Countdown to extinction: Saving the Last of the Maugean Skate

[@wildworld6264]

Thank you for making this video and shining a spotlight on the Maugean Skate. I see Australian Geographic called them the 'Thylacine of the Sea'. I hope we've learned our lesson from the Tasmanian Tiger and can prevent the Maugean Skate from going extinct.

[@drsammunroe]

Thanks so much for always watching and being so supportive!

[@grindingdeviance1864]

I never really thought about it before, but it makes sense that water without oxygen just causes a fish to drown, just as air with no oxygen would cause us to suffocate. Thanks for the video, Doctor. I always learn something from you. :)

[@drsammunroe]

Thanks so much!

[@jimmymartinez4534]

Son rayas realmente hermosas ❤

[@jordanmatthewstelck]

Dr. Sam! There's a new shark movie out called Under Paris! People are calling it a worthy successor of Jaws, and I agree. It explores how climate change is impacting sharks and their behavioral patterns. It's not as flashy as Meg or Deep Blue Sea, but I feel it delivers on realism, commentary, as well as suspense and scares. I believe you spoke about the sharks evolving behavioral patterns in one of your prior videos, so I think Under Paris might be right up your alley!

[@drsammunroe]

It is the next video on my list! I am super keen to review it. Thanks for watching and commenting!

[@jordanmatthewstelck]

@@drsammunroe There's a lot of juicy info and theories on evolution. I've watched it twice now, and the director even reposted some of my comments on instagram. I hope you're able to cover everything in it in a longer video 😋. It's quite an interesting film. 🤠

[@nicolafraser8348]

Thank you. This was really interesting, and I like the way you explained the situation in Macquarie Harbour. Are you able to tell me, please, when you recorded the interview with Dr Moreno? I ask because I'm wondering how his work is going with the captive-breeding. Are you thinking of providing an update when/if he has some baby skates?

[@drsammunroe]

Hi! So glad you enjoyed the video. I recorded the interview with Dr Moreno in December 2023. I am the slowest editor in history. But yes there is some news on the breeding program. Here is a video from ABC news with an update kzbin.info/www/bejne/l5e7lXangseUgtE

[@nicolafraser8348]

Thank you for the update

[@gulzamanwilliam3570]

Thanks for such a great information!!!!!!

[@drsammunroe]

You are so welcome!

[@Kelly-ky6yr]

There is no silver bullet and all threats need to be addressed, however, the Conservation Advice identified salmon farming operations as a “very high risk” threat that is “almost certain to impact the Maugean skate throughout the entire harbour” with “catastrophic” consequences. It advises to “eliminate or significantly reduce the impacts of salmonid aquaculture on dissolved oxygen concentrations” with the “fastest and simplest way” being the removal of salmon farming. We need to act to remove salmon farms -- yesterday!

[@erictaylor5462]

Assuming we had unlimited funds, could we pump air into the bottom of the harbor in the same was the pump in an aquarium works?

[@drsammunroe]

It's a great question and something that is currently being proposed. Check out this video by Salmon Tasmania on their proposed work to add oxygen back to harbour. kzbin.info/www/bejne/d6atdml9fp2sd6s. But do take it with a grain of salt because Salmon Tasmania is an industry body with their own agenda aimed at preserving the industry. They are not impartial. But it is a good summary of the mechanics for how such a project might work.

[@tosgem]

@@drsammunroe without consideration of a lot of variables, oxygenating the harbour could be dangerous for the species as well. Having too much oxygen, too often, in the wrong layers of water might open up the Maugean Skate to competition from other fish who normally would not survive there. Like misguided attempts to sink wells to provide water and greener spaces for threatened desert species, only to create an environment for common species from more temperate zones to come in and displace the desert species. The Maugean Skate's advantage, it's niche, is surviving particular conditions that seem to only exist in Macquarie Harbour (and formerly Bathurst Harbour, before the Maugean Skate went extinct there. Last specimen sighted there in 1992, environmental DNA samples indicate it's gone). Introducing too oxygen, in cycles that are too long might also increase possible metabolic rates of algae, increase rates of decomposition of organic matter in those lower layers of water which may have knock-on effects. It may be that the weather systems, storms, seasonal variations in river inflows create a system that the skates are adapted to navigate. Famine and feast cycles where they need the famine portion to, say, remove predators that prey on their young at certain times of the year. Who know what complex behaviours and rules they could be following: Move to X location, Y depth, when oxygen levels (or something else) increases in location Z. Spawn eggs in location A at depth B when C, D, E indicators tell them it's the right time. Do we know if the young make any journeys up the estuaries, a bit like salmon? And these if any of these paths have been disrupted? Maybe such paths go straight through some salmon farms, and when they follow it the salmon eat them!

[@1969utube]

It would be nice to think the salmon farmers are contributing to the cost of oxygenating strategies in the harbour, given they must accept some responsibility for the strain on the ecological imbalance their farms have brought about?

[@DanielStone-yw1rn]

I cannot believe they wreck the waterways is it so nothing flows