WTF? (WHAT’S THAT FISH?) 17: YELLOWHEAD JAWFISH


Yellowhead Jawfish (Melinda Riger / Grand Bahama Scuba)

WTF? (WHAT’S THAT FISH?) 17: YELLOWHEAD JAWFISH

It’s been a little time since I added to the WTF? series, in which some of the more outlandish reef denizens come under close scrutiny. Jawfishes (Opistognathidae) come into this category, not least because of their interesting ways with their eggs. Also, they tend to stick upright out of the substrate, which is not especially fishy behaviour.

Yellowhead Jawfish (Melinda Riger / Grand Bahama Scuba)

More than 50 species of jawfish are found around the world. In the Bahamas, you are most likely to encounter the Yellowhead (or Yellow-headed) variety. And if you think they look slightly… primitive, that’s because they are. In fact, their forebears (forefishes?) originated in prehistoric times, specifically the Miocene era (a lot of million years ago, I didn’t count exactly).

Yellowhead Jawfish (Melinda Riger / Grand Bahama Scuba)

These rather extraordinary little fish superficially resemble certain types of BLENNY. Their modus operandi is to burrow down into sandy, gravelly or other loose substrate. They do so by cramming their mouths with sand and spitting it out to one side. By this means they form a tunnel of sorts in which they can live, and from which they can emerge, or half-emerge and take a look around them. As they do so, they hoover up passing food, mostly plankton and suchlike.

Yellowhead Jawfish (Virginia Cooper / Grand Bahama Scuba)

If something looks threatening while they are feeding or having a look around, they can simply duck down into their burrow for safety. They guard their patch against rivals, and behave ‘territorially’ in the jawfish community. One method is to ingest and and then eject sand or gravel at a would-be intruder.

Yellowhead Jawfish (Michael Wolf Wiki))

YES, BUT WHERE IS THE REAL ‘WTF?’ FACTOR HERE?

Good question. With a good and original answer. These little creatures are so-called MOUTHBROODERS‘, meaning that they carry their eggs in their mouths. Depending on the species, females, males or even both parents (don’t try this at home) will do this at or after fertilisation. In effect the eggs are safely incubated until they hatch as fry. Then they are on their own.

Yellowhead Jawfish (Melinda Riger / Grand Bahama Scuba)

ARE THERE ANY DRAWBACKS TO THIS UNUSUAL GESTATION METHOD?

Apart from accidentally swallowing the occasional potential junior, the eggs need aeration from time to time. This is achieved by expelling the eggs from the mouth, and quickly sucking them back in again. Try this very short video to see this rather improbable behaviour in action. It’s only 8 seconds blink and you’ll miss the action. The eggs hatch into fry in 8 – 10 days, after which both parents can relax. Until the next time.

Yellowhead Jawfish (Melinda Riger / Grand Bahama Scuba)
Photo Credits: all images from Melinda Riger / Grand Bahama Scuba except (4) Virginia Cooper / GBS; (5) Michael Wolf / Wikimedia; video, Alan Keller. Research: magpie picking, not excluding yet not limited to Wiki…
Yellowhead Jawfish (Melinda Riger / Grand Bahama Scuba)

BAHAMAS REEF FISH (51): BLACK MARGATE


Black Margate (Melinda Riger / Grand Bahama Scuba)

BAHAMAS REEF FISH (51): BLACK MARGATE

The black margate (Anisotremus surinamensis) is a type of GRUNT (see also PORKFISH) found among the reefs and rocks of (mostly) the western Atlantic seaboard, from Florida as far south as Brazil. They are relatively ‘shallow’ fish and they prefer to be close to place where they can live safely and avoid the predators that lurk in open or deep water.

Black Margate (Melinda Riger / Grand Bahama Scuba)

Margates are not usually very large, mostly growing to between 18″ and 30″, although they can grow larger. Thanks to the awesomeness of Wiki and other reliable sources I can confidently report that “…the maximum recorded weight for this species is 5.8 kg (13 lb)“.

