ABACO’S 38 WARBLERS: AN ILLUSTRATED ID GUIDE (Pt 1)


Olive-capped Warbler, Abaco Bahamas (©Tom Sheley)

Olive-capped Warbler (resident species), Abaco Bahamas (©Tom Sheley)

ABACO’S 38 WARBLERS: AN ILLUSTRATED ID GUIDE (Pt 1)

IT’S STARTED The great winter migration of warblers and their imminent arrival in The Bahamas is underway. Any day now – if not already – the ‘winter’ / ‘Fall’ (late summer & early spring as well) warblers will be arriving on Abaco. There are 38 warbler species recorded for the main island and the cays. For years, it was just 37. Exactly a year ago, a CANADA WARBLER was seen and photographed by well-known birder Chris Johnson. It was a first for Abaco – and the first-ever report for the Bahamas as well. You’ll find the story HERE.

First-ever Canada Warbler for Abaco & the entire Bahamas: Aug 2018 (Chris Johnson)

Canada Warbler, Abaco Bahamas (1st record) (Chris Johnson)

Canada Warbler, Abaco Bahamas (1st record) (Chris Johnson)

This post is the first of 3 warbler posts for the Fall. A while back I compiled a basic (in retrospect) guide to Abaco’s warbler species. I’ll give a link and pdf in due course once I have rechecked (improved? rewritten?) it. [Note: of no value on eBay, @m@z@n or anywhere else]. Many of the warblers are far from easy to distinguish from each other. For example, many males have yellow or yellow-and-black plumage. The females are invariably less colourful – often brownish or olive – than the males (as are juveniles), and that can lead to confusion – and not only by me, I think.

Hooded Warbler, Abaco Bahamas (Chris Johnson)

Hooded Warbler, Abaco Bahamas (Chris Johnson)

The guide divides the original 37 species into categories, with a code for each bird to show. You’ll see below the codes relating to each of the 5 resident species:

  • Resident status – permanent / breeding, migratory or transient
  • Frequency – likelihood of seeing each species in its season, rated from 1 (very likely) to 5 (extreme rarities, maybe recorded once or twice since c1950
Bahama Warbler (endemic), Abaco Bahamas (Alex Hughes)

Bahama Warbler (endemic), Abaco Bahamas (Alex Hughes)

Numerically, the division of the 38 breaks down into 3 categories:

  • 5 permanent residents (PR) that breed on Abaco (B), of which two are ENDEMIC
  • 21 winter residents (WR) ranging from ‘everyday’ species to rarities like the rare, vulnerable Kirtland’s Warbler (now under threat from proposed development)
  • 12 transients, most of which you will be very lucky to encounter
Palm Warbler, Abaco Bahamas (Nina Henry)

Palm Warbler, Abaco Bahamas (Nina Henry)

The photos used in this series were almost all taken on Abaco / the Cays. There’ll be examples of the male of each warbler species, with some females for contrast. Where I have no Abaco / Baha images – especially with the transients – I have used other mainstream birding resources and Wiki. All due credits will be given at the foot of each post.

Bahama Yellowthroat, Abaco Bahamas (Gerlinde Taurer)

Bahama Yellowthroat, Abaco Bahamas (Gerlinde Taurer)

The warblers shown above are a mix of warbler species on Abaco: resident / endemic, winter migrants, and transient / vagrant. Time to take a look at the first category, the Bahamas-loving resident species that live and breed on Abaco

5 PERMANENT RESIDENTS

BAHAMA YELLOWTHROAT Geothlypis rostrata PR B 1  ENDEMIC

Bahama Yellowthroat (endemic), Abaco Bahamas (Gerlinde Taurer)

Bahama Yellowthroat (endemic), Abaco Bahamas (Gerlinde Taurer)

BAHAMA WARBLER Setophaga flavescens PR B 1 ENDEMIC

Bahama Warbler (endemic), Abaco Bahamas (Bruce Hallett)

Bahama Warbler (endemic), Abaco Bahamas (Bruce Hallett)

YELLOW WARBLER Setophaga petechia PR B 1 

Yellow Warbler, sunrise, Abaco Bahamas (Tom Sheley)

Yellow Warbler, sunrise, Abaco Bahamas (Tom Sheley)

