DOI: 10.5061/dryad.931zcrjt0
title: Macroinvertebrate habitat use and the cascading effects of a native and non-native species

description: Introductions of novel ecosystem engineers to our estuaries and coasts are
 often associated with strong impacts on the environment, with some
 altering community and behavioral interactions, especially if they are
 part of a cascading interaction. In some US Mid-Atlantic soft-sediment
 mudflats adjacent to salt marshes, the native predatory
 polychaete Diopatra cuprea preferentially decorates its mucus
 tube with the invasive red alga Gracilaria vermiculophylla. This
 may be due to a facilitation cascade between these species, possibly
 increasing the availability of invertebrate prey for D. cuprea. To
 determine the effects of facilitation of G. vermiculophylla by D. cuprea
 on invertebrates associated with algae, we compared communities inhabiting
 G. vermiculophylla and Ulva spp. decorations using a field manipulation
 experiment. Additionally, we tested invertebrate habitat-use in the
 laboratory with a microcosm choice experiment. In the field, the
 interaction between site, algal species, and worm presence drove
 macroinvertebrate species richness and abundance, with a pattern of higher
 species richness on D. cuprea tubes with G. vermiculophylla decorations,
 and a pattern of higher abundance on Ulva spp. decorations when D. cuprea
 was. In the laboratory, the abundant amphipod species Gammarus mucronatus
 associated with G. vermiculophylla over Ulva spp. regardless of D. cuprea
 presence. Our study suggests that algal species is only one of multiple
 factors which structure macroinvertebrate community composition, while
 laboratory trials suggested that specific invertebrates may show
 preference for certain algae. This work highlights the complex
 interactions between native and non-native species and their associated
 communities, which may incur facilitation cascades as a result of novel or
 changing species interactions.
description: # Macroinvertebrate habitat use and the cascading effects of a native and
 non-native species These data were used to analyze aquatic invertebrate
 habitat use, focusing on the Diopatra cuprea and Gracilaria
 vermiculophylla system at three different sites on the Eastern Shore of
 Virginia. We analyzed biomass loss of algae in the field, abundance,
 richness, and community patterns of invertebrates on algae anchored to
 either D. cuprea tube caps or worm mimics, and habitats which specific
 aquatic invertebrates used when given multiple options. We found that the
 common Ulva spp. showed the highest biomass loss, we saw an interaction
 between site, algal species, and mimics in the field, and we observed a
 preference for one of the aquatic invertebrates, Gammarus mucronatus to
 use the G. vermiculophylla habitat over Ulva spp. regardless of worm
 presence. Contact Alexander Mott
 ([[amott3@gmu.edu](mailto:amott3@gmu.edu)]) with any questions. This
 manuscript is accepted for publication (11/29/24) Mott, A.W., A.M.H.
 Blakeslee, S.A. Krueger-Hadfield, A.E. Fowler, Is macroinvertebrate
 habitat use driven by the cascading effects of a native polychaete and a
 non-native alga? Ecosphere (accepted). ECS24-0109.R1 R Script
 (file:Mott_Ecosphere_2025_Codes.R) can be found with the rest of these
 data files. Data files: \##Algae_Weights_Figure.csv This file contains
 weights of algae for the biomass retention experiment, and was used to run
 the GLM for that experiment, and to generate Figure 2. All data were
 collected by authors. | variables | units | description | |
 :--------------- | :---------- |
 :------------------------------------------------------------------------------------------------------------------------------- | | Site | categorical | Name of the location | | Algae | categorical | Code for the algae being tested, GV=Gracilaria vermiculophylla, GVUL=Gracilaria vermiuclophylla and Ulva spp., UL=Ulva spp. only | | Sample | number | Identifier for replicate at the site | | Wet Weight | grams | Biomass of algae after 2 weeks prior to drying | | Actual Weight | grams | Dry biomass of algae after 2 weeks | | Biomass Retained | % | Percentage of wet biomass remaining after 2 weeks (compared to 10g wet weight) | \##RichnessandAbundanceOutlierDeleted.csv \##RichnessandABundanceGraphed.csv The file RichnessandAbundanceOutlierDeleted.csv was used to run the GLM for species richness, and to generate Figure 3. The file RichnessandAbundanceGraphed.csv was used to run the GLM for species abundance, and to generate Figure S1, Figure S2, and Figure S3. Both "RichnessandAbundanceGraphed.csv" and "RichnessandAbundanceOutlierDeleted.csv" have the same format with the same variables. The latter excludes a few samples where species richness was calculated at &gt;50/gram for analysis purposes. All data were collected by the authors. | variables | units | description | | :--------------------- | :-------------- | :------------------------------------------------------------------------------- | | Sample | number | Identifier for replicate at the site | | Site | categorical | Name of the location | | Algae | categorical | Algae anchored to the sample tube cap | | Type | categorical | Identifier for either mimic-control or live worm | | Abundance | number | Total count of all organisms found