115 frequentation is stable at the scale of this study, we extrapolated the mean values of each of the three indexes to the 2017-18 to 2019-20 nesting seasons. We also generated an ordinal variable representative of the protective status in force at the time of the survey effort (‘protection_index”), with 0= ‘no access restriction’; 1= ‘temporal access restriction’ and 2= ‘permanent access restriction’, based on the South Province activity report data. This set of eleven variables will hereafter be referred to as the ‘islet’ variable type. 3.3.2 Habitat characterization Nesting islets geomorphology surveys were carried out concomitantly with nest activities surveys over the 2019-20, 2021-22 and 2022-23 nesting seasons. They consisted in the inventory of a set of habitat characteristics assumed to drive sea turtles nesting site selection, following a methodology developed by Garcin et al. (2022). Each islet was divided into sectors presenting homogeneous habitat characteristics. Several habitat variables were then measured and calculated per sector: the length of the coastline (‘sector_length’), the exposition with respect to a reference point centered on the orientation of the predominant trade wind regimes, i.e. 135°, (high values will be associated with high exposition to winds) (‘sector_exposition’), and the width of the reef-flat fringing the sector (‘reef_flat_wideness’), by applying an orthogonal projection from the central position of the sector to the external limit of the facing fringing reef. Geomorphological variables were also estimated per sector: height of the erosion scarp (‘erosion_scarp’), type of beach rock (‘beach_rock’), stumps and/or wooden debris concentration (‘woody_debris’), and sediment granulometry (‘granulometry’). They were afterwards classified into five categories ranging from 2= ‘very favorable’ to -2= ‘very unfavorable’, based on the methodology developed by Garcin et al. (2022) (Table 15 SI Appendix). Finally, a synthetic overall sector score of nesting habitat suitability was estimated (‘sector_score’), also ranging the same -2 to 2 scale, and based on the values of all the latter parameters (Garcin et al. 2022). This set of seven variables will hereafter be referred to as the ‘habitat’ variable type. In order to test the influence of the ‘habitat’ variables upon the distribution of nesting activities, a predicted seasonal number of nests was inferred for each predefined sector (‘nest_sector_median’). This nest count has only been generated over seasons in which the considered islet has effectively been monitored, as it is based on the percentage of observed number of nests in each i sector over the total observed number of nests in the y islet, and the predicted seasonal number of nests on the y islet:
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