Semen was collected from three mature male alligators in mid-April 3 and 5 days following intramuscular administration of 40 mg 17-methyltestosterone. Mammalian rectal electroejaculation probes were placed in the cloaca to stimulate movement of semen. The penile groove was catheterized and semen collected by aspiration. Electroejaculation resulted in drainage of 5-30 cc of a clear fluid from small accessory ducts on the lateral surface of the shaft of the penis. Small samples of semen from each alligator and from the pooled semen were placed in aliquots of minimal essential media (MEM), Lactose at 330 mOsm in 20% egg yolk (LAC), BES or N,N-bis(2-hydroxyflethyl)-2-aminoethane sulfonic acid buffered with Tris to pH 7.1 at 330 mOsm in 20% yolk (BST). Minnesota Turkey Growers semen extender (MTG), and accessory duct fluid (ADF). Initial motility in all samples was below 50% but improved on standing for one hour. After 24 hours at 5C, all samples except BST were reduced to less than 5% motility, with LAC and MTG at 0 per cent. BST motility varied from 30 to 80% up to 48 hours post-collection. Oscillation of sperm cells was seen for up to 5 days in ADF and 7 days in MEM. ADF caused agglutination of alligator spermatozoa. Vigorous motility of up to 25% was maintained for 11 days in BST.