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JACKKNIFE FISH: BAHAMAS REEF FISH (30)


Jackknife Fish ©Melinda Riger @ GB Scuba

JACKKNIFE FISH: BAHAMAS REEF FISH 30

The rather uncomfortably ‘double-k’  Jackknife fish is one of 3 types of similar drumfish subspecies of Equetus found in Bahamas waters. The others are the High Hat and the SPOTTED DRUMFISH – the first fish featured in this series. Each of these drumfish species has juveniles that are elegant and delicate, becoming more conventionally fishlike as they grow to adulthood, as the final image shows.

Jackknife fish (juv) ©Melinda Riger @ G B Scuba copy

I always want to stick a hyphen in to separate each k: jack-knife fish. I think it’s an English thing. I have seen, at the other extreme, ‘jack-knifefish’, which looks most weird of all. Checking online, jackknife fish wins by a distance as the correct spelling. 

Jackknife Fish (juv) ©Melinda Riger @GB Scuba

These little fish, typically between 6 and 9 inches, inhabit the coral reefs of the Caribbean, the Gulf of Mexico, Florida and the Bahamas. Juveniles eat plankton and similar organism, graduating to small crabs and shrimps as adults.

Jackknife Fish ©Melinda Riger @ G B Scuba

A FULLY GROWN JACKKNIFE FISH (NOAA)Jackknife fish adult_NOAA_Photo_Library

Like other drumfishes, the jackknife can produce ‘croaking’ or ‘drumming sounds. This involves the fish beating its abdominal muscles against its swim bladder. There’s a lot more to it than my rather simplistic summary, but it’s probably as much as anyone needs or wants to know… The primary reason is believed to relate to mating. Other reasons include ‘low-level aggression’, and keeping in touch with each other in turbid waters.  I prefer the unscientific theory that sheer happiness makes them croak. Here’s a short video of a happy juvenile Jack knife fish (that’s yet another spelling variant…)

RELATED POSTS

Credits: Melinda Riger / GrandBahama Scuba; NOAA

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WTF? (WHAT’S THAT FISH) (10): FLYING GURNARD


Flying Gurnard (Adam Rees / Scuba Works)

WTF? (WHAT’S THAT FISH) 10: FLYING GURNARD

Imagine that you are swimming along resplendent in your snorkelling gear (me) – or in scuba gear for the advanced swimmer (you). There, below you, camouflaged against the sea bottom is a fish. A strange-shaped brown sort of creature with odd side fins. As it progresses over the gravelly sand, your immediate reaction is ‘what the…?’ Its fins seem to be turning into… wings. Like this:

Flying Gurnard (Adam Rees / Scuba Works)Flying Gurnard (Adam Rees / Scuba Works)Flying Gurnard (Adam Rees / Scuba Works)

Yes, it’s a flying gurnard. Unlike flying fish, it can’t actually fly through the air. But once its wings are fully spread, it certainly looks as though it could.

Flying Gurnard (Adam Rees / Scuba Works)Flying Gurnard (Adam Rees / Scuba Works)

WHAT’S THE POINT OF THE WINGS IF THE THING CAN’T FLY?

This gurnard species usually gets around using its ventral fins as ‘legs’, with the pectoral fins (‘wings’) close to the body. There seem to be several possible reasons for possessing the ‘sudden-deployment-of-flashy-wings’ superpower. 

  • It surprises and deters predators by movement, turning prospective prey into an apparently different creature
  • Bright or lurid colouring may be a deterrent warning of a foul-tasting or poisonous species  (APOSEMATISM)
  • A creature may actually be harmless and even tasty (as here) but may appear to be unpalateable or poisonous (BATESIAN MIMICRY)
  • In any event, the wings enable the fish to take off from the sea bottom and travel faster by ‘flying’ thought the water to escape a predator

Dactylopterus_volitans Flying Gurnard (cralize wiki)

I had a quick look to see how  scientists in history had depicted this extraordinary fish. The earliest illustration I could find was taken from “Allgemeine Naturgeschichte der Fische (General natural history of fishes),” a 12-volume encyclopedia by author/illustrator Marcus Elieser Bloch (1723-1799), which described all fish species then known to science (and 267 previously unknown) (© AMNH\D. Finnin) sourced from ‘Hyperallergic’
Flying Gurnard

Here’s a short video of a flying gurnard on the move, from ‘Sia Big Fish’

Credits: All main images Adam Rees / Scuba Works with many thanks, except final one ‘cralize wiki’; Hyperallergic for the historic image; Sia Big Fish for the video

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WTF? (WHAT’S THAT FISH) (9): THE HARLEQUIN BASS


Harlequin Bass ©Melinda Riger @ G B Scuba copy

WTF? (WHAT’S THAT FISH) (9): THE HARLEQUIN BASS

I’m conscious of being rather unfair on this pretty dwarf bass species by including it in the WTF? series. The usual denizen of the series is a fish so strange that one’s immediate instinct is to yell into one’s facemask, “WTF?”. BATFISH or FROGFISH or GUITARFISH and their bizarre ilk. So with apologies to this species for its somewhat harsh classification, here are some quite flattering photos of it to make up for any hurt feelings.

Harlequin Bass Fish ©Melinda Riger @ G B Scuba copyHarlequin Bass (jpc what'sthatfish)

The Harlequin Bass Serranus tigrinus has unusually striking body markings and a rather endearing spotty tailfin. They are hardy creatures and I note that they are recommended aquarium fish “and make a great candidate for beginners”, though there are warnings that they are “semi-aggressive”. NB they are only a few inches long, so no need to panic.

Harlequin_Bass_Serranus_tigrinus wikiHarlequin_Bass_(Serranus_tigrinus) wiki

If you are still not confident that you can ID one in the wild, here is a short video… Actually I’m really including it to show how these fish swim around. And next time, I promise a truly eye-watering WTF? fish from Bahamian waters, though its camouflage is so good that you may never notice it…

Credits: Melinda Riger / Grand Bahama Scuba (1, 2); jpc/ what’s that fish; wiki

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REMARKABLE REEF CREATURES TO ADMIRE


Octopus (Adam Rees : Scuba Works)

REMARKABLE REEF CREATURES TO ADMIRE

Here is a small collection of recent photographs from Adam Rees of Scuba Works. Three OCTOPUSES, an astounding FROGFISH,  a SEAHORSE, a MANTIS SHRIMP at close quarters, and a wonderful HAWKSBILL TURTLE. Clicking on a link will take you to a post with more photos and information about each creature. If these images don’t make you want to scuba then… what will?

