Kelp habitat suitability final report

Kelp forests depended on the presence of rocky substrate, cold waters, and water motion from tides and waves. Other kelp suitability factors included light and nutrient availability, the absence of predatory urchins, and the presence of competitive or invasive algae. Key parameters and thresholds for the kelp model were determined in consultation with subject experts and included recent satellite-derived information collated under the University of Victoria Spectral Lab’s Kelp Resiliency Project/Kelp Alliance led by Dr. Maycira Costa. This PSF-supported program assessed key ecological and environmental parameters associated with kelp persistence, guiding the prioritization and mapping of areas of the Salish Sea where kelp were most likely to recover following marine heat waves and the impacts of climate change. Parameters were modeled throughout the focus estuaries and nearshore areas of the northern Salish Sea and were classified as either unsuitable, within acceptable tolerance limits but not optimal, or within optimal tolerance limits. A multiplicative model was applied in which areas with higher scores represented areas of higher suitability, areas with lower scores represented areas of lower suitability, and a score of zero represented unsuitable habitat. Where data for key parameters were missing and/or of reduced quality, this project provided recommendations for future data collection, which could later be incorporated back into the habitat suitability models.