SHARKS! APEX PREDATORS IN THE BAHAMAS


Sharks in the Bahamas (Melinda Riger / Grand Bahama Scuba)

SHARKS! APEX PREDATORS IN THE BAHAMAS

Immersion in current affairs these days brings inevitable acquaintance with sharks of various kinds, and all best avoided. Let’s have a look the real thing, the apex marine predators that in the Bahamas are all around you once you leave the safety of the shore. I haven’t featured them for ages, and it’s always a pleasure – a slight thrill, even.

Sharks in the Bahamas (Melinda Riger / Grand Bahama Scuba)Sharks in the Bahamas (Melinda Riger / Grand Bahama Scuba)

I don’t do scuba, indeed my swimming would easily be outclassed by a competent four-year old. But I see these creatures when I’m out fishing; or as they hang in the breaking waves off the Delphi beach, watching intently for a meal.

Sharks in the Bahamas (Melinda Riger / Grand Bahama Scuba)

We watch them (and stingrays) from the balcony as they lazily make their way round the margins of the wide bay, from little ‘uns to (recently) a huge bull shark. We watch as, when someone is in the water, they change course slightly to pass by them. So far, anyway…

Feeding sharksSharks feeding in the Bahamas (Melinda Riger / Grand Bahama Scuba)

The one that got away… (a sad sight)Sharks in the Bahamas (Melinda Riger / Grand Bahama Scuba)

I once took a rather primitive underwater camera with me while snorkelling in Fowl Cays National Park. This was several years ago, when I believed a cheap 2mb camera might turn me into one of the Blue Planet team. I was wrong. The shark I saw, apparently some 20 miles away (when I examined the image) – well, that’s its tail, top left…

Sharks in the Bahamas (Melinda Riger / Grand Bahama Scuba)Sharks in the Bahamas (Melinda Riger / Grand Bahama Scuba)

Just to look at these images is to understand that when you are in the sea, you are in the sharks’ environment. They are the masters of it. They have their rules, and they are not much interested in you… unless you break them. Or so the theory goes.

Sharks in the Bahamas (Melinda Riger / Grand Bahama Scuba)Sharks in the Bahamas (Melinda Riger / Grand Bahama Scuba)

This fine shark below exemplifies the power and the menace of the shark. A creature to be admired, but also to be respected.

Sharks in the Bahamas (Melinda Riger / Grand Bahama Scuba)

All fantastic photos: Melinda Riger / Grand Bahama Scuba

SPERM WHALES – BMMRO FIELD TRIP, BAHAMAS


Sperm Whales, Bahamas (BMMRO)

SPERM WHALES – BMMRO FIELD TRIP, BAHAMAS

I can never quite get my head around the fact that the waters around Abaco are home to the twin leviathans, sperm whales and humpback whales. And before anyone points it out, I realise they can’t actually be twins: sperms whales (cachelots) are TOOTHED WHALES whereas humpback whales are BALEEN WHALES

Sperm Whales, Bahamas (BMMRO)

During November, the Bahamas Marine Mammal Research Organisation (BMMRO) undertook a rather special field trip. Using sophisticated devices, the scientists first located a group of sperm whales, and then tracked them through the night using the communications between the creatures – ‘vocalisations’ – to follow them. Later analysis of the recordings will have made it possible to identify the individuals through their unique vocal patterns – and so to recognise them again. 

Sperm Whale, Bahamas (BMMRO)

The hydrophonic equipment used is extremely sensitive, and can pick up the sounds made by whales and dolphins over a great distance. The box of tricks looks deceptively modest – I took these photos on a previous trip when we were looking for beaked whales and dolphins. Charlotte Dunn holds the microphone submerged on a cable and underwater sounds are amplified so that the slightest chirrup of a dolphin can be heard by everyone on the vessel. The sounds are recorded and locations carefully logged.

Besides the sperm whales, the BMMRO team also had sightings of spotted dolphins, bottlenose dolphins and beaked whales during the field trip. These bonus sightings will also have been logged for future reference. It all adds to the detailed research data that assists the conservation of the prolific marine mammal life in Bahamian waters.

Atlantic Spotted DolphinsAtlantic Spotted Dolphins, Bahamas (BMMRO)

By the time one of the whales decided to breach, it was some distance away, so I’m afraid I can’t bring you a dramatic close-up from the trip. But just to see this view at all is breathtaking.

