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Caulerpa now in BOI


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37 minutes ago, CarpeDiem said:

Apparently it is not toxic to humans in small doses according to tests done on rats (can't find the reference now).  However every publication says "do not eat"....

so a sushi empire is out of the question then.

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39 minutes ago, CarpeDiem said:

 

Apparently it is not toxic to humans in small doses according to tests done on rats (can't find the reference now).  However every publication says "do not eat"....

I never feel very happy or safe when I read statements like that. It is safe. for rats. and in small doses. Apparently it makes kina sterile...

Thanks for the links.

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21 minutes ago, harrytom said:

Very possible it came from the viaduct. Remember they dredge it and the dumpings were off cuvier island

So may of been here longer than we think.

Pretty sure that dumping ground was only approved at the end of 2022 and it got tied up in court battles.

That dumping ground also as far from the barrier as the Ports of Auckland are.

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Nothing new,Australia has had it since 2015 or been monorting it since 2015?

https://digital.library.adelaide.edu.au/dspace/handle/2440/104681

Populations of the green marine macroalgae Caulerpa taxifolia and Caulerpa cylindracea have invaded and spread throughout Mediterranean after they were introduced from Australia. In Australia, these tropical to subtropical species have established invasive populations in New South Wales, South Australia, and most recently, for C. cylindracea, in Victoria. Significant efforts have been made to elucidate the invasion history and geographic source locations of Mediterranean populations. The same effort has been lacking in Australia. Both species have provided challenges for molecular ecologists because of their predominantly clonal reproduction and low genetic variation within invasive populations in the case of C. taxifolia, and very high intra-individual genetic variation in C. cylindracea.

 

. I have also shown that the response of native and invasive Caulerpa spp. to climate change scenarios indicates that invasive populations of Caulerpa may become more abundant and continue to expand their invasive range in the future. I also identify the limitations of this body of work and the issues encountered in the program of research, and discuss future research possibilities for invasive Caulerpa species.

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Haha been here since 2021 but no action till 2022

https://niwa.co.nz/news/marine-invader-caulerpa-triggers-biosecurity-response

Two new species of non-indigenous algae were discovered in mid-2021, identified by NIWA researchers as Caulerpa brachypus and Caulerpa parvifolia

New Zealand has some native species of Caulerpa but the two species identified in 2021 showed similar characteristics to the highly invasive Caulerpa taxifolia that has been problematic overseas. Caulerpa taxifolia has been listed as a Notifiable Species under New Zealand’s Biosecurity Act since 2001. 

The two new species of Caulerpa were found in a variety of habitats and depths near Aotea. They covered large areas of seafloor and appeared to spread quickly.  

Both species were given the status of Unwanted Organisms under the Biosecurity Act in September 2021. 

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Umm the current dumping zone is just behind the Barrier near the old munitions dumping area -not way past Cuvier like what was done in the eighties and nineties, this is used by Pine Harbour , Westypark and others from around Auckland-which is of course why the Barrier residents and Iwi were so up in arms about it being granted permission.

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1 hour ago, waikiore said:

Umm the current dumping zone is just behind the Barrier near the old munitions dumping area -not way past Cuvier like what was done in the eighties and nineties, this is used by Pine Harbour , Westypark and others from around Auckland-which is of course why the Barrier residents and Iwi were so up in arms about it being granted permission.

Not according to the this document from POAL.

The Cuvier Dump Site ranges in depth from 500m to over 1200m and the seabed is likely to be primarily mud (60- 80%) and sand (20-40%), similar to the material being dumped. Since World War II the site has been used for the disposal of ammunition, decommissioned vessels, and dredged material from Auckland marinas. POAL used the Dump Site for the disposal of dredged material in the 1990s. Information on the ecology of the disposal area is limited because of its isolation and depth.

Capture.PNG.47e1f8ee7fc59200e48e2b4ecda142ae.PNG

 

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3 hours ago, waikiore said:

Umm the current dumping zone is just behind the Barrier near the old munitions dumping area -not way past Cuvier like what was done in the eighties and nineties, this is used by Pine Harbour , Westypark and others from around Auckland-which is of course why the Barrier residents and Iwi were so up in arms about it being granted permission.

Yes that why I emailed Eugenie Sage,she was Minister at the time for eviroment?Got a wishy washy reply as I said with fan worm being in Auckland and dumping so close to barrier,wont be long before fan worm is established.

