The Changing Coastline of the Cedros Peninsula, Trinidad

Abstract

The extreme tip of south-western Trinidad at Icacos has been the site of aggressive shoreline erosion and accretion over the past several decades. The effects of erosion are particularly noticeable at Coral Point, Constance Estate and accretion at Punta del Arenal. Anecdotal evidence suggests that the rate of erosion at Coral Point has accelerated over the past three decades. There are few readily identified landmarks of known age making it difficult to measure recession or progradation of the shoreline. The most prominent are the estate buildings at Constance Estate and the base of the navigational beacon beside the beach road leading to Punta del Arenal. Nevertheless, using details of the earliest comprehensive coastal survey map of 1797, the Mallet Map, the Cazabon painting of Columbus Bay dated 1857 showing the Los Gallos rocks, and aerial photography of Icacos Point in 1957 and 1994, it has been possible to estimate rates of erosion and accretion. At Coral Point the rate of recession is approximately 4.3m per year while that of progradation at Punta del Arenal is about 3m per year.

Evidence from the Mallet Map, the Cazabon painting and aerial photography indicates extreme change in the Los Gallos rocks over the past 200 years. It is suggested that the apparent acceleration at Constance Estate may be caused by continued natural erosion of the Los Gallos rocks permitting more violent longshore currents in Columbus Bay.