SEA BISCUITS: THEY REALLY DO CONTAIN DOVES – AND MORE!


Sea Biscuit Close-up, Abaco (Keith Salvesen)

SEA BISCUITS: THEY REALLY DO CONTAIN DOVES – AND MORE!

Recently I posed the question whether sea biscuits, like sand dollars contain ‘doves’. I had one in my hand, it rattled, I took a photograph through its ‘mouth hole’ and the question was answered. Biscuits do indeed contain doves – see HERE for details and comparisons with dollar doves.

Sea Biscuit 'Doves', Abaco (Keith Salvesen)

However, I spinelessly* failed to break open the biscuit to check out the contents more closely. I theorised that, because of the 5-way symmetry of these creatures, there would be 5 doves (which are in fact segmented mouth parts) in a biscuit exactly as with a dollar, and amiably challenged anyone to disprove it. [* biscuits and dollars are types of sea urchin – see what I did there?]

Dollar dove in close-up – one of 5 segmented mouth parts inside the ‘test’ (skeleton)Sand Dollar 'Doves', Abaco (Keith Salvesen)

Melissa Ann Guinness from Hope Town has a far more robust attitude to these things and, taking up the challenge, she heartlessly smashed open a sea biscuit from her collection to investigate further. I said I’d publish a correction if my theory was wrong. This is it – though in one arguable sense the theory holds good. It just didn’t go far enough…

Sea Biscuit 'Doves', Abaco (Melissa Ann Guinness)

In the above picture you can see (a) 4 quarters of a sea biscuit skeleton (b) 10 demi-doves (rather than 5 whole doves) and (c) a small mummified 5-limbed brittle star that was presumably in the creature’s digestive system when it died.

10 ‘demi-doves’  (or, when assembled, 5 doves that (unlike sand dollars) are in 2 parts
Sea Biscuit 'Doves', Abaco (Melissa Ann Guinness)

Complete doves

Sea Biscuit 'Doves', Abaco (Melissa Ann Guinness) Sea Biscuit 'Doves', Abaco (Melissa Ann Guinness) Sea Biscuit 'Doves', Abaco (Melissa Ann Guinness)

The final reconstruction – 5 doves and a bonus brittle star

Sea Biscuit 'Doves', Abaco (Keith Salvesen)

Photo Credits: Keith Salvesen (1, 2, 3, 10); Melissa Ann Guinness (4, 5, 6, ,7 ,8 ,9)

SEA BISCUITS: DO THEY REALLY CONTAIN DOVES?


Sea Biscuits, Delphi, Abaco (Clare Latimer)

Sea Biscuits on the Beach, Delphi, Abaco Bahamas

SEA BISCUITS: DO THEY REALLY CONTAIN DOVES?

A couple of years ago I wrote a post called ECHINODERMS, DOLLAR DOVES & PETRIFIED BISCUITS. It dealt with the… fact? rumour? old wive’s tale?… that within each sand dollar test (i.e. the white skeleton) are hidden 5 ‘doves’. You can hear them rattling inside if you shake the dollar… 

Sand Dollar Doves (Keith Salvesen) 6

Sand Dollar from Abaco containing 5 miniature white doves…

I investigated the theory with senior granddaughter, and we broke a sand dollar in half. And as you can see, the answer was undoubtedly yes – there were 5 tiny white doves, thus fulfilling the prediction of the famous ‘Sand Dollar’ poem that contains the lines  “Now break the centre open And here you will release The five white doves awaiting To spread good will and peace”.

Five white doves (in fact, the separated parts of the creature’s feeding apparatus)Sand Dollar Doves (Keith Salvesen) 1

A single dove, a picture of dovelinessSand Dollar Doves (Keith Salvesen) 3

I never thought to extend the experiment to sea biscuits, another object prized by beachcombers. All that changed last month when I picked up a sea biscuit and found that it, too, rattled.

A rattling good sea biscuit

So I turned it over to take a closer look at the underside. And there, unmistakably, was the source of the rattle – some kind of internal arrangement inside the feeding  hole (let us not pause overlong to consider the purpose of the other hole). But it wasn’t conclusively a dove.

