# Infrared Thermography of the Blowhole as a Potential Diagnostic Tool for Health Assessment in Killer Whales (Orcinus orca)

## TL;DR

Infrared thermography of the blowhole can detect health issues in killer whales by identifying elevated temperatures linked to inflammation.

## Contribution

This study demonstrates infrared thermography as a non-invasive method to detect pyrexia in killer whales.

## Key findings

- Blowhole infrared thermography detected elevated temperatures in two killer whales with inflammation.
- Elevated blowhole temperatures correlated with rectal temperatures and systemic inflammatory markers.
- Thermography returned to baseline after veterinary treatment, confirming its diagnostic potential.

## Abstract

Non-invasive techniques, such as infrared thermography, are ideal diagnostic tools for evaluation of the health status of marine megafauna such as killer whales (Orcinus orca). Infrared thermography of the blowhole was implemented in the diagnostic work-up of two male killer whales (also known as ‘orcas’) under managed care, and accurately detected changes in blowhole mucosa emissivity consistent with pyrexia in both cases. Infrared thermography of the blowhole is a potentially useful addition for the health assessment of killer whales as a screening tool to identify pyrexic animals within a group. The aim of this case report is to describe the clinical presentation and diagnostic findings in two killer whales with signs consistent with inflammation and pyrexia, most notably that an increase in blowhole temperature obtained by infrared thermography aligned with increased rectal temperature.

Killer whales (Orcinus orca) are experiencing increasing environmental pressures, with some ecotypes being identified as endangered, and the development and validation of non-invasive health assessment tools is critical for assessing the well-being of individuals within these endangered populations. Infrared thermography of the blowhole is a non-contact method of temperature measurement that was recently investigated in killer whales in managed care. Two male killer whales presenting with clinical signs at separate institutions had veterinary clinical health assessments performed, which included infrared thermography of the blowhole as well as concurrent rectal temperature measurement. The current case report is aimed at describing the clinical use of infrared thermography of the blowhole as a method to detect elevated body temperature in two killer whales. Both animals exhibited blowhole temperatures above the previously reported values (36.4 °C and 37.6 °C; the mean in healthy whales is reported to be 34.21 ± 1.47 °C) with concurrently elevated rectal temperatures, as well as clinicopathologic findings consistent with a systemic inflammatory response (e.g., neutrophilia, increased fibrinogen and erythrocyte sedimentation rate, hypoferritinemia). Following veterinary intervention, both animals’ blowhole and rectal temperatures returned to baseline. Infrared thermography of the blowhole represents a promising tool for the identification of pyrexic animals and with further investigation may be considered as part of conservation health assessments for threatened free-ranging populations.