The destructive capacity of coastal storms is well known; it is not generally known that, in some places, storms may be the principal agents of coastline construction. This capability of storms can be demonstrated along the coast of northern British Honduras, which is on the southern edge of the Caribbean storm track and is struck by periodic hurricanes and lesser storms.

The coastline of British Honduras is a complex of lagoons, mangrove marshes, and barrier ridges. Comparison of individual lagoons indicates an evolutionary sequence as tidal deltas grow into the lagoon from the rear edge of the barriers. Other, less active, sedimentary processes are: (1) filling of the lagoon with mud and shell debris, (2) encroachment by mangrove marshes, and (3) gradual elevation of mudflats. Together, these processes represent "normal" conditions.

Numerous abandoned tidal deltas occur along the barriers. In these deltas, the seaward mouth of the tidal channel has been blocked by barrier ridges. Thus, the construction of barrier ridges represents an additional process which, at least locally, is able to upset the balance of forces responsible for the construction of tidal deltas. Major storms can be shown to be the cause.

Scattered, newly formed beaches composed of soft, black, H₂S-rich mud occur in small bights along the coast. At Northern River Lagoon, the sequence, from top to bottom, of black mud (18 in.), flotsam (2 in.), and clean quartz sand (at least 4 ft) indicates that the beaches did not accrete slowly, but formed during a single event. As these beaches do not appear on photographs taken in 1944, the most likely event is Hurricane Hattie, which struck the coast in 1961.

At Midwinters Lagoon, a well-developed tidal channel, open in 1944, is now blocked by a beach at least 100 ft wide with ridge-and-swale topography. If colonized by mangrove, this beach probably will become a permanent addition to the barrier ridges.

The development of the British Honduras coast can be understood only by considering both "normal" and "catastrophic" events. The complex interplay of all agents must be appreciated.

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