SILVERSIDES: BAHAMAS REEF FISH (32)


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SILVERSIDES: BAHAMAS REEF FISH (32)

I have no idea if there is a collective noun for a large group of silversides. ‘Frenzy’ would cover it, but that is reminiscent of ‘feeding freezing’ which has a specialist meaning – and anyway, silversides are crazy even when they aren’t feeding. 24/7/12/365 as far as I can make out. I think ‘a panic of silversides’ might be the answer. They are just… all over the place at high speed. Sometimes swirling around pointlessly, other times moving in unison and suddenly all changing direction simultaneously, like a single creature made of tiny shards of silver.

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There are quite a few silverside species around the world. The ones in the Bahamas are Atlantic silversides (Menidia menidia), also known in the north east of the United States as ‘spearing’. They seem to exist for two purposes. The main one is to be breakfast, lunch or dinner for larger fish, sea birds and shore birds. The other is for their usefulness in scientific research because of their sensitivity to environmental changes. 

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In one sense they are easy prey for predators. A determined fish will always manage a snack by swimming into the middle of a panic and (probably) simply by opening its mouth wide. On the other hand, their sheer numbers coupled with the speed and randomness of movement mean that a single may find a degree of safety in numbers. It’s hard for a predator to target any individual fish in the general melee and confusion. Silversides also favour seagrass beds, which give some shelter and protection – and a reasonably safe place to spawn. Or, as some of these photos show, they will hang around wrecks or squeeze into rocky spaces in the reef.

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A panic of silversides apparently pouring like a waterfall down through a gap in the reefsilversides-waterfall-abaco-kay-politano

WHAT DOES A STATIONARY ATLANTIC SILVERSIDE LOOK LIKE?

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Some time ago we used to go to the reef at Fowl Cay Marine Preserve with Kay Politano, and I would snorkel with a small and very basic lo-res underwater camera. I was hampered by being a disgracefully feeble swimmer; by not having snorkelled for a length of time calculable in decades; and by being a complete novice at underwater photography.  Despite these not inconsiderable disadvantages I managed to cobble together a few short movies on my computer (I was new to that too). Here’s one that nearly works, in that it gives an idea of what happens if you ‘swim with silversides’. I know you scuba guys all swim with sharks, but cut me some slack here please…

Photo Credits: Main photos Melinda Riger of Grand Bahama Scuba; Silverside Waterfall by Kay Politano; motionless silversides by FISHBASE.ORGMusic: Goldon Giltrap, ‘Fast Approaching’

THE CORALS OF FOWL CAY MARINE PRESERVE, ABACO [VIDEO]


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THE CORALS OF FOWL CAY MARINE PRESERVE, ABACO

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I usually have 3 or 4 planned posts on the go. Some are quick to compose, some are not. Especially those requiring technical input from the technically unsound – downloading a video, changing the file format, editing and polishing, uploading to a compatible ‘carrier’ etc. I’ve been meaning to get round to making some fish and reef videos from footage of a trip with Kay Politano of Abaco Above & Below. Now I have…coral8

If you are tolerant enough to at least start this one, which focusses on coral, can I restate the excuses? I swim like a panicking cat. I hadn’t snorkelled for a great many decades years until 2011. I was a stranger to underwater scenery, let alone photography. I wave my tiny camera around too excitedly, though not deliberately to inflict seasickness on hapless viewers… It is a bit less bad this time round, however. Luckily I can tell from my stats if anyone has bothered to click on the video below, and you can rely on me to trash the thing if I find a paltry (or non-existent) response. Best just to watch on the small screen, though.coral14

With those dire warnings, here is the video. I would be very interested to ID all the corals that can be seen. There are the easy ones like sea fan, elkhorn, mustard hill, brain… but what’s that one over there? No, behind the waving one…? Comments / suggestions welcome. And if you don’t much care for coral, there are some pretty fish to look at…

Music Credit: Adrian Legg’s ‘Old Friends’, from ‘Guitar Bones’

ADDENDUM JAN 13 I am really grateful to Capt Rick Guest for taking the time to view the video, and the trouble to analyse the contents. He has very helpfully highlighted many points of interest in the film, both as to coral and as to fish, so I’ll post his commentary in full, with my thanks. Of both interest and concern are Rick’s remarks about the Elkhorn Coral. I had wondered about its bleached look. It’s dying…

