Latitudinal variation in seagrass herbivory: global patterns and explanatory mechanisms

Aim: The aim was to quantify latitudinal patterns in seagrass–herbivore interactions in the context of a warming climate.

Location: We carried out a global meta‐analysis combined with a field experiment across 1,700 km and 12° of latitude in Western Australia.

Time period: 1984–2014.

Major taxa studied: Seagrasses.

Methods: We first synthesized the global literature on herbivore exclusion experiments in seagrasses to test whether differences in herbivore impacts are related to latitude and sea surface temperature. We then quantified leaf production and consumption rates in the field at nine meadows of the seagrass Amphibolis antarctica across 1,700 km, from tropical to temperate latitudes. Seagrass biomass and nutritional traits (nitrogen, C:N, phenolics) were also measured.

Results: Our meta‐analysis showed that herbivores had a similar net impact on seagrasses across 37° of absolute latitude, and there was little variation in herbivore exclusion effects at different tem...