Outdoor seating near lakes, rivers, or ponds has become increasingly popular in urban and recreational areas. While it enhances human enjoyment, its ecological impact—particularly on local daphnia populations—is often overlooked. Daphnia, small freshwater crustaceans, play a critical role in aquatic ecosystems by filtering algae and serving as a food source for fish.

The presence of outdoor seating can indirectly harm daphnia in several ways. Increased human activity often leads to higher nutrient runoff (e.g., from food waste or sunscreen), which may cause algal blooms. While daphnia consume algae, excessive blooms can deplete oxygen levels, creating dead zones. Additionally, chemical pollutants from nearby seating areas, such as detergents or pesticides, can disrupt daphnia reproduction and survival.

Shade from seating structures may also alter water temperature and light penetration, affecting phytoplankton growth—a primary food source for daphnia. Conversely, well-designed seating with buffer zones and natural vegetation can mitigate these effects by filtering runoff before it reaches the water.

To protect daphnia and aquatic biodiversity, urban planners should consider eco-friendly seating materials, proper waste management, and maintaining natural shorelines. Balancing human recreation with ecological health ensures thriving daphnia populations and resilient water ecosystems.