‘CUDAS: “WHAT BIG TEETH YOU’VE GOT…”


Barracuda - Melinda Riger / Grand Bahama Scuba

‘CUDAS: “WHAT BIG TEETH YOU’VE GOT…”

Or, if not exactly big then lethally lacerating. Their sharp fangs are all different sizes, which gives more of a mincing effect than a clean bite. Then there’s the underbite, involving more mincing. And the fact that the teeth are set at different angles. That’s a third mincing effect. Prey in those strong jaws? No chance. 

Three -way mincing machine. Avoid.Barracuda - Melinda Riger / Grand Bahama Scuba Barracuda - Melinda Riger / Grand Bahama Scuba

Teeth? Enough dentition already. It’s impossible not to admire these lean, mean eating machines as they glide around in their natural environment. The photos below are designed to redress the balance a bit. Sinister, yes. But mighty fine fish, without a doubt.

Barracuda - Melinda Riger / Grand Bahama ScubaBarracuda - Melinda Riger / Grand Bahama ScubaBarracuda - Melinda Riger / Grand Bahama ScubaBarracuda - Melinda Riger / Grand Bahama ScubaBarracuda - Melinda Riger / Grand Bahama Scuba

All photos: Melinda Riger, Grand Bahama Scuba, with thanks as ever for her terrific photos

WTF? (WHAT’S THAT FISH?) 13: THE ROUGHHEAD BLENNY


Roughhead Blenny - Melinda Riger / Grand Bahama Scuba

WTF? (WHAT’S THAT FISH?) 13: THE ROUGHHEAD BLENNY

The WTF? series has looked at a number of bizarre reef denizens, and this little fish is certainly that. For a start, its ‘correct’ name is Acanthemblemaria aspera, an excellent challenge for saying 10 times very quickly **. And the name blenny comes from the Greek word for ‘slime’, quite enough to make the poor creature a laughing-stock in the reef community.

Roughhead Blenny - Melinda Riger / Grand Bahama Scuba

There are in fact several hundred blenny species and subspecies around the world. The roughhead is one of the most commonly found in western Atlantic subtropical and tropical waters. These are burrowing creatures, and they find holes in the nooks and crannies of coral reefs – and indeed in the coral itself. Brain coral seems to be a preferred location. Mollusc shells are another. Or they may just bury themselves in the sea floor. 

Roughhead Blenny - Melinda Riger / Grand Bahama Scuba

The  ‘roughness’ of head refers to the whiskery appendages (cirri) on a blenny’s blunt bonce – slender tendril or hair-like filaments. The word cirri is the plural version of the wispy high altitude cirrus clouds that streak the sky. These tendrils are shown clearly in some of the photos here, despite the tiny size of the fish (± 1 inch). 

Roughhead Blenny - Melinda Riger / Grand Bahama Scuba

THESE GUYS LOOK A BIT PRIMITIVE, AM I RIGHT?

To be precise – as far as is possible – blennies can be dated back to the Paleocene Era (or is it an Epoch?). This spanned a period 66 to 56 million years ago – around the time of the formation of the Rolling Stones.

Roughhead Blenny - Melinda Riger / Grand Bahama Scuba

You can find out more about roughheads in this excellent eHow video I came across after I’d written this post, to which I should now add that there is considerable colour variation in this subspecies, as you may already have noticed…

** You can also try this with ‘Red Lorry Yellow Lorry’. Yes I know. Maddening, isn’t it. You can’t stop now you’ve started. Sorry…

Credits: all photo, Melinda Riger; video, eHow

OCTOPUSES: WORTH LEARNING TO SCUBA FOR?


Octopus - Melinda Riger, Grand Bahama Scuba

OCTOPUSES: WORTH LEARNING TO SCUBA FOR?

If I had to give a single reason for learning to scuba, watching an octopus would be very near the top of a long list. It’s never going to happen for me, of course – I have about 17 excuses lined up just in case anyone should ask me to try it. But still. One can dream…

Octopus - Melinda Riger, Grand Bahama Scuba

Meanwhile, I can luckily rely on an experienced professional to get the shots. Here are a few great octopus photos taken by Melinda Riger of Grand Bahama Scuba – perfect examples of an excellent reason for chucking aside the snorkel and doing something a bit more adventurous. Maybe…

Octopus - Melinda Riger, Grand Bahama Scuba

RELATED OCTOPUS POST

THE CORRECT PLURAL Learn 12 essential octopus facts plus the definitively correct plural of the word ‘octopus’ (out of 3 rival options). Please note that the possibilities do not include ‘octopodices’, which would be latin for ‘eight rumps’ (or ‘asses’, as you might say), if such weird creatures existed.