So I shook it around a bit (sorry, doves) and zoomed in. And there was a small white columbine-type contraption remarkably similar to those found in the dollar dove. And no, I did not smash open the sea biscuit (it wasn’t actually mine). And no, I didn’t doubt any longer that sea biscuits also contain doves.

SO WILL THERE BE 5 DOVES, LIKE WITH THE DOLLARS?

I predict there will also be five. Both dollars and biscuits have ‘five-way symmetry’ (look on the topside of a biscuit or dollar to see how); and so the mouth (from which the ‘doves’ derive) will have a single part for each of the five sectors, all linked. 

If anyone would like to smash up one of their precious beach finds and test the theory, please feel free. Prove me wrong… and I’ll publish a correction! [Photo please…]

All photos Keith Salvesen except Header, Clare Latimer at Delphi

LEAST (BUT NOT LAST) SANDPIPERS ON ABACO


Least Sandpiper, Delphi Beach, Abaco (Charles Skinner)

LEAST (BUT NOT LAST) SANDPIPERS ON ABACO

There are 23 sandpiper species recorded for Abaco. Of those, 4 or 5 are vanishingly rare vagrants recorded once or twice in recent history (i.e. since about 1950).

Discounting those, the ones you are likely to encounter range from the large  (whimbrel, yellowlegs, dowitchers, stilts) to the small. Or, in the case of the least sandpiper, the least big of all. They are bigly little. Least Sandpiper, Delphi Beach, Abaco (Charles Skinner)

The binomial name of the least sandpiper – Calidris minutilla – is an apt clue to their size, the second part being Latin for “very small”. On Abaco, they are fairly common winter visitors, and each season a handful of them make their home on the beach at Delphi, where these photos were taken. Least Sandpiper, Delphi Beach, Abaco (Charles Skinner)

Along with their small sandpiper compadres such as SANDERLING, these busy, bustling birds of the shoreline are the ones known as “peeps” (also as stints). Least Sandpiper, Delphi Beach, Abaco (Charles Skinner)

Least Sandpipers breed in the northern tundra areas of North America. Like many or most shorebirds, newly hatched chicks are able to fend for themselves very quickly. It sounds unlikely I know, but within a couple of weeks or so they have fledged. Least Sandpiper, Delphi Beach, Abaco (Charles Skinner)

The birds forage on mudflats, in the tideline on beaches, and in wrack. They will probe into soft sand, sometimes the full length of their beak. They will even burrow right under weed to get at the concealed goodies. Their diet consists mainly of small crustaceans, insects, and snails.Least Sandpiper, Delphi Beach, Abaco (Keith Salvesen)

Credits: All photos by Charles Skinner (contributor to “The Birds of Abaco”) except the wrack-burrowers above, by Keith Salvesen (also on the Delphi Beach).

Least Sandpiper, Delphi Beach, Abaco (Charles Skinner)

WORLD SHOREBIRDS DAY, PIPING PLOVERS & IRMA


Piping Plover (Danny Sauvageau)

WORLD SHOREBIRDS DAY, PIPING PLOVERS & IRMA

Sept 6 2017. World Shorebirds Day dawns, even as the huge Cat 5 Hurricane Irma makes landfall over the small islands of the eastern Caribbean. Irma’s path has been relentlessly westwards, for sure – but the path has been unnervingly variable. The tracking reports showed Abaco successively as being in line for a direct hit; then taking a sideswipe from the south; then completely clear of the cone prediction; then within the northern edge… and today, a right hook to the east suggests again that Abaco will take a hit from irma (though as a predicted Cat 4 or maybe 3).

Hurricane Irma Tracking Path Sept 6th 2017 Wunderground

Far down the list of concerns in such a situation come shorebirds. Most if not all the islands that Irma will affect have wonderful shorebirds, both permanent and migratory. On Abaco my personal preoccupation is for the tiny Piping Plovers and our citizen scientist annual 6-month WATCH. Generally, the birds manage to find some cover at the back of the beaches to hunker down until the worst is past. But generally the beach populations are rather different after the storm, as birds scatter and take cover. 

