Beyond abiotic decay: Fiddler crabs accelerate plastic fragmentation in pollution hotspots

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..., , # 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 ex...,