DOI: 10.5061/dryad.wm37pvn0w
title: Data from: Beyond abiotic decay: Fiddler crabs accelerate plastic fragmentation in pollution hotspots

description: Mangrove forests are recognized as hotspots for plastic sequestration,
 especially in urbanized areas where plastic litter can be up to two orders
 of magnitude more abundant. Fiddler crabs, important ecosystem engineers,
 are thriving in these plastic-rich environments, raising questions about
 how they interact with high plastic loads in the sediments they inhabit
 and feed upon. To explore this, we conducted a field exposure experiment
 in polluted urban mangroves along the southern Caribbean coast of
 Colombia, inhabited by Minuca vocator. Fluorescently labeled polyethylene
 microspheres—small (green, 20–27 μm) and large (red, 75–90 μm)—were
 introduced to mimic the size range of food particles. The experiment
 tracked microsphere uptake over 66 days in crab tissues (hepatopancreas,
 gills, and hindgut) and surrounding sediments. Quality assurance and
 control tests were also conducted to evaluate potential fragmentation
 sources that could affect results. The exposure experiment was approved by
 the Comité de Ética para la Experimentación con Animales -Universidad de
 Antioquia (according to minute 154, issued on 8th August 2023) and the
 collection and mobilization of samples was performed under the “Permiso
 Marco de Recolección de Especímenes de Especies Silvestres de la
 Diversidad Biológica con Fines de Investigación Científica” awarded to
 Universidad de Antioquia by Resolution 0524 (Autoridad Nacional de
 Licencias Ambientales).
description: # Data from: Beyond abiotic decay: Fiddler crabs accelerate plastic
 fragmentation in pollution hotspots Dataset DOI:
 [10.5061/dryad.wm37pvn0w](10.5061/dryad.wm37pvn0w) ## Description of the
 data and file structure Data were collected during an exposure experiment
 of fiddler crabs (*Minuca vocator*) to labelled polyethylene
 microspheres. Two types of fluorescently labelled Polyethylene
 microspheres were used: green microspheres with 20-27 μm diameter and
 0.995 g cm−3 density (Cospheric; product number UVPMS-BG-0.995) and red
 microspheres with 75-90 μm in diameter and 0.995 g cm−3 density
 (Cospheric; product number UVPMS-BR-0.995).  In five 1-m2 plots, 100 ml
 suspensions of green, small microspheres (13,700,000) and red, large
 microspheres (6,900,000) were sprayed directly on the forest floor. These
 plots were distributed within plastic-polluted urban mangrove forests of
 the southern Caribbean coast of Colombia. Moreover, three procedural
 controls were implemented in parallel to the exposure experiment to
 determine whether the fragmentation of microspheres stems from
 physiological processes occurring within the crab's digestive or
 respiratory systems, or if it is an outcome of experimental or handling
 procedures detailed before. * **File 1 (MP_Minuca_vocator)** reports the
 number of whole and fragmented microspheres detected via fluorescence and
 brightfield microscopy in the hepatopancreas, gills, and hindgut of adult
 male and female crabs (five replicates per sampling), along with body size
 and dry mass. Fourteen time points were sampled during the experiment. The
 file also provides microsphere uptake values (number of whole and
 fragmented microspheres per gram of dry body mass). * **File 2
 (MP_sediment)** presents data on the number of whole and fragmented
 microspheres in sediment samples (five replicates), also collected at 14
 time points. * **File 3 (QA_and_CE)** includes quality control data
 assessing microsphere fragmentation in the stock solution, in sediment
 samples, and during tissue processing. ### Files and variables #### File:
 File_3_QA_and_CE.xlsx ##### Variables * Experiment_type: describe the type
 of quality control or control experiment (fragmentation in the
 stock, Fragmentation in the sediment, and procedural control) * Date: the
 day when the experiment was performed, or the sample was taken * Code:
 denote the code for each sample * Sample_type: denote the type of sample
 (stock of microspheres; sediment; crab´s organ) * \# Large
 Microspheres: number of large (75-90 μm diameter) fluorescently labeled
 polyethylene microspheres classified as "who.le."  * \#
 fragments large microspheres: number of large (75-90 μm diameter)
 fluorescently labeled polyethylene microspheres classified as
 "fragments.ted." * % large microspheres fragmented: percentage
 of large (75-90 μm diameter) fluorescently labeled polyethylene
 microspheres classified as "fragmented" in relation to the
