DOI: 10.5061/dryad.8ct25
title: Data from: Insect herbivory on native and exotic aquatic plants: phosphorus and nitrogen drive insect growth and nutrient release

description: Eutrophication and globalisation facilitate the dominance of exotic plants
 in aquatic ecosystems worldwide. Aquatic omnivores can provide biotic
 resistance to plant invasions, but little is known about whether obligate
 aquatic herbivores can do the same. Herbivores such as insects can
 decimate aquatic vegetation, but may not be able to consume exotic plants
 due to their more or less specialised nature of feeding. We experimentally
 tested the larval feeding of an aquatic insect, the moth Parapoynx
 stratiotata, on eleven submerged plant species, from either native or
 exotic origin. We also tested whether insect herbivory stimulates nutrient
 and organic matter release, thus affecting water quality. Larvae of P.
 stratiotata consumed seven out of eleven plant species, and their growth
 was related to plant nutrient content and stoichiometry. However, larvae
 had no preference for either native or exotic macrophytes, and their plant
 preference was not related to the measured plant traits, but was possibly
 driven by secondary metabolites. Through plant consumption, caterpillars
 induced brownification and phosphate release, and the intensity thereof
 varied among plant species, but not between native and exotic plants. In
 conclusion, P. stratiotata showed strong feeding preferences demonstrating
 that aquatic insects can directly and indirectly alter water quality and
 vegetation composition.
description: Results of caterpillar
 feeding trialsThe results of the
 caterpillar (using Parapoynx stratiotata) feeding trials were conducted in
 the laboratory in the Netherlands and are located in a tab-separated text
 file. Respectively, column headings are: ID [= unique identifier of each
 record], species [= plant species fed upon by caterpillar], fresh biomass
 (g) [= initial plant mass offered to caterpillar], fresh biomass after (g)
 [= remaining plant mass], FWeaten (g) [= fresh plant biomass lost during
 feeding trial], 450nm [= spectrophotometric absorbance at 450 nm after
 experiment], TON [= oxidized nitrogen in water in mg/L], NH4 [= total
 ammonium in water in mg/L], PO4 [= o-phosphate in water in mg/L], NO2 [=
 nitrite in water in mg/L], FW caterpillar end (mg) [= final fresh weight
 of combined caterpillars in milligrams], P% [= plant phosphorus content in
 % of plant dry mass of plant remainder after feeding], C% [= plant carbon
 content in % of plant dry mass of plant remainder after feeding], N% [=
 plant nitrogen content in % of plant dry mass of plant remainder after
 feeding], TPC% [= plant total phenolics content in % of plant dry mass of
 plant remainder after feeding], caterpillar.DM [= caterpillar dry mass
 after feeding], caterpillar.C [= caterpillar carbon content in % of its
 dry mass after feeding] caterpillar.N [= caterpillar nitrogen content in %
 of its dry mass after feeding], caterpillar.P [= caterpillar phosphorus
 content in % of its dry mass after feeding]caterpillar.txtResults of plant CNP stoichiometryResults of chemical analysis to determine the carbon-nitrogen-phosphorus stoichiometry of plant fragments that had not been used in feeding trials. ID [= unique identifier of the record], speciesName [= name of plant species], Replicate [= replicate id within a species], P% [= phosphorus content in % of plant dry mass], C% [= carbon content in % of plant dry mass], N% [= nitrogen content in % of plant dry mass]plantCNP.txt