Moving towards sustainable whale shark-human interactions: A case study in Bahía de La Paz, Baja California Sur, Mexico

Abstract

Whale shark tourism has experienced a significant increase in demand in recent decades, which may stress these animals or alter their behavior. Therefore, assessing the tourism carrying capacity (TCC) for whale-shark interactions is crucial for sustainable management. Despite Bahía de La Paz being established as a whale shark refuge in 2018 and improvements in management strategies for human-whale shark interactions due to increased oversight of tourism providers, 50–60 % of whale sharks are still injured yearly. This research assesses the TCC for swim-with-whale shark activities at the aggregation site in Bahía de La Paz to incorporate it into a decision-support system for tourism management. We developed the numerical formulation of the TCC following the precautionary principle based on the management factors necessary to estimate a carrying capacity that aligns with current whale shark regulations in Mexico, derived from monitoring data collected between 2005 and 2022. We compared the TCC assessments conducted for two scenarios: a low-regulated period (2015–2016 season) and a high-regulated period (2018–2022 season). The effective carrying capacity (ECC) post-regulation allows more tourism boats per turn compared to the pre-regulation period, primarily due to increased observed whale sharks. In addition, we present a dynamic TCC assessment that adjusts the number of tourist boats based on the observed whale shark population in the area. We hope the government implements this model into the management plan of the species to reduce pressure on whale sharks and lessen the impact on the species.