SCIENCE REPORTER, MAY 201345

ALPANA VOHRA

THE wonderfully glistening and glittering ornamental fish in aquaria are always

a sight to watch. Who would wonder that these beautiful ornamental fish, so aesthetically pleasing to the eyes, could open up avenues for self-employment and entrepreneurship and also play a major role

as economic engines? The global trade of ornamental fish is worth $282 million (Financial Express, 2010). No doubt they are known as ‘Living Jewels’!

Ornamental fish form an important component of aquaculture, providing

for aesthetic requirement and upkeep of the environment. At present the market for ornamental fish in the world public aquaria is less than 1% and over 99% of market is still limited to hobbyists. A relatively less requirement of space or attention

The Aquarium industry comprises not only the culture and trade in ornamental fishes but also their food, related accessories and equipments. This multifaceted industry is experiencing an expansion globally.

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compared to other pets is the reason for the growing interest in keeping aquaria all over the world.

These beautiful creatures not only form a proud possession of an owner but their culture and trade also opens up avenues for self-employment/entrepreneurship.

Role as Economic EnginesThe aquarium fishes have proved to be an important and a fruitful project for entrepreneurship. Over the years, the ornamental fish production for the aquarium industry has become a multimillion-dollar industry in various countries of the world.

Ornamental fishes are a big business and form an important source of income for many rural and coastal communities in developing countries too. These make a global trade of 45 billion US Dollar, which is increasing at an average annual rate of 14% (FAO).

The largest markets of ornamental fishes are USA followed by the European Union and Japan. At present, more than 65% of the global export of ornamental fishes takes place from Asian countries. Singapore dominates by exporting 37% of the total Asian export followed by Malaysia (16%), Indonesia (11%), China (10%), Japan (7%), Philippines (6%), Sri Lanka (5%), Thailand (5%), Taiwan (2%) and India (1%) (Huat, 2005).

Since the demand for good quality tropical ornamental fish far exceeds the supply, ornamental fish culture and breeding holds potential of big earnings not only by selling them in the domestic market but also by exporting. For instance, in local markets, Danio rerio is sold at the rate of Rs. 6 while its value overseas is US $0.16/pair. The cost of D. dangilla in the local market is Rs. 12 while its overseas value is US $1.50/pair (Mahapatra and Vinod, 2009)!

Though there is a vast potential offered by its rich diversity, India has yet to make its mark in the industry. Of the global trade of ornamental fish worth $282 million, India’s share is a mere 0.4% (Financial express, 2010). Though Indian exports rose up to Rs 5.6 crores in 2006-07, yet the growth was insignificant as compared to trade in food fishes which is about Rs 8000 crore per annum.

India has plenty of water bodies rich in fish fauna right from Ladakh to Kanayakumari and from Kucch in Gujarat to the Sunderbans in the east. Yet a capture-based activity is not sustainable in the long run, there is a need to shift the focus from

Aquarium Care• Feed the fi sh twice a day at a fi xed time, remove left over food after feeding• If fi sh are continuously gasping at the surface of water, reduce the number of fi sh or increase aeration and change 30% to 50% water of the aquarium• Aerate intermittently for 6-10 hours in summers and 2-3 hours in winters• Occasionally provide live feed • Avoid:

-overcrowding the aquarium with plants and fi shes-exposure to direct sunlight or artifi cial lights for longer durations-insecticide sprays near aquarium-shifting aquarium when fi lled with water-sudden switching on or off the aquarium lights-overfeeding or underfeeding the fi sh

Xenentodon cancilla Nemachilus botia

Oetoebrama cotio Puntius spp.

Notopterus notopterus

Trichogaster fasciatusAspidoparia morar

Some indigenous ornamental fishes

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capture based to culture based activity with thrust on breeding and restocking of ornamental fishes.

Allured by the fast growth potential of the ornamental fish industry and alarmed by the fact that the boom in the trade is bound to put pressure on natural resources, workers in different parts of the country have initiated work on ornamental fishes and their breeding in captivity using various hormones.

Therapeutic RoleThough the most consequential effect of ornamental fishes is through their role as economic engines their value as stress busters cannot be underscored. It may not be possible to calculate their therapeutic role in monetary terms.

An aquarium is a mini underwater garden that provides a glimpse of the aquatic animal paradise leading to visual and aesthetic satiation. It presents an atmosphere of relaxing serenity along with an opportunity to contemplate the otherworldly grace and beauty of the aquatic realm. An aquarium with an enchanting aquascape brings the beauty of nature to one’s home and offers an access to worlds that we, as terrestrial creatures, must share, yet rarely glimpse!

Patients suffering from heart ailments, nervous disorders, depression and those undergoing post-operative therapies can benefit immensely from indulging in ‘fish watching’. The beautiful aquatic denizens not only provide a serene and tranquil ambience but the graceful movements and playful tactics of these silent companions go a long way in soothing any jittery nerves. No wonder, aquaria are becoming a common occurrence in the waiting rooms of dentists in order to calm nervous patients.

According to researchers from New York State University, ornamental fish pets go a long way in lowering the blood pressure of patients. Studies have further shown that keeping an aquarium not only can keep one relaxed but can also improve one’s health. Alzheimer’s patients react extremely well to an aquarium in the dining area. They ate more, needed fewer supplements and were less aggressive.

Swordtails in their own way have helped in cancer research for human welfare. When a spotted platy was crossed with a related green swordtail, it was found that the resulting offspring invariably developed cancerous outgrowths on the sides of

the body, which resembled some of the human cancerous growths. This lent support to the concept of heritable cancer and also provided the wherewithal to produce cancer at will and to make possible a very quick way of studying the genetics of cancer as these fish breed rapidly.

