@hkon_nergrd - Hi Hkon, you can read more about GreenWave's guidance on what type of lines to use in ocean farming in the course on Gear Selection, and the lesson on Lines. However, you're right, many of the lines we recommend, and that farmers have had good luck with in the past, are made from plastics. I know there are some folks experimenting with using hemp and manila lines, among other natural fibers, trying to reduce a reliance on plastics, so this is an area of interest and research.
I'm looping @tamsen_peeples into this discussion because I know she was experimenting with cotton seedstring in place of nylon twine. Perhaps @david_bailey, do you have any other suggestions?
@ian_mcfarland - I recently attended at talk by @zach_moscicki at NACE in Portland, ME, talking about his team's research into using fiberglass composite rebar in place of lines that will break if struck by a marine mammal, before entangling it. Perhaps he could offer more insight here?
I've also heard @scott_lindell from WHOI report that although marine mammal entanglements are tragic, given the scale of the ocean farming they're relatively rare. Keeping lines under tension is the primary strategy for reducing entanglements, though clearly in areas of known migration and concern, other precautions may also be necessary.
@lindsay_olsen - the idea of using a natural fiber line is appealing in some respects, but likely limited to seed string where a short service life is useful or in the farming of a biofuel feed stock where the growlines and the crop can be put into the bio-conversion process providing a huge saving in harvest effort. For most other applications where the re-use of the growlines is expected, then synthetic fibers seem a logical choice where we are expecting to get 5 to 10 years of service. A lot depends on their handling during harvest and during off-season storage. If left in the sun on dry land they will degrade, start shedding fibers, and fail fast. Key to preventing the plastic pollution problem is retiring and recycling line before it begins to look ratty because by then the strength has already been compromised.
Regarding entanglement risk, maybe we've been lucky, but either due to the inshore locations or through the the use of pretensioned offshore arrays, we have not seen any problems. But I do worry about some proposed designs that present an obstacle course of mooring lines that present an unfortunate and unnecessary challenge to marine mammals.
@lindsay_olsen - Thank you for very good answers. I have actually seen research reports claiming that when non-plastic ropes are being used, mussels grow much faster and become significant bigger. Supporting other research claiming that microplastic is bad for reproduction. This reseach with non-plastic ropes was done in the Baltic sea.
I have also been in touch with a company that is trying to produce a biodegradable rope, but last time I heard from them they were still on test-stage..
But I guess you can avoid the microplastic problem significantly by taking care of the rope, and replace it in time
@hkon_nergrd - Hi Hkon, you can read more about GreenWave's guidance on what type of lines to use in ocean farming in the course on Gear Selection, and the lesson on Lines. However, you're right, many of the lines we recommend, and that farmers have had good luck with in the past, are made from plastics. I know there are some folks experimenting with using hemp and manila lines, among other natural fibers, trying to reduce a reliance on plastics, so this is an area of interest and research.
I'm looping @tamsen_peeples into this discussion because I know she was experimenting with cotton seedstring in place of nylon twine. Perhaps @david_bailey, do you have any other suggestions?
@lindsay_olsen -
Marine life entanglement (especially migrating whales) is a cause for concern. Anyone have any insight into farm designs that avoid this issue?
@ian_mcfarland - I recently attended at talk by @zach_moscicki at NACE in Portland, ME, talking about his team's research into using fiberglass composite rebar in place of lines that will break if struck by a marine mammal, before entangling it. Perhaps he could offer more insight here?
I've also heard @scott_lindell from WHOI report that although marine mammal entanglements are tragic, given the scale of the ocean farming they're relatively rare. Keeping lines under tension is the primary strategy for reducing entanglements, though clearly in areas of known migration and concern, other precautions may also be necessary.
@lindsay_olsen - gold! Thanks for sharing
@lindsay_olsen - the idea of using a natural fiber line is appealing in some respects, but likely limited to seed string where a short service life is useful or in the farming of a biofuel feed stock where the growlines and the crop can be put into the bio-conversion process providing a huge saving in harvest effort. For most other applications where the re-use of the growlines is expected, then synthetic fibers seem a logical choice where we are expecting to get 5 to 10 years of service. A lot depends on their handling during harvest and during off-season storage. If left in the sun on dry land they will degrade, start shedding fibers, and fail fast. Key to preventing the plastic pollution problem is retiring and recycling line before it begins to look ratty because by then the strength has already been compromised.
Regarding entanglement risk, maybe we've been lucky, but either due to the inshore locations or through the the use of pretensioned offshore arrays, we have not seen any problems. But I do worry about some proposed designs that present an obstacle course of mooring lines that present an unfortunate and unnecessary challenge to marine mammals.
Cliff
@lindsay_olsen - Thank you for very good answers.
I have actually seen research reports claiming that when non-plastic ropes are being used, mussels grow much faster and become significant bigger. Supporting other research claiming that microplastic is bad for reproduction. This reseach with non-plastic ropes was done in the Baltic sea.
I have also been in touch with a company that is trying to produce a biodegradable rope, but last time I heard from them they were still on test-stage..
But I guess you can avoid the microplastic problem significantly by taking care of the rope, and replace it in time
@lindsay_olsen -
Marine life entanglement (especially migrating whales) is a cause for concern. Anyone have any insight into farm designs that avoid this issue?
@ian_mcfarland - I recently attended at talk by @zach_moscicki at NACE in Portland, ME, talking about his team's research into using fiberglass composite rebar in place of lines that will break if struck by a marine mammal, before entangling it. Perhaps he could offer more insight here?
I've also heard @scott_lindell from WHOI report that although marine mammal entanglements are tragic, given the scale of the ocean farming they're relatively rare. Keeping lines under tension is the primary strategy for reducing entanglements, though clearly in areas of known migration and concern, other precautions may also be necessary.
@lindsay_olsen - gold! Thanks for sharing
@lindsay_olsen - the idea of using a natural fiber line is appealing in some respects, but likely limited to seed string where a short service life is useful or in the farming of a biofuel feed stock where the growlines and the crop can be put into the bio-conversion process providing a huge saving in harvest effort. For most other applications where the re-use of the growlines is expected, then synthetic fibers seem a logical choice where we are expecting to get 5 to 10 years of service. A lot depends on their handling during harvest and during off-season storage. If left in the sun on dry land they will degrade, start shedding fibers, and fail fast. Key to preventing the plastic pollution problem is retiring and recycling line before it begins to look ratty because by then the strength has already been compromised.
Regarding entanglement risk, maybe we've been lucky, but either due to the inshore locations or through the the use of pretensioned offshore arrays, we have not seen any problems. But I do worry about some proposed designs that present an obstacle course of mooring lines that present an unfortunate and unnecessary challenge to marine mammals.
Cliff
@lindsay_olsen - Thank you for very good answers.
I have actually seen research reports claiming that when non-plastic ropes are being used, mussels grow much faster and become significant bigger. Supporting other research claiming that microplastic is bad for reproduction. This reseach with non-plastic ropes was done in the Baltic sea.
I have also been in touch with a company that is trying to produce a biodegradable rope, but last time I heard from them they were still on test-stage..
But I guess you can avoid the microplastic problem significantly by taking care of the rope, and replace it in time