Humane fish farm predator deterrents
Using artificial intelligence to provide long-term effectiveness and high animal welfare standards
by Ace Aquatec, Scotland
Fish farming has come under immense pressure in recent times due to a lack of familiarity with the industry, misinformation, and even headline grabbing documentaries.
In this article, we would like to challenge this narrative, because when done correctly, aquaculture can not only be a sustainable way to meet the growing needs of a burgeoning population, it can also be beneficial to the local communities and ocean health in general.
Ace Aquatec has spent many years on research and development to help farmers adopt responsible marine solutions. It is continuously seeking out and developing the best science and technological innovations to bring to the marine world, while keeping its focus on local partnerships and personal customised solutions.
Alternative to barrier acoustic deterrent devices (ADDs)
In 2001 John Ace-Hopkins developed a completely new method to keep seals from fish farms: the A.N.S.S. stood for All New Silent Scrammer, and it represented a completely radical departure from all previous deterrents that had come before it.
It emerged from an all too familiar debate that started in Canada and USA and made its way across the Atlantic. Infamous acoustic barrier systems were creating continuous noise at volumes capable of causing hearing impairment, which were also potentially disrupting marine wildlife that was not the intended target.
John Ace Hopkins was a polymath with a degree in animal biology and a good background in engineering. His solution to the cycle of predation was to explore three novel concepts, in an all-new approach to seal attacks of fish farm cages:
- Focus on the 'quality' not quantity of sound - When discretely produced, a brief, low average volume pulse was capable of eliciting a startle reflex. Uniquely, it became more effective the less it was heard.
- Conditioned avoidance - he manipulated seal behaviour by creating low volume pre-tones before the startle sound.
- Triggering devices - by responding only to predation, he created more effective targeted sounds which caused seals to avoid an area.
Ace Aquatec has remained true to this philosophy ever since, and it has gone on to introduce some state-of-the-art hardware improvements that have perfected the ASR (acoustic startle response) and ESR (electric startle response) deterrent approach.
In 2012 it began work on a lower frequency (pitched) device which would not be in the hearing range of porpoises but could be heard by seals. This provided us with two systems, the RT1 which was low pitched (0.8-5khz), and the US3 which was mid pitched (8-11khz).
The minimal startle sound creates a deterrent which is effective over the long term without harming animal hearing; something that incumbent technology couldn't achieve.
The company has pioneered ASR (acoustic startle response) deterrents that work by changing behaviour rather than by building an acoustic barrier (the old style ADDs), and our US3 and RT1 acoustic models were recognised, with a SAIC award for innovation for providing a step forward in both welfare and efficiency compared to traditional acoustic devices.
Ace Aquatec's ASR devices, which meet the requirements from Marine Scotland for modulated frequencies and low average volumes and can be deployed without EPS licences, are clearly audible to target species, such as seals, but are less audible to protected cetaceans.
The three key elements of the Ace conditioning signal are the low duty cycle (on/off periods), the low average volume (less energy output) and the low frequency (pitch).
The recent advances in acoustic technology embraced by Ace Aquatec enable farms to take a blended approach to predator control. The most successful safeguards against predation will be a combination of new generation acoustics, reinforced anti- predator netting, and good farming practices. When taken together, such measures will ensure that farms, fish and other marine mammals all thrive within the new regulatory framework.
Triggering the flight reflex
The acoustic startle reflex is a well-studied phenomenon, which John Ace-Hopkins and Gavin Haywood first suggested should be explored for seal mitigation back in 1996 in Management of Seal Predation, at the Scottish Aquaculture Conference. First explored in rats (Moyer 1963; Fleshler 1965; and Pilz and Schnitzler 1996) the startle reflex was provoked by a precisely defined onset and peak in sound, and voltage gradient in electric field experiments.
The latter work was continued by Dr David Thompon and Dr Jeffrey Lines at SMRU and was adapted into Ace's electric startle systems. Ace Aquatec have gone on to develop patented ESR (electric startle response) nets, decoy/mort fish, and surface E-fences for our customers. Working together as a single mitigation system, the acoustic and electric startle systems provide a single learning event which causes seals to avoid foraging for food around a farm's cages.
This technology was a runner up at the Marine Scotland Welfare awards in 2017 and Compassion in World farming has added a case study on Ace Aquatec's complete deterrent solution, in order to showcase the significant advances in animal welfare and huge reductions in fish mortality as well as impact on non-target species.
The Marine Mammal Protection Act (MMPA) prompted many fish farms to take a closer look at what measures they're taking to reduce impact on their local marine environment, and Ace Aquatec's solution provide an environmentally responsible approach to reducing seal interactions on farms without negatively impacting the seals or the surrounding wildlife.
Identify predators using artificial intelligence
Based on more than 20 years of research, Ace Aquatec's deterrents now combine acoustic and electric systems, with machine learning day and night vision camera triggers in order to provide long-term effectiveness and high animal welfare standards.
The thermal imaging camera combined with artificial intelligence (AI) automatically triggers the company's deterrents when a seal or sea lion is approaching, meaning the system only activates when needed, while avoiding an event if a non-target species is detected.
This software also includes an automatic ramp down period after every activation and an intelligent awareness of other systems in operation, which reduces duty cycle or total average transmission volume.
The benefit of this thermal camera triggered automation is a significant reduction in the amount of sound being produced by each farm site, without exposing fish to a higher risk of predator attacks.
Minimising environmental impact
In addition to providing a low frequency option the company saw another two opportunities to improve our environmental impact:
- Opportunity #1: reduce how often its deterrents are active.
- Opportunity #2: reduce acoustic energy output when the deterrents are active.
The benefit of this AI camera triggered automation is a significant reduction in the amount of sound being produced by each farm site and more importantly, this is done without exposing their fish to a higher risk of predator attacks.
The outcome of achieving this project's goal was a decision to programme Ace Aquatec's deterrents to operate intelligently with awareness of each other rather. This means that in future if there is more than one deterrent installed at a farm site, they will be able to act as a coordinated group.
The company's roadmap for the years going forward include continued investment into research and development and expand these findings into several global key markets. We're seeing a growing demand across the globe for more ethical and sustainable methods of fishing and believe our latest technology developments will help ease this transition.
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