Genady Posted February 9, 2022 Share Posted February 9, 2022 (edited) Since appearing in our area about 15 - 20 years ago, the invasive lionfish became a common resident on our reefs. Contrary to the wide-spread anti-lionfish propaganda about its many dangers to the local marine environment, such as "Nothing eats lionfish", "Local fish don't know that it's a predator", "It eats everything", "It multiplies uncontrollably", etc., it did not cause any damage to the coral reef or to its inhabitants. It rather found its eco-niche and lives peacefully with - i.e. eating and being eaten by - other fishes. It added an exotic element to our underwater experience, though. Please meet - the lionfish: Edited February 9, 2022 by Genady Link to comment Share on other sites More sharing options...
beecee Posted February 9, 2022 Share Posted February 9, 2022 Undeniably along with coral bleaching, the greatest danger to Australia's Great Barrier Reef, is the "crown of thorn starfish" https://www.barrierreef.org/the-reef/threats/Crown-of-thorns starfish Link to comment Share on other sites More sharing options...
Genady Posted February 9, 2022 Author Share Posted February 9, 2022 3 minutes ago, beecee said: Undeniably along with coral bleaching, the greatest danger to Australia's Great Barrier Reef, is the "crown of thorn starfish" https://www.barrierreef.org/the-reef/threats/Crown-of-thorns starfish It is not invasive, is it? Link to comment Share on other sites More sharing options...
beecee Posted February 9, 2022 Share Posted February 9, 2022 3 minutes ago, Genady said: It is not invasive, is it? Yes it is as far as I know. Will do some checking in the meantime. 4 minutes ago, beecee said: Yes it is as far as I know. Will do some checking in the meantime. Seems I maybe wrong......................... https://phys.org/news/2019-02-dreadful-discovery-crown-of-thorns-starfish-silver.html extract: "The crown-of-thorns is an infamous pest, responsible for the loss of immense stretches of coral throughout the Indo-Pacific region, especially on Australia's Great Barrier Reef. It's been the object of concern and media exposure for a couple of decades. Many people assume that because it does so much harm, the crown-of-thorns must be an invasive species, but it's not. "It's native to the Pacific," Allen said. "They're widespread and we now know that there are four species." Link to comment Share on other sites More sharing options...
Genady Posted February 9, 2022 Author Share Posted February 9, 2022 1 hour ago, beecee said: Yes it is as far as I know. Will do some checking in the meantime. Seems I maybe wrong......................... https://phys.org/news/2019-02-dreadful-discovery-crown-of-thorns-starfish-silver.html extract: "The crown-of-thorns is an infamous pest, responsible for the loss of immense stretches of coral throughout the Indo-Pacific region, especially on Australia's Great Barrier Reef. It's been the object of concern and media exposure for a couple of decades. Many people assume that because it does so much harm, the crown-of-thorns must be an invasive species, but it's not. "It's native to the Pacific," Allen said. "They're widespread and we now know that there are four species." If they are right and the eutrophication is the main cause of the COTS' population explosion, then I don't know what you guys can do about it. Corals vs agriculture, hmm... At least we don't have that problem here. All the rest, yes - warming, acidification, overfishing, mechanical damage to the reef by boats and divers, - but not eutrophication. Link to comment Share on other sites More sharing options...
beecee Posted February 9, 2022 Share Posted February 9, 2022 (edited) 18 minutes ago, Genady said: If they are right and the eutrophication is the main cause of the COTS' population explosion, then I don't know what you guys can do about it. Corals vs agriculture, hmm... At least we don't have that problem here. All the rest, yes - warming, acidification, overfishing, mechanical damage to the reef by boats and divers, - but not eutrophication. While significant damage has already been done, it as been found that injecting vinegar into the COTS will kill them. It is though time consuming as each COTS is injected individually with this vinegar mixture by trained divers, to avoid harming the surrounding system. https://www.barrierreef.org/the-reef/threats/Crown-of-thorns starfish#:~:text=Crown-of-thorns starfish control,t harm the surrounding ecosystem. Edited February 9, 2022 by beecee Link to comment Share on other sites More sharing options...
