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FIG. 6. A 3.9 m (12' 11 1 / 2") American Alligator was a center of attractionin the 1898 reptile house.mained unknown until they grew to adult sizes and displayed whatmight be construed as male behavior. Mature males might be identified,but the identification of females often remained dubious.Animals that might have been maintained for years in the hope offuture reproduction might ultimately be found to be of the samesex. When Brazaitis arrived as a keeper in the reptile house (1954),the main west pools housed four large alligators, acquired in thehope that they constituted two breeding pairs. As they grew insize, their incessant combats led to their medication with hormonesin an effort to reduce their belligerence. The animals were eventuallydisposed of to an animal dealer and the main pools were thendedicated to holding the array of crocodilian species that wereaccumulating.Fig. 8 shows the northeast pool and two Indian Gharial, Gavialisgangeticus. The animal in the foreground lacks a lower jaw andwas the oldest crocodilian in the collection, having been purchasedfor $100 from an animal dealer in 1946. Its importance as a rarespecies was immediately recognized. Measuring 116 cm on arrival,the animal was presumed to be a female. In 1954, at about178 cm in length, the animal damaged its lower jaw in a gate accidentand the lower jaw was amputated immediately anterior to themandibular symphysis, at about the 20 th mandibular tooth. Thereafter,all feeding had to be accomplished by a keeper using a longforceps, holding food in the animal’s mouth until it could be swallowed.The animal thoroughly learned the technique and trainedmany new keepers, including Brazaitis, in its use. It died of unknowncauses in 1974 at a length of 295 cm, having been in thecollection for about 28 years. The second animal in Fig. 8 is oneof four animals acquired around 1952, for the future opening ofthe newly renovated Reptile House. The sex of these animals wasunknown, and all eventually perished from causes of undeterminedetiology. Not until 1985, with the opening of Jungle World in theWild Asia exhibit at the Bronx Zoo was the species exhibited again.five sub-adult gharial from Orissa, India, were added to the collection,to become the nucleus of a future captive breeding programfor this critically endangered species.Still, by 1954, there was no plan for breeding crocodilians. Itwas not until 1963 that a reliable method of sexing crocodiliansFIG. 7. Outdoor summer pool for crocodilians with a crocodile at thefar right. About 1930. From the Bulletin of the Society.was discovered at the Reptile House (Brazaitis 1969), when fiveAmerican Alligators were placed on their backs and compared forany sexual dimorphism. The management of crocodilian collections,planned reproduction, and the interpretation of behaviorswas now possible.However, breeding potential was still haphazard. Most crocodiliansdied well before maturity due to dietary deficiencies orconflicts with larger animals as they approached adulthood. Rapidlygrowing juvenile crocodilians often suffered developmentalanomalies. For food, zoos generally provided only those speciesof fish that were commercially available in human food markets,and it was yet unknown that certain fatty saltwater species, particularlyafter being frozen and thawed, were detrimental to crocodilians,prohibiting the absorption of critically needed vitaminsand minerals, and adversely affecting fertility. Frozen saltwaterfish, horsemeat, liver and heart meats, as well as all vitamin supplements,were removed from all crocodilian diets beginning in September1979 and replaced with fresh-killed whole rodents, poultry,and live freshwater fish. In addition, color-corrected and ultravioletlighting regimens, developed by Townsend and Cole(1985) at the American Museum of Natural History for enhancingreproduction of parthenogenic lizards, were applied to hatchlingand rapidly growing crocodilians and proved equally successful.The management changes precipitated an unparalleled era of reproductivesuccess.Golden Age of Discovery in Crocodilian ScienceOur ignorance of crocodilian behavior and reproductive biologywas quickly being dissipated by a cadre of new scientists,inspired by awareness of the plight of threatened and criticallyendangered species. We had been working in the “dark ages” bythe “seat of our pants,” and there seemed to be no time left asspecies populations were designated by the international communityas either threatened or endangered.Ted Joanen, of the Louisiana Department of Fur, Fish and Game,was perhaps one of the most forward and practical thinkers of thetimes in conservation biology. Joanen understood the need forendangered species to have value if they were to be preserved forfuture generations, and he also set about developing management140 Herpetological Review 39(2), 2008