Well, except this little guy who decided to take a windy bath on the Long Dock at Cherokee during Hurricane Matthew as it passed over Abaco last October (and props to Keith Kemp for braving the elements to get this shot!)

Birds are resilient and resourceful. Humans too. But nature unleashed with full force is a terrifying prospect. From a safe distance of 4250 miles from Marsh Harbour, thoughts and best wishes from Rolling Harbour will be with all those in the path of Irma over the next few days. 

Piping plovers on the Delphi Beach, at a more peaceful timePiping Plover, Delphi, Abaco (Keith Salvesen)

Photos: Danny Sauvageau, Keith Kemp, Keith Salvesen / Rolling Harbour; Graphic by Wunderground

WHY “ROLLING HARBOUR”? THIS MORNING’S VIEW…


Rolling Harbour, Abaco (Delphi Club Beach)Click to enlarge

SANDERLINGS ON ABACO: GOTTA LOVE ‘EM


sanderling-on-delphi-beach-abaco-keith-salvesen-7

SANDERLINGS ON ABACO: GOTTA LOVE ‘EM

Sanderlings. Wind them up with the concealed key under their left wing, and they will charge up and down the beach for an hour or two, pausing only to rip some small unsuspecting mollusk or crustacean from its sandy bed. These birds are tiny. And smart. They know all about how a retreating tide will expose the goodies. They are even happy to plunge their heads right under water (#2). They’re not really jumpy, if you don’t push your luck or have a dog with you. The best ploy of all is to find a flock near the tideline, choose a place to lie comfortably in dry sand (with a camera, I mean, otherwise you may look look a bit strange), and wait for them to come into range. Usually they are so busy, what with all that rushing around and feeding, that they will ignore you. So the hard part, after you have taken some photos, is catching the little so-and-sos to wind them up again…

sanderling-on-delphi-beach-abaco-keith-salvesen-1sanderling-on-delphi-beach-abaco-keith-salvesen-3sanderling-on-delphi-beach-abaco-keith-salvesen-2

VIDEO 1 In which we notice the scuttling and scooting around of sanderlings on a mission

sanderling-on-delphi-beach-abaco-keith-salvesen-4sanderling-on-delphi-beach-abaco-keith-salvesen-5sanderling-on-delphi-beach-abaco-keith-salvesen-6

VIDEO 2 In which we admire bathtime in a tide-pool and assorted comings & goings…

All photos and movies RH

“THE ADMIRABLE CHITON” (A DELPHI BEACH MYSTERY)


Fuzzy Chiton, Delphi, Abaco (Kasia Reid)

“THE ADMIRABLE CHITON” (A DELPHI BEACH MYSTERY)

The beach at Delphi is good for combing. Most of Abaco’s beaches are too, for that matter. You can find Kasia’s beachcombing page HERE. Last month 2 guests, Linda and Jan, went exploring on the beach and returned with a handful of mystery items they had found under the clumps of seaweed. These were clearly neither complete nor broken shells, and even after some research in books and online I remained baffled. They were obviously parts of some water-based species… but what parts, anatomically speaking? And what species?

Fuzzy Chiton valves (segments), Delphi Beach, Abaco, Bahamas

So I contacted Colin Redfern, Bahamian sea shell expert and author of a magisterial tome on the subject. His response was typically swift and definitive: 

The ladies have found some beach-worn valves from the common Fuzzy chiton, which was so nicely photographed by Kasia on your April 12, 2012 entry – (the one that included fecal pellets) [See Header]. As you know, the meat from this species is eaten by Bahamians, who discard the unwanted shell. The individual plates then become separated by wave action and normal deterioration. Abaco has a pretty good selection of chiton species, and individual valves from some of the other species are sometimes found on beaches.
Fuzzy Chiton, wiki

Chitons (pron. kytens) are marine molluscs with a great many species worldwide, from very small to quite large. Their shell comprises 8 interlocking and overlapping curved plates known as ‘valves’ that provide a flexible protection, and articulate as the creature moves. Chitons – at least some species – can even curl up into a protective ball. The plates are held together by a ‘girdle’ surrounding the animal.

