In 2000 ASVO started activities to promote sea turtle conservation. Three years later the Coastal Marine Resource Program was created, currently has four Turtle´s Conservation Projects in the costarican pacific and caribbean coast in Costa Rica.
Due to the importance of the information generated at the sea turtle conservation projects the data needs to be collected that is in a systematic and standardized way to compare the studies of the different sites where ASVO works as well with other sea turtle conservation projects.
Here we describe, step by step our basic field work guidelines. To learn about our research protocol in detail visit our virtual library and check the manual of procedures for data collection at the Turtle Conservation Projects of ASVO.
Before the turtle nesting season starts all our efforts are directed to train the field work staff (biologists and assistants) to achieve an efficient data collection.
The training workshop, How to work with Turtles?, is extended during a week for theoretical and practical work in one of the Turtle´s Conservation Projects.
Construction of the hatchery and beach parceling Hatchery construction
SThis is a key step in the research process because it is used as a strategy to protect the nests. The hatchery is an enclosed beach space, with clean and filtered sand where the nests are placed to protect them from natural predators, poaching, natural disasters, beach instability, among other menaces.
Each hatchery has a different capacity according to the nesting density of beach, the nest density is never less than one nest per square meter.
Beach parceling consists of a division of the beach in sectors an the limits of the parcels are given by wooden poles that have been washed ashore by the tides.
The poles are numbered consecutively starting in the south end of the beach and separated with a distance of 100 meters each. This procedure is performed to determine the nesting spatial distribution on the beach.
Is a walk that is done every day first thing in the morning . These allow us to check or recheck the turtle activities with day light. These activity starts 2 or 3 weeks before the official opening of the nesting season continues with the collection of such information throughout the season.
Thanks to this preliminary activity, it is possible to foresee the general behavior of the nesting season. The census gives us information about nest predation, nest poaching, etc.
The patrols consist of a walk along the beach during the night (8 to 10 hours in total with shifts of 3 to 5 hours it depends in the amount of volunteers available).
Patrols are composed of different groups of volunteers and staff members that have the necessary equipment to tag the turtles, record biometric messurements check the nesting females and work with the nests.
These groups are led by a guide accompanied by an assistant volunteer and volunteers with experience in general.
The patrol groups aim to locate turtles that are in the process of nesting or the nesting site. When they detect the turtle tracks the patrol leader is the responsible to verify if there is an entrance and exit. If the output is not present, he or she has the mission to find the stage of the process in which the female is and make the decisions to work with it.
This process can be done in two ways:
- If the turtle has not started the process of oviposition, a clean plastic bag is placed beneath the cloaca so the eggs are collected directly, avoiding contamination and addition of sand which by friction can damage the eggs.
- When the female has already begun this process, the patrol guide must wait until the turtle finishes the process of oviposition. After the process has ended the leader will search the nest in the sand with a thin wooden stick. Then the eggs are placed in a bag and transferred to the nursery. All the contact with the eggs is done with a great care because of the fragility of them. For all this stage work we use latex gloves and red light to avoid disturbing and stressing the turtles.
When the process of oviposition has ended the patrol leader checks if the if the turtle has the registration marks or not. If the fins are clear of tags the leader places 2 inconel metal tags, one in each front fin. Before that, the area placing the tags, the fins, and the tag are sterilized.
This procedure is done to identify each turtle individually and this procedure helps with the individual turtle stadistics and with the knowledge of the nesting population asossiated to each specific beach.
This activity performed to collect this data is done after the tagging process. It consists of measuring the width and curved carapace length. This process gives us a record of each individual growth over time.
Additional information collected during the patrols and complement the research are:
Reubicación de los huevos
- Beach area (beach parcel)
- Basic information of the weather
- Time and date of event
Once the eggs are collected they are carried to the hatchery or to a security site at the beach, in a time that cannot exceed two hours.
In the relocation site were the eggs will be placed, the original conditions are imitated.
This activity is done with gloves and with the greatest care not to shake the eggs, because at this stage they are particularly vulnerable. Finally the top of the nest is covered with a very fine basket made of mosquito net to prevent entry of predators.
When the first nest gets to the hatchery a 24 for hour guard is needed to protect the eggs from predators to have a complete control of incubation process that is extended from 40 to 60 days depending on the species. The staff in charge of the hatchery will ensure the strict hygiene to prevent pests such as: ants, flies or other organisms that threaten the integrity of the nests.
Hatching and liberation processes
After the incubation time the staff will monitor the nests that are close to the hatching date in order to release the hatclings at the time they emerge from the sand. In this way we prevent the hatchlings from being exhausted or use all their energy reservoirs before going to the sea.
Between 48 and 72 hours after the first emergence of each nest, the staff removes all the biological material in order to count the number of successful eggs and finally know the total of turtles born and the stages of embryological development in which some of the eggs stopped their process.
At the end of the nesting season all of the information collected is processed. The resulting data indicates the health of the population and trends, which function as basic information for conservation guidelines.
All our nesting season final reports are available on the ASVO Library as well as the Manual of Procedure for Turtle Conservation Projects of ASVO.