OLIVE-CAPPED WARBLER Setophaga pityophila PR B 1 

Olive-capped Warbler, Abaco Bahamas (Bruce Hallett)

Olive-capped Warbler, Abaco Bahamas (Bruce Hallett)

PINE WARBLER Setophaga pinus PR B 1 

Pine Warbler, Abaco Bahamas (Tom Sheley)

Pine Warbler, Abaco Bahamas (Tom Sheley)

In Part 2: Winter migrants from common to rare

PHOTO CREDITS Tom Sheley (1, 9, 11); Chris Johnson (2, 3); Alex Hughes (4); Nina Henry (5); Gerlinde Taurer (6, 7); Bruce Hallett (8, 10); Photos mainly from the archive collected for“THE DELPHI CLUB GUIDE TO THE BIRDS OF ABACO” by Keith Salvesen

URCHIN RESEARCHIN’: SEA HEDGEHOGS OF THE REEF


Long-spined sea urchin Diadema antillarum (Melinda Rodgers / Dive Abaco)

URCHIN RESEARCHIN’: SEA HEDGEHOGS OF THE REEF

The long-spined sea urchin Diadema antillarum featured in this post is one of those creatures that handily offers its USP in its name, so you know what you are dealing with. Something prickly, for a start. These are creatures of the reef, and many places in the Caribbean and in the western Atlantic generally sustain healthy populations.

Long-spined sea urchin Diadema antillarum (Melinda Rodgers / Dive Abaco)

These animals are essentially herbivores, and their value to vulnerable coral reefs cannot be overstated. Where there is a healthy population of these urchins, the reef will be kept clean from smothering algae by their methodical grazing. They also eat sea grass.

Long-spined sea urchin Diadema antillarum (Melinda Rodgers / Dive Abaco)

HOW DO THE SPINES OF DIFFERENT KINDS OF URCHIN COMPARE?

Small sea urchins species have spines a few cms long at most. The long-spine variety exceed 10 cms, and the largest may have spines up to 30 cms (= 1 foot) long. The length, as shown here, means that when the creatures are safely lodged in crevices near their algae supply, their spines remain very visible.
Long-spined sea urchin Diadema antillarum (Melinda Riger / G B Scuba)
Anatomy of a long-spined sea urchin. You may possess a few of these organs yourself…

Long-spined sea urchin Diadema antillarum anatomy diagram (wiki)

Long-spined sea urchin Diadema antillarum (Melinda Rodgers / Dive Abaco)

CAN YOU GIVE US A TEST, PLEASE?

As with SAND DOLLARS and similar creatures, the skeleton of a sea urchin is known as a ‘test’. Urchin tests are remarkably beautiful, especially seen in sunlight. Here are 2 examples I photographed a while ago. You’ll immediately notice the delicate colours and the amazing complexity of the pattern and symmetry. The top one is (or is most like) a long-spined urchin test.
Long-spined sea urchin Test / Skeleton Diadema antillarum (Keith Salvesen / Rolling Harbour) Long-spined sea urchin Test / Skeleton Diadema antillarum (Keith Salvesen / Rolling Harbour)

A BIT ABOUT SYMMETRY

Sea urchins are born with bilateral symmetry – in effect, you could fold one in half. As they grow to adulthood, they retain symmetry but develop so-called ‘fivefold symmetry’, rather as if an orange contained 5 equal-sized segments. The graphic above gives a good idea of how the interior is arranged inside the segments.

Long-spined sea urchin Diadema antillarum (Melinda Rodgers / Dive Abaco)

A FEW FACTS TO HAND DOWN TO YOUR CHILDREN

  • Urchin fossil records date the species back to the Ordivician period, c 40m years ago
  • In the ’90s the population was decimated and still has not recovered fully
  • Urchins feel stress: a bad sign that the spines here are white rather than black
  • Urchins are not only warm water creatures: some kinds live in polar regions
  • Urchins are of particular use in scientific research, including genome studies
  • Some urchins end up in aquariums / aquaria, where I doubt the algae is so tasty
  • Kindest not to prod or tread on them
  • Their nearest relative (surprisingly) is said to be the Sea Cucumber 

Sea Cucumber (Melinda Riger / G B Scuba)

ARE THEY EDIBLE?

