new info – Pumice flotsam attracts settlers

Additional pumice information – see “comments” below – thanks Chris…..

There has been a lot of pumice washed up along the tide line this year, from tiny pieces to quite large lumps. Often the pumice will have been at sea for long periods and its gritty surface is an ideal landing place for many small floating animals and plants.

This specimens has attracted Goose Barnacles  – and goose barnacles ON goose barnacles, two other sorts of barnacle and what looks like some kind of marine worm.

Thanks to Chris Nicholls for the photo

Pumice flotsam with attachments Photo    Chris Nicholls

Pumice flotsam with attachments
Photo Chris Nicholls

Peter Fullagar – scientist working now in his 54th consecutive year of shearwater studies on Montague Island – has mentioned that on performing post mortems on dead young shearwaters, they have often found this year that the birds’ stomachs are full of pumice lumps instead of the more usual plastic debris. Pumice is a natural substance , but equally indigestible to baby seabirds. Apparently the adults can eject non-digestible morsels, but juveniles can’t.


2 replies
  1. Libby Hepburn
    Libby Hepburn says:

    Dear Atlanats,
    Chris has sent me this email chain with further very interesting information about the rash of pumice and its attendant passenegers, so I thought I would pass it on. Please read from the bottom upwards, cheers, Libby

    Hi Libby,

    Relating to that previous conversation via email – about the pumice washed up on our beaches…. A very interesting conversation worth sharing with you and the Atlas of Life folks if they are interested.

    Start from the bottom and read up the chain.


    From: Scott Bryan
    Date: 3 January 2014 8:46 am
    To: Christopher Nicholls
    CC: David Nicholls , Jason Evans
    Subject: More pumice
    Hi Chris and David,
    Thanks for the photo. Yes, very familiar. There are anemones on it, and the black bristle worms, which we have seen preparing on the barnacles. Amazingly, for a motile species, they never hop off the pumice once washed up on the beach and die with everything else. The crab species was probably Planes sp. A common drifter on floating objects. The anemones are Calliactus sp, which we have also seen detach and move around in tank conditions.


    Sent from my iPad

    On 3 Jan 2014, at 6:35 am, “Christopher Nicholls” wrote:



    Thanks Scott for your very detailed response.

    I took the picture above of a large lump of pumice pretty much as you described it – it even had a little crab attached. Along with just about everything you noted!

    I found this freshly washed up on Merimbula main beach early in December.



    Christopher A. Nicholls

    M: +61(0)418 487322
    P: +61 (0)2 6495 1093

    On 2 Jan 2014, at 11:35 pm, David Nicholls > wrote:

    Thanks, Scott, that was a excellently detailed answer! Exactly what I was hoping for. The wildlife attached to the pumice lumps is as you described (my brother Christopher has photographed it, hence the cc.).

    Again, thanks, much appreciated.


    Research School of Astronomy & Astrophysics
    Mt Stromlo Observatory
    Australian National University

    On 02/01/2014, at 11:06 PM, Scott Bryan > wrote:

    Dear David and Jason,

    Thanks for your emails. The pumice is from the Havre seamount that erupted on July 18 in 2012. It was a pretty big submarine explosive eruption, punching thru 700 m of water to breach the surface and producing a pumice raft >20,000 km^2, equivalent to size of Belgium. Amazingly. No one knew of the eruption for 2-3 weeks after when a tourist spotted the raft from a commercial flight. Havre is about 1000 km north of Auckland in the Kermadecs. The pumice is fairly white to light grey when fresh/broken, and differs from the Tongan pumice Jason and I studied previously which is a much darker grey. This pumice is also distinctive for its size – football-sized pieces have washed up here.

    The pumice has been washing up along our coast since late March. I was down that way (Ulladulla and Eden) back in late October and pumice was on the beach then, and had been there for a couple/few weeks. Also lots of dead shearwaters too. We have been having lots of new strandings the last couple of weeks here at the Gold Coast/southeast Queensland. The pumice is well-fouled, usually covered in Cyanobacteria (dark black/green skin), Bryozoa, goose barnacles, anemones, bristle worms, serpulids, hydroids, calcareous algae, molluscs, starting to see some corals attached, and other motile animals like crabs, Gastropoda attached.
    The pumice is well-travelled, reaching Tonga, Fiji, NZ, and all along east coast of Australia from Torres Strait to Eden, and probably a bit further south along the Vic Coast. Hope Jason can get our trajectory model working to show the likely paths of the pumice here 🙂

    Hope that helps. Expect to see minor strandings and new arrivals for the next few months when we have big tides and strong onshore winds.


    PS we have released quite a few media releases and some images of it via GBRMPA and QUT.

    Sent from my iPad

    On 2 Jan 2014, at 5:24 pm, “Jason Evans” > wrote:


    Any ideas for David?


    ——– Original Message ——–
    Subject: More pumice
    Date: Thu, 2 Jan 2014 07:20:39 +0000
    From: David Nicholls >
    To: >

    Hi Jason,

    I’ve been down at Merimbula (NSW) for a few days and noticed quite a lot of pumice at the high tide mark along several of the beaches. Doing a quick google-bash I found your 2004 paper from Earth & Planetary Science Letters, so I thought I’d ask if you know the origin of this latest pumice stranding?

    It looks like the pumice has been at sea for quite a while, as some of the larger pieces have shellfish and what look like barnacles attached. There is quite a range of sizes in the pumice, from 5mm and less up to >12 cm diameter.


    David Nicholls
    Research School of Astronomy & Astrophysics
    Mt Stromlo Observatory
    Australian National University


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