Interested In Aquaculture? Here’s A Great Book

Aquarists are becoming more and more interested in aquaculture. This is evidenced by the large numbers of corals being cultured by hobbyists which are then swopped with other hobbyists or taken to the local retailer to exchange or get a credit. Then there are the increasing numbers of fish that are being home bred, though fish breeding is more difficult and requires more dedication.

All of this activity just goes to show how the marine hobby has advanced and is advancing. It really is good for both the hobby and the wild reefs. Even conservationists could find the good in it!

Whether the aquaculture effort involves ‘fragging’ one coral, or the hobbyist is more ambitious and has a dedicated aquarium for the purpose doesn’t matter - it is a very interesting and worthwhile pursuit. If just one or two corals are ‘fragged’ and brought on in the existing display aquarium it doesn’t cost a thing either.

I have to state that the book I have in mind here is not really for those who are not ‘into’ aquaculture. Indeed, it goes beyond this and looks at the much wider marine world, considering such things as international trade in reef life, the aquarium industry etc. It also includes such subjects as live rock cultivation, corals, ornamental shrimp, hatchery routines, feeding, seahorses etc. It should be interesting for just about any keen hobbyist, but is involved with future trends and methods in a serious way so a wider interest in the marine world is really required.

It is a hardback authored by James Cato and has contributions by many other authors. The book contains 444 pages and has 169 illustrations. It should be a good addition to any suitably keen aquarist’s library.

http://www.blackwellpublishing.com/contents.asp?ref=9780813829876

(Aquarists Online and other associated websites have no interests, commercial or personal, with the above link)

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Tags: aquaculture, aquarium, coral conservation, Coral Propagation, Coral Reef, home-aquarium, reef-fish

Is It All Doom And Gloom? Total Impending Disaster?

Whatever we read in newspapers or watch on TV there seems to be an element of impending disaster somewhere in the natural world. Is it that bad?

First of all it should be remembered that newspapers and elements of TV thrive on ‘doomsday.’ Without bad news there will be a struggle to find a good enough headline. The media, in my opinion anyway, often makes mountains out of not always molehills but hills. It sells, which probably says a lot for all of us!

The major concern with the natural world used to be the cutting down of the world’s rain forests and this remains a high priority. These rain forests have been called the ‘lungs of the earth.’ The issue is even more important now that science has accepted that global warming actually exists. The majority of the public also accept the situation, though there are still those who remain in denial and state it is just a massive scam. The rain forests are capable as I understand it of absorbing very large amounts of greenhouse gas (carbon dioxide) - provided the trees remain standing of course.

But this is a marine hobby website not a discussion forum on rain forests. So fair enough, what about the rain forests of the seas and oceans, the coral reefs. There’s plenty of doom and gloom in this area also. The oceans are acidifying because of absorption of carbon dioxide and also warming up. So if the corals don’t melt because of reducing pH they’ll die because they cannot tolerate the rapid increase in seawater temperature (rapid when compared to the length of time reefs have existed). Also seawater levels are rising and that causes additional problems for the corals. Now all of that’s nirvana for the gloom merchants!

There is a serious problem. There isn’t any denying it, the evidence is available for anyone to see, scientist or not. In some quarters it is said that the reefs are in terminal decline. It has been reported that the rate of decline is 2% each year. Doesn’t seem much but in fact it’s a lot. It has also been reported that around 1/5th of reef life has already disappeared overall, though of course some reefs are in better condition than others.

Reefs in general, though not all of them it depends a lot on location, have been getting into trouble because of us, mankind, for a while quite apart from global warming. This trouble has been due to overfishing, incorrect fishing methods (cyanide for example, which kills lots of creatures besides those targeted - those targeted often die later as well), using dynamite on the reefs to obtain building materials, run-off of silt from the land caused by de-forestation, and run-off of agricultural and industrial pollutants. There’s probably more.

