Photosymbiont and N_P data from Curacao and Barbados

Nutrient pollution has been a major contributor to coral decline throughout the Caribbean. Coral physiological responses to excess nutrients vary with nutrient forms (e.g., nitrate or ammonia), concentrations, and nitrogen-to-phosphate (N:P) ratios. However, how these responses differ across nutrient contexts remains understudied. We show that Orbicella annularis photosymbiont densities respond differently to excess nitrogen in phosphorus-limited versus nitrogen-limited environments. Along Curaçao's leeward reef, excess nitrogen significantly decreased (P < 0.05) photosymbiont density under phosphorus-limited conditions (N:P > 16) with low phosphorus (mean = 0.07 µM ± 0.06). In contrast, data from Barbados indicate a significant increase (P < 0.01) in photosymbiont density under nitrogen-limited conditions (N:P < 16). These findings highlight how nutrient contexts shape coral responses to nitrogen inputs, emphasizing the need to consider nutrient dynamics in coral conservati..., , , # Photosymbiont and N\_P data from Curacao and Barbados

[https://doi.org/10.5061/dryad.9s4mw6msv](https://doi.org/10.5061/dryad.9s4mw6msv)

## Description of the data and file structure

#### File: Photosymbiont\_Curacao\_Barbados\_DataJune2025.xlsx

This dataset compiles environmental and biological data relevant to photosymbiotic corals from Curacao and Barbados. The dataset includes time series of nutrient concentrations, calculated nutrient ratios (e.g., N:P), and symbiont densities for coral samples from both locations, along with additional metadata.

The dataset is intended to support analyses exploring the relationship between nutrient regimes and coral photosymbiosis across temporal and spatial gradients.

| Column Name | Description |
| :----------------...,