WHITE-TAILED TROPICBIRD: ABACO’S MOST ELEGANT BIRD


White-tailed Tropicbird, Abaco (Alex Hughes)

WHITE-TAILED TROPICBIRD: ABACO’S MOST ELEGANT BIRD

A competition to decide the most elegant bird found on Abaco (of 350+ recorded species) is a simpler task than it sounds. Colourfulness doesn’t come into (sorry, painted bunting, Abaco parrot & co). Nor cuteness, rarity, popularity and so on. Some birds don’t make the starting line at all (but we love you, ungainly limpkins and raucous clumsy-flying Anis). Best to judge from a different viewpoint: is there one bird that in flight is invariably beautiful to watch, in a way that can make you catch your breath…?

White-tailed Tropicbird, Abaco (Alex Hughes)White-tailed Tropicbird, Abaco (Alex Hughes)

The caribbean white-tailed tropicbird (Phaethon lepturus catesbyi) is one of six types of tropicbird found worldwide. It is named after pioneering naturalist MARK CATESBY, who predated John James Audubon. Click the link to find out more about him. Catesby’s depiction (below) of a ‘Phaeton’ must be one of the earliest.

Catesby’s TropicbirdTropicbird - Mark Catesby jpg

IMG_0413

In the Bahamas, tropicbirds are summer resident only and breed on the islands. Abaco is fortunate to have several breeding colonies, not all in remote or inaccessible places. Female tropicbirds lay a single egg directly onto the ground or on rocky ledges and in rocky holes. One might suppose that such limited egg production with a somewhat high-risk nesting policy, coupled with modern problems such as habitat destruction, might affect numbers. However, these fine birds seem to be doing well, and are IUCN-listed ‘Least Concern’.

This tropicbird on Abaco has found a safe place to nest in a rocky holeWhite-tailed Tropicbird on nest, Abaco (Alex Hughes)

Tropicbirds have a variety of local names in the Caribbean, for example ‘longtail’ and ‘bosun bird’ (after their screeching call). They plunge-dive for fish, but are inexpert swimmers. This is a factor I am prepared to overlook in the elegance contest. They were born to fly high, not to paddle about.

White-tailed Tropicbird, Abaco (Alex Hughes)White-tailed Tropicbird, Abaco (Alex Hughes)

THE STORY OF TB THE TROPICBIRD

A couple of years ago, a tropicbird chick was rescued by a dive boat and given to Melissa Maura, well-known for her animal magic, to care for. She nurtured ‘TB’, giving him a soft bed and providing him with a swimming pool. To begin with, it looked as though he might not be able to fly at all, but as he became stronger he started to flap his wings.

White-tailed Tropicbird, Bahamas (Melissa Maura)White-tailed Tropicbird, Bahamas (Melissa Maura)

Then it was time to go to the beach, get acquainted with sand and sea, and practise flying. I have some pathetic photos of an exhausted TB lying flat out on the sand after his initial attempts to fly. But Melissa and TB persevered with the flying practice and in due course TB began to get the hang of it. Finally, the great day arrived. Melissa and a friend took TB down to the beach and launched him into the air. He took off, flying strongly away, never to return. A moment of triumph mixed with poignance.

  White-tailed Tropicbird, Bahamas (Melissa Maura) White-tailed Tropicbird, Bahamas (Melissa Maura)White-tailed Tropicbird, Bahamas (Melissa Maura)

You are very welcome to propose a rival in the elegance stakes in the comment box!

Credits: Main photos Alex Hughes; TB images Melissa Maura

White-tailed Tropicbird, Abaco (Alex Hughes)

ECHINODERMS, DOLLAR DOVES & PETRIFIED BISCUITS


Sand Dollar Doves (Keith Salvesen) 6

Sand Dollar from Abaco containing 5 miniature white doves…

ECHINODERMS, DOLLAR DOVES & PETRIFIED BISCUITS

Echinoderms (Gr. ‘Hedgehog Skin’) comprise a large variety of sea creatures characterised (mostly) by radial symmetry, often five-way. For Abaconians, the most frequently encountered are starfish, sea urchins, sand dollars and sea biscuits. I am going to look at two particular aspects of dollars and biscuits, conscious that my illustrative photos of white objects were stupidly taken against a white background.