Frogfish Hunting (Adam Rees : Scuba Works)Seahorse (Adam Rees : Scuba Works)Mantis Shrimp (Adam Rees : Scuba Works)Octopus 3 (Adam Rees : Scuba Works)Hawksbill Turtle (Adam Rees : Scuba Works)Octopus 2 (Adam Rees : Scuba Works)

All photos Adam Rees / Scuba Works, with thanks for use permission

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WTF? (WHAT’S THAT FISH) (7): THE SOAPFISH


Soapfish ©Melinda Riger @ GB Scuba

WTF? (WHAT’S THAT FISH) (7): THE SOAPFISH 

The WTF? series features some of the stranger fish that inhabit the waters of the Bahamas. Ones that, were you to encounter one on the reef, might make you exclaim “WTF?”. The soapfish Rypticus belongs in the same family as grouper and sea bass. Within the soapfish genus there are quite a few varieties in different shapes, sizes and colours that include several mottled, freckled, spotted and generally blotchy fish.  This post features one (or two) of them! Sorry to be lame here and lacking in authority, but having looked carefully online at images of several types of soapfish, I reckon there are 3 candidates. Freckled, I think these are. Enlightenment would be welcome!

Soapfish ©Melinda Riger @ G B Scuba

Rypticus tend to inhabit shallower tropical and sub-tropical waters. They are mainly nocturnal in their habits, feeding at night on small fish, crustaceans and molluscs. The WTF? factor arises from the creature’s oddly truncated shape. If you cover the back end of the fish in the image below with your hand, you might expect the fish to be about the same length again. But no, there’s just the tail to come. It looks a bit cut in half.

Soapfish © Melinda Riger @GB Scuba

DOES THE SOAPFISH HAVE ANY AWESOME POWERS?

I’m glad you asked because in fact it has two. First, these fish respond to threats by secreting large amounts of toxic mucus from their skins. This acts as a defensive barrier to repel predators. Secondly, female soapfish are able to change sex to male. This is not uncommon among fish, and in some (e.g. Clownfish) the change works the other way, male to female. I read a lot about chemicals and gonads in this connection, then decided to spare you the details. So basically, it’s toxic slimy coats and female gender realignment.

Soapfish ©Melinda Riger @ Grand Bahama Scuba

Credits: all photos, Melinda Riger of Grand Bahama Scuba

 

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“CLEANING UP”: HOW TINY REEF FISH HELP LARGE FISH


Black Grouper - Arnold - Cleaning Station - Neon Gobies ©Melinda Riger @ G B Scuba copy

“CLEANING UP”: HOW TINY REEF FISH HELP LARGE FISH

A while ago now, I wrote a detailed post about so-called fish ‘cleaning stations’ – the special spots on the reef where large fish can go to have small fish buff up their scales and floss their teeth. You can read all about it HERE.

I have accumulated a number of new photos from expert scuba diver and underwater photographer Melinda Riger that demonstrate this phenomenon. A big fish with a normally voracious appetite will patiently wait while gobies and other small fry go about their work. This often involves actually entering the mouth of the (as it must seem to them) monster to pick the insides and the teeth clean. There is an extraordinary understanding and trust between the species that means during the operation, the little fish are perfectly safe. Here are some examples, of which the very recent header image of a grouper named Arnold is quite outstanding.

Tiger Grouper + cleaner goby ©Melinda Riger @ G B Scuba copyGrouper, Black at cleaning station ©Melinda Riger @G B Scuba copy Tiger Grouper at cleaning station ©Melinda Riger @ G B Scuba copy Tiger Grouper being cleaned ©Melinda Riger @G B Scuba copy

It is not just gobies that attend the fish. Various species of shrimp also volunteer for the job.

Tiger Grouper with cleaning shrimps and goby ©Melinda Riger @ G B Scuba copy Grouper being cleaned ©Melinda Riger @ GB Scuba copy

Groupers are not the only species to make use of cleaning stations. Here is a dog snapper at the same cleaning station as the grouper in the header image. Below is a stingray being attended to.

Dog Snapper at cleaning station ©Melinda Riger @ G B Scuba copy

Southern Stingray with cleaning gobiesStingray, Southern with cleaning gobies ©Melinda Riger @ G B Scuba copy

GRAMMATICAL DIGRESSION There is this ‘thing’ about the correct use of the words ‘fish’ and ‘fishes’ in the plural form. The basic principle is simple: ‘fish’ where you are referring to several of the same species; ‘fishes’ where more than one species is involved. I don’t care. My policy is to use ‘fish’ as the plural on all occasions, so I don’t have to think about it. Pedants, look away now.

RELATED POSTS

TAKEN TO THE CLEANERS

BANDED CORAL (‘CLEANER’) SHRIMP

TIGER GROUPER

BLACK GROUPER

All photos: Melinda Riger, Grand Bahama Scuba

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“CALLING ELVIS” (THE SQUIRRELFISH, NOT THE MAN)


Squirrelfish Elvis ©Melinda Riger @ G B Scuba

“CALLING ELVIS” (THE SQUIRRELFISH, NOT THE MAN)

How proud The King would be to know that his name lives on in the form of an attractive though sadly unmusical Bahamian squirrelfish. This little guy is at least 5 years old. What is more, he has lived at the same address all that time, defending it against usurpers and protecting himself from predators in its safe depths. Here is the loveable little Elvis photographed at home between 2012 and 2016 (header image), the master of his own underwater Graceland…

Squirrelfish (%22Elvis%22) ©Melinda Riger GB ScubaElvis the Squirrelfish ©Melinda Riger GB Scuba Squirrelfish ©Melinda Riger @ GB Scuba Squirrelfish ©Melinda Riger @ G B Scuba

The reason that Elvis has such large eyes is that these fish are mostly nocturnal, and (apart from when Melinda is out with her camera), he and his friends spend most of the day either at home, or in crevices, small rock caves, or under ledges. However, here are a couple of shots of Elvis out and about, enjoying some quality time among the corals.