Black Margate (Melinda Riger / Grand Bahama Scuba)

MAY WE HAVE THE TRADITIONAL 10 FUN FACTS PLEASE?

  • Local names include burriquete (Sp) and zapatero or burros (Mex)
  • There are 10 margate species world wide, including 2 Pacific versions
  • Their heads slope down to a notably thick lipped mouth in which they have strong teeth
  • Margates have erectile spines, presumably for defence (I’ve not tested that)
  • They like to shelter in caves and crevices, on ledges, and in wrecks (see pics)
  • Margates are ‘solitary fish’ or hang out in small groups
  • They are night-feeders on a diet of crustaceans, mollusks, smaller fish & urchins
  • Sadly for them, they are valued by commercial fisheries using baited drift fishing…
  • …and also targeted by anglers during the spawning season when they shoal (?unfair)
  • … and also caught as aquarium fish, adding to stock depletion

Black Margate (Melinda Riger / Grand Bahama Scuba)

RELATED SPECIES

PORKFISH

Credits: all photos, Melinda Riger / Grand Bahama Scuba; research from magpie pickings and in particular the interesting mexicanfish.com

Black Margate (Melinda Riger / Grand Bahama Scuba)

FORAYS WITH MORAYS (6): WELL SPOTTED…


Spotted Moray Eel (©Melinda Riger / Grand Bahama Scuba)

FORAYS WITH MORAYS (6): WELL SPOTTED…

I was always taught ‘keep your mind open and your mouth closed’. Bad advice. Such bad advice. The worst. So many reasons to be exactly the opposite in these troubled times…

Spotted Moray Eel (©Melinda Riger / Grand Bahama Scuba)

Spotted Moray eels Gymnothorax moringa, however, seem to have their own rules to live by. They appear to be open-minded and fairly sensible creatures around the reef. They tend to keep themselves to themselves, hanging out unassumingly in holes and crevices in the coral.

Spotted Moray Eel (©Melinda Riger / Grand Bahama Scuba)

They do tend to stick their necks out a bit, but unless provoked (see below) they seem to be reasonably amiable (except maybe to the small fish and crustaceans that make up their diet).

Spotted Moray Eel (©Melinda Riger / Grand Bahama Scuba)

They do keep their mouths open a lot, though. And as you can see, they have sharp-looking teeth that you mightn’t want too near to you. I say that because their bite can be dangerous and should be avoided. To start with, the teeth are slightly backward-facing, so that when they bite there is a ‘pull-back’ effect when you react (not unlike a barb on a fish hook). They are not aggressive as such, but they know how to deal with unwanted interference in their lives…

Spotted Moray Eel (©Melinda Riger / Grand Bahama Scuba)

Apart from the unpleasant bite and associated pain that moray eels can inflict in defence, they are also poisonous (as opposed to venomous). Specifically they can release toxins into the wound; and in some species their skin contains toxins as well**. Serious infection may result.

Spotted Moray Eel (©Melinda Riger / Grand Bahama Scuba)

CAN YOU GIVE THE POISONOUS / VENOMOUS DISTINCTION AGAIN

I could, but ace natural history cartoonist Rosemary Mosco makes a better job than I can:Toxic: poison v venom cartoon (Rosemary Mosco)

**Before I leave the topic, maybe I ought to mention one bit of research I have just come across at Dove Med, from which I take away the message that you definitely don’t want to annoy a moray eel or get bitten by one. Ever. They are fine and interesting denizens of the reef, to be admired from a respectful distance…

Spotted Moray Eel (©Melinda Riger / Grand Bahama Scuba)

Photo credits: all amazing photos courtesy of Melinda Riger, Grand Bahama Scuba; cute yet educative cartoon by Rosemary Mosco. Check out her website HERE – and birders, she v good on your specialist subject…

Spotted Moray Eel (©Melinda Riger / Grand Bahama Scuba)