Octopus - Melinda Riger, Grand Bahama Scuba

 

REMEOctopus - Melinda Riger, Grand Bahama ScubaMBER – KEEP AN EYE OUT…

 

STARR-STUDDED MUSICAL DIGRESSION

Does Ringo still have it? Did he ever have it?

PREHENSILE TALES FROM THE REEF (3): SEAHORSING AROUND


Seahorse (Adam Rees / .Scuba Works)

PREHENSILE TALES FROM THE REEF (3): SEAHORSING AROUND

It’s Friday at last. It’s springtime. A spirit of benign goodwill is evident in the vicinity of Rolling Harbour. Seahorses are irresistible. Don’t even try to pretend they don’t make you smile. Hippocampophobia is an affliction that, as yet, has never been diagnosed in a human being – for whom fear of beards, clowns and the number 5 (quintaphobia) are known medical conditions. Immerse yourself with these little creatures – and then have a good weekend.

Seahorse (Adam Rees / Scuba Works)Seahorse (Adam Rees / Scuba Works)Seahorse (Adam Rees / Scuba Works)Seahorse (Adam Rees / Scuba Works)Seahorse (Adam Rees / Scuba Works)Seahorse (Adam Rees / Scuba Works)

All fantastic hippocampi photos: Adam Rees / Scuba Works

FORAYS WITH MORAYS (4): EXPRESSIVE FEATURES


Green Moray Eel (Melinda Riger / Grand Bahama Scuba)

FORAYS WITH MORAYS (4): EXPRESSIVE FEATURES

Time to return to those extremely expressive characters of the coral reefs, moray eels. Specifically, some green morays. One hesitates to anthropomorphise or ‘project’ human emotions onto creatures but with some species it’s hard not to do so. Following Mr Grumpy (or perhaps Mr Sad) in the header image, here are some close-ups of morays appearing to express their emotions, from happy to downright furious… Eels featured here include Judy and Wasabi, and I remind myself that the human habit of naming familiar wild creatures is itself a (perfectly harmless) form of benign animism. Exactly as with the regular banded piping plovers featured elsewhere in this blog that overwinter on Abaco’s beaches, such as Harry Potter, Bahama Mama and the delightfully-named Felicia Fancybottom…

Happy and contented?Green Moray Eel (Melinda Riger / Grand Bahama Scuba)Green Moray Eel (Melinda Riger / Grand Bahama Scuba)Green Moray Eel (Melinda Riger / Grand Bahama Scuba)

Something on my mind…Green Moray Eel (Melinda Riger / Grand Bahama Scuba)

Slightly amused?Green Moray Eel (Melinda Riger / Grand Bahama Scuba)

Pretty funny, actuallyGreen Moray Eel (Melinda Riger / Grand Bahama Scuba)

Ha ha…! Hilair!Green Moray Eel (Melinda Riger / Grand Bahama Scuba)

Watch it. You are beginning to bug us, Mr Harbour, with your stupid captionsGreen Moray Eel (Melinda Riger / Grand Bahama Scuba)

ANGRY. BACK OFF… NOW!!!Green Moray Eel (Melinda Riger / Grand Bahama Scuba)

THE NEXT POST WILL BE FROM ABACO HQ NEXT WEEK

Credits: All morayvellous photos, Melinda Riger / Grand Bahama Scuba except 6, Virginia Cooper / Grand Bahama Scuba

BLUEHEAD WRASSE: PRIVATE LIFE LAID BARE


bluehead_wrasse_thallasoma_bifasciatum_oregonstate-edu-pinterest

BLUEHEAD WRASSE: PRIVATE LIFE LAID BARE

The bluehead wrasse (or blue-headed wrasse) Thalassoma bifasciatum is a denizen of the coral reefs of the tropical waters of the western Atlantic Ocean. This bright little 4-inch fish is… a wrasse with a blue head. No more and no less. Unless it’s a juvenile. Then it is mainly bright yellow. It’s similar to BLUE TANG (aka ‘the Disney Dory’), which starts life bright yellow and grows up to be blue.

blue-head-wrasse-melinda-riger-g-b-scuba-copy

The species may be found singly, in pairs or small groups, or in schools.  They have an important role to play in the life of the reef. They are CLEANER FISH, vital to the health and wellbeing of the larger species they attend to, and thus of the reef itself. This is ‘cleaning symbiosis’, a relationship of mutual benefit. The big fish get cleaned; the little fish have a useful function and – importantly for them – therefore don’t get eaten. 