All photos BMMRO except the 2 hydrophone ones on the research boat (Keith Salvesen)

ATLANTIC SPOTTED DOLPHINS OFF ROCKY POINT, ABACO


Atlantic Spotted Dolphins off Rocky Point, Abaco

This pair was in a group of 8 Atlantic Spotted Dolphins that we encountered yesterday during a day’s expedition on the Bahamas Marine Mammal Research Organisation (BMMRO) research boat. We spent nearly an hour with them, and there will be a longer post about these magnificent creatures in due course. But right now, I’m still in single image posting mode while “on-island”…

Photo: Keith Salvesen / BMMRO

SEAHORSES: PREHENSILE TALES FROM THE REEF


Seahorse (Adam Rees / Scuba Works)

SEAHORSES: PREHENSILE TALES FROM THE REEF

It’s a year since I last posted about these amazing little creatures, seahorses. I featured a number of photos by Melinda Riger, a couple of videos, some useful facts about them, and for some reason some useless facts that I came across in researching the post. You can chase it down here: SEAHORSES 1

Adam Rees of SCUBA WORKS is another diver, like Melinda, who combines great underwater experience with wonderful photographic skills. This posts showcases some of Adam’s seahorse photography, and if it doesn’t want to make you explore the reefs, I can’t think what will…

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

Seahorse Range MapMap: Seahorse range (Nat Geo)

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

shlifecycle-e1313548153493

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

Seahorse by Alex Konahin

All phantastic photos: Adam Rees / Scuba Works; Range Map, Nat Geo; Lifecycle diagram, Seahorserun; Seahorse GIF, Alex Konahin

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

 

A VISIT TO BIMINI’S MARINE ENVIRONMENT (1)


Loggerhead Hatchling Bimini BMPAC

Loggerhead Hatchling (Bimini’s Marine Protected Area Campaign)

A VISIT TO BIMINI’S MARINE ENVIRONMENT (1)

Abaco is fortunate already to have special conservation areas, both on land (e.g. the huge National Park) and at sea (e.g. Fowl Cay Marine Preserve). Other preserves are in active stages of development. Elsewhere in the Bahamas, where the natural life is equally wonderful, battles are being fought to protect pristine habitat from the encroachments of modern life such as unsuitable development (or development in unsuitable locations). For this first look at Bimini, I am most grateful to Bimini’s Marine Protected Area Campaign  for permission to use some of their wonderful photographic archive that illustrates the vital importance of the mangroves, reefs, sea grass and pristine sea to marine life large and small. It’s worth checking out the background and surrounding context of these images to see the sort of habitat the creatures depicted prefer. This post features some of the larger species.

HAMMERHEAD SHARKS

Hammerhead Shark, Bimini (Grant Johnson/ 60 Pound Bullet)Hammerhead Sharks 3 Bimini's Marine Protected Area Campaign Hammerhead Shark 2 Bimini's Marine Protected Area Campaign Hammerhead Shark 4 Bimini's Marine Protected Area Campaign

NURSE SHARK NURSERY IN THE MANGROVES

Nurse Sharks Bimini's Marine Protected Area Campaign Nurse Shark BMPAC

BOTTLENOSE DOLPHINS

Dolphin 2 Bimini's Marine Protected Area CampaignDolphin Bimini's Marine Protected Area Campaign

RAYS

A pregnant female southern stingray, seen from belowSouthern Stingray (pregnant) Bimini's Marine Protected Area CampaignRay, Bimini's Marine Protected Area Campaign Ray, Bimini's Marine Protected Area Campaign

HAWKSBILL TURTLES

Turtle in Mangroves Bimini's Marine Protected Area CampaignHawkshead Turtle 2 Bimini's Marine Protected Area Campaign

CREDITS: Bimini’s Marine Protected Area Campaign with many thanks for use permission of their material including images © Grant Jonson / 60 Pound Bullet Photography, and to all other photographers featured. Overall, cheers to Bimini, wildlife and conservation…

“ALIEN FROM THE DEEP”: ABACO’S SCALELESS BLACK DRAGONFISH


Scaleless Black Dragonfish - Header - BMMRO Abaco

“ALIEN FROM THE DEEP”: ABACO’S SCALELESS BLACK DRAGONFISH

Prepared to be terrified. Beneath the placid turquoise waters of Abaco lurks a ruthless and implacable killer of hideous mien, armed with vicious teeth  … Yes, as the music from Jaws begins to throb round your temples I bring you… THE SCALELESS BLACK DRAGONFISH, aka the Deep Sea Dragonfish or Viperfish (of which it is one type). Oh, and it’s about 8 inches/ 20 cms long.