Squirrelfish (Elvis) ©Melinda Riger @ Grand Bahama ScubaSquirrel Fish ©Melinda Riger @ G B Scuba

ROLLING HARBOUR MUSICAL DIGRESSION

I so wanted to add a specific Elvis catalogue ‘Musical Digression’, but try as I might, there is no title in The King’s discography that has any potential for finny nuance or piscine pun value. However, here’s a track from the now tragically unhip Dire Straits on their follow-up album to the phenomenal ‘Brothers-in-Arms’, the much under-rated ‘On Every Street’. I give you… Calling Elvis, a song that cunningly contains as many titles of Presley hits as anyone could ever wish for.

All images: Melinda Riger at Grand Bahama Scuba; cartoon from a sequence on the excellent BCCR Defenses page – learn about camouflage and other fishy self-protection techniques

Nocturnal squirrelfish checks out a parrotfish’s sleeping arrangementscamoSquirrWparrot01

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BLUE CHROMIS: BAHAMAS REEF FISH (29)


Blue Chromis & Coral ©Melinda Riger @ GB Scuba

BLUE CHROMIS: BAHAMAS REEF FISH (29)

The little blue chromis Chromis cyanea will be instantly familiar to any snorkeler or scuba diver on the coral reefs of the Bahamas. These ever-present small fish – 6 inches long at most – are remarkable for their iridescent deep blue colour that flashes as they dart in and out of the coral and anemones of the reef.

Blue Chromis ©Melinda Riger @ G B Scuba

Although at first sight  this chromis species – one of many – looks blue all over, adults have a black dorsal stripe and black edging to their fins. They make colourful additions to aquariums, though to my mind they look far more attractive nosing about the reefs foraging for the zooplankton upon which they feed (see header image for details…)

Blue Chromis ©Melinda Riger @ GB Scuba

The blue chromis was the second fish species I encountered on my first ever reef dive, at Fowl Cay Marine Preserve with Kay Politano. The first fish was the endearingly inquisitive sergeant major with its smart black and yellow stripes which came right up to my googles to eyeball me. I loved that, even though my pitiful swimming technique meant that I had plenty of other distractions, not least remembering to breathe. Air, that is, rather than water.

Blue Chromis ©Melinda Riger @ GB Scuba

Chromis_cyanea_(blue_chromis)_(San_Salvador_Island,_Bahamas)

SO JUST HOW BIG ARE THESE FISH, COMPARED, SAY, TO A BLUE TANG?

Blue Tang with blue chromis in its wakeBlue Tang with Blue Chromis © Melinda Riger @GB Scuba copy

All photos Melinda Riger of Grand Bahama Scube, except the penultimate by James St John, taken in San Salvador

 

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WTF? (WHAT’S THAT FISH) (6): THE SAND DIVER


Sand Divers Bahamas ©Melinda Riger @ G B Scuba

WTF? (WHAT’S THAT FISH) (6): THE SAND DIVER

Time for another in the WTF? series, featuring weird (begging their pardons) or not very fish-like fish. The Sand Diver Synodus intermedius is a type of lizardfish found in subtropical waters and often around coral reefs. They can grow up to about 18 inches long and a prime specimen might weigh a couple of pounds. The markings are quite variable but one common characteristic seems to be a tendency to look somewhat down in the mouth; and to possess jaws full of tiny sharp teeth.

Sand Diver - ©Melinda Riger @ GB Scuba

Sand divers have two rows of teeth on their upper jaw and three rows on their lower jaw. Not content with that, they also have rows of teeth on the palate and tongue. Were they 50 times the size, they would be truly awesome.

Sand Diver ©Melinda Riger @ G B Scuba

The rather primitive appearance of the sand diver is explicable from fossils, which show that their forbears  were active in the Jurassic / Cretacean periods.

Sand Diver ©Melinda Riger @ GB Scuba

HOW DO THEY GET THEIR NAME?

Sand divers often bury themselves in the sand with only their head showing. They are so-called ‘ambush predators’, and burial is one method they use. Another is simply to lie on the sandy bottom, or on reef surfaces and wait for passing prey. Their colouring provides very good camouflage.Sand Diver Fish

WHAT’S ON A SAND DIVER MENU?

A good mix of small reef fishes. Bar jacks, blue chromis, wrasses, fairy basslets, small grunts and so forth. At their own level they are quite fearsome predators.

Sand Diver © Melinda Riger @ Grand Bahama Scuba

ARE THEY ON THE HUMAN MENU?

Well, I knew someone would ask that, so I carried out a search. The answer seems to be no. I have found nothing to suggest that they are edible, or that anyone has tried (or if they have, survived to tell the tale). Incidentally, the best way to find out if something is edible by humans is to search for a recipe. There are no sand diver recipes.

STOP PRESS Jason Knight has drawn my attention to a comment in WhatsThatFish.com (no relation) by one ‘Jenny’, who commends Sand Divers as food (“they cook up just as good as hogfish!”). So yes, they are edible and there is one recipe… 

Sand Diver ©Fred Riger @ G B Scuba

All photos: Melinda Riger of Grand Bahama Scuba

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WTF? (WHAT’S THAT FISH) (5): THE FILEFISH


Scrawled Filefish ©Melinda Riger @ GBS

WTF? (WHAT’S THAT FISH) 5: THE FILEFISH

The jocularly-named WTF? series is designed to shed an underwater spotlight on some of the odder denizens of the coral reefs and surrounding waters. I don’t want to earn a reputation for being ‘lookist’, but frankly the appearance of some of these creatures – I give you BATFISH or FROGFISH or REMORAS as examples – is baffling. The filefish group is not as extreme as some in the downright weird category, but if you see one you might just find yourself muttering into your facemask “wtf?”