Apparently they are eaten in some parts of the world; their gonads and roe are considered a delicacy. As far as I know, they are not generally on the menu in the Bahamas. Correction invited. Personally, I could leave them or leave them.

CREDITS: Melinda Rodgers / Dive Abaco (1, 2, 3, 6, 9) taken Abaco; Melinda Riger / G B Scuba (4, 10, 11) taken Grand Bahama; Keith Salvesen / Rolling Harbour (7, 8) taken Abaco; Wiki graphic (5) taken from internet. RESEARCH Fred Riger for detailed  information; otherwise the usual magpie pickings…

Long-spined sea urchin Diadema antillarum (Melinda Riger / G B Scuba)

BLUE CHROMIS: A FLASH OF COLOUR ON THE REEF


BLUE CHROMIS: A FLASH OF COLOUR ON THE REEF

I’ve gone pictorial for today because I have only got my phone with me while we are away. Composition is slow, close to decomposition – and the comms connection is close to disconnection

Blue chromis (Chromis cyaneus) belong to the same group of fishes as damselfishes. These unmistakeable, bright reef denizens are very visible despite their tiny size. These fish are shoalers, so out on the reef you can enjoy them flickering around you as you swim along or hang in the water to admire the corals.

Like many a pretty and easily captured small fish that can be monetised once removed from its natural home environment, the blue chromis is popular for aquariums, and for humans to keep in their own home environments, unselfishly feeding them concocted food.

Blue chromis are adaptable and sociable, and will happily swim with other small reef fishes (as above). My own favourite combo is chromis mixed in with sergeant majors. But a shoal of them (mostly) alone is pretty special too….

I cynically mentioned ‘concocted’ food earlier. Here is one online care instruction for looking after them: “They are omnivores, meaning that they eat both meaty and plant based foods. They are not difficult to feed and will eat a variety of regular aquarium fare, frozen, live, and sometimes even dry food. Feeding them a variety of foods will help them retain their color in captivity. They sometimes feed on the algae in the tank”. 

If you are tempted to rescue some from their reef habitat, rest assured that: They have been known to spawn in captivity. Blue chromis can usually be obtained for about $10-15. And don’t hold back on the frozen food (though maybe warm it up a bit before feeding time).

Credits: Melinda Rodgers / Dive Abaco; Melinda Riger / G B Scuba

BAHAMAS REEF FISH (53): YELLOW GOATFISH


Goatfish, Bahamas (Melinda Riger / G B Scuba)

BAHAMAS REEF FISH (53): YELLOW GOATFISH

GOATFISHES belong to the mullet family, a large group of species with a flexible membership. In other words, there is disagreement as to whether certain fish are mullet or not. For present purposes, it’s not our problem – no one doubts that the goatfish is a mullet.

Goatfish, Bahamas (Melinda Riger / G B Scuba)

SO WHY ARE THESE CALLED GOATFISH? WAS SOMEONE KIDDING?

These fish get their name for the pair of so-called ‘barbels’ below their mouths (see image below), thought to be reminiscent of a goatee beard. The name has Latin origin, ‘barbula‘, meaning a small beard. Linnaeus may have had a hand in this choice of description.

Goatfish, Bahamas (Melinda Riger / G B Scuba)

WHAT IS THE FUNCTION OF THE BARBELS?

The barbels are sensory organs which, depending on the creature, may be located on either side of the mouth, on the chin, or even extending from the nostrils. In broad terms, the barbels are where the taste buds are located. They help a fish to find food even when the water is stirred up or murky or at night, and are used to probe into sand or into holes in the reef for prey.  

Goatfish, Bahamas (Melinda Riger / G B Scuba)

WHY ARE THEY OFTEN SEEN WITH YELLOWTAIL SNAPPERS, GRUNTS & PORKFISH?

Goatfish have limited means of self-protection. They are not poisonous or venomous, they have no spines or razor-sharp teeth, nor ink to squirt. They do have an ability to change colour rapidly to blend into their surroundings – e.g. over pale sand – to make them less conspicuous to predators. Overall, however, they are docile and probably delicious to many other species. Their bright hues may have some function as aposematic colouring to warn, scare or repel potential predators, but this is possibly of limited use among the familiar reef denizens. So instead the goatfish goes in for so-called protective mimicry, as shown in the image above.

Goatfish, Bahamas (Melinda Riger / G B Scuba)

PROTECTIVE MIMICRY?