CORALS ETC

  • At 0:36 a lavender Sea Fan…(Gorgonia ventalina).
  • At 0:52 Yellow “Leaf”,or “Letuce Coral”. Agaricia species growing around a living soft coral called a “Sea Rod”. Soft Corals have living polyps which feed on plankton just like the hard corals.
  • At 1:02 More Agaricia, and a small Brain Coral at bottom. Either a Diploria, or Colpophylia species.
  • At 1:10 A Sergent Major fish, (Abedefduf saxatilus). One of my favorite Taxanomic names! Behind is mostly dead, Elkhorn Coral. The white areas being indicative of “White Plague”. A disease responsible for Coral Whiting…..Death!
  • At 1:37 A Blue Tang swims over some “Mustard Coral”… Porites porites.
  • At 1:55 A chubby “Chub” swims by. Likes caves and caverns and edible, but not palatable.  
  • At 2:33-38  Much coral bleaching damage here on these Elkhorn Corals.  
  • At 2:40-48 A Thalassoma bifaciatum,or “Blue Headed Wrasse” is swimmin’ about. This guy used to be a lady,but he’s a product of Protandric Hermaphrodism! When there’s a paucity of males in the area, a yellow female will step up and become a male for the school.
  • At 3:29 Lower right: a fine example of Millepora complanata,”Fire Coral”. Fire Coral is more related to Man-O-War, and jellyfish than Corals.
  • At 3:50 More Elkhorn Coral with White Plague  
  • At 4:23 Brain Coral, probably Diploria clivosa 

REEF SNORKELLING AT FOWL CAY MARINE PRESERVE, ABACO


  

You will need: swimming kit; sweatshirt (it can be cold on the boat after snorkelling); stuff for Island Hopping later on, inc. camera, money etc; snorkel practice in the pool if you haven’t used one for (say) 20+ years – use the Club gear; Ian Took’s slim ‘Fishes of the Caribbean Reefs’. NB there is limited room on the boat, so you’ll need a bit of a nifty towel work to preserve modesty when changing…

Kay Politano of Abaco Above and Below in Marsh Harbour pencils in an unspecified number of places for a day’s island-hopping and reef-snorkelling while I find out how many non-fishing-that-day Delphi guests might be interested. Seven sign up, and one morning we all set off to Marsh Harbour. In Kay’s shop we try on our flippers, marvel at the scuba possibilities (a completely implausible proposition for most of us…), then we troop off to the marina and Kay’s reassuringly powerful and safe-looking catamaran. It takes 12 passengers; the other 5 are already aboard. We set off towards a threatening-looking weather front; rain later is a certainty…

Kay and rh at the controls

Passing by several Cays, we arrive at Fowl Cay Marine Preserve and drop anchor. We don our flippers, wrestle with our masks and snorkels, and in turn drop off the back of the boat (ok, stern, is it?) into warmish water, under thick grey cloud. My practice in the Delphi pool has paid off, and soon I am wheezing and gurgling my way towards the reef with my head (mostly) under water, a situation I generally avoid.

I am completely unprepared for what I find when I get to the reef. David Attenborough’s favourite production team has kindly arranged for a wide variety of bright fish, some electrically charged, to come up close and inspect me, an intruder in their world. I’ll spare you the colour-supp superlatives and graphic intensifiers – you’re probably blasé and have seen it all before – but I am totally gobsmacked, even with my mouthpiece in place. It’s all real! It’s even better than TV! And don’t get me started on the coral…

Sergeant Major

Parrot Fish

Blue Tang / Ocean Surgeonfish

Blue Chromis

Sting Ray

While I gasp and bubble my way around, I keep a small waterproof video camera running (see GADGETS review). My swimming is feeble at the best of times, but somehow it all seems to be coming together – my flailing limbs, the laboured breathing, the reef, the fish and the footage. We circle round the reef – occasional pale figures appear in my lateral vision – for about 25 minutes, then return to the boat and the struggle to remove our flippers…
 Everyone is excited about what they have seen (some saw barracudas). Who cares that it’s started drizzling… we are wet already and it’s off to Lubbers Cay for lunch; see forthcoming Island-Hopping Post. And see MARINE LIFE page for more reef fish photos taken on this expedition.

ADDITION April 2012 I notice there have been a few specific searches ‘what is the plural of Sergeant Major?’ Good question. The strict grammatically correct answer is, I suspect (as with the military rank), ‘sergeants major’ because it’s the sergeants who are plural and the ‘major’ is a qualifier to distinguish from other degrees of sergeant (were there sergeants minor, for example). It’s the same with courts martial – not ‘court martials’. BUT it sounds all wrong and pernickety. I reckon the whole fish is a sergeant major. If there are 2 or more, you’ve got some sergeant majors to play with.