These problems have been bad enough and the reefs now have to also deal with global warming, and they’re not doing well. What a sad and dismal sight it is to see pictures of dead reef areas - just rocks with a few forlorn looking fish around. I, like so many others, have been fascinated when snorkeling over reefs, with all the rainbow colours of the fish, swaying soft corals and the reef builders, the hard corals. How could it have come to such a situation! Sadly, it has.

However, I am neither a pessimist nor an optimist, but a realist. I see these as: optimist, ‘Oh, it’ll be all right, you’ll see,’ pessimist ‘It’s all a disaster, it’s too late, it’s all doomed,’ and a realist ‘Strewth, what a mess, hopefully the scientists might be mistaken though that’s unlikely. What can be done about it?’

There are some hopeful signs.

It appears that the politicians, usually never the ones to move at more than a snail’s pace, have accepted the overall problem (overall = global warming in general) and are looking to do something about it. They need by all accounts to move more quickly, but it has to be accepted that there’s a great deal to consider. The political area is of the utmost importance above anything else. If reasonable agreement can be achieved then the problem can be tackled.

In some of the natural reef areas corals are being grown from ‘frags’ (a frag is a cutting taken from a soft or hard coral). They are grown on extensive trestles beneath the sea. When they are large enough they are transferred to the reef and hopefully in time more corals can be grown from them. If the reef is in danger because of man-made problems, unless those problems are tackled, this action can only be at best a holding operation.

The marine hobby aquarium trade, which to my knowledge has not been accused of causing problems (unlike for example those who collect seahorses for alleged medical purposes or dry them for souvenirs), has tackled some recognized bad practices. Local collectors have been trained to collect in an ethical way and not use cyanide, thus protecting reef life in general and giving caught fish a better chance of continuing to live. Many retailers have voluntarily joined organisations that promote good retail practices, such as importing livestock from recognized sources only and keeping them in appropriate conditions until sold. Imports of livestock for the marine hobby overall are huge and it is obvious that the more sea life is protected the more the reefs will benefit.

What about us marine aquarists? Oh great, here it comes, we must try harder and ‘be good.’ Not at all! There are poor and ineffective aquarists who would be better off giving up the hobby, but they are a small minority.

The marine aquarium hobby has advanced unbelievably over the last decade. Aquariums of all sizes, reef or fish only, are being kept successfully, supported by advanced and reliable equipment. Aquarists have access to huge amounts of information, not only books but through that electronic wonder of the age, the internet. The results of all this can be seen by looking at pictures, a great number of these marine aquariums are truly beautiful.

Keeping a successful aquarium (that is, keeping it healthy for a long period measured in years) is not the major concern. Of course it is very important; a failed aquarium is a mini disaster in itself particularly for the unfortunate livestock. The major concern with the hobby now is production of livestock. It really heartens me when I see how many aquarists are producing home grown corals from ‘frags’ - corals that have not come from the wild but from an aquarium. These are appearing in such numbers now that, if it is not happening already, it will soon have a measurable impact on imports from the wild reefs. There is a further credit to this, and that is that the home grown corals are reputedly less sensitive in an aquarium than those from the wild, which makes sense.

On the same basis, but more difficult to achieve are the fish that are being home bred. These are not appearing in such numbers because of the inherent breeding difficulties. It was a great achievement when clownfish first appeared in dealer’s aquariums having been supplied from home sources. Now many more fish species are appearing as time goes by and one can only salute the patience and knowledge of those aquarists who are involved. How must those aquarists feel as they look upon a tank full of successfully grown saleable fish!

There’s another point about the marine aquarium hobby too. I’ve mused in the past about how big the hobby really is - could it possibly be the biggest hobby in the world? I don’t actually know, but I wouldn’t be surprised if it was. With obvious exceptions, over the globe there are many, many marine aquarists. They keep fish or fish and corals. No matter which, what they have in total is a massive reserve of livestock, both fish and corals.