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6 hours ago, Ex Machina said:

 Anywhere could’ve been the vector not just Auckland . If for example if it was off an anchor the boat could’ve have been heading north , stopped at mercs first then Barrier . That puts every harbour and domesticated inlet south and inshore of the mercs in the realm of possibility 

I believe the fanworm first was found in Lyttleton harbour, long befor it was discovered in Auckland.

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12 hours ago, CarpeDiem said:

Your question suggests that it has?

It sinks and it doesn't survive at depth. The world's currents take around 500years to do a full circle of the planet so it's had 23 million years to get to our coast.  In that time it hasn't made it across vast distances. 

New Zealand isn't special in this regard, it also hasn't made it (naturally) to West or East Coast of the Americas which are a sh*t load longer than NZs coast.  As we've read in this thread it also hasn't made it naturally into the Med. 

I suspect that the warm surface currents of the tropics only carry it so far before it gets pushed to depths that it cannot survive and turns back into ocean nutrients.

Sorry. Let me be clear. Having arrived somewhere, how did it spread.

Yes modern international shipping means things get moved to new areas across what were natural boundaries..

But once established the new organism will spread to every available niche, and the methods for this spread existed long before humans and boats. 

I thought it was this "secondary " spreading we were discussing.

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39 minutes ago, Black Panther said:

Sorry. Let me be clear. Having arrived somewhere, how did it spread.

Yes modern international shipping means things get moved to new areas across what were natural boundaries..

But once established the new organism will spread to every available niche, and the methods for this spread existed long before humans and boats. 

I thought it was this "secondary " spreading we were discussing.

Both conversations seem to be taking place simultaneously  ;-)

Once introduced it can move on coastal currents.

According to MPI, their theory is, that as it can't survive below 40m and it sinks, it's very unlikely to spread to the rest of the gulf on it's own.

I have not read any reason for why they reached that conclusion.

I guess we wait and see cause there is nothing else to do :-)

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Bit of a contradiction there by MPI, if it can drift on currents then currents may take it to Coromandel and beyond surely. How did it get to Barrier, if it was via yacht then we would expect have some sightings at one of of the popular mooring areas.

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37 minutes ago, Psyche said:

Bit of a contradiction there by MPI, if it can drift on currents then currents may take it to Coromandel and beyond surely. How did it get to Barrier, if it was via yacht then we would expect have some sightings at one of of the popular mooring areas.

Bland Bay isn't the most popular anchorage, yet it appears to be the epicentre of the outbreak. That just doesn't make sense, given MPI's argument that it is / has / can be spread by anchors.

I would argue it is far more logical that it got to Bland Bay by some other means, and that there is a risk that anchors could spread it around the rest of the Gulf.

The other thing that confuses me substantially (which isn't hard). How can it be in Tryphena, Bland Bay and Whangaparapara but not in Bowling Alley Bay or Fitzroy itself?

To almost answer my own question, we all know the East Auckland current sets southwards, and low and behold, dead down current, it has been found at Gt Merc.

That, and this whole argument that it sinks, so can't be spread by currents doesn't sound fullproof. All it needs to do is grow on a log, mussel bouy or any other piece of floatsome that washed into the Gulf in any one of the several major rain / flood events, and the caulerpa can be hitching a ride to any bay it wants. Include Rawhiti.

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48 minutes ago, K4309 said:

That, and this whole argument that it sinks, so can't be spread by currents doesn't sound fullproof. 

If your theory is right, then it should be found all the way down the eastern coast as far as the Chatham rise.

PS: Blind, not Bland ;-)

 

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12 hours ago, CarpeDiem said:

PS: Blind, not Bland ;-)

 

Argh, I thought it was Blind Bay and changed it worrying someone would correct me...

Where is Bland Bay then? On the eastern side of Whangamumu (or the other Whanga-harbour, the one just north of Elizabeth Reef and Rimariki Island?)

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Here is a question:

The good folk of the Barrier are known to be strongly independent. Some would say they are likely to have a deeper distrust of the government than most of us.

Noting it was an outsider that first reported the infestation in Blind Bay, the first thing MPI did was stop all the locals from fishing. Giving there is bugger all else to do on the barrier, and there isn't a Countdown, that can be a bit of a problem. After several hui MPI have let them fish in their own bays again with a bunch of rules. Effectively meaning they can only fish out of kayaks.

Knowing that MPI can't actually fix or remove the caulerpa, and that the most likely immediate outcome is they can't go fishing, do you think the Barrier locals would actually report more caulerpa if they saw it?

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