Genady Posted February 9, 2022 Author Share Posted February 9, 2022 1 hour ago, beecee said: While significant damage has already been done, it as been found that injecting vinegar into the COTS will kill them. It is though time consuming as each COTS is injected individually with this vinegar mixture by trained divers, to avoid harming the surrounding system. https://www.barrierreef.org/the-reef/threats/Crown-of-thorns starfish#:~:text=Crown-of-thorns starfish control,t harm the surrounding ecosystem. Do the numbers work out? Population and population growth of the COTS on one hand, number of trained divers and their rate of injecting the COTS on the other? Will it make even a dent in the COTS population? Divers kill lionfish in this part of the world, but it doesn't make any difference in the lionfish numbers. It tastes good, though. Link to comment Share on other sites More sharing options...
beecee Posted February 9, 2022 Share Posted February 9, 2022 11 minutes ago, Genady said: Do the numbers work out? Population and population growth of the COTS on one hand, number of trained divers and their rate of injecting the COTS on the other? Will it make even a dent in the COTS population? Divers kill lionfish in this part of the world, but it doesn't make any difference in the lionfish numbers. It tastes good, though. Good question. All I can say, is I hope so. Otherwise we may lose one of the seven natural wonders of the world. Link to comment Share on other sites More sharing options...
Genady Posted February 10, 2022 Author Share Posted February 10, 2022 A slow dance with a quick ending. So much to the "Nothing eats lionfish" slogan. This video: Link to comment Share on other sites More sharing options...
dimreepr Posted February 10, 2022 Share Posted February 10, 2022 Link to comment Share on other sites More sharing options...
Genady Posted February 10, 2022 Author Share Posted February 10, 2022 23 minutes ago, dimreepr said: Wrong thread? Link to comment Share on other sites More sharing options...
dimreepr Posted February 10, 2022 Share Posted February 10, 2022 3 minutes ago, Genady said: Wrong thread? Is it? -2 Link to comment Share on other sites More sharing options...
Genady Posted February 10, 2022 Author Share Posted February 10, 2022 Just now, dimreepr said: Is it? I don't know. Can you explain? Link to comment Share on other sites More sharing options...
dimreepr Posted February 10, 2022 Share Posted February 10, 2022 1 minute ago, Genady said: I don't know. Can you explain? Change is inevitable, the lionfish isn't... -1 Link to comment Share on other sites More sharing options...
Genady Posted February 10, 2022 Author Share Posted February 10, 2022 Just now, dimreepr said: Change is inevitable, the lionfish isn't... Would be helpful if the post comes with some explanation about what it is doing in the thread, so others don't need to check the link if they're not interested. I think, it is also a rule here. Anyway, is there anything about lionfish or invasive species in the video? What? 1 Link to comment Share on other sites More sharing options...
dimreepr Posted February 10, 2022 Share Posted February 10, 2022 2 minutes ago, Genady said: Would be helpful if the post comes with some explanation about what it is doing in the thread, so others don't need to check the link if they're not interested. I think, it is also a rule here. Anyway, is there anything about lionfish or invasive species in the video? What? The rule here is, attack the argument, not the lionfish... -1 Link to comment Share on other sites More sharing options...
Genady Posted February 10, 2022 Author Share Posted February 10, 2022 1 minute ago, dimreepr said: The rule here is, attack the argument, not the lionfish... Which argument are you attacking? Link to comment Share on other sites More sharing options...
dimreepr Posted February 10, 2022 Share Posted February 10, 2022 1 minute ago, Genady said: Which argument are you attacking? The myth of invasion... Link to comment Share on other sites More sharing options...
Genady Posted February 10, 2022 Author Share Posted February 10, 2022 4 minutes ago, dimreepr said: The myth of invasion... OK. I only wish you would make it clear in that post. I cannot watch the video you've linked, but wanted to know what was your message. Have a good day. Link to comment Share on other sites More sharing options...
dimreepr Posted February 10, 2022 Share Posted February 10, 2022 8 minutes ago, Genady said: OK. I only wish you would make it clear in that post. If I could, I would... Link to comment Share on other sites More sharing options...
