THE BAHAMAS: A STAMPING GROUND FOR DOLPHINS


Dolphin leaping, Abaco (BMMRO)

THE BAHAMAS: A STAMPING GROUND FOR DOLPHINS

I have commented before on the excellent wildlife stamps produced by the Bahamas Philatelic Bureau, and there is a fairly comprehensive page featuring many of the special issues HERE. Recently, dolphins were treated to their own set of stamps, in conjunction with the BMMRO (Bahamas Marine Mammal Research Organisation).  Four dolphin species are showcased, with a fifth species (Risso’s Dolphin) shown on the commemorative Official First Day Cover (replete with the BMMRO logo). The release date was 31 March 2016.

Bahamas Dolphin Stamps 2016

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The stamps are available as sets of 4 or of course individually. In a newsletter earlier this year, the BMMRO included some fascinating information about their valuable work – in particular with whales – and about the individual dolphin species featured in this very special philatelic issue. This was also published by the stamp producers, Pobjoy Mint Stamp Division.

BMMRO is a Bahamian non-profit organisation whose mission is to promote the conservation of marine mammals in The Bahamas through scientific research and educational outreach. Since 1991, BMMRO has been conducting small vessel surveys primarily around Abaco Island to document the occurrence, distribution and abundance of marine mammals in The Bahamas.

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BOTTLENOSE DOLPHINS Tursiops truncatus

These are the most common marine mammals seen on the Bahama banks. It should be noted, however, that there are at least two distinct “breeding populations” or “ecotypes” of this species: coastal bottlenose dolphins that inhabit the shallow waters of the banks; and oceanic bottlenose dolphins found in pelagic waters. These populations diverged genetically several hundred thousand years ago and have since developed different physiological adaptations to their respective marine environments. The coastal ecotype is smaller in length reaching just over 8 feet and has a relatively larger dorsal fin and pectoral fins which helps them to maneuver more readily around rocks and reefs to catch fish, and to regulate their internal body temperature (the temperature of the shallow Bank waters fluctuates much more than the deeper Atlantic Ocean). The coastal dolphins do not travel much beyond the bank edge and live in small resident communities. The deeper diving oceanic ecotype can reach 10 feet or more in length, are usually seen in larger groups and appear to have a more extensive range with movements documented between Abaco, Bimini and Exuma Sound.

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ATLANTIC SPOTTED DOLPHINS Stenella frontalis

These dolphins are not born with spots, but actually accumulate them as they mature, becoming quite mottled-looking as adults. Hence, young spotted dolphins are often confused with bottlenose dolphins, and sometimes the two species will interact, which adds to the confusion. Although they can reach almost the same length as bottlenose dolphins, they have a smaller girth and thus body weight. Atlantic spotted dolphins are a year-round resident species in The Bahamas. Individuals photo-identified 20 years ago in Abaco can still be seen in the same areas today. They are commonly seen in groups of 20-50 dolphins in the oceanic waters where they feed on flying fish and squid, and rarely venture on to the bank. However, along the western edges of Little and Great Bahama Banks this species can regularly be found on the bank during the daytime where they come to rest and socialise.

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PANTROPICAL SPOTTED DOLPHINS Stenella attenuata

This species is more slender in body shape than Atlantic spotted dolphins, and also have a distinctive dark dorsal cape, which sweeps from their rostrum to behind their dorsal fin. Like Atlantic spotted dolphins, they accumulate their spots with age, which allows researchers to readily document age-classes within groups. This species is strictly oceanic in its distribution. Pantropical spotted dolphins are not as frequently sighted as Atlantic spotted dolphins in The Bahamas. They occur in groups of 50-100 dolphins and are often seen engaging in acrobatics, such as making high leaps out of the water, and bow-riding.

