TY - JOUR
T1 - Estimating the energetic cost of whale shark tourism
AU - Barry, Christine
AU - Legaspi, Christine
AU - Clarke, Thomas M.
AU - Araujo, Gonzalo
AU - Bradshaw, Corey J.A.
AU - Gleiss, Adrian C.
AU - Meyer, Lauren
AU - Huveneers, Charlie
PY - 2023/8
Y1 - 2023/8
N2 - Wildlife tourism is one of the fastest-growing sectors of the tourism industry, where feeding animals is often applied to increase the probability of up-close encounters. However, directly feeding wildlife can cause behavioural, ecological, and physiological changes in the target species. In Oslob, Philippines, whale shark (Rhincodon typus) tourism involves feeding sharks a total of 150–400 kg sergestid shrimp daily throughout the interaction period from 06:00 to 10:00 from small outrigger boats while tourists observe whale sharks. We deployed tri-axial acceleration loggers on 16 whale sharks and recorded 270 h of acceleration, depth, and water temperature data (0.2–69.7 h). Comparing activity across tourism and non-tourism periods, whale sharks had a two-fold increase in vectorial dynamic body acceleration, and altered tailbeat frequency and amplitude, during tourism operations. Using a bioenergetics model, we show that whale shark metabolic rates increased by 56.7–71.6 % while in the tourism area. A resampling approach found providing ∼220 kg of sergestid shrimp daily would ensure ≥ 0.90 probability of meeting the increased energetic requirements. A global sensitivity analysis revealed that uncertainty in the assumed exponent of the standard metabolic rate was the only input that varied model predictions substantially. Due to unknown consequences of feeding whale sharks, we recommend managers aim to reduce the energy expenditure of whale sharks through operation changes instead of focussing on the quantity of food provided. Our research provides a novel method to contextualise the impacts of tourism beyond behavioural changes.
AB - Wildlife tourism is one of the fastest-growing sectors of the tourism industry, where feeding animals is often applied to increase the probability of up-close encounters. However, directly feeding wildlife can cause behavioural, ecological, and physiological changes in the target species. In Oslob, Philippines, whale shark (Rhincodon typus) tourism involves feeding sharks a total of 150–400 kg sergestid shrimp daily throughout the interaction period from 06:00 to 10:00 from small outrigger boats while tourists observe whale sharks. We deployed tri-axial acceleration loggers on 16 whale sharks and recorded 270 h of acceleration, depth, and water temperature data (0.2–69.7 h). Comparing activity across tourism and non-tourism periods, whale sharks had a two-fold increase in vectorial dynamic body acceleration, and altered tailbeat frequency and amplitude, during tourism operations. Using a bioenergetics model, we show that whale shark metabolic rates increased by 56.7–71.6 % while in the tourism area. A resampling approach found providing ∼220 kg of sergestid shrimp daily would ensure ≥ 0.90 probability of meeting the increased energetic requirements. A global sensitivity analysis revealed that uncertainty in the assumed exponent of the standard metabolic rate was the only input that varied model predictions substantially. Due to unknown consequences of feeding whale sharks, we recommend managers aim to reduce the energy expenditure of whale sharks through operation changes instead of focussing on the quantity of food provided. Our research provides a novel method to contextualise the impacts of tourism beyond behavioural changes.
KW - Accelerometer
KW - Elasmobranch
KW - Energy expenditure
KW - Oslob
KW - Philippines
KW - Provisioning
UR - http://www.scopus.com/inward/record.url?scp=85163847658&partnerID=8YFLogxK
U2 - 10.1016/j.biocon.2023.110164
DO - 10.1016/j.biocon.2023.110164
M3 - Article
AN - SCOPUS:85163847658
SN - 0006-3207
VL - 284
JO - Biological Conservation
JF - Biological Conservation
M1 - 110164
ER -