During the PIT Program’s capture and tagging of juvenile lemon sharks, 3 days were set aside to longline for larger sharks. In the days surrounding the new and full moon, the extreme tides make it difficult to conduct our gillnetting sessions. So for these days, from June 16 – 19, we set 5 lines around the islands to survey the larger sharks. The data collected during the PIT longline set also contributes to our bi-monthly longline survey.

Analyzing the catch data from our longline sets provides valuable information as to the habits, behavior, survival rates, growth rates, movement and migrations of the sharks around Bimini. Seasonal and monthly changes in the longline catch also provide valuable insight into the life history of Bimini’s sharks.

During PIT, we set 4 lines in the main lagoon and put the 5th line extending south from the Sharklab boat channel.

BBFS Longline Catch for PIT 2004 Total Length of Shark measured in centimeters
June 16 115 Lemon Shark 252 Nurse Shark 215 Nurse Shark 141 Lemon Shark 117 Nurse Shark	June 17 137 Blacktip Shark 125 Blacktip Shark 237 Bull Shark 216 Tiger Shark 213 Nurse Shark 229 Nurse Shark 140 Blacktip Shark	June 18 144 Blacktip Shark 232 Lemon Shark 123 Lemon Shark 232 Nurse Shark 214 Nurse Shark 181 Lemon Shark

During June, Nurse sharks are often the most common species seen on the lines, many of which are mature males. This increase in occurrence coincides with the mating season for Nurse sharks around Bimini. During the month of June, and into July, the BBFS has witnessed several Nurse shark mating pairs. Seven nurse sharks were caught during PIT this year, one of which was caught twice in two days.

Another interesting finding on the lines was a large female bull shark caught just south of the BBFS. The individual had fresh mating scars, which indicates that May-June is mating season for the Bull sharks of the Bahamas. The mating of the Bahamas bull sharks is likely to occur around the coasts of Florida, marked by an abrupt absence of bull sharks in the Bahamas starting in late April, and a large increase in Florida’s bull shark population around this time.

Most of the lemon sharks caught were sub-adults. By looking in our data base, we were able to discover that the 232 cm lemon shark caught on the 18th was the same shark that Bryan caught off the BBFS dock at the end of 2003. The last lemon shark we caught during this set was 181 cm, and again by looking in the data base, we found that this shark was originally tagged in PIT of 1997, when it was just 62 cm long. Recapturing sharks such as this one lend strong proof of how valuable the efforts of the BBFS PIT Program are in tracing the life history of Bimini’s lemon sharks.