The Ostional National
is located in the counties of Santa Cruz and Nicoya in the province of
Guanacaste. It is bounded on the North by Punta India 222550 N - 34750
E (Hoja Cerro Brujo 3046-II), the South by Punta Guiones Nosara 210400
N - 353150
E (Hoja Garza 3045-I) and extending three miles out to sea. The refuge
comprises an area of 300 Ha on land and 800 Ha of ocean.
The Ostional Wildlife Refuge protects marine turtle
species, such as the Olive Ridley (Lora) and Leatherback (Baula) at
Ostional on the Nicoya Peninsula Costa Rica. Arribadas at this beach
considered the largest in the world, with as many as a million sea
eggs laid in the beach nesting areas each year.
Some days or weeks
before an expected
"arribada", one may observe an increasing number of turtles swimming
offshore. This is then the gathering of this particular group of
that will be taking part in the next event. As an individual will nest
four and six times a year, there will probably be females present that
in the previous "arribada".
Location and Directions
Wildife Refuge can be reached from either Nosara or San Juanillo. See
Road Map above. Tour guides are available in Nosara.
The Ostional National
was officially created in 1984 but was declared a protected area in
The refuge was initially construed as being 200m wide from Punta India
to the mouth of Rio Nosara. This area was increased to include the 200m
strip to Punta Guiones in 1985. Finally, in 1992, with the institution
of the new "Wildlife Law", came the final definition of the refuge
and in 1993 the amplification to the three mile maritime limit as it is
The best time to
visit Ostional is
just before and during an ARRIBADA. These occur, as a general rule, at
the start of the LAST Quarter MOON. The best months to see the biggest
ARRIBADAS are between July and December.
After an undetermined
waiting time, close
to the last quarter of the moon cycle, the "arribada" will begin. At
a few hundred turtles will come out on the beach, followed by a steady
of animals for the next three to seven days.
So many turtles come
onto the beach
in a short time span that most of the first nests are destroyed by
turtles. Therefore, in 1987, a project was initiated to allow local
the right to collect and sell a percentage of the eggs from the first
days of each arribada. This is the only place in the world where it is
legal to harvest turtle eggs. This practice is designed prevent
and to help the local community.
all through the year, at least once a month and, in some months, may
twice. The months between June and December, during the rainy season,
larger "arribadas". That means that the number of nesting turtles may
in the range of hundreds of thousands as opposed to tens
of thousands for the dry season months.
Park Facilities and Hours
ranger station at Playa Ostional is open from 8 am to 4 pm. Guided
are available with bi-lingual park employees. Contact the ADIO
de Desarrollo de Ostional) for more information. 506-682-0470 Costa
National Wildlife Refuge
was created to protect one of the world's most important nesting
of the marine turtle Lepidochelys olivacea (Olive Ridley) or Lora as it
is known locally.
1994, the functions of the forestry
service, the park service and the wildlife service were combined under
the umbrella of the "National System of Conservation Areas" (SINAC)
directly responsible to the Ministry of the Environment and Energy
this system, the Refuge falls
under the control of the "Tempisque Conservation Area" (ACT)
which has a wildlife ranger as its representative in Ostional.
nesting beaches are patrolled
by guards who are paid by the village of Ostional.
As marine turtles
are normally shy and easily disturbed when nesting, the "arribada" is
the more exciting and strange. These animals, now in "arribada mode",
come out during the night and day and be almost oblivious to
by man or animal, light or sound. Bumping into each other, crawling
each other, they are automatons on their way to fulfil a predetermined
lay their eggs at all cost.
"arribada" thus far recorded in Ostional, took place in November 1995
when a calculated 500 000 females came ashore.
Olive Ridley Sea Turtles of Ostional National Wildlife Refuge in Costa
are world famous for their arribadas, huge egg laying seasons. The
nesting beach at Ostional can be covered with thousands of turtles
during an arribada. Although some believe that arribadas may be
correlated with moon phases and
tides, there are turtles laying eggs at Ostional Beach throughout most