Enhancing Mangrove Resilience: Assessing Rhizophora sp. Survival in Davao Occidental’s Conservation and Rehabilitation Zones, Philippines

Three distinct sampling locations within Davao Occidental, namely Brgy. Sto. Rosario in Sta. Maria municipality, Sitio Tawang in Brgy. Buhangin, and Sitio Agdao in Brgy. Tubalan in Malita municipality were investigated to evaluate the survival of planted mangroves (Rhizophora sp.). The study revealed a notable discrepancy in survival rates among the sites, with Sitio Agdao exhibiting the highest survival with 97.58%, followed by Sto. Rosario (91.84%), and Sitio Tawang registering 70.46% survival rate. No significant variance was observed between survival rates in Sta. Maria and Malita. Findings indicated diverse causes of mangrove mortality, including strong waves during northeasterly winds impacting Sto. Rosario, flashfloods affecting Sitio Tawang, and the presence of epiphytes (specifically barnacles) in Sitio Agdao. Among the sites, Sitio Tawang exhibited significantly lowest survival rates compared to Sto. Rosario and Sitio Agdao. Substrate analysis revealed clay loam in Sto. Rosario, sandy loam in Sitio Agdao, and sandy clay in Sitio Tawang. The study recommends extending mangrove survival rate monitoring to other conservation and rehabilitation areas, continuing mangrove rehabilitation efforts, and manually removing epiphytes to enhance survival rates.