Already large numbers of corals can be home propagated. As said, the number of fish species that are being home bred is increasing. Perhaps in the future, when the politicians have reached some agreement and global warming and pollution problems have been tackled, marine hobbyists will be able to supply stock for the wild reefs.

How great would that be? Traffic in reverse. Beautiful reefs partially re-built from our aquariums.

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Tags: aquarium, Coral Reef, marine-aquarium, reef conservation, reef-tank, saltwater-aquarium

Demand For Clownfish May Be Putting Them In Peril

I read an article today which is basically saying that the numbers of clownfish have fallen by the region of 75% in some areas of the world.

The marine biologist who performed this study is putting this down to the Finding Nemo film.

I am not sure how true this is as it was just an article I was reading and was not the actual report from the marine biologist in question.

What they have said is that even though the Finding Nemo film is now around five years old children and adults alike are so taken with ‘Nemo’ that they want their very own Nemo lookalike.

I remember thinking at the time of the film that this could be good for the hobby but also thinking that it could be quite bad for the hobby. I was very dissapointed to see a lot of Finding Nemo aquariums coming up for sale with clownfish, regal tangs etc all being made available for sale in aquariums which were just too small for them. A lot of shops I admit refused to sell these items but there was a lot that did.

Don’t get me wrong I do think that the film did a lot of good for the marine hobby as it raised awareness of it but people started purchasing fish just because of the film without doing any research first as to what their requirements were. As we all know and John and I go on about it all the time research is imperative in this hobby - there is life at stake and we as responsible aquarists need to ensure that we do everything in our power to ensure that they are well cared for.

Anyway the study was apparently a five study of clownfish in Australia and on one coral reef his research found numbers had fallen from 25 to just 6.

If true it is quite worrying. I admit that you are able to purchase captive raised clownfish and I urge anyone who is interested in purchasing a fish to consider captive raised. not just for clownfish but for any fish.

It is the belief of the marine aquarists that clownfish should now be put on the endangered list.

One statement the marine biologist made was one I actually quite liked :

‘My message to kids who love the film is simple - tell your parents to leave Nemo in the sea where he belongs’

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Tags: Care, clownfish, Coral Reef, finding nemo, marine-aquarium, saltwater-aquarium

Flying Will Cost More

‘What on earth is he bleating on about now?’ I can hear it said. ‘I thought this was a marine aquarist’s site.’

Well, it is a marine aquarist’s site. Also flying will cost more, and it will have an impact on marine aquarists.

Everything seems to be creeping upwards in price, all apparently because of the huge demand for oil worldwide, particularly now that China and India have developed. The demand is currently outstripping supply according to the experts.

So it is with air travel. Passengers are facing ticket price increases and fuel surcharges. The same increases apply to air freight.

For the most part, the livestock we keep in our aquariums comes from the wild reefs and the journey has to be paid for. Air flight is brilliant because time between start and finish is minimised. Livestock is suitably boxed so that transport is as efficient as possible, but it still costs a lot, and the cost as said is increasing.

The increased cost will no doubt feed through the system to the consumer, so the aquarist will have to pay more for fish and corals. The cost of corals may increase the most, at least those that are attached to and travel with a piece of rock, which will be because of the weight. Live rock will likewise probably increase in cost.

This will just be a fact of life that the aquarist has to contend with. There’s not much that could be done about it - there might be some assistance if it was an essential but it isn’t, it is an inessential luxury. I’m sure that the marine hobby isn’t going to reduce overnight, in fact I feel reasonably sure the hobby isn’t going to reduce.

There is an aspect that brings relief to the ’what if’ question. This is that, more and more, aquarists are propagating (”fragging”) corals in their aquariums, or in aquariums that have been designed specifically for the task. This applies to both soft and hard types. Even if the aquarist isn’t too bothered about propagation, corals grow, and to keep the captive reef in good shape some pruning is necessary. The removed parts of the coral can simply be taken to the local marine store for onward growth, or passed to another aquarist who is more keen on propagation and has the facilities. Coral propagation is generally very straightforward.

