‘Technical books take many forms, but those that are truly original
radiate both a purpose and a point of view. The ideas presented are alive
and vibrant, suspended in a force field between the poles of imagination
and scholarship. The writing is clear and bold without fear of solecisms.’
Not my words, but those of Stephen Spotte in the preface to his book. I
admit to blinking at these and other florid preliminary comments made on
what, from the title, one might assume is a conventional textbook on the
culture of marine fishes. Not so, says Spotte: ‘Anyone expecting a handy
reference volume faces disappointment; this book is organised to be read,
not consulted. Captive fishes demand an intellectual tithe from those who
curate them.’

I read this exhortation, gazed at the formidable 5-centimetre thick
volume and gulped. I well remember years ago wading through two similarly
intense but slimmer publications by the same author: Fish and Invertebrate
Culture: Water Management in Closed Systems (Wiley, 1970) and Seawater Aquariums
(Wiley, 1979). Much that is contained within these earlier useful and well-produced
works is elaborated upon in this new offering, which is designed mainly
for managers of public aquaria and, to a lesser extent, general aquaculturists.

Spotte has flouted the convention of directly citing other scientists
or technologists to keep the core work unencumbered. Instead, there is
a comprehensive list of literature for each chapter, and 208 pages of detailed
technical discussion martialled in a notes and references section. He indicates
these in the main text by numerical superscripts. The effect of this can
be confusing, and it is not always possible to determine the particular
contributions of the various authors. Spotte correctly anticipates the reader’s
irritation in having to flick back and forth from text to notes, and grandly
relates it to a similar problem with Vladimir Nabokov’s Pale Fire, where
the recommended solution is to buy an extra copy of the book and cut it
apart.

From the introductory hype promising an exhilarating experience, I
expected to be assailed on each page by advanced and controversial ideas
in science and technology. With this in mind, the first part of chapter
one proved a disappointment: ‘Everything in the universe is made of matter.
In its simplest form matter is composed of elements. Atoms are the smallest
particles of elements that combine to form molecules.’ Moving on to technology,
I felt my eyelids droop when it came to instructions on how to calibrate
a thermometer at sea level. While Spotte clearly wishes to start from scratch
with each topic in order to foster understanding, it would have been better
to leave out rudimentary aspects of chemistry, physics and biology.

Despite the all-embracing title, tropical coral reef rather than cold
water marine fishes are the main subject. Paradoxically, parts of the discussion
depend on studies of freshwater fishes as models for aspects of physiology,
behaviour, ecology, nutrition and clinical health. The detailed and extensive
treatment of ecology and behaviour in nature is fascinating but the lessons
to be learned in terms of captive management are not always clear. Indeed,
this is a central problem with the whole book. The author disarmingly admits
that: ‘The urge to drift away into this labrynth of endless corridors was
difficult to resist.’

Forgetting all the digressions, the book contains much of practical
interest including, for example, doubts cast on the efficacy of numerous
compounds used in the treatment of fish diseases; and the view that, given
a preferential metabolic utilisation of lipid, the addition of both carbohydrate
and lipid to the diet of carnivorous sea fishes in captivity is not beneficial.
There is also a valuable chapter on exhibition techniques, although this
is surprisingly brief in relation to the size of the entire volume and its
intended readership.

Eight years in the writing, the book is clearly a labour of love, and
one must admire the author’s boundless enthusiasm and breadth of scholarship.

In conclusion, I cannot do better than quote from Spotte’s introductory
defence of his magnum opus: ‘Authors who opt for originality risk criticism
from conservative peers, but such risks are worthwhile when the alternative
is a featureless landscape unmarred by curiosity.

Gordon McGregor Reid is Curator-in-Chief of the North of England Zoological
Society, Chester. He has a special interest in fish and underwater conservation.

Recently, in a Sunday colour supplement, I was entranced by a ‘reef
encounter’ – a dazzling photo-documentary by Jeffrey Rotman. Celebrated
as one of the leading marine photographers in the world, Rotman has spent
20 years of his life capturing on camera the immense beauty and diversity
of living coral. Having now seen the published tropical marine photography
of relative newcomer Jeremy Stafford-Deitsch, I must warn Rotman that he
has serious competition.

