Guidelines for the long term Monitoring programmes for marine turtles nesting beaches and standardized monitoring methods for nesting beaches, feeding and wintering areas.

Abstract

This Guideline describes and suggests improvement on the methodology for the long-term standardized collection and assimilation of data on adult and juvenile loggerhead (Caretta caretta) and green (Chelonia mydas) sea turtles at nesting, foraging and wintering areas throughout the Mediterranean. In particular, it suggests (i) standardised monitoring techniques for establishing the current distribution of nesting, wintering and feeding areas in parallel to detecting shifts in distribution over time and (ii) standardised monitoring techniques for establishing the population size of selected nesting, wintering and feeding areas, along with proposed selection criteria to assimilate a representative cross-section of sites nationally based on the provisions of the UNEP(DEPI)/MED IG.22/Inf.7, the IMAP and the Common Indicators factsheets. The combined use of a variety of assessment techniques is suggested to facilitate demographic analyses, which should be covered in the ‘Standardization of methodologies to estimate demographic parameters for population dynamics analysis, such as population modelling’. Due to the different financial, personnel, equipment and National Security status of the countries bordering the Mediterranean, the document has been structured to suggest (1) essential baseline information for collection throughout all countries and (2) additional information for collection at a network of sites with different characteristics to enhance demographic models and the assessment of key pressures to sea turtles. It is essential to obtain a broad understanding of the current distribution and numbers of sea turtles across all sites to record future shifts in response to changes in anthropogenic pressure, including climate change. In order to ensure that data are standardised with the aim of facilitating the sharing and analysis of information at the Mediterranean scale, the agreement of the collaborative parties is required along with the willingness to participate from the main contributors (research organisations, universities, fishers, individuals etc.). A central body should be assigned to liaise with participants/contributors, ensure that the information are inserted in the appropriate database with relevant linkages among all databases (ultimately, genetics data should link all other data inputs). Depending on the type and detail of information, layers could be generated on a GIS database, building on Mediterranean wide surveys conducted every 5-years (supporting the suggestion of the Demography Working Group 2015). This approach would allow gaps in monitoring (location and level of information provided) to be identified at the Mediterranean scale, and addressed at regular intervals. Furthermore, by assimilating all data in a central database, the access and use can be standardised, allowing nesting areas to be connected with foraging and wintering areas, which generally occur in different countries. Ultimately, as bias will always exist, this suggested approach will facilitate variation in effort across all involved nations, maximising our understanding and ability to improve the protection of sea turtles at the Mediterranean scale.