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ROUGH-TOOTHED DOLPHINS Steno bredanensis

These dolphins are dark grey in colour with a long beak and prominent white lips. Their lower jaw and belly can sometimes be a pinkish colour. They reach just over 8 feet in length. They are an oceanic species and although appear to be rare in some parts of The Bahamas, can be regularly seen in the Tongue of the Ocean where they occur year round. Some individuals have been re-sighted in this area over the past ten years. They are typically found in groups of about 20 animals, but are sometimes in larger mixed-species aggregations of several hundred dolphins.

Risso's Dolphin - BMMRONot on a stamp but shown on the First Day Cover

RISSO’S DOLPHIN Grampus griseus

These are large light grey dolphins that can reach over 13 feet in length, and have a relatively tall, dark dorsal fin. Adults are typically covered with overlapping white scars caused by the teeth of their con-specifics making them look quite battered. They have a rounded head, lacking a beak, but have a deep vertical crease down the center of the forehead. As they mature, their forehead becomes prominently white, and as such they are one of the easiest species to recognize at sea. Risso’s dolphins are commonly seen in oceanic waters in the northern Bahamas each winter and spring, primarily on the Atlantic side of the islands. It is unknown where these groups range the rest of the year, but some individuals have been seen off Abaco repeatedly over the years.

RELATED POSTS

BAHAMAS WILDLIFE STAMPS PAGE

PHILATELY WILL GET YOU…

ABACO BIRD STAMPS

Bottlenose Dolphins, Rocky Point, Abaco (Keith Salvesen : BMMRO) 7

Credits: BMMRO for relevant text & images except last (RH), Pobjoy Mint, Bahamas Philatelic Bureau

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

CONCH QUEST: ABACO’S MOST VERSATILE GASTROPOD


Conch Shells, Sandy Point, Abaco

CONCH QUEST: ABACO’S MOST VERSATILE GASTROPOD

The conch. Such a fascinating gastropod, and with so many uses both culinary and decorative. In certain cultures, religiously significant. A rudimentary musical instrument for a shell.  And did I mention delicious? 

Live conchs enjoy motoring around uninhibitedly on the sea floor, keeping an eye out…Conch on the move ©Melinda Riger @ G B Scuba copy Conch Man-o-War Cay, Abaco (Charmaine Albury) copy Conch in shell ©Melinda Riger @ G B Scuba copy

Conchs also enjoy racing each other…Conch race ©Melinda Riger @ G B Scuba copy

“Eat my dust…”Conch Trail ©Melinda Riger @ G B Scuba copy

Conch Pearl – one of the rarest natural pearls in the worldConch Pearl (Ambergris Caye Beize)

A conch spiral close-up

Conch close-up, Abaco (Rhonda Pearce)

Conch shells just lie around the place at Sandy PointConch Shells, Sandy Point, Abaco (Keith Salvesen) 2Conch Shells, Sandy Point, Abaco (Keith Salvesen) 3

Conchs are widely used for serving cocktails or as ashtrays in the best beach bars*Conch Shells, Abaco (Keith Salvesen) 1

*This is a lie. Sorry about that. I meant to say “make prefect table decorations”

Image credits: Keith Salvesen / RH (1, 9, 10 ,11); Melinda Riger / GB Scuba (2, 4, 5, 6); Charmaine Albury (3); AmbergrisCaye.com (7); Rhonda Pearce (8) 

WHALE-WATCHING: THE APPLIANCE OF SCIENCE


Blainville's Beaked Whale, Sandy Point, Abaco 14 (Keith Salvesen

WHALE-WATCHING: THE APPLIANCE OF SCIENCE

The Bahamas Marine Mammal Research Organisation has just celebrated its 25th year of existence. It was formed in 1991. The omnivorous leviathan Amazonus giganticus emerged in 1994 and the invasive species Megacorpus googleii not until 1998. A full 10 years later the first garbled recordings of Sarahpalinus illogicus were made. And all the while, a watchful eye was being kept on the cetaceans of the Bahamas – researching, counting, measuring, identifying, recording, poop-scooping, analysing samples, tagging, comparing, protecting and conserving. 

