Mesograzer information

Mesograzers are defined as small invertebrate herbivores less than 2.5 cm in length (i.e., 1 inch), and can include juveniles of some larger species.^[1][2] The feeding behaviour of these small invertebrate herbivores is what classifies them as mesograzers.^[1] They are commonly found abundantly on Microalgae, seagrass beds, giant kelp, and coral reefs globally, since these are their main food sources and habitats.^[3][4][5][6] Their foraging behaviour is grazing on the organism they are living on, where there are typically masses reaching tens of thousands of mesograzers per meter of habitat.^[3] They experience predation from micro-carnivorous fish that help regulate the population of kelp and other common food sources of mesograzers by controlling the population of mesograzers; consequently, grazing is an important process linking aquatic vegetation to higher trophic level.^[7] Mesograzers show important top-down effect on marine communities, depending on the diversity and presence of predators.^[6][3] Mesograzers are typically overlooked in scientific research however their foraging effects have been suggested to have extreme effects on the population of their common food sources.^[3] They both positively and negatively affect macroalgal performance and productivity through grazing on algal (i.e., negative effect), or through removing epiphytes (i.e., positive effects).^[3] Mesograzers typically exist in spaces lacking enemies by inhabiting, therefore consuming, marine vegetation which are defended against more mobile, larger consumers through chemical defenses.^[8]

Mesograzers are quite common in the marine environment, common examples of mesograzers are small Gastropoda, Amphipoda, Isopoda, and small Crustaceans.^[3][9][10]