Acanthopleura_granulata_(West_Indian_fuzzy_chitons)_(San_Salvador_Island,_Bahamas) James St. John

Fossil records show that these primitive-looking animals derive from the Devonian period – or even Ordovician. They remind me of trilobites, even older creatures from the Cambrian period that used to fascinate me at school when I was small and paying attention. The name chiton derives from Latin word for mollusc, which itself comes from an older Greek word meaning a tunic. Which they in no way resemble.

Fuzzy Chiton, Abaco (Kasia Reid)

After a chiton dies, the valves which make up the eight-part shell come apart because the girdle no longer holds them together and these the plates may wash up in beach drift, to be found by Linda and Jan. The individual shell plates are sometimes known as “butterfly shells” due to their shape.

A DOZEN CHITON FACT TO AMAZE YOUR FRIENDS WITH

  • Chitons are also known as ‘sea cradles’ or ‘coat-of-mail shells
  • Their shell consists of 8 plates / valves so flexible that they can even curl into a ball
  • They move with a muscular ‘foot’, and use it to cling onto rocks like a limpet
  • They have no definable head, no tail and no eyes, onlyphotoreceptor cell clusters’
  • The mouth on on the underside of the chiton
  • It contains a sort of tongue – a radula – with rows of teeth, each with 17 (why 17?)
  • They use the radula to scrape the rock substrate for algae and similar
  • A chiton’s digestive system produces neat little fecal packages like white pills
  • Its anus is next to its foot, a design mercifully not found in humans
  • I learn that chitons “lack a cerebral ganglion”. I think this means, no brain as such
  • However they do have a primitive ‘homing’ ability too complex to summarise…
  • Chitons are eaten by people mainly in the West Indies and the Philippines

Chiton, Abaco 2 (Kasia Reid)

WHAT? YOU CAN EAT THEM?**

If you are asking that question, you perhaps read right through the 12 facts to the very last one. If so, you deserve an answer and indeed a recipe for Chitons aka ‘Sea Cockroaches’. And who better to provide it than the brilliantly-named PSYKDELIASMITH Click the link to find out more.

**CAUTION As a couple of people have rightly pointed out (thanks Liann and Julias) since I posted this, not all chitons are edible. Some are poisonous. So before you think of a culinary chiton caper, best check that you have got an edible one

A chiton on the move, very slowly, and apparently halted by an encounter with a nerite

wp809b3177_06

Colin Redfern kindly sent me a pdf of the chiton section of his book. Of the fuzzy chiton he writes: “Occurrence: Very common intertidally on rocky shorelines. Known locally as a Curb, with the meaty foot used as an alternative to conch in salads. Gutted specimens or disarticulated valves consequently common along shorelines.” Which is just where this post began.

FUZZY CHITON scientific doc (Colin Redfern)

And if you want to know about the title and its link to Peter Pan, click THE ADMIRABLE CRICHTON

POST SCRIPT This post has generated quite a lot of comment on Facebook. Here are a few, plus an amazing discovery in Hope Town
  • “Commonly know as a curb, they are edible (raw) you make a salad like you do with conch , delicious !!!” (Rosalie Pyfrom)
  • True some are poisonous, but your have to know which ones!! I was showed as a child which were good from bad!!” (Janice Carey Hall) 
  •  “Very delicious” (Cantrell Walker)
  • “Lets not forget the poisonous ones!” (Julias Sawyer)
  •  “Don’t mess wit my curbs, nom nom”  + “Definitely do NOT eat the very large ones with the bumpy rim”.(Liann Key Kaighin)
  • “Curb stew is a Bahamian food that has since the loyalist arrived” (Steve Roessler)
 Gary Richardson Jr.'s photo.

Then Gary Richardson Jr added a photo of what must be a pearl, found in a curb in Hope Town. 

 To which I replied “Well that’s a surprise! Interesting find. Did a bit of research. Apparently all shelled molluscs are capable of producing ‘pearls’ – though they have no value. So this must be a chiton pearl…”
Credits: Linda & Jan for their beachcombing finds; Colin Redfern for his ID & info enabling this post (and his continuing interest); Kasia Reid; Hans Hillewaert & James St John (wiki uploads)