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Some whale calls share low-frequency bands with noise from ships, creating the risk that human activity can mask sounds animals use to communicate. A loop-blade propeller developed by Sharrow Marine is intended to reduce one source of vessel noise—propeller cavitation—but current reporting does not establish that it helps whales hear one another or improves whale populations.
How vessel noise can interfere with whale communication
Whales use sound to communicate in an ocean where sound from shipping and other human activity can add background noise. When vessel noise overlaps the frequencies of animal calls, it can make those calls harder to detect. The degree of interference depends on the species, frequency, vessel, and situation; it does not mean whales everywhere are unable to hear one another. Popular Science’s October 3, 2026 report describes the issue as acoustic interference.
What Sharrow’s loop-blade propeller is designed to change
Greg Sharrow, founder and CEO of Sharrow Marine, developed the design after exploring ways to reduce drone noise for filming a violinist within an orchestra. The “200 years” in the headline refers to the report’s account of the familiar screw-propeller lineage, which dates to patents in the 1830s; it does not mean the new propeller took two centuries to invent. Popular Science recounts that history and the inventor’s origin story.
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A fast-spinning conventional propeller can create cavitation: bubbles form around the blades and collapse, producing sound. Sharrow’s blades form loops rather than ending in open tips. The company says this geometry reduces tip vortices associated with conventional blade tips and is intended to reduce cavitation. That is the proposed mechanism, not proof of a benefit to whales. Sharrow describes its engineering and performance claims on its performance pages.
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- Manufacturer part number 8M0055535
What noise-reduction evidence is available
Popular Science reports that Sharrow claims underwater noise reductions ranging from 3 to 24 dB across 10 Hz to 20,000 Hz in some tests. The company’s reported reductions vary by frequency, application, and operating condition. These are company-reported measurements relayed by the article, not a universal reduction for every boat, nor evidence that whale communication improved. Sharrow’s own performance material also presents company-authored product and vessel-test claims.
The available accounts do not provide a primary peer-reviewed study verifying the reported underwater noise figures or demonstrating a population-level whale benefit. A separate company-hosted account of a BoatTEST comparison reports results for one World Cat 325 DC with twin Yamaha 300-hp engines and propellers configured for that boat. In that specific test, the account reports 21.7 mph at 3,000 rpm, 14.8 gallons per hour, and 1.5 miles per gallon with Sharrow propellers. Those figures are tied to that vessel and setup; they do not establish performance for other boats or an ecological outcome. The Sharrow-hosted BoatTEST account does not show a publication date.
Rank #2
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- ★Size&Material:10 1/2 Diameter x 13 Pitch, identical to original OEM ones;Rotation: Right; Blade:3 ; Color: Black; High Quality Aluminum
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What Ocean Alliance observed—and what it did not establish
Ocean Alliance CEO Iain Kerr outfitted a boat with a Sharrow propeller and took it on a 75-mile trip, according to Popular Science. Kerr described lower noise and vibration and better fuel efficiency. This is a field observation reported by Kerr, not a controlled measurement of underwater sound. It also does not show that whales heard one another better, or that their health or populations changed.
The same report says more testing is needed, particularly as the technology is applied to larger vessels. In a dated company announcement, Sharrow Marine and VEEM reported a testing milestone for an inboard prototype on a 64-foot Viking vessel on April 29, 2024, and said they planned to move toward production and sales. That announcement records a prototype milestone and intended next steps, not confirmation of current availability. See the Sharrow–VEEM announcement for its account.
Rank #3
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- ★Material & Characteristic: High Quality Aluminum,Vacuum Casting，Five-layer Propeller surface processing;The heat-treated paddle blade has high toughness and is not easy to break
- ★Outstanding Quality: Based on strict quality control ,our propellers are extremely durable without sacrificing top speed,acceleration or rmps,reduce the wear and tear on your engine and fully-fuel efficiency. Better speed and save money for you!
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Why a quieter propeller is only one possible lever
University of New Hampshire acoustic ecologist Michelle Fournet, quoted by Popular Science, considers vessel-noise reductions a useful direction while calling for further testing. The report also points to slower vessel operations and quiet intervals without vessel traffic as complementary ways to address chronic noise. The sources do not provide a controlled, head-to-head comparison of these approaches.
- Measure sound by frequency and operating condition. An overall noise figure cannot show whether a reduction occurs where a particular animal’s calls are vulnerable to masking.
- Test across vessel sizes and uses. Results from a particular boat or prototype do not establish how the design performs at larger scales.
- Assess performance as well as noise. Fuel use, speed, and handling matter to operators, but vessel-test results alone do not demonstrate ecological benefit.
- Measure ecological outcomes independently. A quieter vessel is a plausible contribution to reducing interference; evidence that animals communicate more successfully or populations benefit requires separate observation.
For now, the Sharrow propeller is a promising noise-reduction approach with company-reported test claims and an early field observation—not a proven fix for whale communication. A credible assessment of its wider value depends on further acoustic measurements and independent ecological evidence.
Quick Recap
Best Value
- 14.5" diameter, 19" pitch, right-hand rotation
- For use with 90-115hp Command Thrust and 150-300hp Mercury/MerCruiser engines
- Aluminum with black finish
- World's best-selling aluminum boat engine propeller design
- Provides the perfect balance of performance, durability and value
Rank #4
- ★Model Characteristic: 10 3/8 x 13 OEM ones for Outboard Engines 30-60HP, 13 Spline Tooth,Ref. Parts Number 48- 73136A45
- ★Size&Material: 10 3/8 Diameter x 13 Pitch,identical to original OEM ones;Rotation: Right; Blade:3 ; Color: Black; High Quality Aluminum
- ★Service Promise: Please refer to below product description for detailed engines application.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
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