a coral reef that has been geologically pushed up and out of the sea. This also resulted in the natural fringing reef system seen today, in which the coral formations start at the shoreline. Tidal variations are only about , so the corals start at the low tide line and continue on, following the underwater topology of the island's base. Bonaire's tides are more affected by a combination of wind and low/ high-pressure systems than by the moon. The northern end of the island is relatively mountainous, although its highest peak (Brandaris) is only . The southern part of the island is nearly flat and barely rises above sea level. A significant portion of this southern region is covered with sea water in process of evaporation for salt production. This area also contains Lac Bay with its large mangrove forest. The shoreline of Bonaire is dotted with lagoons and inlets, the largest of which is Goto Lake in the north. These lagoons and wetlands provide an excellent habitat for a wide variety of shorebirds. Klein Bonaire, the small island in the sheltered lee of Bonaire, has the same geological history. While Bonaire has some hills and variations in altitude, Klein Bonaire's surface is quite level and just a few feet above high tide. Because the island is as yet undeveloped, the fringing reef system surrounding Klein Bonaire is truly pristine. The smaller island is entirely ringed with dive sites. Bonaire has a land area of , while Klein Bonaire is an additional . Washington Slagbaai National Park is an ecological preserve on the north side of the island. The highest point of Bonaire, Mount Brandaris, is tall and is located within this preserve. It has a complete view of the island. Climate Bonaire has a warm, dry (though humid) and windy climate. The average temperature is with a seasonal variation and daily variation. The ocean temperature around the island fluctuates between . The highest recorded temperature is and the lowest, . Nearly constant winds blow from the east with an average speed of . The humidity is very constant, averaging 76% and fluctuating between 85% and 66% on a daily basis. Average annual rainfall is , most of which occurs in October through January. Bonaire lies outside the hurricane belt, though its weather and oceanic conditions are occasionally affected by hurricanes and tropical storms. This semi-arid climate is conducive to