Goatfish and yellowtail snappers (in particular) are similar in size, appearance, coloration and behaviours, though the feeding patterns differ. The reason they are often found in mixed groups on the reef is for the individual protection they gain in a larger mixed school. This really amounts to taking advantage of safety in numbers (especially for the fishes in the middle). Here’s a very recent photo that shows exactly this scenario – a large mixed shoal of two almost indistinguishable fish species.

Goatfish & Yellowtail Snappers shoaling (Melinda Riger, GB Scuba)

IS THIS A ‘SPOT THE DIFFERENCE’ TEST?

If you’d like to make it so! (click on the image to enlarge it). Look out for the fish with the barbels (Goatfish); and the fish with the larger, more deeply forked tails (Snappers). A predator won’t take a great deal of notice of the finer points of difference of course, but overall this large mixed shoal gives a degree of protection to individual fish in the unit as a whole

Goatfish, Bahamas (Melinda Riger / G B Scuba)

ARE GOATFISH EDIBLE?

Goatfish are eaten in many ares of the world, though I can’t recall seeing it on a Bahamian menu. The Romans ate the local mullet / goatfish species, but then they ate many things that we do not now consider as permissible food – dormice in honey for example. Rather revoltingly, the goatfish were served live so that guests could watch them die and see the amazing change of colours in the process. Barbaric? But don’t we cook live… well, never mind that.

Goatfish, Bahamas (Melinda Riger / G B Scuba)

Photos: all great photos from Melinda Riger / Grand Bahama Scuba; magpie research pickings inc. the abstract of a scientific paper with about 23 authors; tip ‘o the hat to Wiki, no seriously

Goatfish, Bahamas (Melinda Riger / G B Scuba)

WAVE CHASERS: SANDERLING POOL TIME ON ABACO


Sanderling, Delphi Beach Abaco Bahamas (Keith Salvesen / Rolling Harbour)

WAVE CHASERS: SANDERLING POOL TIME ON ABACO

It’s often a hard decision whether to include a short piece of video footage in a post. By short, I mean less than a minute. On the one hand, there is usually a good reason for inclusion, even if only aesthetic. On the other, it simply takes up more time for busy people who may prefer to flick through an article and enjoy some nice images along the way. Today, you can have the best of both worlds.

Sanderling, Delphi Beach Abaco Bahamas (Keith Salvesen / Rolling Harbour)

Sanderlings are definitively ‘peeps’, a group name that embraces the smallest and squeakiest sandpiper species. They are the wave chasers, the tiny birds that scuttle along the beach, into the retreating tide for a snack from the sand, and back to the beach again as the waves creep in. Their little legs and feet move in a blur, and many people immediately think of wind-up clockwork toys as they watch the birds in action.

Sanderling, Delphi Beach Abaco Bahamas (Keith Salvesen / Rolling Harbour)

One of the joys of being a sanderling is that rock pools fill and empty diurnally. At some time during daylight, there’s the certainty of a quick dip. I was lying on the beach when I took this short video, so that I didn’t spook the birds. I was equipped with a smallish camera (I drowned it the following day. By mistake I mean) but I kept my distance rather than try to get closer and spoil their joyful bathing.

I caught these little birds at a critical moment. You can tell that the tide is coming in fast. The peeps are becoming edgy, and weighing up the joys of immersion in a pool with the less enjoyable prospect of being washed out of the pool by the next wave. Within a minute or so, they had all flocked down the shoreline for a foraging session.

Waves and incoming tide getting a little too close for comfort on the edge of the pool…Sanderling, Delphi Beach Abaco Bahamas (Keith Salvesen / Rolling Harbour)

Next to the migratory PIPING PLOVERS that favour Abaco as their winter home, the wave chasers are my favourite shorebirds. My keenness on them killed my camera. I went out into the incoming waves to get shots back at the beach with the sun behind me. Great idea until I lost my balance with, as they say, hilarious consequences. Lesson learnt – never turn your back on waves.