CharonY Posted February 11, 2022 Share Posted February 11, 2022 I wonder whether that is really a myth. Or conversely, are there studies that indicate that lionfish are non-disruptive for the ecosystems they got in? A quick google seems to indicate a fair number of studies where they seem to indicate significant damages. That being said, these were mostly a few years old already and it would be interesting to see what the current state of science is on that matter. One of the newer ones for example: https://doi.org/10.1080/03632415.2017.1340273 Quote Species invasions in marine ecosystems pose a threat to native fish communities and can disrupt the food webs that support valuable commercial and recreational fisheries. In the Gulf of Mexico, densities of invasive Indo-Pacific Lionfish, Pterois volitans and P. miles, are among the highest in their invaded range. In a workshop setting held over a 2-week period, we adapted an existing trophic dynamic model of the West Florida Shelf, located in the eastern Gulf of Mexico, to simulate the lionfish (both species) invasion and community effects over a range of harvest scenarios for both lionfish and native predators. Our results suggest small increases in lionfish harvest can reduce peak biomass by up to 25% and also that reduced harvest of native reef fish predators can lead to lower lionfish densities. This model can help managers identify target harvest and benefits of a lionfish fishery and inform the assessment and management of valuable reef fish fisheries. Link to comment Share on other sites More sharing options...
Genady Posted February 11, 2022 Author Share Posted February 11, 2022 The old studies were small, short, and not convincing. This newer study is 5 years old, and it still only claims that the lionfish "pose a threat" and "can disrupt." It doesn't show that it actually does. It is an assumption of the study and a justification for it. Plus, it is a simulation, in one locality, and only regarding effects of harvest on the lionfish population (on the assumption that we want to reduce it). What does it show? It shows that if we harvest lionfish more, then their numbers will decrease (hardly unexpected). And, if we harvest native predators less, then the lionfish numbers will decrease. The latter in fact shows that there are native predators of lionfish! What I see on the grounds here, in Southern Caribbean is, no long term effect, no observable damage to the reef ecology. That's why I suggest it is a myth. Link to comment Share on other sites More sharing options...
CharonY Posted February 11, 2022 Share Posted February 11, 2022 24 minutes ago, Genady said: What I see on the grounds here, in Southern Caribbean is, no long term effect, no observable damage to the reef ecology. That's why I suggest it is a myth. So is there data out there that would suggest either? Because most reports I can find on Lionfish does indicate that there are efforts underway to control them and I am unable to find reports indicating that they are mostly non-disruptive. Sure, it is possible that the worries were overblown, but before declaring it a myth, I would like to see some evidence. And if I scan lit on the Southern Caribbean I see a number of efforts to cull them (https://www.forbes.com/sites/daphneewingchow/2022/01/31/the-caribbean-is-taking-a-bite-out-of-its-invasive-lionfish-problem/?sh=648af9cb5e8f) There several papers that try to investigate the impact and cost of lionfish management, e.g. DOI:10.1007/s00227-015-2745-2 and a number of agencies, including NOAA seems to spend quite a bit of efforts on controlling this species, too: https://www.fisheries.noaa.gov/southeast/ecosystems/impacts-invasive-lionfish So at least that makes it strange that apparently either no one picked up on the fact that they are harmless (and spending a lot of money on it) or at least I cannot find reports on that. Link to comment Share on other sites More sharing options...
Genady Posted February 11, 2022 Author Share Posted February 11, 2022 I read these stories and I think they are just reprints from 10 and 20 years ago. All the same claims, perhaps in the same words. No new evidence, one way or another. Why people and organizations do what they do? I can come up with numerous reasons. I am sure, you can too. The most innocent being, better safe than sorry. I think it is difficult to show that something has no effect. It is usually a null hypothesis. Anyway, after some 30 years and the wide range of invasion, where is the damage? It supposed to be big. I cannot find reports on that. Link to comment Share on other sites More sharing options...
Genady Posted February 12, 2022 Author Share Posted February 12, 2022 In this picture, a lionfish and a sea urchin share a rock for food and shelter: Link to comment Share on other sites More sharing options...
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