Breeding fish is also being done by hobbyists. Probably the best example are clownfish. There are several others. Breeding marine fish is more complicated and requires considerably more dedication, but the practice is increasing, both with the currently relatively few advanced hobbyists and also commercial organisations.

As cost pressures mount on wild imports, so commercial organisations should hopefully increase their efforts in producing livestock for the hobby. As wild caught livestock begins to cost more, commercially produced livestock should be able to compete more effectively as, generally speaking, there does not need to be any air travel involved, or if it is necessary at least it will not have to cover the same distances. Commercial organisations that operate in warmer zones will also minimise the cost of the energy they require.

There are two advantages and one disadvantage in being able to obtain home produced or commercial livestock. First, it seems to have been generally shown that livestock produced in aquariums are more hardy. This seems reasonable - they are to be kept in aquariums. The second advantage is that the pressure on the wild reefs will be eased, which will no doubt please environmentalists/conservationists. So what might be the disadvantage? A considerable number of local people in the reef areas have employment because of the aquarium trade, and no-one would want them to suffer.

The future cannot be seen, but I reckon the marine aquarium hobby is well placed to continue to bloom, perhaps with a few adjustments along the way.

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Tags: aquarium, Aquarium Maintenance, Care, Coral Propagation, Coral Reef, Equipment

Shaping To Circumstance?

The beauty and diversity of a wild reef is well known. Fish and corals have adjusted to their niche.

What about the captive reef? The aquarist does his/her best to meet the needs of the corals (and fish) to try and ensure their health and longevity. The fish and corals have preferences. For a fish example, many wrasse like to bury themselves in sand and so the aquarist provides it in sufficient depth. Corals have a spot on the reef too, where they are subject to varying seawater currents, light intensity and spectrum. The aquarist tries to meet these differing needs as well.

What if the coral receives continuous directional seawater flow, not strong enough to cause damage, will the coral react? Well, yes, it usually will over time. A land based tree subject to nearly continuous directional wind will lean away from the wind, thus reducing the trees resistance to it. So it is with corals - a coral with directional water flow will tend to grow heavily influenced by that flow. If it is a branching coral, probably particularly a ‘hard’ type, it will reduce the resistance to the flow by growing ‘with’ the flow - in other words it will lean away from the flow.

On the wild reef a hard coral near the crest where it is subject to great turbulence and wave power will have short stubby branches to present less resistance to the water. In areas of less flow, the branches will be longer and possibly more slender.

In a similar way some corals react and grow according to light availability. The shapes are natural, and these are the normal shapes the coral is expected to be. The coral in the wave area with short branches receives considerable light as it is near the surface, so the short branches are not a problem. The coral lower down with less seawater turbulence has longer branches and thus more is exposed to the lowered light level. Some corals form horizontal plates which often overlap one another, and these present a large area for light to strike.

I keep a soft coral reef and wonder if the same thing applies to these. I know the shape and the lean of the coral can be influenced by water flow, but wonder if these corals can alter their growth to gather the light they need? What if they need more light and are in a position too low down to get it?

I have been watching the growth of a soft coral for quite a time. It appeared very close to the bottom of the reef, and the growth is slow. The water flow is quite gentle in the coral’s area but is sufficient and multi-directional, and I don’t believe this influences it particularly.

The coral is a normal branching type, that is, it would normally grow vertically with several more or less vertical branches, with a few side growths as well. It started very small, and I assume it is a ‘dropped’ branch or similar as I didn’t place it there.

The aquarium is 24″ in depth and lit by an array of fluorescent tubes (marine white and actinic blue). I assume the coral’s growth is slow as it receives low light.