Sanderling, Delphi Beach Abaco Bahamas (Keith Salvesen / Rolling Harbour)

All photos © Keith Salvesen / Rolling Harbour taken on the beach at Delphi, Abaco, Bahamas

Sanderling, Delphi Beach Abaco Bahamas (Keith Salvesen / Rolling Harbour)

SPIDER WASPS & TARANTULA HAWKS: STEP AWAY FROM THIS INSECT


Spider Wasp / Pepsis Wasp / Tarantula Hawk Abaco Bahama (Keith Salvesen / Rolling Harbour)

SPIDER WASPS  & TARANTULA HAWKS (PEPSIS WASPS)

I’ve recently had a flood of online hits for a creature I wrote about several years ago. It’s an aggressive-looking insect that I found in the coppice on South Abaco. I have revisited and revised the original article, with some better images than my own original ones. I could only get a partial shot of the insect, and I wondered whether to try to reach it and get a more complete shot. Perhaps I could have, but very fortunately for for me (as it later turned out) I didn’t touch it.

Spider Wasp / Pepsis Wasp / Tarantula Hawk Abaco Bahama (Keith Salvesen / Rolling Harbour)

This creature turned out to be a Spider Wasp (aka Pepsis Wasp), of the Pompilidae family. The insect is familiarly known as a Tarantula Hawk, for reasons give in unsparing detail below. For it turns out that this creature would be the hardest bastard insect on Planet Bastard in the Galaxy Bastardium. 

Spider Wasp / Pepsis Wasp / Tarantula Hawk - TheCrotalusfreak

It’s lucky that I didn’t try to try to collect it to keep it in a matchbox (if those even exist now).  Note, for start, the scary eating apparatus… and it’s not for nibbling leaves as I had thought, but chopping up small insects. The leg claws and barbs are for pinning down its prey. You would not believe how unpleasant these little buddies are –  and that’s before we even mention the sting…

SPIDER WASPS IN ACTION

These wasps are known in some countries as “horse-killers”. There are many species around the world, with 6 subspecies, one of which being the Tarantula Hawk or Pepsis Wasp – so-called because it hunts tarantulas and uses them in a most ingenious and cruel way… NB the BNT have rightly pointed out that these insects are unaggressive to humans. If you leave them alone, they will spare you. I’ve also read that “The tarantula hawk is relatively docile and rarely stings without provocation” Now read on to see if it might be sensible to provoke one or not.

Spider Wasp / Pepsis Wasp / Tarantula Hawk - astrobradley

SCARY CRITTERS & LIVING LARDERS

(Trigger Warning: this is really rather gross)

SPIDER WASPS are ‘solitary’ insects that feed on ground spiders/ tarantulas by stinging them to paralyse them, then eating them. In the most sinister way, the females also make use of spiders for breeding purposes. Hear this! They build a nest in a burrow, find a spider (a tarantula for choice), paralyse it with their sting, drag it to the nest and lay a single egg on its abdomen. Then they seal up the burrow. 

Spider Wasp / Pepsis Wasp / Tarantula Hawk mshandro

When the egg hatches, the larva chews a hole on the spider’s abdomen and enters a living larder. It gradually eat its host as it grows. The spider’s vital organs are left till last, so that the spider stays alive as long as possible until the larva has reached full-size. After several weeks, the larva spins a cocoon and pupates (often over winter). Finally, the wasp becomes an adult, bursts Alien-like from the spider’s abdomen (deftly evading Ripley), and tunnels out of the burrow… 

Do NOT try this at home or more than 10 yards from a medical centre Spider Wasp / Pepsis Wasp / Tarantula Hawk _ Paul Nylander

SPIDER WASPS: MORE FEARFUL FACTS

  • Their hunting improves with experience – the more spiders they eat, the quicker they find, attack & kill them
  • Males use ‘perch territories’ to scan for receptive females from a tall plant or other vantage point, a behaviour known as HILL-TOPPING
  • Adult wasps also feed on a variety of plants for nectar & pollen. They may become intoxicated on fermented fruit, which affects their ability to get around (I think we’ve all been there at some time…)
  • The female Pepsis gets her spider in two main ways: approaching a tarantula causing it to rear up defensively on its legs, thus exposing its abdomen to the sting or
  • She locates a tarantula’s burrow, using her sense of smell. She tricks the spider into emerging by tweaking the web at the burrow’s entrance or ‘intruding’ (see video below)
  • The wasp uses her long stinger to stab her prey. The poison rapidly paralyses the spider. She then drags it to her burrow, lays her egg onto the tarantula’s abdomen, seals the burrow and leaves. Job done
  • The hooked claws and barbs on the wasps’ long legs are weapons for grappling with victims
  • The stinger of a female tarantula hawk can be up to 7 mm (1/3 inch) long – and the sting is among the most painful insect stings in the world (see below)
  • Only the females sting (males may pretend to) because the stinger is linked to the ovipositor (egg-laying organ)
  • You can distinguish females from males by the curled antennae of the female. Mine was therefore female
  • The Pepsis wasp has (unsurprisingly) very few predators, though apparently roadrunners and bullfrogs may tackle them