Blainville's Beaked Whale, Sandy Point, Abaco 20 (Keith Salvesen

As the years passed, so the science and technology evolved and became more sophisticated. Researching became at the same time easier, yet more complex as the organisation’s remit expanded to accommodate the vast increase in data collection now made possible by refined techniques. Here are two very recent examples – 25th anniversary projects, in fact – with thanks to Charlotte, Diane, their team and their colleagues in linked organisations.

TAGGING BLAINVILLE’S BEAKED WHALES

Last month, a tagging project started, involving suction cups being attached to the backs of BLAINVILLE’S BEAKED WHALES. The purpose of the research is to compare the foraging efficiency of the whales in Abaco waters with those of Andros, the second part of the project. I imagine this will provide valuable insights into the whale movements and behaviours in each location as well as such issues as the comparative availability of the food supply, and other factors that may affect expected foraging patterns. 

The tag is moved towards an adult male. Note the aerial (antenna?) at the back of itTagging a Blainville's beaked whale with a suction cup 1

Planting the tag on the whale’s backTagging a Blainville's beaked whale with a suction cup 2

Successful suction!Tagging a Blainville's beaked whale with a suction cup 3

The tag in placeTagging a Blainville's beaked whale with a suction cup 4

The tag is tracked for 18 hours, after which it is retrieved and the recordings can then be analysed back at BMMRO HQ in Sandy Point. So far, an adult male, a young male and two adult females have been tagged. Each female had a calf, but these were not tagged.

Female beaked whale with her calfBlainville's beaked whale female and calf

AERIAL PHOTOGRAMMETRY USING A HEXACOPTER

Drone technology is rapidly expanding as new uses for them are devised. BMMRO in conjunction with NOAA have used a sophisticated HEXACOPTER to take the first  PHOTOGRAMMETRY images of Blainville’s beaked whales. These aerial photographs were taken from approximately 100ft altitude. But note: not just anyone with a $50 drone can do this: the project required flight clearance from the Bahamas Department of Civil Aviation and a permit for research on marine mammals granted by the Bahamas Department of Marine Resources.

 Blainville’s beaked whale photogrammetry image – adult male (note ‘erupted’ teeth) Blainville's beaked whale photogrammetry image - adult male (note 'erupted' teeth) BMMRO

 Blainville’s beaked whale photogrammetry image – female and calf Blainville's beaked whale photogrammetry image - female and calf BMMRO

STOP PRESS Two additional images from the latest batch Blainville's beaked whales photogrammetry image - BMMRO  Blainville's beaked whales photogrammetry image - BMMRO

Photogrammetry: the science of making measurements from photographs. Applications include satellite tracking of the relative positioning and alterations in all Earth environments (e.g. tectonic motions etc), research on the swimming of fish, of bird or insect flight, and other relative motion processes. The results are used to guide and match the results of computational models of the natural systems. They help to invalidate or confirm new theories, to design novel vehicles or new methods for predicting or/and controlling the consequences of earthquakes, tsunamis etc, or to understand the flow of fluids next to solid structures, and many other processes. (Wiki-précis)

Hexacopter (6 rotors)Hexacopter_Multicopter_DJI-S800_on-air_credit_Alexander_Glinz

Tag Team: BMMRO, University of St Andrews (Scotland), Woods Hole Oceanographic Institution

Hexacopter: BMMRO, NOAA

Photo Credits: top two, moi (from BMMRO research vessel); remainder except for last, BMMRO; last, Wiki

WORLD OCEANS DAY 2016: “STASH THE TRASH”


View from a Skiff, the Marls, Abaco, Bahamas

WORLD OCEANS DAY 2016: “STASH THE TRASH”

Today the NOAA and other worldwide ocean guardian organisations are celebrating World Oceans Day. Looking at the websites and FB pages, one message is clear: People Are Rubbish. To put it another way, the global pollution of the oceans is caused solely by humans. The pristine seas and beaches of the world were unsullied until, say, the last 200 years. In 4 or 5 generations, all that has changed irreversibly.