The specimen shown here was found off Rocky Point, Abaco during a whale and dolphin research trip by the BMMRO. This is an area where typical low waters give way to the far deeper waters of an arm of the Great Bahama Canyon. It is an excellent place for whale watching, since one effect of the canyon is to provide plentiful food of the sort that cetaceans thrive on. The chances of you ever meeting a dragonfish are very slim indeed, since they live at depths up to 1500 metres. 

MAP to be added after posting, to avoid FB’s deranged random ‘feature photo’ selection The black star at the south end of Abaco  (in the yellowish box) is where Rocky Point and Sandy Point are to be found.

BAHAMAS SEA DEPTH MAP (NEAQ)

Here is an account by BMMRO intern Luanettee Colebrooke who was lucky enough to be on the research vessel when this strange, vicious-looking creature was found. I have edited the material for present purposes, but I recommend reading the whole article which can be found on the BMMRO website HERE. You will get an excellent overview of a day’s research under the hot sun, and plenty about the collection of whale poop (a topic I have previously dwelt on HERE (“Familiar Feces“).

Scaleless Black Dragonfish - BMMRO Abaco
CREATURE by Luanettee’ Colebrooke, BMMRO intern, summer 2014
The crossing of this organism was by complete accident. It was something that none of us would have imagined finding floating along the surface of the water. For Dr Claridge, Jurique (another BMMRO summer intern from Cat Island) and I as Bahamians, who knew this creature even existed in our majestic waters? Who knew our waters were even that deep to hide this specimen? (I think Dr Claridge knew)
Our morning began as per the usual routine for a boat day. There are several research sites that we venture to regularly: Rocky Point for the coastal Bottlenose Dolphins, and an area about 2 miles south of Rocky Point for our very elusive and wary Blainville’s beaked whales, and the deep blue (a massive drop into waters that are 1500 metres deep) to listen for Sperm Whales.It is not that I do not believe that we have deep waters. The Tongue of the Ocean runs through the northern part of our country. My thought comes more from, ‘our waters are that deep’? To a point where light does not hit the bottom and organisms have to rely mainly on bioluminescence? It is a similar thought process I had when I saw a sperm whale for the first time. They are not small creatures of the sea. It is both an awe and scary thought that there are creatures out there we, as Bahamians, do not know exist in our waters.
Scaleless Black Dragonfish - BMMRO AbacoScaleless Black Dragonfish - BMMRO Abaco
“Our final activity of the day was tracking a sperm whale acoustically using a hydrophone…” There follows a graphic account of the technicalities of sperm whale poop collection and co-intern Jack’s “Faecal Dispersion Technique”. Then this: Jack stood up, Pringle in mouth and pointed to a black leather looking strap off of the port bow. “What is it?” Moving closer to the port, Jurique and I had our own thoughts. “It looks like a boxing glove strap,” he suggested. “More like an expensive underwater watch,” I mentioned. Dr. Claridge said, “It looks like a squid tentacle.” Jack added in, “More like the strap from a fin to me.” Our heads were turning with no closer answer. Taking it upon himself as the official sample collector, Jack popped back into the water to collect it. There were no sample pots large enough for it, so he had to use a large Ziplock bag to pick it up.
Scaleless Black Dragonfish - BMMRO AbacoLetting out a surprised chorus when he got back on the boat, we wondered what the heck it was. It had a mouth and a weird white patch that at first, I thought was its eye. The ventral abdominal section seemed swollen as if it had expanded from the decreasing pressure rising from the sea. As we looked at it and took photos, we determined several characteristics of the deceased specimen without having to autopsy it. The first was that it had three rows of needle like teeth that turned inward. There was what we assumed to be an angler under its ‘chin’ that had a murky transparent color. Another deduction we came to was the white dots that ran along the body all the way to its tail could be bioluminescent in nature like an angler. The pectoral fins were small and thin like a tooth pick. The final detail we took note of was the silver patch underneath its eyes.It was a type of angler fish we hypothesized. And it somehow ended up on the surface. There were several questions we voiced to each other: if it is a deep angler fish, how did it end up here? Where did it come from? Was it stunned by the sperm whale’s echolocation and pulled upwards as it surfaced? Later that night as we went through our faecal samples, photo IDs and data entry, the search began for what exactly this organism was. Jack did some image trickery and overlapped the photos with an alien from Alien. Scaleless Black Dragonfish c/w Alien - BMMRO AbacoI personally thought it looked more like Venom from Spiderman. As he did that, I took it upon myself to begin the search by looking up the most prominent feature: the angler on the anterior ventral side of the fish. By using this characteristic, I was able to narrow the organism down to a Scaleless Black Dragonfish by using several online scientific key identification guides and forums. The species we are still unsure about. The mystery continues…Scaleless Black Dragonfish - BMMRO Abaco
This creature is one of a number of dragonfish species found worldwide. This one might to be one of the genus Melanostomias (says he, hesitantly…). Like many deep sea creatures, its customary depths are pitch black, or nearly so; and so it is equipped with its own light source (bioluminescence), including the item dangling down from its lower jaw, called a barbel. The fish’s glow and no doubt the gleam of the barbel swaying around in the water act as a lure to attract prey that swim up to investigate and then.. snap! Those teeth start to do their work.
Scaleless black dragonfish (Melanostomias biseriatus) (imagesource.com)
I’ll end with an amazing short (2:28) video posted in early 2014 by ‘Indoona’. The accompanying description is the most authoritative account of the species and its little ways that I have  come across, complete with useful links. I include it before the video, noting only that the creature featured is a Pacific one from off the coast of California, and therefore not identical to the Abaco one.
                                                                       scaleless-black-dragonfish-mini-jpg          scaleless-black-dragonfish-mini-jpg          scaleless-black-dragonfish-mini-jpg

