7.1 Introduction
Venezuela is located in northern South America between 00°45
0 and 15°40
0 N, and
between 59°47
0 and 73°22
0 W (Fig. 7.1). Its coastal waters include the Caribbean
Sea and the west central Atlantic Ocean, which gives it a special biogeographical
position. Ecosystems in the Caribbean Sea include sandy beaches, rocky shores,
seagrass meadows, coral reefs, coastal lagoons, soft bottom communities and
mangroves, which results in a high environmental variability as a consequence of
periodic coastal upwellings due to the trade winds. The Atlantic zone is mainly
influenced by the Orinoco River which flows north towards the Caribbean Sea and
promotes a brackish water environment in the coastal areas of its delta and the
Gulf of Paria, a situation that increases the environmental variability. On the other
hand, the 3,964 km coastline (68 % in the Caribbean Sea, 21 % in the Atlantic
Ocean and 11 % in the islands) is very diverse both in geology and topography,
and a great diversity of geomorphologies coexist including brackish lakes,
lagoons, bays, peninsulas and other geologic formations. Such environments,
together with 14 archipelagos, encompass multiple ecosystems resulting in one of
the most diverse areas in the world (Aguilera et al. 2003; Miloslavich et al. 2005;
Miloslavich and Klein 2008).
Sea surface temperature (SST) along the Venezuelan coastline is mainly
affected by upwelling, and presents yearly ranges between 20 and 29°C with daily
maximum variations of 2.5°C (Penchaszadeh et al. 2000). There are 12 upwelling
zones that could be identified along the Venezuelan coast using images from the
‘‘Advanced Very High Resolution Radiometer (AVHRR)’’ to determine the SST.
In western Venezuela, the upwelling zones are located to the east of the Guajira
Peninsula; in the Gulf of Venezuela and in Punto Fijo coast, western Paraguaná
Peninsula; in Cabo San Román and in Puerto Cumarebo, eastern Falcón state.
Upwelling is not frequent along the central coast of Venezuela. There are several
upwelling systems in the eastern coast between Puerto La Cruz and Cumaná, to the
north of the Araya Peninsula and Margarita Island, and the central coast of Sucre
state, near Carúpano. Coastal upwelling is frequent in all these locations, associated with the relatively high speed and predominance of the trade winds during the
first 6 months of the year. The intensity and propagation of the upwelling is
considerable and extends beyond 2,00,000 km
2 , contributing to establish the most
productive zone of the Caribbean Sea. Offshore from the Paria Peninsula and to the
north of the island of Trinidad, upwelling occurs during limited periods of variable
intensity. The cold water masses occasionally form eddies that migrate northeast,
probably due to the movement of less dense warm water masses from the Gulf of
Paria (Müller-Karger and Varela 1989; Penchaszadeh et al. 2000).
All these characteristics that result from environmental variability in the
Venezuelan coasts have allowed the establishment of 13 ecoregions according to
their ecological, physical and oceanographic characteristics (Fig. 7.1; Miloslavich
and Klein 2008).
236
C. Lodeiros et al.
Venezuela is located in northern South America between 00°45
0 and 15°40
0 N, and
between 59°47
0 and 73°22
0 W (Fig. 7.1). Its coastal waters include the Caribbean
Sea and the west central Atlantic Ocean, which gives it a special biogeographical
position. Ecosystems in the Caribbean Sea include sandy beaches, rocky shores,
seagrass meadows, coral reefs, coastal lagoons, soft bottom communities and
mangroves, which results in a high environmental variability as a consequence of
periodic coastal upwellings due to the trade winds. The Atlantic zone is mainly
influenced by the Orinoco River which flows north towards the Caribbean Sea and
promotes a brackish water environment in the coastal areas of its delta and the
Gulf of Paria, a situation that increases the environmental variability. On the other
hand, the 3,964 km coastline (68 % in the Caribbean Sea, 21 % in the Atlantic
Ocean and 11 % in the islands) is very diverse both in geology and topography,
and a great diversity of geomorphologies coexist including brackish lakes,
lagoons, bays, peninsulas and other geologic formations. Such environments,
together with 14 archipelagos, encompass multiple ecosystems resulting in one of
the most diverse areas in the world (Aguilera et al. 2003; Miloslavich et al. 2005;
Miloslavich and Klein 2008).
Sea surface temperature (SST) along the Venezuelan coastline is mainly
affected by upwelling, and presents yearly ranges between 20 and 29°C with daily
maximum variations of 2.5°C (Penchaszadeh et al. 2000). There are 12 upwelling
zones that could be identified along the Venezuelan coast using images from the
‘‘Advanced Very High Resolution Radiometer (AVHRR)’’ to determine the SST.
In western Venezuela, the upwelling zones are located to the east of the Guajira
Peninsula; in the Gulf of Venezuela and in Punto Fijo coast, western Paraguaná
Peninsula; in Cabo San Román and in Puerto Cumarebo, eastern Falcón state.
Upwelling is not frequent along the central coast of Venezuela. There are several
upwelling systems in the eastern coast between Puerto La Cruz and Cumaná, to the
north of the Araya Peninsula and Margarita Island, and the central coast of Sucre
state, near Carúpano. Coastal upwelling is frequent in all these locations, associated with the relatively high speed and predominance of the trade winds during the
first 6 months of the year. The intensity and propagation of the upwelling is
considerable and extends beyond 2,00,000 km
2 , contributing to establish the most
productive zone of the Caribbean Sea. Offshore from the Paria Peninsula and to the
north of the island of Trinidad, upwelling occurs during limited periods of variable
intensity. The cold water masses occasionally form eddies that migrate northeast,
probably due to the movement of less dense warm water masses from the Gulf of
Paria (Müller-Karger and Varela 1989; Penchaszadeh et al. 2000).
All these characteristics that result from environmental variability in the
Venezuelan coasts have allowed the establishment of 13 ecoregions according to
their ecological, physical and oceanographic characteristics (Fig. 7.1; Miloslavich
and Klein 2008).
236
C. Lodeiros et al.