BAHAMAS REEF FISH (50): TOBACCO BASSLET


Tobacco Basslet (Serranus tabacarius) Bahamas (Melinda Riger / GB Scuba)

BAHAMAS REEF FISH (50): TOBACCO BASSLET

Welcome to #50 in the Bahamas Reef Fish series. I chose this fish to honour the landmark before thinking about its features. Grumpy. Also, associated with a narcotic and dangerous drug. And a fish one probably wouldn’t bother to smoke (even if one could get it to light underwater). In the Bahamas you’ll find these little fish around the coral reefs where they play their part as reef denizens, which includes being prey to larger species. If one looks them up online, however, the overwhelming impression from the websites and images available is that they exist largely for the benefit of the aquarium industry.

Tobacco Basslet (Serranus tabacarius) Bahamas (Melinda Riger / GB Scuba)

Tobacco basslets (Serranus tabacarius) – more commonly just called tobacco fish or tobaccofish – are related to the HARLEQUIN BASS(LET), a species that was most unfairly included as #9 in my parallel WTF? series among all the seriously weird sea creatures that feature in that category. A wrong I must right one day.

Tobacco Basslet (Serranus tabacarius) Bahamas (Melinda Riger / GB Scuba)

Tobacco fish are considered to be hardy, unaggressive (except towards the tiny fishes and crustaceans they feed on) but apparently they need quite a large tank to hold them. The ocean might be suitably large for the purpose. Especially as it seems that in an aquarium there needs to be a cover on top: “these fish are expert jumpers…“, as one source puts it…

BESIDES THE BAHAMAS & AQUARIUMS WHERE ELSE DO THEY LIVE?

TOBACCO BASSLET RANGE MAP

APART FROM THE HIGH JUMP THING, ANY OTHER TRICKS?

Yes indeed. The Tobacco Basslet is hermaphroditic, like all other members of its genus.

DON’T LEAVE IT AT THAT… HOW DO THEY, YOU KNOW?

I didn’t want you to ask. All their FB pages say “It’s complicated“, but here’s a rough idea…

  • All individuals start life as simultaneous hermaphrodites (with sex organs of both sexes)
  • The largest fish lose their female functions and become active sperm-producing males
  • Each male leads a group of hermaphrodites and protects them from other males 
  • This gives them exclusive rights to the female parts of members of their ‘harem’
  • Sometimes hermies may use their male bits to join in & release sperm – ‘streaking’
  • There are rarer mating strategies… Oh heck, please look at the abstract of a scientific paper for details. I had to! And all because you, gentle reader, asked that question.

With some relief, here is very short video. It probably doesn’t accurately show how Tobacco fish might behave on a Bahamian reef. In captivity, from the look of it, they get pushed around by bigger fish. But maybe, if their co-residents are carefully selected, the bonus is that they don’t risk getting eaten.

OPTIONAL MUSICAL INTERLUDE

There are no songs ever that mention tobacco fish or tobacco basslets (though lots involve bass). And more oddly, apart from a couple of old blues songs the only truly mainstream song about tobacco by name (as opposed to content) is Tobacco Road, a song as frequently and thoroughly covered as an aquarium tank containing jumpy tobacco fish.

Rare photos from the actual sea captured by Melinda Riger of Grand Bahama Scuba; Science Direct plus magpie pickings; Captive Aquatic Ecosytems (video)

I didn’t enjoy this article about me very much. I am NOT grumpy.Tobacco Basslet (Serranus tabacarius) Bahamas (Melinda Riger / GB Scuba)

BAHAMAS REEF FISH (49): BANDED BUTTERFLYFISH


Banded Butterflyfish, Bahamas (Melinda Riger / GB Scuba)

BANDED BUTTERFLYFISH – BAHAMAS REEF FISH (49)

The banded butterflyfish (Chaetodon striatus) is one of several butterflyfish species found in Bahamas waters. There are links to some of the others at the end of this post. The reason for the name is obvious. The purpose of the patterning (striatus) is to act as an adaptive anti-predator defence when seen against the varied landscape of the coral reefs that are its home. 

