Utilization of Body Mass Index as a Health Indicator During Mass-Strandings of Short-Finned Pilot Whales (Globicephala macrorhynchus)

Short-finned pilot whales (Globicephala macrorhynchus) strand or beach along Florida’s coasts regularly (six between the period of 2009 and 2015) and typically in mass numbers. Individual strandings can be caused by, or linked to, changes in environmental conditions, pathogens, stressors, as well as anthropogenic reasons, among others. Historically, it is not understood why an entire pod of these animals would be forced to strand or beach themselves (i.e. mass-strandings), especially when considering that many members of the pod do not exhibit signs of illness or injury. Why do the healthy pod members also strand? Can the healthy animals be isolated and saved? Stranding data for short-finned pilot whales revealed that length and weight have a direct correlation to the medical condition of the animal at the time of stranding and such information could therefore possibly be utilized to increase survivability among the stranded. Length and weight of 24 short-finned pilot whales were used to compute Body Mass Index (BMI) and results show five young whales and multiple females fell below the plotted regression line (r^2=0.8699). In order to decipher this, a case is made herein for utilizing BMI as a health indicator to pinpoint individuals that may be deemed suitable candidates for rehabilitation and/or immediately releasable and disassociated from the sick. BMI calculations support the theory of isolating stranded individuals according to varying health status. A BMI range of 39.0 to 50.0 for adult males and 41.0 to 55.0 for adult female short-finned pilot whales is being suggested. The present study also investigated natural events along both Florida coasts to connect plausible situations in which abrupt changes in oceanographic activity lead to disorientation of short-finned pilot whales and subsequently sends into motion a stranding scenario. A review of oceanic data and literature within the targeted geographic area supports the idea that sudden changes in sea-surface currents can affect, either directly or indirectly, the behavior of short-finned pilot whales and increase the probability of a stranding occurrence, whether individually, or in mass numbers. Cyclonic eddies and areas of coastal upwelling and downwelling can be attributed to causing or leading to the catalyst that triggers a mass-stranding of a particularly social species, such as short-finned pilot whales