In fact, comparisons are unfair. Rotman, using a hand-held flash and
reflectors for light, excels in close-up or macrophotography of a few square
centimetres of reef, while Stafford-Deitsch best achieves sweeping panoramas:
brilliantly composed, multihued and of astounding clarity. Huge starbursts
of green, orange, silver, purple and electric blue fish populate elaborately
branched and impossibly gaudy waterscapes of coral, sponge, and coralline
algae.

This is, however, no mere polychrome coffee-table extrava-ganza. Stafford-Deitsch
studied zoology and philosophy at the University of London, and each of
his photographs is accompanied by well-written, thoughtful observations
on the natural history of coral reefs from the Red Sea, Caribbean and western
Atlantic through to the Indo-Pacific of Papua New Guinea. It is strange
to contemplate that dramatic scenes, briefly illuminated by a strobe light
at 50 metres in breathtaking colour, instantly return to a sombre blue grey.
While pattern, brightness and contrast may (depending on particular visual
systems) be of importance in camouflage or reef species interactions, the
biological function of colours normally masked at depth is not well understood.
For example, some vivid red and yellow pigments widespread in marine vertebrates
and invertebrates are perhaps dietary in origin or stored metabolic by-products
without any set ecological or ethological significance. On this interpretation,
the aesthetic feast that so inspires divers photographing reefs at depth
is simply a delightful product of serendipity rather than a scientific mystery.

No less of a problem in scientific evaluation are the myriad examples
of symbiosis to be found on reefs. These are fully discussed and strikingly
illustrated by Stafford-Deitsch. It begins with the reef-building corals
of the tidal zone. A curious amalgam of animal, vegetable and mineral, these
fleshy colonial coelenterates spring forth from a secreted limestone base.
Each interconnected, flower-like madreporian polyp is impregnated with zooanthellae.
These are algal cells that under optimum conditions of water clarity and
sunlight supply, via photosynthesis, much of the nutritional needs of the
coral animal. This contribution by the plant evidently allows the coral
to mineralise and grow at a rate faster than sea currents can erode it.
The reef-building process often proceeds best at about 26 or 27 °C.
At higher or lower temperatures the coral cannot easily offset wear and
tear from the restless water. Hence reefs subject to prolonged adverse temperature
changes are probably doomed, even if these changes are only a few degrees.

This brings us to the inevitable decline of reefs if a rise in ocean
temperature comes through global warming. Stafford-Deitsch finds that the
balance of evidence is tipping towards the conservationist lobby. He argues
that we desperately need reefs because they have the photosynthetic capacity
to absorb emissions of carbon dioxide as a carbonic acid solution.

Reefs also buffer against marine acidification processes and they may
even regulate biologically crucial oceanic salt concentrations. Certainly,
healthy reefs protect shorelines physically. Disastrous coastal erosion
has resulted where reefs are mined as limestone for building material or
where they have been obliterated through overfishing or agricultural and
urban pollution running off into the sea.

An immediate need for conservation is clearly the central theme of this
book. To bring the point home, it might have been better to juxtapose against
the many pleasing images a few sad pictures of reefs destroyed by the tourist
or souvenir trade (an estimated 1500 tonnes of coral from the Philippines
is exported annually to the US, much of it illegally). Coral reefs are key
habitats that occupy less than one per cent of the oceans and yet they support
at least 4000 different species of fish, perhaps one-fifth of the world
total. Alarmingly, a recent survey by the International Union for the Conservation
of Nature estimates that in the Philippines alone about 80 per cent of coral
reefs are in a poor or only fair state.

Stafford-Deitsch’s photographs offer a rare chance to view in all their
glory those few reefs that are still pristine.

Gordon McGregor Reid has a special interest in fish and underwater conservation.
He will shortly be the Curator-in-Chief, North of England Zoological Society,
Chester.