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.