the coastline and main rocky islets
located on the island periphery.
 Sula dactylatra
 (Masked Booby) (Piquero
 enmascarado)
Observations: The colony previously
described by Montoya (2003) located
on the islet Dos Amigos Grande
continues to increase, and is now
estimated at 20 nesting pairs,
including immatures.
 Sula nebouxii
 (Blue-footed Booby) (Piquero de
 patas azules)
Observations: One mature adult was
seen during the circumnavigation of
island on the last evening (28ha). The
pale face and upper tail coverts and
blue feet were seen clearly. This
sighting confirms the accidental
presence of this species on the island,
as previously recorded only one time
(Montoya 2003).
 Sula leucogaster
 (Brown Booby) (Piquero moreno)
Observations: There are numerous
pairs with young nesting principally
on clumps of the endemic grass
( lil. -o paniculata, on the islets and
rocky outcroppings of the main island
in the north, northeast and northwest
(Cnica, Manuelita, Pjara, Cscara y
Roca Gissler).
 Sula sula
 (Red-footed Booby) (Piquero de
 patas rojas)
Observations: We observed this
species nesting in Clusia rosea trees
and perching especially on branches
of the endemic Cecropia pittieri, on


the islets of the north, northeast and
northwest of the island. This species
also nests in trees on the main island.
Downy white nestlings were
observed. This is the resident species
most heavily preyed upon by the
Great Frigatebird (Fregata minor),
also a resident species.
 Fregata magnificent
 (Magnificent Frigatebird)
 (Rabihorcado magno)
Observations: Several were seen
daily, both adults and immatures,
soaring amongst Great Frigatebirds.
They were observed particularly in
the northeast, north and northwest
sectors of the island.
 Fregata minor
 (Great Frigatebird) (Rabihorcado
 grande)
Observations: Numerous individuals
of varying ages were observed daily,
mainly in the northeast, north and
northwest sectors of the island. In the
vicinity of the islets Manuelita,
Conica and Pajara they were notably
preying upon Red-footed Boobies
(Sula sula), as recorded by Slud
(1967).
 Ardea herodias
(Great Blue Heron) (Garzn azulado)
Observations: One immature was
seen on the 26th on rocks by Wafer
Bay and on the 27th near the bridge
over Rio Genio (probably the same
individual). The presence of this
species on the island was first
recorded by Slud (1967) between
February and April 1963 at Wafer
Bay.