GEB2020_data.xlsx

This data set corresponds to the study published in Global Ecology and Biogeography entitled: “Latitudinal variation in plant defense against herbivory in a marine foundation species does not follow a linear pattern: the importance of resource availability” We conducted experiments simulating macroherbivore (e.g., bird, fish) damage in Zostera marina at 10 sites across the Eastern Pacific coast (Canada-Mexico) and Quebec and analyzed several seagrass traits related to resistance and tolerance strategies against herbivory. In addition, we examined the effects of potential seagrass changes in defense strategies by performing a series of feeding experiments with mesoherbivores in a subset of sites. We found that eelgrass resistance defenses did not follow a linear latitudinal pattern but rather followed a bell-shaped curve which correlated with bottom-up control. In sites with higher nutrient availability, plants allocated resources to tolerance strategies and had lower resistance traits. Furthermore, seagrasses did not respond linearly to increased herbivory pressure; while they tolerated moderate levels of herbivory, they underwent a significant reduction in tolerance and resistance under high herbivory levels, which also made them more susceptible to consumers in feeding experiments. Our results highlight the importance that nutrient availability has in shaping latitudinal patterns of plant defense against herbivory and show how these defenses may not respond linearly to increased herbivory pressure in seagrasses.