Scrawled Filefish ©Melinda Riger @ G B Scuba

Filefish (Monacanthidae) are found in tropical and subtropical oceans worldwide. They are related to triggerfish, trunkfish and pufferfish, and have regional names that include leatherjacket, foolfish, and shingle. There are more than 100 species of filefish, of which only a few are found in Bahamian waters. The species featured here are a mix of scrawled, white-spotted and orange-spotted filefish.

Filefish White-spotted ©Melinda Riger @G B Scuba

HOW DID THEY GET THE NAME?

In the image above, you can just see a flattened spine on top, above the eye and pointing backwards. This is the ‘retracted’ state. There is a small secondary spine that serves to prop up the main spine when it is in the upright position. This is it seems, the file – although the Greek-derived family name Monacanthidae literally means ‘one thorn’. So why isn’t it a thornfish, you may well ask. And I may well not respond.

This filefish’s ‘spine’ seems to have flopped over to one sideWhite Spotted File fish

These fish have snouts with small mouths and specialized teeth with an inner and outer set on each jaw. They are to an extent shapeshifters, and can quickly make themselves appear larger for defensive purposes. In some individual species, there are marked differences in body shape and coloration.

An orange-spotted filefish with its spine erect, making for a cave – a place of safetyFilefish, Orange Spotted ©Melinda Riger @ GB Scuba

The fins of a filefish are small, and they are rather sedate swimmers. Sometimes they simply like to drift with their heads pointed downwards, eyeing patches of seagrass or seaweed for prey. Some species are largely vegetarian. Others eat small invertebrates. Some even feed on corals. Their predators – especially  the juveniles –  include tuna and dolphins (mahi-mahi).
ADDITION Capt Rick Guest has helpfully expanded on juvenile filefish: “The juveniles hang under sea weed and flotsam eating small shrimps and crabs there. They, in turn become food for Mahi and other pelagic fish. The main thing with these guys is that the bigger they are, the more likely they are to be Ciguateric”.
220px-Coryphaena_hippurus
At his suggestion I will write a post about the  problem of the Ciguatera disease when I have had some time to do the research.

Scrawled File Fish

ARE THEY EDIBLE?

Good question. The answer, broadly is yes, though I don’t know if that applies to all species of filefish. They are certainly eaten in large quantities in the Far East. I don’t know about the Bahamas or the wider Caribbean. If anyone does, could you very kindly add a comment to this post. Recipes welcome!

Scrawled Filefish

All photos: Melinda Riger of Grand Bahama Scuba

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ATLANTIC SPADEFISH: BAHAMAS REEF FISH (28)


Atlantic Spadefish ©Melinda Riger @ G B Scuba copy 2

ATLANTIC SPADEFISH: BAHAMAS REEF FISH (28)

The Atlantic spadefish looks very much like an angelfish, and indeed it is called that – or ‘white angelfish’ – in some places. Actually, it has quite a collection of colloquial names of which ‘moonfish’ is the most attractive sounding. It is not a true angelfish, however, and despite appearances it has a kinship with the weird and wonderful BATFISH.

Atlantic Spadefish ©Melinda Riger @GBS

Unlike the batfish, the spadefish is demonstrably fishlike AND edible. They can grow up to 3 foot long and have become a popular gamefish for three good reasons: they are abundant; they fight hard; and they are dinner. The perfect combination.

Atlantic Spadefish ©Melinda Riger @ G B Scuba copy

All photos: Melinda Riger of Grand Bahama Scuba, with thanks

Atlantic Spadefish ©Melinda Riger @ G B Scuba

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“OPHELIA READY FOR HAMLET”: BAHAMAS REEF FISH (27)


Indigo Hamlet ©Melinda Riger @G B Scuba

“OPHELIA READY FOR HAMLET”: BAHAMAS REEF FISH (27)

It’s a couple of years since I originally posted about the various species of HAMLET that inhabit the reefs of the Bahamas. I feel you are (geddit?) ready to see some more of these colourful little fish. Last time out, I worked over the Shakespearean possibilities quite thoroughly so I’ll spare you a repeat (apart from the inevitable title pun). If you really want to revisit the famous Hamlet Cigar ad or hear the theme music (Bach’s Air on a G String, shamelessly ‘borrowed’ by Procol Harum for ‘A Whiter Shade of Pale), you’ll find them HERE. Or just move straight on to 5 related but very different looking Hamlets cruising the Bahamas coral reefs.

INDIGO HAMLETIndigo Hamlet ©Melinda Riger@ G B Scuba

BARRED HAMLETBarred Hamlet ©Melinda Riger @ GB Scuba Barred Hamlet ©Melinda Riger @ Grand Bahama Scuba

BLACK HAMLETBlack Hamlet ©Melinda Riger @ GB Scuba

SHY HAMLETShy Hamlet ©Melinda Riger @ GB Scuba

BUTTER HAMLETButter Hamlet ©Melinda Riger @ Grand Bahama Scuba

Credits: all photos Melinda Riger of Grand Bahama Scuba

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MAKE FRIENDS WITH ANEMONE: BAHAMAS REEF LIFE


Anemone (Giant) ©Melinda Riger @GBS copy

MAKE FRIENDS WITH ANEMONE: BAHAMAS REEF LIFE

The giant anemone is found in the shallow reefs and lagoons of the Caribbean and western Atlantic. These are, of course, animals and not plants, with many tentacles that surround their mouth. They attach themselves to rock or in rock crevices, mooring themselves securely against the swell of the waves.  

Giant anemone with ‘Speckles’, a spotted moray eelGiant Anemone & Speckles ©Melinda Riger @ G B Scuba copy

ARE THEY USEFUL?

One important feature of a healthy anemone population is the shelter they give to certain small fish and cleaner shrimp species. They act as bases for FISH CLEANING activities, a vital role in the undersea community.

Giant Anemone ©Melinda Riger @ G B Scuba copy

HOW DO THEY HAVE… ERM… SEX?

The sex lives of anemones seems particularly complicated (as they would doubtless think about humans). Cutting to the chase, reproduction involves the synchronous spawning of eggs and sperm, with fertilisation occurring in the surrounding water. The fertilised eggs become larval and spread in the water column, which increases their chances of survival. They settle on the BENTHOS, where they develop a “pedal leg” (rather in the manner of a gastropod) which in due course they will use to move from A to… A plus a very short distance.

