FIELD AND LABORATORY OBSERVATIONS ON LARVAL ATLANTIC SAILFISH (ISTIOPHORUS-PLATYPTERUS) AND SWORDFISH (XIPHIAS-GLADIUS)

We conducted a 2-year study off Miami, Florida, to verify the presence and seasonality of larval billfish, particularly sailfish (Istiophoru s platypterus) and swordfish (Xiphias gladius), and, to examine the fe asibility of obtaining laboratory observations on feeding, behavior, a nd growth. The Gulf Stream's western edge was sampled from April to Oc tober 1994, and from March to October 1995, with a 1-mm-mesh plankton net. A total of 315 samples yielded 288 larval sailfish and 2 larval s wordfish. Sailfish larvae were present from May to October with a May to July peak, while the two swordfish were captured in May and July. H ighest sailfish catches were made from 07:00 to 08:00. No swordfish su rvived capture at sea. Of the 288 sailfish larvae captured, 87 were al ive immediately after capture and these were transported to the Univer sity of Miami's experimental hatchery. Of the sailfish captured alive, 23 survived 24 h, 7 survived 48 h, and 1 survived 72 h. Dissection co nfirmed that one larval sailfish ingested Artemia introduced as food. This is the first reported observation of larval sailfish feeding.