Research has shown that a well-designed hospital environment can have a substantial impact on patient recovery and welfare. There is ample evidence that shows that exposure to nature has a positive healing effect. Studies have shown that surgical patients with a nature-view showed a shorter length of recovery and fewer complaints. Fish tanks harbouring these undulating beauties have been used effectively for the purpose (Kant and Gupta, 2005).

Tools in Medical Research Scientists are also breeding zebrafish, which have transparent bodies, in order to make studying disease processes easier, including the spread of cancer. The transparent fish allow the researchers to directly view its internal organs and observe processes such as tumor growth in real-time living organisms.

Stem cells from the eyes of zebra fish might be able to restore vision in humans with damaged retinas. The ability of the zebra fish to regenerate damaged retinas has given scientists a clue about restoring human vision that could lead to an experimental treatment for blindness (The China Post, 2007).

EntertainersNot only the wide array of colours and shapes of ornamental fish are enjoyable, their playful antics are noteworthy as well. Ever since the first public aquarium was set up in 1852 at the Zoological Gardens in Reagent’s Park of London, fish keeping has gained tremendous popularity and today the aquarium industry has the potential to exert such potent economic forces that ensure not only an economic uplift of a nation but also cater to conservation of the vanishing wild!

Fighter fishes Siamese fighter fish (Betta splendens) and the half beaks (Dermoejenys pusillus) fetch high price as their fights have been and are traditionally enjoyed and heavy bets are placed on such fights.

Betta splendens (Siamese fighter

fish) (Photo: www.spiderpic.com)

Danio rerio (above) and Genetically modified version (below)

It is high time these aquatic beauties are valued for their monetary benefits and healing touches before they vanish.

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In North America alone some 134 million people visit the 200 or so accredited institutions of the American Zoo and Aquarium Association each year. This number is much more than that which attends all major-league sports venues combined (Stiassny, 2005). The above citation is proof enough of the entertainment value of aquaria.

A genetically modified version of zebrafish (Danio rerio), a native of the Indian Ganges, is available in bright red, green and orange fluorescent colours under a patented brand – ‘GloFish’. Originally, the concept was to develop zebra fish as pollution indicators, which would fluoresce in the presence of environmental toxins indicating polluted waterways. The Glo Fish were an instant hit with aquarium lovers as these are brilliantly colored fish that add colour and excitement to an aquarium (McNamara, 2004 and Nash, 2004).

Biological IndicatorsSince time immemorial, humans have tried to predict the forces of nature. Weather fish (Misgurnus fossilis) has been kept in aquaria for centuries to predict weather forecasts. The fish is very sensitive to changes in atmospheric pressure that bring about changes in weather. The fish becomes restless whenever sudden changes in pressure occur and thus serves as a ‘living barometer’!

Likewise, catfishes like Clarias bactrachus and Heteropneustes fossilis are long known to be of use in forecasting earthquakes. The fish have been reported to dash around aimlessly in aquaria prior to such natural disasters.

Research carried out on such unusual animal behaviour in China indicated that recognition of such behavior in a systematic way could be used, along with other methods, to predict large and potentially destructive earthquakes.

The behavior of an animal might be due to changes in the magnetic field preceding a major earthquake. Such changes may be sensed by energy transfer at the electron level, which in turn, may cause changes in the cellular behaviour evoking unusual response in animals. The living cell is essentially an electrical device and a micromolecular structure that may sense and interpret the electromechanic changes occurring prior to a large earthquake. So, animals may have the means and sensitivity to sort out and discriminate the threatening precursory signals of an impending earthquake, activating a behavior pattern for survival.

Strains of transgenic zebra fish (Danio rerio) that would glow in presence of pollutants could be effective pollution indicators (National University of Singapore, 2004).

From Top : Heteropneustes fossilis; Gambusia affinis ; Rasbora danioconius; Danio devario ; Oxygaster bacaila.

Biological ControlFishes also play an important role in biological control of various pests/parasites, thereby, minimizing the use of pesticides, thus reducing pollution. Fishes act as a low cost resource successful in controlling insect-borne diseases.

Various fishes of ornamental value are known to feed on larvae of insect vectors. Oxygaster bacaila, Danio spp., Barilius spp., Rasbora danioconius, Carassius auratus, Glossogobius giuris are some of the larvicidal fishes that help in controlling many diseases.

In relation to public health, WHO emphasized the utility of fishes in the following control measures:

a.For the control of serious diseases of humans like malaria and filaria.

b.Cyclops feeding fishes for the control of guinea worm.

c.Weed destruction.

d.Mollusc-feeding fishes in Africa that control ‘Bilharzia’.

Various fishes of ornamental value have been effectively used for biological control of aquatic weeds that have spread as a side-effect of ornamental fish trade and are proving to be a nuisance in aquatic ecosystems the world over. Puntius spp., Trichogaster pectoralis, Chanos chanos, Tilapia spp. are a few such fishes that have been used for this purpose.

It is high time these aquatic beauties are valued for their monetary benefits and healing touches before they vanish due to over fishing, habitat destruction and pollution. Our water bodies will be turned into aquatic deserts if they are deprived of these vibrant glories that have the ability to heal not only an individual and his environs but also the economy. Their value as a means to generate currency can be calculated in terms of dollars but their contribution towards aesthetic healing is priceless.

Dr. Alpana Vohra, 781, Sector C, Sainik Colony, Jammu (J&K)-180011

Weather fish (Misgurnus fossilis) has been kept in aquaria for centuries to predict weather forecasts. The fish is very sensitive to changes in atmospheric pressure that bring about changes in weather. The fish becomes restless whenever sudden changes in pressure occur and thus serves as a ‘living barometer’!Patients suffering from heart ailments, nervous disorders, depression, post-operative therapies

can benefit immensely from indulging in ‘fish watching’.

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