Damage to the leeward reefs of Curac¸ao and Bonaire, Netherlands Antilles from a rare storm event: Hurricane Lenny, November 1999
Fringing reefs along the southwestern shores of the Caribbean islands of Curaçao and Bonaire (12°N), located outside the most frequent hurricane tracks, are rarely affected by heavy wave-action and major storms, yet have experienced disturbances such as coral bleaching, coral diseases, and mass mortalities. The last major hurricane to hit these islands occurred over 100 yr ago. In November 1999, Hurricane Lenny took an unusual west-to-east track, bisecting the Caribbean Basin and passing approximately 200 miles north of Curaçao and Bonaire. The leeward shores of both islands were pounded for 24 h by heavy waves (~3–6 m) generated while the storm was centered far to the west. Reef damage surveys at 33 sites conducted between November 1999 to April 2000, following the storm, documented occurrences of toppling, fragmentation, tissue damage, bleaching, and smothering due to the storm. Reefs were severely damaged along westward-facing shores but less impacted where the reef front was tangential to the wave direction or was protected by offshore islands. At the most severely damaged sites, massive coral colonies 2–3-m high (older than 100 yr) were toppled or overturned, smaller corals were broken loose and tumbled across the shallow reef platform and either deposited on the shore or dropped onto the deeper forereef slope. Branching and plating growth forms suffered more damage than massive species and large colonies experienced greater damage than small colonies. Toppled massive corals have a high potential of preserving the event signature even if they survive and continue to grow. Reorientation of large, long-lived coralla may provide a unique indicator of disturbance in a reef system rarely affected by hurricanes. At some locations, wave scouring removed loose sediment to reveal a cemented framework of Acropora cervicornis rubble on the shallow platform above 10-m depth. This rubble was generated in situ, not by storm processes, but rather by an earlier mass mortality of thickets of staghorn coral that covered extensive areas of the shallow platform prior to the incidence of white band disease in the early 1980s.