Giant Anemone ©Melinda Riger @ G B Scuba copy 4

These anemones come in many colours. The tentacles often have tips of various hues, and are the only free-floating part of the animal. The body is safely attached to the rock. 

The giant anemone has primitive defensive mechanisms. It needs them, because it crawls so slowly that successful escape by moving is unlikely. Instead they reduce their size by drawing their tentacles into, or as close as possible to, their gastric cavity. They make room for this by forcing most of the water out. This reduces their overall size and of course removes – or at least diminishes – the ”50 colourful tentacles waving around” predator-magnet problem. But also…
Giant Anemone ©Melinda Riger @ G B Scuba copy 7
…they have a trump card. The tips of the giant anemones’ tentacles are packed with cells that contain a toxin. When stimulated, the cells (‘nemocysts’) “explode out of the capsule, impaling the attacker”. The toxin is then discharged, causing extreme pain and paralysis. How cool is that? It’s the superpower we’d all like to have! Or is that just me?
This is also how an anemone feeds, by quickly paralyzing its prey with the ‘toxic tentacles of doom’. The prey is moved to the mouth and swallowed whole…
Giant Anemone ©Melinda Riger @ G B Scuba copy 6
Credits: Melinda Riger of Grand Bahama Scuba, with thanks as always
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CREOLE WRASSE: SHADES OF DEEP PURPLE…


Creole Wrasse ©Melinda Riger @ G B Scuba copy 4

CREOLE WRASSE: SHADES OF DEEP PURPLE…

The creole wrasse is a small wrasse species, with adult males reaching about 12 inches long. During its life, a creole wrasse changes colour significantly.  A juvenile is almost completely violet-purple. As it matures, it develops patches of yellow on the rear part of its body.

Creole Wrasse ©Melinda Riger @ G B Scuba copy 7

Creole wrasse are found throughout the tropical and subtropical waters of the western Atlantic from Florida south to Brazil. The habitat includes Bermuda, the Caribbean Sea, and the Gulf of Mexico.

Creole Wrasse ©Melinda Riger @ G B Scuba copy 5Creole Wrasse ©Melinda Riger @ G B Scuba copy 6

Creole wrasse are social fish that live in groups around coral reefs. They are found in shallow water, but may also be seen as deep as 100m. 

Creole Wrasse at a cleaning station ©Melinda Riger @ G B Scuba copy

The groups of wrasse feed on plankton, small jellyfish, pelagic TUNICATES, and invertebrate larvae. These fish are active in groups by day. At night each fish finds its own safe crevice in the reef to sleep.

Creole Wrasse School ©Melinda Riger @G B Scuba copy

ANYTHING ELSE WE NEED TO KNOW?

Yes indeed. Their intriguing breeding regime – how unlike our own dear species. The creole wrasse is a protogynous hermaphrodite.  The largest fish in a group is a dominant breeding male, while smaller fish remain female. If the dominant male dies, the largest female changes sex. The mature males congregate at leks to breed, at which they display and are approached by females before mating with them. [note: these leks are reminiscent of certain clubs in the less reputable parts of some towns and cities. Or so I am told]

Creole Wrasse Melinda Riger @ G B Scuba copy

It’s been a while since the last Rolling Harbour musical diversion, but the colour of this wrasse nudged my memory back to 1968 and DP’s first album (line-up Mk 1 of several hundred, or so it seems). Hence the post title. Anyone who remembers this ‘wasn’t there’. Anyone who doesn’t obviously wasn’t there either…

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I don’t think this guy thinks much of that. And quite right tooCreole Wrasse ©Melinda Riger @GBS copy

All phish photos by Melinda; DP cover borrowed from Am@z@n; MP3 moi

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HIP! HIP! HIPPOCAMPUS: LET’S CELEBRATE SEAHORSES


Seahorse (Bahamas) 4 ©Melinda Riger @G B Scuba

HIP! HIP! HIPPOCAMPUS: LET’S CELEBRATE SEAHORSES

Melinda Riger, doyenne of the deep and photographer to the stars (brittle stars, basket stars, starfish etc), undertook her 5000th dive a few days ago. She swims with sharks almost daily, and points her lens at the varied reef life she encounters along the way. Her gold prize for the dive turned out to be one of the smallest creatures she encountered: the seahorse. Hippocampus (Ancient Greek: Ἵππος, horse and Κάμπος, sea monster) is a unique fish, deriving from the pipefish, with more than 50 species known worldwide. I can feel a Rolling Harbour fact list coming on…

Seahorse (Bahamas) 3 ©Melinda Riger @G B Scuba

10 SEAHORSE FACTS TO DAZZLE YOUR FRIENDS WITH

  • Only seahorses and razorfish swim upright / vertically all the time
  • Their tails are prehensile and enable them to moor on coral, seagrass etc
  • They have no scales, but skin stretched over bony plates arranged in rings
  • The ‘coronet’ on a seahorse’s head is unique to the individual
  • Seahorses are pathetic swimmers: the slowest have a top speed of 5′ per hour
  • They feed by ambush, rotating the head and sucking prey in with their snout
  • A seahorse’s eyes can move independently of each other, like a chameleon 
  • The Bahamas is home to H. erectus and the dwarf seahorse H. zosterae
  • Despite rumours, they don’t mate for life. Some may stay together for a season
  • The smallest seahorse in the world – the pygmy – is a maximum of 15mm long

Seahorse (Bahamas) 2 ©Melinda Riger @G B Scuba

MAKING BABY SEAHORSES: A MOST UNUSUAL ARRANGEMENT

There’s no getting round it: seahorse courtship and reproduction is highly unusual. Here is a summary of how it goes (there’s a lot more to it, but life is short):

