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Observations of two of the endemic species of lizards of Malpelo Island provide new information on their natural history, ecology, and population size. Anolis agassizi, the most abundant and broadly distributed lizard, feeds mainly on insects and excrements of marine birds. It sleeps on large rocks, surfaces on hills or on man-made structures and, although it does not defend perch sites like most Anolis do, it does show preferences for high perches where, among other activities, it carries out copulation. Diploglossus millepunctatus, the largest and least abundant lizard, is an opportunistic-predator and scavenger that has a remarkable relationship with the land crab of the island (Johngarthia malpilensis) which it not only eats, but also competes with it for food. Behavior, higher density, larger body size and weight of individual D. millepunctatus living close to cabins suggest that these lizards accommodate to the presence of people by feeding on left-over food.

The trophic ecology of Nazca Booby was evaluated through the analysis of gut contents collected between September 2004 and July 2005 during five field trips. From 110 induced regurgitation samples, the diet was analyzed using the variables number, weight and frequency of occurrence of the different nutritious categories, and using the distribution of the frequencies of sizes of preys at general, intraspecific and temporal levels. Oxyporrhamphus micropterus (halfbeaks fishes, family Hemiramphidae) and fishes of the family Exocoetidae (flying fishes) were the principal components found on the diet, followed by fishes of the families Carangidae and Escombridae. Variations were present in the consumption of the distinct categories at general, intraspecific and temporal levels, with the strongest differences in the consumption of preys of the family Hemiramphidae. The quantity of food taken by S. granti at Malpelo Island showed close relation with its reproductive cycle, and it adjusted to the model of energetic demand proposed for marine birds. Comparisons with other analogue studies showed slight differences between localities, apparently related with the availability of preys. It seems like there is a niche partition between females and males of S. granti at Malpelo Island related with the quantity and sizes of the preys ingested, and in a lesser degree with the composition of the diet. The present work is the first one to evaluate in detail the diet of the Nazca Booby and considerably extends the geographical range of this kind of studies in the Eastern Pacific.

Tortuguilla is a small island off the southern portion of the Colombian Caribbean continental coast. It is surrounded by a shallow calcareous shelf which is overgrown by recent coral formations whose distribution, composition and zonation are herewith qualitative described for the first time. Observations and data collecting were conducted during  two days from a boat by snorkeling at 63 stations and along manta tow transects. Despite the reduced area and the adverse turbidity and sedimentation conditions, at least 16 species of stony corals were registered (4 more to be confirmed), being Millepora spp. and Siderastrea siderea the most common. Five different coral assemblages were recognized.