Banded Butterflyfish, Bahamas (Melinda Riger / GB Scuba)

These little fish tend to be found either singly or in pairs. Two of them together may play a form of chase game among the corals and anemones of the reef. 

Banded Butterflyfish, Bahamas (Melinda Riger / GB Scuba)

Banded butterfishes, like their cousins, have a varied diet that includes small crustaceans, worms, and coral polyps. They also have a valuable role on the reef by acting a cleaner fish for larger species like grunts, tangs and parrot fish. This sort of relationship, where one party benefits from this kind of interaction , is known as ‘commensalism’, one of the 4 types of symbiotic relationship.

Banded Butterflyfish, Bahamas (Melinda Riger / GB Scuba)

RELATED LINKS

LONGSNOUT BUTTERFLYFISH

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

Banded Butterflyfish, Bahamas (Melinda Riger / GB Scuba)

Credits: Melinda Riger / Grand Bahama Scuba

PURPLE VASE SPONGES: BAHAMAS REEF ORNAMENTS


Purple Vase Sponge, Bahamas (Melinda Riger / G B Scuba)

PURPLE VASE SPONGES: BAHAMAS REEF ORNAMENTS

The Purple Vase is an unmistakeable sponge, a colourful reef creature (for they are animals, of course) that stands even out amongst the bright corals that surround it. And like corals, sponges are vulnerable to all the usual threats (mainly human-generated).

Purple Vase Sponge, Bahamas (Melinda Riger / G B Scuba)

Catch them while you can in the clear waters of the Bahamas while stocks last. I say this because as study after study concludes, the prospects of reef-mageddon get closer each year. When the corals die off, so in all probability will the sponges and anemones…

Purple Vase Sponge, Bahamas (Melinda Riger / G B Scuba)

After such a depressing intro, let’s move on to take a positive look at the purple vase sponge. As with all sponges, once a newborn sponge is wafted by the current to a place on the reef, it takes root there throughout its life. There, these attractive sponges exist by filtering the water that surrounds them, separating out plankton to feed on. Static filter-feeders, if you will.

Purple Vase Sponge, Bahamas (Melinda Riger / G B Scuba)

You’ll notice that in some of the photographs, the sponges have guests. These are BRITTLE STARS, and they are often found on – and indeed in – purple vases. This is a form of symbiotic relationship known as commensalism, in which one species benefits and the other is neither benefitted nor harmed. The brittle star gains a shelter and a safe base for feeding; the vase gets a harmless companion. Small fishes benefit from the vases in a similar way.

Purple Vase Sponge, Bahamas (Melinda Riger / G B Scuba)

Besides the impact of damaging human interventions (which may be permanent), extreme weather events also affect reef life and the static inhabitants adversely. Storms and hurricanes can cause localised havoc, but the damage is not necessarily permanent. The reef can in time repopulate naturally and flourish again. Humans can even promote this recovery. The photograph above shows a purple vase sponge that was detached from the reef by Hurricane Matthew in October 2016. Melinda Riger in effect replanted it on the reef and it reattached itself and grew. In due course it even acquired its brittle star occupant. 

Purple Vase Sponge, Bahamas (Melinda Riger / G B Scuba)

*JIMI AND ‘PURPLE VASE’ – A VOLUNTARY MUSICAL DIGRESSION

In an interview with NME Hendrix is reported to have said that Purple Haze “was about a dream I had that I was walking under the sea.” Originally the song was intended to be ‘Purple Vase’, and reflect the psychedelic experience of life on a coral reef. Realising he was getting bogged down by sub-aquatic imagery (he was a non-swimmer), he toked for a while and then ‘Purple Haze’ emerged almost fully formed. He was always far happier kissing the sky than wandering about under the waves. Most covers of the song are pale imitations of the original, but here’s a rather unusual take that succeeds by trying a different approach…