  1. COURTING This may last for many days. They may change colour; they swim together; they entwine tails; they attach themselves to the same strand of coral or seagrass and turn slowly round it in unison (a so-called ‘pre-dawn’ dance). The final courtship dance may last several hours while the male & female prepare for the next stage.
  2. EGG TRANSFER When the time is right the female transfers her eggs – hundreds of them – via her ovipositor  to the male, in the process of which they are fertilised. Handily, he has inflated a special egg pouch located on his abdomen. She then buggers off.
  3. GESTATION The fertilised eggs grow inside the egg pouch of the male and develop into baby seahorses. This process may take from 10 days to a few weeks. During this time, the female will visit for a short ‘morning greeting’ and some intertwining action.
  4. ‘BIRTH’ In due course the male ejects the baby seahorses from his pouch using muscular contractions. These may number from five to (get this!) 2,500 at a time; on average 100–1000. Job done. Then the tiny seahorse babies are on on their own…

Seahorse (Bahamas) 1 ©Melinda Riger @G B Scuba

THREATS TO SEAHORSES

The attrition rate of baby seahorses through predation is high (as for most fish species), but the prolific breeding rate reduces the effect on the overall populations.  As so often, there are human-related threats, not least habitat destruction, overfishing and pollution. There’s a less expected problem: the importance of seahorses in Chinese medicine.  Their presumed healing qualities are used to treat impotence, wheezing, enuresis, pain and to assist labour. For these purposes, some 20 million seahorses a year are caught and sold. Increasingly they are reduced to pill or capsule form. 

Seahorse values depend on the species, but weight for weight dried seahorses retail for *unbelieving face* more than the price of silver and almost that of gold in Asia, from US$600 to $3000 per kilogram. Ours not to reason why.

anagram

USELESS SEAHORSE FACTS

  • Seahorse is an anagram of seashore
  • The Seahorses were an English rock band, formed in 1996 by guitarist John  Squire following his departure from The Stone Roses. They split in 1999
  • Devendra Banhart’s song ‘Seahorse’ contains these inspiring lyrics:
    I wanna be a little seahorse
    I wanna be a little seahorse
    A little seahorse
    I wanna be a little seahorse
    I wanna be a little seahorse
    I wanna be a little seahorse
    I wanna be a little seahorse
  • I’m losing the will to live. Let’s meet Otis.

Introducing Otis, Melinda’s seahorse that lives under her dockSeahorse (Otis), Bahamas ©Melinda Riger @ G B Scuba

SEAHORSE MATING DANCE (4 MINS)

MALE SEAHORSE GIVING BIRTH

All photos: many thanks to Melinda Riger of Grand Bahama Scuba; sources, many and manifold including Wiki which is pretty good on this kind of thing! Fab seahorse gif by Alex Konahin 

Seahorse by Alex Konahin copy

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‘BAHAMAS SHRIMPING’: BANDED CORAL SHRIMPS


Banded Coral Shrimp ©Melinda Riger @ G B Scuba copy 2

‘BAHAMAS SHRIMPING’: BANDED CORAL SHRIMPS

The Banded Coral Shrimp Stenopus hispidus is also known as the banded cleaner shrimp because it cleans other fish (see TAKEN TO THE CLEANERS); and ‘boxing shrimp’ because its stance and the large pincers on the third set of legs give the creature the appearance of a boxer ready to fight.

Banded Coral Shrimp Stenopus hispidus (Johan Fredriksson) a

These shrimps are widely distributed in tropical and sub-tropical waters around the world where coral reefs are found. Their striking colour scheme makes them instantly recognisable.

Banded Coral Shrimp (Alexander Vasenin) a

BANDED CORAL SHRIMP ON STAR CORAL AT NIGHTBanded Coral Shrimp on Star Coral (night) - LASZLO ILYES

 BANDED CORAL SHRIMPS: 10 FACTS TO BANDY ABOUT

  • BCSs are decapods, having 5 matching pairs of legs / claws on each side
  • They can be found as deep as 200 metres in the ocean
  • They are also found in aquaria, but need careful management because…
  • They are generally aggressive to other BCSs & shrimps in the same tank and
  • They need room for their long legs and antennae to move freely around
  • However, rather sweetly, they are monogamous and do not eat their partners
  • Diet-wise they are omnivore carnivore scavengers
  • They are said to be amusing to watch as they rush round a tank after food
  • Not a good shrimp to breed: the larvae get stuck in the filtration or get eaten
  • In the sea, they act as ‘cleaner’ fish to larger fish species (see below)

Banded Coral Shrimp ©Melinda Riger @ G B Scuba Banded Coral Shrimp (+ Moray Tail) ©Melinda Riger @ G B Scuba copy

In its capacity as a cleaner shrimp, the BCS solicits passing fish by slowly waving its long, white antennae. It then uses its three pairs of claws to remove parasites, fungi and damaged tissue from the fish. See the video example below.

A Banded Coral Shrimp (Stenopus hispidus).

BANDED CORAL SHRIMP CLEANING A PASSING YELLOW TANG

BANDED CORAL SHRIMPS IN A VASE SPONGE

Credits: Melinda Riger (Grand Bahama Scuba); Johan Fredriksson; Alexander Vasenin; Laszlo Ilyesr; R. Ling; LiveAquaria, Fishlore [nb not all pics are from the Bahamas, but the BCS is the same the world over…]

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CARIBBEAN REEF SQUID: SUPERPOWERS & SEX LIVES REVEALED


Squid ©Melinda Riger @ Grand Bahama Scuba

CARIBBEAN REEF SQUID: SUPERPOWERS & SEX LIVES REVEALED

The Caribbean reef squid Sepioteuthis sepioidea is a small squid species of the Caribbean Sea and the Floridian coast. Its fins extend nearly the whole length of the body and undulate rapidly as it swims. Recently, it has been discovered that this squid is capable of brief flight out of the water.Squid ©Melinda Riger @ Grand Bahama Scuba

Reef squid tend to form small shoals in and around reefs. It is by far the most common squid species in its range, and can be sighted both close to the shore and quite near the surface (although that increases the risk of predation by seabirds).

A silvery squid swimming just below the surfaceCaribbean_reef_squid (Ed Brown)

Squid are voracious eaters, dragging their prey to their mouths and using a beak to cut it up. Their target species are small fish, molluscs and crustaceans. They have a ‘raspy tongue’ known as a radula which further breaks up the food for easy consumption.

