Impact of marine hitchhiker load on host energy intake

Determining the energetic and fitness trade-offs associated with symbiotic relationships (mutualism, commensalism, or parasitism) can reveal the implications of symbiosis for species and ecosystem health. To identify hitchhiker impact on sea turtles, this study reviewed global literature and examined the association between remoras (Echeneis naucrates) and green turtles (Chelonia mydas) at a high-density foraging site in the Red Sea using SCUBA and video (n = 71 observations) in October 2023. Previous evidence of remora-sea turtle association is limited to qualitative observations from the Atlantic and Pacific Oceans. The results show that depth significantly impacted the number of remoras per turtle (p < 0.05). Turtle grazing rate was affected by remora load (p < 0.05), decreasing by ~30% across the load range from a mean of 22.8 bites min-1 (0 remoras) to 15.6 bites min-1 (3 remoras). There was little evidence of benefit to turtles, with only one observation of a remora cleaning..., , # Impact of marine hitchhiker load on host energy intake

Dataset DOI: [10.5061/dryad.ns1rn8q5t](https://doi.org/10.5061/dryad.ns1rn8q5t)

## Description of the data and file structure

This repository contains data used in Kale et al. (2025) to examine the costs and benefits associated with remoras (*Echeneis naucrates*) hitchhiking on green turtles (*Chelonia mydas*) in the Egyptian Red Sea. The file includes data collected during SCUBA surveys.

**Study overview**

To improve our understanding of the remora-sea turtle relationship, we explored the following relationships:

1\)    Remora presence/absence *vs* turtle size

2\)   Mean number of remoras per turtle (hereafter remora load) *vs* depth

3\)   Mean grazing rate per turtle *vs* turtle size, mean remora load per individual, and depth

### Files and variables

#### File: Data_Marine_hitchhiker_impact.csv

**Description:** This file contains data collected during SCUBA surveys to examine the remora-green turtle relationship using...,