Here is a hypnotically fascinating 3-minute video of the life-or-death struggle

SPIDER WASP  –v-  TARANTULA 

THE STING

The sting of these wasps is among the most painful of any insect, though the most intense pain lasts on a few minutes. Entomologist Justin Schmidt bravely submitted himself to the stings of various insects and described this pain as “…immediate, excruciating pain that simply shuts down one’s ability to do anything, except, perhaps, scream. Mental discipline simply does not work in these situations.” 

Schmidt produced his SCHMIDT STING PAIN INDEX The pain scale, based on 78 species, runs from 0 to 4, with 4 awarded for the most intense pain. Spider Wasps of the species Pepsis – i.e. Tarantula Hawks – have a sting rating of 4.0, described as “blinding, fierce, shockingly electric. A running hair drier has been dropped into your bubble bath” Only the bite of the Bullet Ant – and the sting of the Warrior Wasp – is ranked higher, with a 4.0+ rating, vividly described as pure, intense, brilliant pain. Like fire-walking over flaming charcoal with a 3-inch rusty nail in your heel”

LIGHT RELIEF AFTER THE PAIN

1. In 1989, New Mexico chose the Tarantula hawk wasp as the official state insect. The choice seems to have been left to schoolchildren and I’m guessing here (or gender-stereotyping) but I suspect it was the boys’ choice that won…

2. Tarantula Hawk is a “psychedelic progressive metal band” from San Diego, Ca. Their short discography includes their debut Tarantula Hawk (CD/LP, 1998); Burrow (Live CD, 2000, self-released); and Untitled. The cover of their debut provides the perfect ending for this post, vividly depicting the colour and texture of the swirling fiery pain you could experience (and I don’t really mean from listening to the music…) 

UNDOUBTEDLY PAINFUL EXPERIENCE

ARGUABLY PAINFUL STING

Mr Gordon Sumner

AN ENJOYABLE STING

Credits:  Keith Salvesen / Rolling Harbour (1, 2, 7); TheCrotalusfreak (video clip) (3);  astrobradley (4);  mshandro (5); Paul Nylander (6)


Spider Wasp / Pepsis Wasp / Tarantula Hawk Abaco Bahama (Keith Salvesen / Rolling Harbour)

PEACOCK FLOUNDERS REVISITED: NOW YOU SEE THEM…


Peacock Flounder (Melinda Riger / G B Scuba)

        PEACOCK FLOUNDERS (Part Deux)

MASTERS OF SUBAQUATIC CAMOUFLAGE

I featured the extraordinary, colour-transforming PEACOCK FLOUNDER Bothus lunatus about 3 years ago in the Bahamas Reef Fish series (No. 21 I think). These really are remarkable creatures, and I am pleased to be able to show some more wonderful illustrative photos. 

Peacock Flounder (Melinda Riger / G B Scuba)

ROVING EYES

In the fish shown here, you’ll see that – surprisingly – both eyes are on the upperside of the fish, above the rather grumpy mouth, whereas the head is horizontal to the ocean floor. Oddest of all, juveniles are constructed conventionally with bilateral eyes, and look like ‘normal’ fish rather than flatfish.

Peacock Flounder (Melinda Rogers / Dive Abaco)

As the fish matures, in some magic way the mechanics of which I can only guess at**, the right eye grows round to the topside and the flounder transforms from a ‘vertical’ fish to a flatfish. For this reason, the PF is known as a ‘lefteye’ flounder. Maybe in other flounder species in the world – the southern hemisphere maybe? – the eye that moves round to the upperside is the left eye.