Leave only Footprints - Delphi Beach, Abaco

My rather (= very) negative intro is counterbalanced by some more positive news: there are plenty of good guys out there working hard to make a difference to the rising tide of filth polluting the oceans. Clearing seas and beaches of plastic and other debris. Collecting tons and tons of abandoned fishing gear. Rescuing creatures trapped, entangled, injured and engulfed by marine debris and pollutants. Educating adults and – far more importantly – children and young people by actively involving them in their campaigns. Conducting research programmes. Lobbying and protesting. And a lot more besides.

A marine garbage patch: the sea creatures’ view (NOAA)Marine Garbage Patch from below (NOAA)

Abandoned fishing gear: a monk seal that was lucky; and a turtle that wasn’t (NOAA)Monk Seal in discarded fishing nets (NOAA)Sea turtle trapped in abandoned fishing gear (NOAA)

Four shearwaters killed by a cone trap. A fifth was rescued (NOAA)13138799_1188762361142231_1433873125345242619_n

The NOAA and sister organisations carry out massive programmes of clearance of marine debris, with working parties of volunteers who do what they can to deal with an intractable problem.Clearing Beach Debris (NOAA) Clearing Beach Debris (NOAA)

But you don’t need to be on an official working party for a large organisation. In the Bahamas and on Abaco, the BAHAMAS PLASTIC MOVEMENT, FRIENDS OF THE ENVIRONMENT  and BAHAMAS NATIONAL TRUST among others, do wonderful work on a more local level.
Childen collecting beach debris, Abaco (FotE)

HOPE  FOR  THE  FUTUREYoung conservationist on Abaco, Bahamas

Elsewhere, some tackle the problems caused by particular types of trash, balloons being an excellent example. I have posted before about BALLOONS BLOW, the brainchild of two sisters who learnt of the serious consequences to wildlife caused by mass balloon releases. Their work has been so effective that increasing numbers of mass releases are being cancelled in favour of other forms of celebration. A minus for balloon-makers of course, but a big plus for wildlife. The BB sisters also keep their own beach clear of the junk brought in on every tide.

Balloons Blow - Beach Debris (http://balloonsblow.org) Balloons Blow - Beach Debris (http://balloonsblow.org)

And on an individual basis, any old fool can make a tiny difference to a local beach. Here is one such doing just that…

A tangle of balloon strings on Delphi beachBalloon Strings, Delphi Beach (RH)

Guinea Schooner Bay: little visited, rarely cleaned. Plastic crap from a 10 foot radiusRH & trash, Guinea Schooner Bay

Credits: NOAA, FOTE Abaco, BPM, Balloons Blow, RH, Mrs RH

MAKE FRIENDS WITH ANEMONE (2): SPECTACULAR REEF PLANTS


Corkscrew Anenome = Peterson Cleaner Shrimps ©Melinda Riger @G B Scuba copy

Corkscrew Anemone with Peterson Cleaner Shrimps

MAKE FRIENDS WITH ANEMONE (2):  SPECTACULAR REEF PLANTS

Going snorkelling? Planning a scuba day on the reef? You’ll see wonderful fish and amazing coral for sure. But sometimes the beauty of the plant-life on the reef can be overlooked. Check out the anemone in the header image, with the camouflaged cleaner shrimps playing around it. You wouldn’t want to miss a sight like that. The many and varied forms and colours of anemone on the reefs of the Bahamas make up a vital component of a spectacular underwater world.

Giant Anenome ©Melinda Riger @ G B Scuba copyGiant Anemone ©Melinda Riger @ G B Scuba copy 4Anemone Melinda Riger @ G B ScubaAnemone on Rope ©Melinda Riger @ G B ScubaAnemone ©Melinda Riger @ Grand Bahama ScubaAnemone (Giant) ©Melinda Riger @GBS copyAnemone ©Melinda Riger @ GB Scuba

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

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