on our product to you. It is a Gullsweep and the purpose is to keep gulls from fouling docks, decks, and canvas covers.
Since we manufacture the Gullsweep--of which Mr. Loewenberg has three--we felt it better to send you a copy of a letter we received for you to use in your "Plea to Clever Readers" article, if you so choose [from Peter Phipps below].
I have two Gullsweeps mounted on my fishing/sport boat moored on a lake in northern Vermont (one on the bow and one on the main cabin.) They are the only devices I have found to be effective in keeping gulls off the boat when left unattended for up to weeks at a time. I have recommended them highly and to several of my "neighbors" and fellow boaters on the lake and many, having witnessed my success, now use them. Keep up the good work.