 total. * \# small microspheres: number of small (20-27 μm diameter)
 fluorescently labeled polyethylene microspheres classified as
 "whole."  * \# fragments small microspheres:  number of small
 (20-27 μm diameter) fluorescently labeled polyethylene microspheres
 classified as "fragmented." * % small microspheres
 fragmented: percentage of small (20-27 μm diameter) fluorescently labeled
 polyethylene microspheres classified as "fragmented" in relation
 to the total. #### File: File_2_MP_sediment.xlsx ##### Variables *
 Exposure date: the date when the microspheres were sprayed. Sampling date:
 the date when the crab was sampled * Sample_ID: the code for each sediment
 sample is composed of two parts. The first two characters (e.g.,
 "D2") denote the number of days passed after the start of the
 exposure, ranging from D2 to D66. The next character (e.g., S1) denotes
 the sample replicate, ranging from S1 to S5. * Dry mass (g): samples were
 oven-dried (50°C) until constant weight, and the weight was registered. *
 \# whole large MSP: number of large (75-90 μm diameter) fluorescently
 labeled polyethylene microspheres classified as "whole."  * \#
 fragmented large Msp: number of large (75-90 μm diameter) fluorescently
 labeled polyethylene microspheres classified as "fragmented." *
 \# Total largeMSPp: number of whole and fragmented large (75-90 μm
 diameter) fluorescently labeled polyethylene microspheres. * Density large
 Msp (Msp g-1): number of whole and fragmented large (75-90 μm diameter)
 fluorescently labeled polyethylene microspheres per gram of dry sediment.
 * \# whole small MMSP number of small (20-27 μm diameter) fluorescently
 labeled polyethylene microspheres classified as "whole." * \#
 fragmented small Msp: number of small (20-27 μm diameter) fluorescently
 labeled polyethylene microspheres classified as "fragmented." *
 \# Total small Msp: number of whole and fragmented small (20-27 μm
 diameter) fluorescently labeled polyethylene microspheres. * Density small
 Msp (Msp g-1): number of whole and fragmented small (20-27 μm diameter)
 fluorescently labeled polyethylene microspheres per gram of dry sediment.
 #### File: File_1_MP_Minuca_vocator_tissues.xlsx ##### Variables *
 Exposure date: the date when the microspheres were sprayed. * Sampling
 date: the date when the crab was sampled. Note that for each crab, data on
 detected microspheres are given for different organs (hepatopancreas,
 gill, and hindgut). * Sample_ID: code for each sample is composed of three
 parts. The first three characters (e.g., "D-2") denote the
 number of days passed after the start of the exposure, ranging from D-2 to
 D-66. The next character (e.g., S1) denotes the sample replicate, ranging
 from S1 to S5. The last characters (e.g,. R1 denotes the replicate crab,
 which ranges from 1 to 2. * Dry mass (g) was estimated from the
 relationship between body size (carapace width; mm)  and mass (see
 supplementary materials). * Carapace width (mm): measured using a vernier
 calliper. * Sex (male or female) is determined by visual inspection of
 sexual characters (see methods). When ovigerous females were detected,
 they were reported as "Female(Ov)." * Organ_type: three types of
 organs were inspected: hepatopancreas, gill,  ls, and hindgut * \#
 Large_whole_Mps\_ Mps: number of large (75-90 μm diameter) fluorescently
 labeled polyethylene microspheres classified as "whole." * \#
 Large_fragmented\_ Mps: number of large (75-90 μm diameter) fluorescently
 labeled polyethylene microspheres classified as "fragmented." *
 \# Total_large_Mps: number of whole and fragmented large (75-90 μm
 diameter) fluorescently labeled polyethylene microspheres. *
 Uptake_large_Mps (Mps g-1): number of whole and fragmented large (75-90 μm
 diameter) fluorescently labeled polyethylene microspheres per gram of dry
 mass. * \# Small_whole_Mps\_ Mps: number of small (20-27 μm diameter)
 fluorescently labeled polyethylene microspheres classified as
 "whole." * \# Small_fragmented\_ Mps: number of small (20-27 μm
 diameter) fluorescently labeled polyethylene microspheres classified as
 "fragmented." * \# Total_small_Mps: number of whole and
 fragmented small (20-27 μm diameter) fluorescently labeled polyethylene
 microspheres. * Uptake_small_Mps (Mps g-1): number of whole and fragmented
 small (20-27 μm diameter) fluorescently labeled polyethylene microspheres
 per gram of dry mass. Note: "N/A" was reported for cells
 corresponding to "hindgut" when hindgut contents were empty ##
 Code/software Data can be read with Microsoft Excel