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Long-term, high accuracy seawater temperature data sets are essential in studies assessing environmental changes that may alter coral reef communities. Located at the approximately the same latitude, the subsurface seawater temperature (S3T) off Discovery Bay, Jamaica (DBJ) and the U.S. Virgin Islands (USVI) had the same overall mean temperature. The USVI S3T during the winter months is approximately 0.5 degrees C warmer than DBJ, while May - July at DBJ is approximately 1 degrees C warmer than USVI S3T. With the passing of tropical storms in 1995 and 1997 in the USVI S3T dropped as much as 1.5 degrees C within a 20 hr period and did not revert to the previous temperature during that calendar year. Mean monthly S3T during 2000 and 2001 in the USVI was > 0.5 degrees C warmer than during similar periods in the early 1990s. Mean monthly S3T during 1999-2002 at DBJ was 0.27 degrees C cooler than during 1994-1995.

Puerulus settlement of the western Atlantic spiny lobster, Panulirus argus, was monitored using modified Witham collectors from December 1996 to March 1998 at seven sites around St. Thomas, U.S. Virgin Islands. A total of 605 pueruli were collected from 553 samples for a catch per unit effort (CPUE) for all sites of 1.09 pueruli. The greatest settlement occurred on sites within a recently declared marine reserve, which had an overall CPUE of 1.77 pueruli. Settlement in non-reserve sites was much lower with an overall CPUE of 0.31 pueruli. Pueruli recruitment declined 67% at inshore sites and 53% at offshore sites between July 1992 - April 1994 and February 1997 - March 1998. Also, only 10% of months sampled in 1997-98 had a CPUE > 0.5 compared to 55% in a previous study in 1992 - 1993. Despite the decline in pueruli CPUE in 1997-98 compared to 1992-94, the commercial lobster catch in the 2000-01 fishing season, and by inference the adult lobster population (legal lobster size in the US Virgin Islands is > or = 3.5 cm carapace length), remained stable.