<span name="style_bold">Spatial and temporal distribution of physicochemical features in the habitat of whale shark </span><span name="style_italic">Rhincodon typus </span><span name="style_bold">(Orectolobiformes: Rhincodontidae) in the north of Mexican Caribbean</span>. Large groups of whale sharks (<span name="style_italic">Rhincodon typus</span>) are common in the North Mexican Caribbean and gather between May and September each year<span name="style_italic">. </span>We describe their spatial and temporal distribution, and the physicochemical (temperature, dissolved oxygen, light extinction coefficient and salinity) and biological conditions during the presence and absence seasons of <span name="style_italic">R. typus. </span>A total of 26 sampling stations were monitored to record whale shark sightings and physicochemical variables during 10 field campaigns from April 2005 to March 2006. At each station, zooplankton and water samples, for chlorophyll-a and nutrients determination, were collected. Physicochemical conditions were significantly different between presence-absence seasons (ANOSIM, Rglobal = 0.632). The <span name="style_italic">R. typus </span>season was characterized by low salinity values, and higher temperature, chlorophyll-a, dissolved oxygen and inorganic nitrogen concentrations values. Average zooplankton biomass was lower during the absence season, while recorded the maximum values during the presence one. Furthermore, these values were also observed in areas with higher species abundances, supporting the hypothesis that the site is used by <span name="style_italic">R. typus </span>primarily as a foraging area. We conclude that physicochemical conditions of the study area promote the biological productivity, which explains the spatial and temporal variability of <span name="style_italic">R. typus</span>. Rev. Biol. Trop. 58 (1): 399-412. Epub 2010 March 01.. Rev. Biol. Trop. 58 (1): 399-412. Epub 2010 March 01.

Mexican Caribbean; Rhincodon typus; surgencia; hábitat; patrón de distribución; Caribe Mexicano