DOLLAR DOVES

I’m sure all Bahamians know or are aware of at least one version of the famous ‘Sand Dollar’ poem, in which the various characteristics of the test (the skeleton of the creature) are given religious significance. One verse of the poem may be puzzling: “Now break the centre open And here you will release The five white doves awaiting To spread good will and peace”.

Recently, Senior Granddaughter (10 this week) was looking at some Abaco sand dollars in her unfeasibly huge collection of shells. She picked one up, shook it and it rattled. She said a friend at school had told her that a rattling sand dollar has ‘doves’ inside it, and asked if we could break it open and see. I’ve learnt that it is useless to argue with her – she has the tenacity of a trial lawyer – so we did. This is what we found.

Sand Dollar with a spiky interior like a white cave with stalagmites and stalagtitesSand Dollar Doves (Keith Salvesen) 4

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

Two broken pieces showing where the doves are centrally locatedSand Dollar Doves (Keith Salvesen) 5

A single dove (best viewed the other way up for full-on doveliness)Sand Dollar Doves (Keith Salvesen) 3

The photo below, from Pinterest, shows the ‘mouth’ with its 5 dove-parts intact, an arrangement called ‘Aristotle’s Lantern’.

Sand Dollar : Aristotle's Lantern : Doves (Pinterest)

PETRIFIED BISCUITS

In common parlance ‘petrified’ is an extreme version of ‘terrified’. Literally, it means ‘turned to stone’ (L. Petrus, a rock). It is descriptive of a state of fossilisation, where an animal skeleton or dead wood or plant matter turns over aeons into stone. Undaunted by her Doves discovery, SG (a most inquisitive girl) also discovered a box containing random stones and fossils. She found these two items:

Fossilised sea biscuitsPetrified Sea Biscuit (Keith Salvesen) 1

A closer look at the pair of rocksPetrified Sea Biscuit (Keith Salvesen) 5 Petrified Sea Biscuit (Keith Salvesen) 4

The undersides of the fossils above – looking like stones but with some tell-tale small holesPetrified Sea Biscuit (Keith Salvesen) 2 Petrified Sea Biscuit (Keith Salvesen) 3

A close-up of the pale biscuitPetrified Sea Biscuit (Keith Salvesen) 6

Sea biscuits as everyone knows them, on the beach at Delphi – skeletons but not yet fossilsSea Biscuits, Delphi, Abaco (Clare Latimer) copy

A ‘modern’ sea biscuit in close-upSea Biscuit, Abaco (Rhonda Pearce) copy

FUN FACT

Florida has an unofficial but proposed State Fossil, the ‘Sea Biscuit (Eocene Age)’. I didn’t know it before, but it turns out that around 40 States have State Fossils. Whatever next? State Bacteria?

SO HOW OLD MIGHT A PETRIFIED BISCUIT BE?

The fossil biscuits I have looked at, from Florida to Madagascar, are said to come from three specific historic epochs – from the oldest, Jurassic (145m – 201m years ago),  to Eocene (34m – 56m) and Pleistocene (0.01m – 2.6m). 

HOW DOES THAT HELP ANYBODY? BE MORE PRECISE

By all means. Here is an excellent Geochart that gives an idea of the time span. A Jurassic sea biscuit would be more than 145m years old. So maybe the next plan should be to take the 2 petrified sea biscuits plus SG to a museum to see if we can get an idea of their age…geotimescale

All photos ‘in-house’ except the Delphi biscuits, Clare Latimer & the single biscuit Rhonda Pearce; Geochart to be credited asap, mislaid the source…

ROLLING HARBOUR, ABACO: LIFE’S A BEACH & THEN SOME…


Rolling Harbour Beach, Abaco1b

ROLLING HARBOUR, ABACO: LIFE’S A BEACH & THEN SOME…

Rolling Harbour (the geographical feature) is a gently curving one-mile white sand bay presided over by the Delphi Club, which sits on a 50 foot cliff behind the beach. There are rocks at either end, fish in the sea (including bonefish and, in the right conditions, permit), birds on the shore and shells on the sand. And that’s it… 

