Effects of Cyanide on Coral Reefs (exerpt from Rubec 1987)
According to Robinson, if dynamite is the "one" in the one-two punch, cyanide may be the knock-out blow (McLarney 1985a,b). While dynamite kills some animals directly, it does mostly structural damage and leaves enough living coral to repopulate the reef eventually. With many large corals reduced to rubble, surviving food fishes desert a dynamited reef, but smaller aquarium fish hang on surprisingly well. A blasted reef does not have the beauty of a pristine coral reef environment, but as long as there is enough living coral, many of the angelfishes, damsels, butterflyfishes, clowns etc. will be there.
The best demonstration of the one-two punch is the Danajon Bank, which occupies much of the 24 to 32 km wide, 97 km long Bohol Strait, between the Islands of Bohol and Cubu (McLarney 1986). One of the greatest coral reef complexes in the world in terms of extent and, until recently diversity, it has fed the people of Bohol and Cebu for centuries.
The decline of the Danajon Bank began in the fifties with heavy dynamite usage (McLarney 1986). Yet, in the sixties when Gonzales, operating out of Cebu, pioneered the cyanide method, the Danajon, even after a decade of blast fishing, represented a bonanza for the entire aquarium fish trade. Af first Gonales had a monopoly, but it didn't take other collectors long to scope out his sites-and his methods-and Cebu became a major center of the business.
From an underwater perspective, the Danajon Bank is a disaster area (McLarney 1986). In many places, acres of corals have been toppled and shattered by explosions. Most of these prostrate corals, their standing fragments and even the remnants of structurally intact corals are dead and covered with algae. Robinson recounts instances of diving for a mile, in a straight line, and not seeing a single marketable fish. Dynamite broke up the structure of the reef, wrecked the esthetic and dispersed the food fish, but Robinson believes it was cyanide, patiently and repeatedly applied to one coral head after another, which erased not only aquarium fishes, but virtually the entire support system from small to large fishes.
Robinson (1984c) noted that each cyanide collector squirts about 50 coral heads per day and dives about 225 days per year. He estimates that there are 600 full time collectors and about 400 seasonal collectors (McLarney 1986). A simple extrapolation indicates that 1000 colletors blitz about 11 million coral heads per year or about 240 million coral heads ove the past 20 years. While it is not certain what the rate of mortality of coral heads is from being squirted with cyanide, the figures give some idea of the potential magnitude of the problem.
Robinson (pers. comm. 1985) maintains that it is possible to distinguish between coral heads which have been dynamited and those which have been blitzed with cyanide. Coral heads exposed to cyanide are usually dead, but retain intact coral skeletons, while corals which have been dynamited are fragmented. Robinson observed dead coral heads forming bare patches in reefs, down to a depth of 25 m. Many of the dead reefs were in isolated areas, far from river mouths and other sources of pollution. The types of coral heads preferred by marine fish in high demand by aquarists, were generally the ones which were dead, presumably due to the use of cyanide. Fish collecting with sodium cyanide (NaCN) affects those specific types of coral heads which provide shelter and spawning sites for coral reef aquarium fishes.
McLarney, W.O. 1985a. Diving with cyanide. Outside Magazine, Sept. p. 11-12.
McLarney, W.O. 1985b. Scandal in the saltwater aquarium trade, Philippines coral reefs dosed with cyanide. Not Man Apart, Nov.-Dec., p. 18-19.
McLarney, W.D. 1986. Collecting coral reef fishes in the Philippines: Information and analogue. Scientists debate: more reefs, more fishes die. Annals of Earth (Part 2 of 3) 4(2): 16-20.
Rubec, P. J. 1987. The effects of sodium cyanide on coral reefs and marine fish in the Philippines. Marine Fish Monthly 2(2) and 2(3).
Remember it was YOU who miss read the article and belived the article stated no FOOD fish where found, or it implied that. 