Credits: Melinda Riger / Grand Bahama Scuba for all great photos; magpie pickings for bits and pieces, with a shout-out to ‘Critter Squad’ for its informative site aimed at kids. And amateur grown-ups can benefit too… commensalism in humans; Friend ‘n’ Fellow audio

Purple Vase Sponge, Bahamas (Melinda Riger / G B Scuba)

BAHAMAS REEF FISH (48): SCHOOLMASTER SNAPPER


Schoolmaster Snapper (Melinda Riger @ G B Scuba)

BAHAMAS REEF FISH (48): SCHOOLMASTER SNAPPER

November 1st already, and the first time I am prepared to consider the possibility of the onset of Christmas, with its attendant joys yet complications… Meanwhile, I thought I might have run out of types of reef fish to feature in this series long before I got to 50. Yet here we are, two short of that target, with a species of snapper I haven’t even mentioned before. I am (frankly) a rather feeble swimmer, and do not possess a viable underwater camera. So there’s no way I could show these denizens of the not-especially-deep without heavy reliance on others, in particular the outstanding photos of diver Melinda Riger of Grand Bahama Scuba; and the memorable ones from Adam Rees of Scuba Works that include some of the more obscure species that appear in my WTF? (What’s That Fish) series. 

Schoolmaster Snapper (Melinda Riger @ G B Scuba)

The schoolmaster snapper (Lutjanus apodus) lives among the coral reefs and mangroves of the Caribbean and further north to the northern Bahamas and Florida. Generally they are quite small, not much more than 12- 18 inches. They tend to hang out in ‘schools’, which several sources suggest as the reason they got their common name. But schoolmasters don’t really move around in large groups, do they? It’s school pupils that do that, but ‘Pupil Snapper’ wouldn’t cut it as a fish name I guess.

Schoolmaster Snapper (Melinda Riger @ G B Scuba)

10 SCHOOLMASTER SNAPPER FACTS TO PONDER

  • One pair of upper teeth are so large they protrude when the fish shuts its mouth
  • Their side scales are so arranged that diamond shapes are produced
  • There’s plenty to learn about their fin arrangements, but not necessarily to remember
  • Their jaws don’t open very wide, so their prey tends to be quite small
  • Unlike fish that change sex as they grow, these ones retain their birth gender for life
  • When they spawn they produce their gametes simultaneously, and swim away
  • The fertilised eggs sink to the bottom, where they have to take their chances
  • Though small, they are good to eat and are fished for recreation and commercially
  • Regionally there are specific regulations as to catch length & limits, hook type, bait etc
  • Like all snappers and many other fish species, these fish are associated with ciguatera

Schoolmaster Snapper (Melinda Riger @ G B Scuba)

RECIPES

For those who enjoy cooking (whatever that is), you probably know exactly how you like to cook your snappers. For anyone else, here’s a site that proposes several different ways to cook them, with helpful tips. These seem to apply to all snapper species, most of which are available free in the Bahamas. http://www.allfishingbuy.com/Fish-Recipes/Snapper-Recepies.htm

My favourite schoolmaster snapper photo of those featured hereSchoolmaster Snapper (Melinda Riger @ G B Scuba)

POSSIBLE MEDICAL BENEFITS FROM EATING SNAPPERS

These are alleged to include (except when fried): protection against certain types of stroke, reduction of heart arrhythmia, and defence against certain types of cancer. Don’t take my word for it, though. And definitely don’t rely on a snapper-based diet regime. I think the most that can safely be said is that eating snapper will do you no harm (except when fried) and may conceivably have a marginal benefit on health along with a balanced diet, exercise, minimal alcohol intake and all the routines that we strictly adhere to for a healthy life. In our dreams, anyway.

Schoolmaster Snapper (Albert Kok)

Credits: All great pics by Melinda Riger / GB Scuba except #6 Albert Kok; range map, Wiki. Magpie pickings.

Schoolmaster Snapper (Melinda Riger @ G B Scuba)