Rolling Harbour Beach, Abaco2bRolling Harbour Beach, Abaco3bRolling Harbour Beach, Abaco4bRolling Harbour Beach, Abaco5bRolling Harbour Beach, Abaco6bRolling Harbour Beach, Abaco7bRolling Harbour Beach, Abaco8b

And if anyone can explain the strange ribbed sky effect that seems to have appeared from nowhere when I posted these photos that I took last year (300dpi), then I’d be very grateful…

FLAMINGO TONGUE SNAILS: ALL YOU NEED TO KNOW


Cyphoma_gibbosum Clark Anderson - Aquaimages

FLAMINGO TONGUE SNAILS: ALL YOU NEED TO KNOW

I wrote about FLAMINGO TONGUE SNAILS Cyphoma gibbous more than two years ago. They have not changed noticeably since then but this site has – in scope, available material and audience. So I am revisiting these small marine gastropod molluscs, which are related to cowries. The live animal is brightly coloured and strikingly patterned, but that colour only exists in the ‘live’ parts – the ‘mantle’. The shell itself is usually pale and characterised by  a thick ridge round the middle. These snails live in the tropical waters of the Caribbean and the wider western Atlantic. Whether alive or dead, they are gratifyingly easy to identify.

FLAMINGO TONGUE SNAIL ON A PURPLE ROPE SPONGEFlamingo Tongue on purple rope sponge ©Melinda Riger @ GB Scuba copy

FEEDING ON A CORAL STEM

This snail is snacking on a coral stem, leaving a feeding track behind it. The structural shell ridge is clearly visible beneath the distinctively marked live tissue of these creatures.

Flamingo Tongue LASZLO ILYES Cyphoma_gibbosum_(living)_2

The flamingo tongue feeds by browsing on soft corals. Adult females attach eggs to coral which they have recently fed upon. About 10 days later, the larvae hatch. They eventually settle onto other gorgonian corals such as Sea Fans. Juveniles tend to live on the underside of coral branches, while adults are far more visible and mobile. Where the snail leaves a feeding scar, the corals can regrow the polyps, and therefore the snail’s feeding preference is generally not harmful to the coral.

Flamingo_Tongue_Snail_on_Soft_Coral_LASZLO ILYES

The principal purpose of the mantle of  tissue over the shell is as the creature’s breathing apparatus.  The tissue absorbs oxygen and releases carbon dioxide. As I have seen it described (unkindly?) “it’s basically their lungs, stretched out over their rather boring-looking shell”. 

Flamingo Tongue, Abaco (Char Albury)

This snail species, once common, is becoming rarer. The natural predators include Hogfish, Pufferfish and Spiny Lobsters, though the spotted mantle provides some defence by being rather unpalatable. Gorgonian corals contain natural toxins and instead of secreting these, the snail stores them. This supplements the defence provided by its APOSEMATIC COLORATION, the vivid colour and /or pattern warning sign to predators found in many species.

It comes as little surprise to learn that man is now considered to be the greatest menace to these little  creatures, and the reason for their significant decline in numbers. The threat comes from snorkelers and divers who mistakenly / ignorantly think that the colour of the mantle is the shell of the animal, collect up a whole bunch from the reef, and in due course are left with… “boring-looking shells” (see photos below). Don’t be a collector; be a protector…
Flamingo Tongue, Abaco (Char Albury)

These photos are of flamingo tongue shells from the Delphi Club Collection. Until I read the ‘boring-looking shell’ comment, I believed everyone thought they were rather lovely… I did, anyway. You decide!

Flamingo Tongue Snail Shell, Keith Salvesen AbacoFlamingo Tongue Snail Shell, Keith Salvesen AbacoFlamingo Tongue Snail Shell, Keith Salvesen Abaco

Finally, a couple of videos. The first is rather charmingly titled ‘FLAMINGO TONGUES DOING…. SOMETHING’. Any (printable but amusing) suggestions via the Comment box are welcome. The second punchily summarises this post in 30 seconds. Maybe that’s all that was needed!

