Mangrove zone nitrogen levels spike, alarming Costa Mar monitors

The Costa Mar Reef Monitoring Network reported elevated nitrogen readings at three stations along the central mangrove belt on Tuesday, with concentrations at the Bahía Verde station climbing to 8.2 milligrams per litre—nearly double the five-year average. The spike follows weeks of above-normal rainfall and has prompted the Marine Ministry in Puerto Azul to expand water-quality sampling across the region's northern inlets.

Nitrogen pollution accelerates algal blooms that smother coral and seagrass beds, a familiar threat to Costa Mar's ecosystem. The monitoring network has tracked smaller fluctuations for years, but the scale and speed of this reading have drawn the attention of dive operators and conservation groups, who see it as a sign that upstream pressures on the coastal system are intensifying.

The Marine Ministry said it will convene the Coastal Stewardship Committee next week to review the data and consider whether new protocols are needed for agricultural discharge and stormwater management. Officials have not yet identified the source of the runoff, but preliminary analysis suggests contributions from multiple inland sites rather than a single contamination event.