Hi All
Many of us who love our marine environments have become alarmed at the explosion in numbers of sea urchins in many countries which is having a devastating effect on kelp beds. In many places the kelp beds have been eaten down to the roots and the kelp cannot regenerate as a result if the continual grazing. So much of the health of a marine ecosystem relies on the presence of healthy kelp beds, not to mention the food sources and livelihoods of many people worldwide.
Healthy sea urchin has high value roe making it economic for a diver to harvest them. Explosions in numbers of sea urchin result in all the available kelp being eaten and then the roe shrivels and loses its commercial value. Control of those highly damaging numbers of urchins then relies on either volunteers or paid divers to do the work of destroying them in situ or removing them.
In Australia, as in some other counties, it is difficult to find volunteers and the cost of paying certified divers is very high. This means the destruction of those incredibly vital kelp beds goes virtually unchecked. In a place like Tasmania where we currently are to conduct our trials, 95% of the kelp beds have disappeared since the 1970s. While some of that loss is from global warming, much of that damage is purely as a result of invasive urchins exploiting warmer waters to expand their range. Government organizations and industry bodies have done little to address the problem.
At Downdeepdrones, we are strong believers that citizen science can provide many of the solutions required for healthy environments of all sorts. We see ROVs, armed with the right tools being able to provide a cost effective way to potentially control urchin numbers either by culling or harvesting.
We have a number of prototypal tools that can be attached to an ROV that should be able to kill an urchin ranging from Blue Robotics M200 powered circular saws to drills and repeating hammers controlled by a Thruster Commander. We also have a more rudimentary range relying on the thrust of the ROV to drive a tool through the shell of an urchin and soon will be conducting field trials to determine which, if any tools, works best and what further methods need to be developed. After more than 10 years of making small ROVs and tools to attach to them, we are more than hopeful we can make at least one too that is fit for purpose.
In the interest of making the lowest price tools available on the cheapest functional underwater drone, we have adapted the tools to fit onto an entry level unit. The limitations of such a somewhat toy grade and fault prone unit in such a tough operating environment are already apparent and we can see, budget allowing that the best workhorse ROV to power and carry these tools would be a BR2 Heavy. Currently, the high cost of developing and trialling these tools has depleted our resources and we don’t have a BR2 ROV to use.
We have therefore started a Kickstarter campaign that hopefully will see that change. If you would like to see this trial be given the best chance to succeed, we would very much welcome your support. Our first trials of the tools in the field starts early next month.
https://www.kickstarter.com/projects/underwaterrobot/sea-urchin-culling-harvesting-tools-for-robots
We will be posting regular updates here to share what we are learning from our trials and hopefully even inspire some of you in the BR community to develop your own tools to cull or harvest sea urchins or perhaps any other invasive marine species. If you have any good ideas that you would like us to consider and possibly trial, please don’t hesitate to let us know.
Attached are a few videos and photos of some of the tools under development.
John Griffiths
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