Image Credits: Clark Anderson, Melinda Riger, Laszlo Ilyes, Charmaine Albury, RH

Doh! Reading through this after posting I can’t remove from my mind the likeness of Homer Simpson on the snail in Melinda’s photo (2). I had to  check it out and… it’s uncanny!

Homer Simpson Flamingo Tongue copy images

THE CONCH QUEST OF ABACO…


Conch ©Melinda Riger @G B Scuba

THE CONCH QUEST OF ABACO…

Conchs are gastropods. They are food. They are decoration (anyway, the shells are). For some, they are a living. And on Abaco they are everywhere – alive in the waters, and as shells scattered on  beaches or piled up outside restaurants. So the quest for conch is an easy one. There are fears of overfishing, however, and an active organisation The Bahamas National Conchservation Campaign exists to protect them. Another similar Bahamas organisation is Community Conch.conchs-at-sandy-point-1 We found a nice half-buried conch shell at Sandy Point. It was full of sand grains and tiny shells – mini gastropods and bivalves – that took some time to wash out of the spiralling internal structure. Here are some studies of the shell. IMG_2438IMG_2442IMG_2444IMG_2445IMG_2448IMG_5279IMG_5278 The damage to the shell above is the place where it has been bashed in to enable removal of the occupant. In order to do so, it is necessary to break the strong vacuum that would prevent extraction if you tried by the conventional route. Effectively the conch anchors itself to its shell and must be cut out. The best way to make the hole is with the spiral tip of another conch. This breaks the suction and enables you to prise out the occupant…

935327_499742893413409_191944192_n                                                               CC_logo2

Finally, you can usually rely on me to go off-piste. So here is a video of how to make a conch horn to annoy your friends and neighbours with…

[youtube https://www.youtube.com/watch?v=ebzN79oNTJg]

CHRISTMAS TREE WORMS: FESTIVE CREATURES OF THE CORAL REEF


File:Spirobrancheus giganteus.jpg

CHRISTMAS TREE WORMS Spirobranchus giganteus

“PROBABLY THE MOST CHEERILY FESTIVE WORMS IN THE WORLD…”
File:Christmas Tree worms.jpgChristmas Tree Worms ©Melinda Riger @ G B ScubaFile:Spirobranchus giganteus (assorted Christmas tree worms).jpgFile:Spirobranchus giganteus (Red and white christmas tree worm).jpgFile:Christmas tree worm (Spirobranchus giganteus).jpg      File:Reef0232.jpgFile:ChristmasTreeWorm-SpirobranchusGiganteus.jpgFile:Spirobranchus giganteus at Gili Lawa Laut.JPG

DCB Xmas Credits: Melinda Riger of Grand Bahama Scuba, Wiki-Reef & RH

QUEEN ANGELFISH: COLOURFUL CORAL ROYALTY: BAHAMAS REEF FISH (13)


Holacanthus ciliaris (Wiki)QUEEN ANGELFISH: COLOURFUL CORAL ROYALTY – BAHAMAS REEF FISH (13)

One of the earliest posts in the Bahamas Reef Fish series was about Queen Angelfish Holacanthus ciliaris, and you can see it HERE. I make no apology for returning with some more recent photos from Melinda Riger – these fish deserve plenty of attention for their wonderful bright presence that stands out even amongst the colourful corals of the reef.

This first image is remarkable for its clarity and composition. What, I wonder, is the fish saying to Melinda as she presses the camera button? All caption suggestions welcome…Queen Angelfish © Melinda Riger @ G B Scuba

Angelfish are quite happy  to swim round either way upQueen Angelfish (Juv) ©Melinda Riger @ GB ScubaQueen Angelfish (juv) ©Melinda Riger @ G B Scuba

The juvenile of the species, nosing around the coral for tasty morsels,  is equally colourfulQueen Angelfish (juv) Melinda Riger @ G B ScubaQueen Angelfish Melinda Riger @ G B Scuba