thalassoma_bifasciatum_bluehead_wrasse_san_salvador_island_bahamas-james-st-john-wiki

Having said that, blueheads are of course fair game as a snack for species that aren’t in the market for their cleaning services. And, unfairly, some species that are content to let cleaner gobies runtle around their gills and mouths are not so considerate of the wrasse. Some types of grouper and moray eel, for example.

bluehead_wrasse

TELL US EXACTLY SEVEN BLUEHEAD WRASSE FACTS

  • Juveniles can alter the intensity of their colour, stripes & bars
  • The bluehead wrasse is a ‘protogynous sequential hermaphrodite’
  • All are born female**. Some change sex to male during maturation (see below)
  • Food includes zooplankton, small molluscs and small crustaceans…
  • …and parasites / other juicy bits (fungal growths, anyone?) from bigger fish
  • The main threat to the species is coral reef degradation or destruction
  • The bright colours invite aquarium use, but the trade is not a significant one

** Some sources suggest some are born male and remain male. I’m not sure which is right

A juvenile bluehead (with feather-duster worms) – mostly yellow, with a pale underside
Bluehead Wrasse juvenile (wiki)

THE REMARKABLE SEX LIFE OF THE BLUEHEAD WRASSE

This is an unavoidable topic, I’m afraid. The bluehead’s sex life is the most interesting thing about them, and this is no time to be prudish. It is the subject of extensive scientific research, not all of which I have read since I decided to write about the species last night. Like many human relationships, “it’s complicated”, but in a conch shell it boils down to this:

  • To recap, BWs are born female and as they mature, some become male.
  • Males reach an ‘initial phase’ when they can breed in groups with females
  • Some males grow even larger & reach full colouration. This is the ‘terminal phase’
  • These large males aggressively chase away smaller ones & seek females to pair with
  • Their state of readiness (as it were) is signalled by colour changes
  • This behaviour is similar to that seen in many city centres in a Saturday night
  • The smaller fish have one bonus – their sperm count is higher than a dominant male
  • Prozac tests have shown that the drug reduces a dominant male’s aggression

blue-headed_wrasse_det (wiki)

As the excellent organisation OCEANA puts it: Bluehead Wrasses may reproduce in four different ways throughout their lifetime:  1) as a female in a group spawning event; 2) as a female in a pair spawning event within the territory of a large male; 3) as a small male in a group spawning event; and 4) as a dominant, terminal male in a pair spawning event within its own territory.

A cropped still from a video I took at Fowl Cay marine reserve. I’ve looked at dozens of images online and not found one that was all blue with a yellow end to its tail fin. Maybe it’s not a BW at all. Or it’s a different type of fish completely. Or perhaps it is just an all-blue alpha male.bluehead-wrasse-fowl-cay-mr-abaco

Credits & Sources: Melinda Riger; Adam Rees; James St John; Oregon State edu / Pinterest; Wiki images; self; Oceana; IUCN; magpie pickings

A bluehead wrasse passes the time of day with a gruntbluehead-wrasse-grunt-adam-rees

ABSORBING SPONGES ON THE BAHAMAS REEFS…


sponge-melinda-riger-gb-scuba

ABSORBING SPONGES ON THE BAHAMAS REEFS…

A while back I showed a collection of colourful sponges – one that you might come across with minimum equipment. Snorkel, mask, flippers. Oh, and a coral reef, if you happen to have one handy. I suspect that to quite a few people the word ‘sponge’ means soggy yellow thing, as found in the proximity of a bath. Or a scratchy nylon-based equivalent. Well, here are a few more sponges to enjoy. Some I can give you the names of, some I don’t know and am too idle busy to look up… Sorry.

sponges-melinda-riger-g-b-scuba

Candelabra Songe (with brittle stars attached)candelabra-sponge-melinda-riger-g-b-scubasponge-melinda-riger-g-b-scuba

Black Ball Spongesblack-ball-sponge-melinda-riger-g-b-scuba-copy

One for Valentine’s Dayheart-shaped-sponge-melinda-riger-gb-scuba

Vase Spongesvase-sponge- pink-melinda-riger-gb-scubavase-sponge-melinda-riger-g-b-scuba

sponges-and-coral-on-the-reef

Spawning Brown Encrusting Spongebrown-encrusting-sponge-spawning-melinda-riger-g-b-scuba

All photos: Melinda Riger, Grand Bahama Scuba