Résumé
The performance of two types of tags (external tags and visual implants) on juvenile tarpon is evaluated in mangrove mud flats of Boquerón Bay. External tags (mini-spaghetti and dangling tags) yielded high retention and recovery rates (69% and 46%, respectively) over a period
of 167 d. While recapture returns with visual implants were lower (26%) than returns with external tags, they provided more reliable estimates of growth. Experiments conducted between July 1992 to February 1995 suggest juvenile tarpon residency in Puerto Rican mud flats is ephemeral: limited
to a few months when high water connection exist among mud flats and the adjacent lagoon (from June to February). Tarpon are recruited as late larvae or newly metamorphosed juveniles during this period. Recruitment exhibited a high inter-annual variation; highest from August to September in
1992 and from October to December in 1994, while it completely crashed during 1993. Tarpon juveniles grew at 1.2% their SL d−1 and reached a maximum sustainable size of approximately 200 mm SL between the months of October to December. Most exit the area before the end of
February before the mud flats become completely dry.