Squid at Fowl Cay Marine Preserve, AbacoSquid Fowl Cay, Abaco Ellen Sokol, Kiskeedee Sailing Charters

SQUID SUPERPOWERS (SUPERCOOL)

  • Squid can change colour, texture and shape
  • This enviable power is used defensively as camouflage or to appear larger if threatened
  • It is also used in courtship rituals, something that humans would find most disconcerting
  • Colour patterns are also used for routine squid-to-squid communication AND GET THIS:
  • A squid can send a message to another on one side, and a different one to a squid on the other

Squid © Melinda Riger @ Grand Bahama Scuba copy

SQUID SEX (1) “ROMANCING THE SQUID”

  • A male will gently stroke a female with his tentacles
  • The female will (most likely) flash an ‘alarm’ pattern
  • The male soothes her (don’t try this at home, guys) by blowing and jetting water at her
  • If he’s not getting on well, he’ll move off and repeat the routine until she sees his good points
  • However this on / off courtship can last for hours until at last he succeeds by…
  • …attaching a sticky packet of sperm onto the female’s body (romance is not dead)
  • She reaches for it and moves it to her “seminal receptacle”
  • Meanwhile he stays close, emitting a pulsing pattern, as well he might after all that
  • She then finds a safe place to lay her eggs. Job done.Two_Caribbean_Reef_Squid,(Clark Anderson)

SQUID SEX (2) IT ALL ENDS BADLY

  • As soon the female squid has laid her eggs, she dies at once
  • The male squid live a bit longer, and may have other packets to stick – then he dies too
  • It’s all horribly reminiscent of Romeo and Juliet. Without the balcony scene.Sepioteuthis sepioidea Caribbean Reef Squid (Nick Hobgood)

USES OF SQUID ON ABACO

Squid are prolific in the seas around Abaco, which is fortunate because they form a large part of the diet of some whale species, particularly the Blainville’s Beaked Whales that are commonly found in Abaco waters. I have a post on these magnificent creatures in preparation right now, and am in the process of sorting out suitable photos from a large number taken during a research expedition in March. 

More Squid at Fowl Cay Marine Preserve, AbacoSquid School, Fowl Cay, Abaco Ellen Sokol, Kiskeedee Sailing Charters

Credits: As ever (for underwater pics) Melinda Riger of Grand Bahama Scuba; also Ellen Sokol of Kiskeedee Sailing Charters, who kindly sent me the Fowl Cay photos; also Ed Brown, Clark Anderson and Nick Hobgood for ‘open-sourcing’ their great images

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“THE BUTTERBUN” (LONGSNOUT BUTTERFLYFISH): BAHAMAS REEF FISH (26)


Longnose : Longsnout Buttefly Fish ©Melinda Riger @ G B Scuba copy

“THE BUTTERBUN” (LONGSNOUT BUTTERFLYFISH)

BAHAMAS REEF FISH (26)

The Atlantic/ Caribbean Longsnout Butterflyfish Prognathodes aculeatus is sometimes known locally as the Longnose (not to be confused with the bright yellow Indo-Pacific Longnose Butterflyfish). The affectionate name for it is ‘Butterbun’. A more scientific name is ‘Poey’s Butterflyfish’, named for the man who first identified the species in 1841.

Mr Felipe Poey

Longnose : Longsnout Butterflyfish  © Melinda Riger @ GB Scuba copy
These little fish, 2 0r 3 inches long, are commonly found on reefs from Florida down to Venezuela. Unlike most butterflyfishes, they prefer deeper water and have been found at 200 ft; and they tend to be solitary rather than gregarious.
Longnose: Longsnout Butterflyfish ©Melinda Riger @ G B Scuba copyLongsnout Butterflyfish (www.whatsthatfish.com)
BUTTERBUN. THAT SUGGESTS THEY ARE PLUMP?

Longsnout Butterflyfish (π Florent's Reef Guide)NOPE!Longsnout Butterflyfish Prognathodes aculeatus (Wiki)

RELATED LINKS

BUTTERFLYFISHES (RH guide to reef, banded, four-eyed & spotfin)

REEF FISH INDEX gateway to loads of colourful finny species

WHAT’S THAT FISH? A handy resource

FLORENT’S GUIDE A ditto

Longnose : Longsnout Butterflyfish ©Melinda Riger @GB Scuba copy

Credits: Melinda Riger for her brilliant underwater images (as marked); plus What’s That Fish?, Florent’s Guide and good old Wiki…

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FORAYS WITH MORAYS (3): LET’S GO GREEN…


Green Moray Eel with Soldierfish (Melinda Riger @ G B Scuba)

FORAYS WITH MORAYS (3): LET’S GO GREEN…

A short while back I posted about SPOTTED MORAYS, which people seem to enjoy. It generated requests for more forays, specifically with green morays. I gotcha – here they are, as promised… All the eels shown below, familiar to the divers who regularly encounter them and given names such as “Judy’ and “Wasabi” (my favourite), were photographed by Scuba expert Melinda Riger, whose skills with a camera are well-known. Let’s go Green…

Like all moray species, Greens like to lurk in convenient hiding places to watch the underwater world – and possible prey – go by. Here are some typical ‘lurking’ shots.Moray Eel, Green, with lunch (eel) emerging from gill ©Melinda Riger @ Grand Bahama Scuba Green Moray Eel ©Melinda Riger @ GB Scuba copy

Green Moray Eel (Judy) ©Melinda Riger @ G B Scuba Moray Eel, Green (Wasabi) ©Melinda Riger @ GB Scuba Green Moray Eel ©Melinda Riger @ GB Scuba

Green morays also have the unusual breathing apparatus that resemble nasal plugsGreen Moray Eel Melinda Riger @ G B ScubaGreen Moray Eel ©Melinda Riger @ Grand Bahama Scuba

Those who recall the spotted moray post and their singular dentition arrangements that included a long sharp tooth sticking down from the upper jaw will no doubt be thinking, “are we going be shown any dental close-ups?” But of course… why would I not?