THE DEEP SEA DRAGONFISH OR VIPER FISH is an awesome looking creature from the middle depths of the ocean (this one comes from 600 metres or about 1000 feet deep). Also called the scaleless dragonfish, they are ferocious predators, with extremely large teeth compared to their body size. And they have one of nature’s most amazing tricks to give them the edge over their prey (more below).

There are several different species of dragonfish (one estimate is 67 species – all from the fish family known as Family Stomidae) and they are quite difficult to tell apart but this one is from the pacific depths of California and is likely Tactostoma macropus, the longfin dragonfish. Idiacanthus antrostomus is an Atlantic species that looks very similar – at least I think that’s the case correct me if I’m wrong.

They hunt with a bioluminescent barbel or lure. It is not glowing here but under the different lighting regimes I used – some of the darker images – you can see how much the lure stands out.

Sadly fish like this do not survive long on the surface, mainly because of temperature differences and mechanical damage in the net rather than pressure problems I think. It was caught in a cod-end trawl and filmed in a special tank (a kreisal aquarium). But is great to be able to share another wonder of the oceans on YouTube.

And their amazing trick? Unlike most other deep sea creatures which are sensitive to blue light – the dragonfish also produces a red light beam (see the organ to the rear of the eye) – it is also very sensitive to red light. Although red light does not travel very far underwater it allows them to see when other animals cannot and to sneak up on their prey – especially shrimps that glow in the red light. For more detail see: http://www.science-frontiers.com/sf10… and the work of Ron Douglas and Julian Partridge,http://blog.wellcomecollection.org/ta… (these images were filmed with the help of Julian and Ron). Oh and this dragon is not big – about 20 cm or just under a foot!

[youtube https://www.youtube.com/watch?v=i6cIoj7c2FI]

Credits: Luanettee Colebrooke, ‘Jack’ & BMMRO (to whom thanks as ever), imagesource.com, Indoona , and 2 sites I came across during my investigations – seasky.org & strangesounds.org

If you can’t get enough of dragonfish, check out this Tumblr site for dozens of images including photos, drawings, cartoons, and enough strange dragonfish-based characters to weird you out utterly… HERE

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