I never knew fish could be tattooed so a little online research came up with the following http://www.dgukenvis.nic.in/news03-47.htm
QuoteTUTICORIN Sept. 17. For the first time, the Fisheries College and Research Institute (FCRI) here has come across a ray fish with peculiar markings, probably by acquired by tattooing done by researchers or scientists. The tattooed fish was caught in the trawl net of a fisherman 30 km south of the Tuticorin coast at a depth of 160 metres recently...
...The left side of the dorsal region of the fish is marked with number `3', while the right side is marked with a letter `S'. The fish measures 47.7 cm in length and weighs 500 gms. Experts at the FCRI say that the marking by tattooing is usually done by scientists in fisheries research institutes to study the growth, food habits, reproduction, migration pattern and racial studies of the species. Since tattooing technique is widely done by research institutes abroad, the FCRI has written to South African, Sri Lankan, Australian, Singapore and Malaysian High Commissions in New Delhi to find out whether any leading fisheries research institutes in those countries had tattooed the fish for biological or migratory investigations...
...According to V. K. Venkatramani, Professor, Department of Fisheries Biology and Capture Fisheries, FCRI, tattooing is usually done on juvenile fishes and left in big tanks till the tattooed part is healed. After healing, the fish would be left in open seas to study its migration or biological features. Experts say tattooing is done on a large number of specimen of a particular species. Once the tattooing is done, information is passed on to other fisheries research institutes. Tattooing is considered to be the best technique since it is harmless and the dye mark would be retained permanently on the external body of the fish.
On another more bizarre note http://www.zootoo.com/petnews/lawbanningfishtattooingenenfor
QuoteDisplay MoreLaw Banning Fish Tattooing Unenforceable.
October 15, 2007
OKLAHOMA – The Oklahoma City Council upheld a law barring the artificial coloring of fish this week.
The law was challenged after a pet store owner who was found selling fish with “I love you” tattooed on their scales. The fish came from Quality Pets of Oklahoma. Company owner Don Fleming said his fish are dyed using the same techniques as the major chains – like Petco, PetSmart and Wal-Mart – which involves injecting the color into the fish or dying them in a dye bath.
Fleming says he was forced to relinquish about $1,700 in fish. So he went to Oklahoma City Councilman Gary Marrs to have the law challenged.
That's when Cynthia Armstrong, state director of the Humane Society of the United States stepped in.
Armstrong contends that artificial coloring is inhumane – whether by dying or injection. She also said that even dye baths – which are legal – are damaging because the fish drink the chemicals. This can lead to high mortality rates and weakened immune systems for those that survive.
But Fleming disagrees with that level of severity. Unfortunately, there's no definitive research on the subject to tip the scales in either direction.
City Councilman Pat Ryan was the sole objector to the compromise – which would continue to allow dye baths. That's because its difficult to tell what method was used for coloring.
But the other seven council members decided to maintain the compromise. That's because Quality Pets employs 115 people – and taking those jobs away is not in the city's best interest.
Pretty sick IMO.