First Weeks at Ostional Wildlife Refuge

Greetings from Ostional National Wildlife Refuge in Costa Rica!  I’ve been working here for a few weeks and it’s been a great experience so far.  The Refuge is located in the small town of Ostional, on the northwestern Pacific coast of the country.  This protected area was created in 1983 by the Costa Rican government to preserve a major nesting site of the Olive Ridley Sea Turtle (Lepidochelys olivacea).  I found out about this project by emailing a supervisor in charge of the Guanacaste Conservation Area, who put me in touch with one of the researchers in charge of the work in Ostional, who offered me the opportunity to be an intern for the summer here.

The Olive Ridley Sea Turtle is distributed worldwide in tropical areas and Ostional is the largest nesting area for this species of sea turtle in Costa Rica.  The Olive Ridley is famous for the phenomenon of mass nesting, called arribadas, although two other species of sea turtles, the Leatherback (Dermochelys coriacea) and the Green (Chelonia mydas) sea turtles, also nest here.  The refuge spans 18 kilometers (11 miles) of coastline, extending 200 meters (700 feet) onto land, and 6 kilometers (3 nautical miles) out to sea.

Sunset at Ostional Wildlife Refuge

The majority of my work takes place at night, when the turtles come up on the beach to nest.  To get an idea of what a nesting turtle does, here is a video produced by WWF.  Along with other staff members, I lead groups of volunteers on nightly beach patrols to find nesting turtles and record their location and size, the number of eggs they lay, the size of the nest, the time it takes for the turtle to lay the eggs, among other data.  Finally, we tag the turtle so that we can keep track of her, if she comes back to nest in Ostional.  During the day, we excavate and exhume nests to examine the eggs and determine how many turtles hatched from each nest and what stage of development the unhatched eggs reached before death.  Additionally, we perform a weekly beach clean up and coordinate hiking trips for the volunteers who come to the refuge.  Most of the volunteers do not speak Spanish and many of the workers do not speak English, so my duties include quite a bit of translation.  In my free time, I give English lessons to several of the staff members and their children, as well as enjoy the beautiful beach.

A turtle returning to the ocean during a recent arribada

My first week here consisted mainly of training and getting to know the staff here at Ostional Wildlife Refuge.  I spent about a week being taught how to lead groups on the turtle patrols and about all of the procedures in place here.  I also had a lot of time to get to know the staff here at the refuge.  About a dozen or so people are working here at any given time, including researchers, park rangers, research assistants, and the cook, in addition to the constantly rotating groups of volunteers.  I hope to continue to learn a great deal this summer from the staff here at the refuge.  Most of them have lived in Ostional their whole lives and have a lot to teach me.  I’m also hoping to witness a large arribada as the rainy season continues.  The organization I’m working with is vital to the conservation efforts of this sea turtle species, and I’m looking forward to continuing my work here.

– Sarah Steele ’13

7 thoughts on “First Weeks at Ostional Wildlife Refuge”

  1. Wow, this internship sounds very interesting! Do you find turtle nests every night? Until when will the turtles be laying eggs and how long does it usually take for them to hatch?

  2. Your internship sounds amazing! I was wondering how you tag the turtles and what are some of the other wildlife that your organization mainly focuses on for preservation?

  3. Steele- I’m so glad this is working out well for you! Your organization sounds awesome and I can’t wait to hear more about your experiences. Just curious- What happens to the eggs that never hatched once you’ve gotten your data?

  4. Hi Nicole!

    The Olive Ridley sea turtle lays eggs year round and there are turtles nesting almost every night of the year, although many of the turtles concentrate their efforts during the arribadas (mass-nesting events). It takes between 45-55 days for the eggs to hatch, depending on the temperature. Although the turtles nest year-round, hatchlings only survive from eggs laid during the rainy season (Oct-Nov) because of the lethally high temperatures during the dry season.

    Thanks for the questions!

  5. Hi Ash!

    Thanks for the comments and support! Only about 8% of the eggs actually hatch — the rest are consumed by predators or are otherwise rendered infertile. Most of the eggs end up rotting in the sand and are eventually eaten by crabs, insects, vultures, and/or bacteria.

  6. Thanks for the great questions! We mark the turtles using small numbered metal tags and an applicator which we use to insert the tags on both of the turtles’ front flippers. This process is somewhat similar to piercing an ear and doesn’t hurt the turtles in any way.

    The organization I work for mainly focuses on turtle research and conservation, but is also concerned with the other organisms that make up the beach ecosystem. For instance, we often take in injured seabirds so that they can be treated by the local veterinarian.

  7. I was searching the internet for stuff about Ostional and this came up! It’s so great to read all of your blogs from Ostional! I hope that you are doing well, and that you found adventure and fun after I left! Hopefully, no more stingray stings?
    Hope our paths cross again some day! Good luck in your bright future!

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