Peacock Flounder (Virginia Cooper / G B Scuba)

The eyes of this fish have another special trick up their sleeves (so to speak). They operate completely independently. Thus the creature can look left and right, or forwards and backwards, simultaneously. It’s an excellent system for detecting predators coming from any angle. It’s a superpower we might all benefit from.

Peacock Flounder (Melinda Rogers / Dive Abaco)

DO THEY HAVE ANY OTHER TRICKS WE SHOULD KNOW ABOUT?

Yes they do indeed. If you have been admiring the fish shown so far, you’ll have noticed that the colour of each one differs from the others. In addition to the predator-protection that the eyes provide, the peacock flounder can make itself (near) invisible. They can rapidly change colour to match their surroundings. There are 3 reasons for this: to avoid / confuse predators; to conceal themselves on the sea-floor to catch passing prey; and, as dive expert Fred Riger has pointed out, “the male peacock flounder can, and does greatly intensify his colours to declare territory and attract females. When doing this the males will also signal with the left pectoral fin, sticking it straight up and waving it around.” 

The same fish, photographed over several minutes as it moves over the ocean floorPeacock Flounder (Wiki)

Matching the background happens as the fish swims, and in a few seconds. When they rest on the sea-floor, the camouflage may even become total. In #4 above you can just about make out the eyes. The whole effect is known as ‘cryptic coloration’ or CRYPSIS. In contrast, the image below shows just how adaptable the transformation can be. Note how the fish can even mimic the pinkish tinge of the sand perfectly. If threatened, the fish will bury itself in the sand, with just its eyes showing.

Peacock Flounder (Melinda Rogers / Dive Abaco)

HOW DO THEY MANAGE TO CHANGE COLOUR IN SECONDS?

It’s complicated! A simple answer is: a mix of hormones, pigment-cells and vision, all coordinating rapidly. The colour change works in two ways: pigments are selectively released to the skin cells; and other pignments can be selectively suppressed. An analogy might be image manipulation using variations in brightness, saturation etc. Not convinced? Then watch this short video and prepare to be impressed. Astonished, even.

WHAT IF A FLOUNDER CAN’T SEE CLEARLY FOR SOME REASON?

As with many (all?) superpowers, there is usually some kryptonite-style flaw. A flounder with a damaged eye, or one temporarily covered (by sand, for example) will have difficulty in changing colour – possibly at all, or at any rate with the swiftness it needs to have. 

Peacock Flounder (Melinda Riger / G B Scuba)

THESE SIDEWAYS FISH – HOW DO THEY… YOU KNOW…?

Take a look at the fish above with its top fin raised. It’s a ‘ready’ signal in a harem. Male flounders have a defined and defended territory within which live up to 6 females – a so-called ‘harem.’ I can do no better than borrow the description of the rituals from an article derived from scientific papers by Konstantinou, 1994Miller, et al., 1991 in the website animaldiversity.org/…ounts/Bothus_lunatus To which I can only add, ’15 seconds, eh?’

Peacock Flounder (Melinda Riger / G B Scuba)

“Mating activities usually begin just before dusk. At this time, a male and a female approach each other with the ocular pectoral fin erect. The two fish arch their backs and touch snouts. After this interaction the female swims away, and the male sometimes follows, approaching the female again from the left side. At this point the male pectoral fin is erect and the female pectoral fin moves up and down, possibly signalling willingness to mate. The male then positions himself underneath the female and mating begins. This process consists of a mating rise, during which the female and male rise in the water column together. On average, these rises last about 15 seconds. At the highest point of this rise, usually around 2 m above the substrate, gametes from both fish are simultaneously released, producing a cloud of sperm and eggs. Once the couple returns from the rise, the male “checks” to make sure mating was successful, and the pair separates quickly, swimming away from each other in opposite directions. Not all mating rises are successful, and the process of “checking” is thus important. The exact purpose of the mating rise in these flounders unknown; possible reasons for rising include better dispersal of gametes and predator avoidance.” 

Peacock Flounder – Kim Rody ArtPeacock Flounder (Kim Rody Art))

**This may in fact be through sheer laziness

Credits: Melinda Riger & Virginia Cooper / Grand Bahama Scuba; Melinda Rogers / Dive Abaco; Adam Rees / Scuba Works; Kim Rody; animaldiversity.org; magpie pickings and other credits in the text

Peacock Flounder (Melinda Riger / G B Scuba)