The interesting thing is, the coral spent a long period not growing toward the light as might have been expected, but growing horizontally. I wonder if this was to gather as much light as possible by presenting the largest surface to the available light as possible? The coral is now showing vertical growth in several places, so maybe it has enough energy now to be able to do so?

I don’t know what the answer really is, but the above seems feasible as fluorescents are not able to punch much light into nearly 24″ of seawater.

There’s a photo to show the coral (it is now about 5″ across) - I’m not a photographer so I apologise for any shortfall.

Aren’t marine aquariums interesting! There’s always something to watch, just for pleasure or to ponder over.

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Tags: Aquarium Lighting, aquarium-coral, Coral Reef, hard coral, reef-tank, soft coral

Are You A Scuba Diver?

Scuba divers are those strangely garbed people who flip-flop in an ungainly manner down the beach toward the sea, or roll into the sea from the side of a boat.

Once in the sea it is a different matter. Within safety parameters the diver is free to explore, to cruise along weightless. Nowadays scuba diving has a large following and many head for the reefs. It isn’t surprising really, what better place to explore than a wild coral reef. Down in the domain of the fish, seeing more or less what they see.

I’ve had the good fortune to have had a look at reefs in the Pacific Ocean, Indian Ocean, Red Sea etc and they truly are wonderful. But not as a scuba diver.

When in the Maldive Islands, Indian Ocean, for a holiday, I intended to take a training course to become a qualified scuba diver. Diving goes in stages, and the initial qualification is to dive to a maximum 60 feet. Then, if desired, further courses can be undertaken for wreck diving etc. Anyway, I wanted the initial course.

It didn’t happen though. I haven’t a problem with my ears until I get into the sea. I should say get under it to any depth. As the depth increases, say beyond 10 feet, the pressure causes considerable ear pain. I tried ear plugs to no avail. The instructors didn’t understand the problem, but of course - no diving course.

An acquaintance on the same course also had trouble, not with his ears but his face. No, he didn’t come out in spots - he had a ‘craggy’ face, deeply lined. When under the sea his face mask flooded and this happened every time no matter what was tried. So no diving course for him either.

I spent my time on the reefs with snorkelling gear. This gives a great ‘overview’ of the reef and everything is still wonderful to behold. I will always remember putting my head down for the first time and seeing powder blue surgeons, what a sight! An Emperor Angel majestically cruising along the reef face. Lots of memories.

I don’t feel as though I’ve missed out at all, I’ve seen some amazing things and got close up to a lot of them. A bit too close sometimes - waves pushing me onto sharp coral was a bit too close, or a large eel appearing in front of my face made me back off. I managed to dive down to perhaps 6 to 8 feet if something caught my eye.

So if you are a scuba diver, I’d have liked to have been in the club. If not or you don’t fancy it, if you’re going anywhere near a reef have a go with snorkelling gear.

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Tags: Coral Reef, natural reef, scuba diver, scuba diving

Do Fish Drink?

As far as I know all life needs water to survive. Doesn’t matter if it is a cactus in a desert or a tree in a rain forest, it needs H2O.

What about fish though? They’re surrounded by the stuff, absolutely gallons of it.

Fish are life forms of course and so they too need water.

The type of water that surrounds them plays an important role in how the fish obtain the stuff. The water can be fresh or salt.

Fresh water fish absorb water through their skin. They also have methods of ridding themselves of excess water without losing the important salt within their bodies.

Marine fish are the same in that they need to keep a certain concentration of salt in their bodies. Of course, marine fish are surrounded by salt and water. What they do is drink the seawater and the gills process the water removing the salt. In marine fish it is the retention of water that is the problem, and to combat this some of them have inefficient kidneys or do not have kidneys at all.

Anyone wants to read a bit more here’s a link:

http://www.madsci.org/posts/archives/1996-12/847855291.Zo.r.html

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Tags: Coral Reef, coral-fish, marine reef, marine-fish, reef-fish, saltwater-aquarium

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