on the sample | | Weight | grams | Dry biomass of decoration found on the sample tube cap | | Org/Gram | number per gram | Measurement of how many organisms are found in a single gram of algae decoration | | Rounded | number per gram | Measurement of organisms per gram rounded up to the nearest whole number | | G. mucronatus | number | Number of Gammarus mucronatus individuals found in a sample. | | Amphithae valida | number | Number of Amphithae valida individuals found in a sample | | Amphipod A | number | Number of unidentified "Amphipod A" individuals found in a sample | | Alitta succinea | number | Number of Alitta succinea individuals found in a sample | | Caprellidae B | number | Number of unidentified "Caprellidae B" individuals found in a sample | | Spionidae A | number | Number of unidentified "Spionidae A" individuals found in a sample | | Xanthidae | number | Number of Xanthidae individuals found in a sample | | Corophium A | number | Number of unidentified "Corophium A" individuals found in a sample | | Cyathura polita | number | Number of Cyathura polita found in a sample | | Palacmontes purgio | number | Number of Palacmontes purgio individuals found in a sample | | Snail A | number | Number of unidentified "Snail A" individuals found in a sample | | Snail B | number | Number of unidentified "Snail B" individuals found in a sample | | Bittiotum alternatum | number | Number of Bittiotum alternatum individuals found in a sample | | Erichsonella attenuata | number | Number of Erichsonella attenuata individuals found in a sample | | Hydrobia spp. | number | Number of Hydrobia spp. individuals found in a sample | | Boonea impressa | number | Number of Boonea impressa individuals found in a sample | | Ilyanassa obsoleta | number | Number of Ilyanassa obsoleta individuals found in a sample | | Snail D | number | Number of unidentified "Snail D" individuals found in a sample | | Edotea trilobu | number | Number of Edotea trilobu individuals found in a sample | | Callinectes sapidus | number | Number of Callinectes sapidus individuals found in a sample | | Polychaete A | number | Number of unidentified "Polychaete A" individuals found in a sample | | Crab Megalope | number | Number of unidentified "Crab Megalope" individuals found in a sample | | Tanadazea | number | Number of Tanadazea individuals found in a sample | | Richness | number | The number of unique species found in a sample | | Rich.Weight | number per gram | Number of unique species found in one gram of algae decoration | | Rounded Rich.Weight | number per gram | Measurement of species richness per gram rounded up to the nearest whole number | | Crab Megalope | number | Number of unidentified "Crab Megalope" individuals found in a sample | | Tanadazea | number | Number of Tanadazea individuals found in a sample | | Groups | category | Identifier used for formatting Figure 3 | \##MostAbundantSpecies.csv This files contains counts of the four most abundant species across all three sites measured, and is used to create Figure 4. All data were collected by the authors. | variables | units | description | | :-------- | :---------- | :---------------------------------------------- | | Site | categorical | Name of the location | | Species | categorical | Name of one of the common species being counted | | Count | number | Count of the organisms found at the given site | \##AlFarmAllDataWeightAdjusted.csv This file is used to run non-metric Multidimensional Scaling analyses on the samples collected, which was subsequently used to generate Figure 5. All data were collected by the authors. | variables | units | description | | :--------------------- | :---------- | :------------------------------------------------------------------- | | Site | categorical | Name of the location | | Type | categorical | Identifier for either mimic-control or live worm | | Algae | categorical | Algae anchored to the sample tube cap | | Weight | grams | Dry biomass of decoration found on the sample tube cap | | G. mucronatus | number | Number of Gammarus mucronatus individuals found in a sample. | | Amphithae valida | number | Number of Amphithae valida individuals found in a sample | | Amphipod A | number | Number of unidentified "Amphipod A" individuals found in a sample | | Alitta succinea | number | Number of Alitta succinea individuals found in a sample | | Caprellidae B | number | Number of unidentified "Caprellidae B" individuals found in a sample | | Spionidae A | number | Number of unidentified "Spionidae A" individuals found in a sample | | Xanthidae | number | Number of Xanthidae individuals found in a sample | | Corophium A | number | Number of unidentified "Corophium A" individuals found in a sample | | Cyathura polita | number | Number of Cyathura polita found in a sample | | Palacmontes purgio | number | Number of Palacmontes purgio individuals found in a sample | | Snail A | number | Number of unidentified "Snail A" individuals found in a sample | | Snail B | number | Number of unidentified "Snail B" individuals found in a sample | | Bittiotum alternatum | number | Number of Bittiotum alternatum individuals found in a sample | | Erichsonella attenuata | number | Number of Erichsonella attenuata individuals found in a sample | | Hydrobia spp. | number | Number of Hydrobia spp. individuals found in a sample | | Boonea impressa | number | Number of Boonea impressa individuals found in a sample | | Ilyanassa obsoleta | number | Number of Ilyanassa obsoleta individuals found in a sample | | Snail D | number | Number of unidentified "Snail D" individuals found in a sample | | Edotea trilobu | number | Number of Edotea trilobu individuals found in a sample | | Callinectes sapidus | number | Number of Callinectes sapidus individuals found in a sample | | Polychaete A | number | Number of unidentified "Polychaete A" individuals found in a sample | | Crab Megalope | number | Number of unidentified "Crab Megalope" individuals found in a sample | | Tanadazea | number | Number of Tanadazea individuals found in a sample | \##AbundanceWeightSimperEnv.csv This file contains the environmental data for each sample. This file, along with "AbundanceWeightSimper.csv" are used for the SIMPER analyses. All data were collected by the authors. | variables | units | description | | :-------- | :---------- | :----------------------------------------------------- | | Site | categorical | Name of the location | | Type | categorical | Identifier for either mimic-control or live worm | | Algae | categorical | Algae anchored to the sample tube cap | | Weight | grams | Dry biomass of decoration found on the sample tube cap | \##AbundanceWeightSimper.csv This file contains the counts of all species found in each sample. This file, along with "AbundanceWeightSimperENV.csv" are used for the SIMPER analyses. All data were collected by the authors. | variables | units | description | | :--------------------- | :----- | :------------------------------------------------------------------- | | G. mucronatus | number | Number of Gammarus mucronatus individuals found in a sample. | | Amphithae valida | number | Number of Amphithae valida individuals found in a sample | | Amphipod A | number | Number of unidentified "Amphipod A" individuals found in a sample | | Alitta succinea | number | Number of Alitta succinea individuals found in a sample | | Caprellidae B | number | Number of unidentified "Caprellidae B" individuals found in a sample | | Spionidae A | number | Number of unidentified "Spionidae A" individuals found in a sample | | Xanthidae | number | Number of Xanthidae individuals found in a sample | | Corophium A | number | Number of unidentified "Corophium A" individuals found in a sample | | Cyathura polita | number | Number of Cyathura polita found in a sample | | Palacmontes purgio | number | Number of Palacmontes purgio individuals found in a sample | | Snail A | number | Number of unidentified "Snail A" individuals found in a sample | | Snail B | number | Number of unidentified "Snail B" individuals found in a sample | | Bittiotum alternatum | number | Number of Bittiotum alternatum individuals found in a sample | | Erichsonella attenuata | number | Number of Erichsonella attenuata individuals found in a sample | | Hydrobia spp. | number | Number of Hydrobia spp. individuals found in a sample | | Boonea impressa | number | Number of Boonea impressa individuals found in a sample | | Ilyanassa obsoleta | number | Number of Ilyanassa obsoleta individuals found in a sample | | Snail D | number | Number of unidentified "Snail D" individuals found in a sample | | Edotea trilobu | number | Number of Edotea trilobu individuals found in a sample | | Callinectes sapidus | number | Number of Callinectes sapidus individuals found in a sample | | Polychaete A | number | Number of unidentified "Polychaete A" individuals found in a sample | | Crab Megalope | number | Number of unidentified "Crab Megalope" individuals found in a sample | | Tanadazea | number | Number of Tanadazea individuals found in a sample | \##OysterWormUlRare.csv \##OysterWormGVRare.csv \##OysterControlUlRare.csv \##OysterControlMixRare.csv \##OysterControlGVRare.csv \##QuinbyWormUlRare.csv \##QuinbyWormMixRare.csv \##QuinbyWormGVRare.csv \##QuinbyControlUlRare.csv \##QuinbyControlMixRare.csv \##QuinbyControlGVRare.csv \##MachoWormMixRare.csv \##MachoWormGVRare.csv \##MachoControlUlRare.csv \##MachoControlMixRare.csv \##MachoControlGVRare.csv These files contain the s(est) data used to produce the rarefaction curves. Each file is named in such a way where the first word represents the site: either Macho (Machipongo), Oyster, or Quinby, the second word represents if the data comes from either Control (Worm Mimic Control) or Worm (Live Worm), and the third word represents the anchored algae: GV (Gracilaria vermiculophylla), Ul (Ulva spp.) or Mix (Mixture of both Gracilaria vermiculophylla and Ulva spp.). Estimate data was calculated using EstimateS software. All data were collected by authors. | variables | units | description | | :------------------------ | :------ | :-------------------------------------------------------------------------------------------- | | Samples | number | Computated number of samples | | Individual | number | Number of individual organisms calculated | | S(est) | number | The estimated number of species expected to be found in a sample. | | S(est) 95% CI Lower Bound | percent | The lower 95% confidence interval of the estimated number of species to be found in a sample. | | S(est) 95% CI Upper Bound | percent | The upper 95% confidence interval of the estimated number of species to be found in a sample. |