Note the cluster of teeth in the upper jaw, differing from the spotted morayMoray Eel (Yellow) Judy ©Melinda Riger @ G B Scuba

Grrrrrrrrrrrrrrr…….Moray Eel, green ©Melinda Riger @ G B Scuba

All photos: Melinda Riger, Grand Bahama Scuba

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WTF? (WHAT’S THAT FISH?) (5): THE FROGFISH


Frogfish (Adam Rees, Scuba Works)

WTF? (WHAT’S THAT FISH?) (5): THE FROGFISH

This ‘WTF?’ series started with a relatively conventional species, the REMORA. It has been getting progressively more bizarre. We moved onto an omnium gatherum of WEIRDO FISHES, then the remarkable LETTUCE SEA SLUG, and most recently the BATFISH. Time to ramp up the stakes: with many thanks to scuba expert Adam Rees for use permission for his terrific photos, I present… the FROGFISH.

Frogfish (Adam Rees, Scuba Works)

The frogfish is a kind of anglerfish found in almost all tropical and subtropical oceans and seas. There are about 50 different species worldwide, covering an astonishing range of strange appearances. They generally live on the sea floor around coral or rock reefs. In size they vary from tiny to about 15 inches long – although ‘long’ is a flexible concept because they are to an extent shape-changers in height and width.Frogfish (Adam Rees Scuba Works)

FROGFISH SUPERPOWERS YOU MAY WISH TO HAVE

  • INVISIBILITY CLOAK . Frogfish are masters of disguise and camouflage. This enables them to catch their prey with minimal effort and also to avoid predators. Their camouflage methods – broadly known as ‘aggressive mimicry’ – include
    • Ability to change colour for days or even weeks to mimic their surroundings
    • Getting covered in algae and other organic matter that matches their habitat or
    • Looking inherently like a plump rock or in some cases, plant

Fear for the life of the spider crabFrogfish (Adam Rees, Scuba Works)

  • IRRESISTIBLE ATTRACTION (just like that nice Mr Grey)
    • A sort of frontal dorsal fin called an illicium to which is attached a
    • Lure called an esca which may mimic a worm, shrimp or small fish etc and which is
    • Retractable in many species and
    • Regenerates if it gets mislaid

The ‘dollop of cream’ thing is the esca. Note the characteristic large mouthFrogfish (Adam Rees, Scuba Works)

Spot the escaFrogfish (wiki)

  • BUOYANCY CONTROL & SHAPE-SHIFTING
    • Most frogfish have a ‘gas bladder’ to control their buoyancy.
    • Some species can change shape or even inflate themselves by sucking in quantities of water in a so-called defensive ‘threat display’.

frogfish-black

Frogfish (Adam Rees Scuba Works) Frogfish (Adam Rees Scuba Works)

HOW DO FROGFISH REPRODUCE? 

Although not conventionally attractive creatures, frogfish clearly manage to reproduce. Little is known about the techniques in the wild, but one is probably ‘with care’, especially for a male frogfish who may not survive for long if he hangs around after fertilisation has taken place. It has been noted that females tend to select far smaller males to fertilise their huge numbers of eggs, perhaps for that very reason.

Frogfish (Adam Rees, Scuba Works)

FROGFISH FEEDING SKILLS – GOOD OR BAD?

When deploying the lure, potential prey that comes too close to that wide mouth stands no chance. A frogfish will strike in a fraction of a second. Frogfishes have voracious appetites for crustaceans, other fish, and even each other. I can do no better than borrow this vivid description of a feeding frogfish:

“When potential prey is first spotted, the frogfish follows it with its eyes. Then, when it approaches within roughly seven body-lengths, the frogfish begins to move its illicium in such a way that the esca mimics the motions of the animal it resembles. As the prey approaches, the frogfish slowly moves to prepare for its attack; sometimes this involves approaching the prey or “stalking” while sometimes it is simply adjusting its mouth angle. The catch itself is made by the sudden opening of the jaws, which enlarges the volume of the mouth cavity up to twelve-fold, pulling the prey into the mouth along with water. The attack can be as fast as 6 milliseconds. The water flows out through the gills, while the prey is swallowed and the oesophagus closed with a special muscle to keep the victim from escaping. In addition to expanding their mouths, frogfish can also expand their stomachs to swallow animals up to twice their size.

images

HOW DO FROGFISHES GET AROUND? SWIM? WALK? CRAWL?

Frogfishes do not in fact move around a great deal. Using their camo advantages, they prefer to lie on the sea floor and wait for prey to come to them. As mentioned in the quote above, they may slowly approach prey using their pectoral and pelvic fins to “walk” along the sea bottom. They can swim using their tail fin (or in some species by simple ‘jet propulsion’ by forcing water out of their gills) but rarely do so – they don’t feed on the move, and they are adapted to the sea floor environment where they food is readily available. However their “walking” ability is limited to short distances.

frogfish-anglerfisch

DO FROGFISH HAVE OTHER COLOUR SCHEMES?

Indeed they do. In stark contrast to the camo species, some frogfishes are highlighter bright. Here are two of my favourite photos by Adam that show this clearly. I’ve no idea if these are a male and female. I suspect they are different species. I think the brown one is a striated frogfish and the other is… a yellow frogfish. Some people keep these creatures in  aquaria, but apparently it is impossible to sex them, and they have to be kept on their own for everyone’s peace of mind…

Frogfish (Adam Rees Scuba Works) Frogfish (Adam Rees Scuba Works)

FROGFISH INFOGRAPHICS

frogfishFrogfish Infographic 'Monsters of the Deep'

FROGFISH VIDEOS

These two videos, from Lester Knutsen and Daan Van Wijk respectively, show some of the characteristics I have written about above. Both are short and both are fascinating.

To read more about frogfishes and for some fabulous photos I highly recommend the website FROGFISH.CH You can reach the main page(s) but the link seem to be broken so I have not been able to contact Teresa Zubi, whose site it is. She clearly has a sense of humour and uses a neat pair of gifs which I hope she won’t mind my using…

Credits: All main photos, Adam Rees  of Scuba Works with many thanks; wiki for ‘spot the esca’, red quote & basic info; videos Lester Knutsen & Daan Van Wijk; Teresa Zubi for website & gifs; infographics, authors u/k

Frogfish Tee Shirt