On the right is an image of a reindeer and in front of it, a pair of penguins. They are standing in a snowy, Christmas scene. On the left, large text on a dark blue background reads "Thermal Imaging Senses Stress in Santa's Little Helpers."

As the night of the 24th December approaches and the Christmas operation ramps up, Santa’s elves have been voicing concerns regarding the welfare of their animal colleagues. Responsible for overseeing the entire Yuletide project on behalf of Father Christmas, elves are particularly anxious about the increased workload leading to increased stress for their reindeer and penguin staff. For this reason, they have been searching for a method of monitoring the health of animal teams without further contributing to their anxiety. Thankfully recent ecological research has revealed that thermal imaging provides an effective, non-contact method of assessing animals for signs of stress.

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Research Reveals Thermal Imaging Can Detect Stress in Animals

Research conducted on King Penguins in the Baie du Marin in Crozet, and published in the Journal of Thermal Biology, revealed that the birds’ heat distribution and body temperature changed when a stress stimulant, such as a predator, was introduced.[1] Agnés Lewden, a penguin specialist at the University Bretagne Occidentale and author of the scientific paper exploring this phenomenon, explains:

“[Penguins’] internal temperature is 38°C thanks to their impermeable plumage, which contributes 80% of the body’s insulation.”

~ Agnés Lewden, Penguin Specialist at the University Bretagne Occidentale

However, when a potential threat or stress stimulant is introduced, for example when a predator passes by, the penguins’ body temperature increases. Moreover, blood flow is redirected to organs and muscles needed to make a quick escape, for example, the brain and eye. As a result, scientists can see, using a thermal camera, that the temperature of the beak decreases, turning a darker blue in the thermal picture; while the temperature around the penguins’ eyes increases, becoming a brighter yellow or white.

Thermal image of a relaxed king penguin. The heat distribution is fairly even all over the penguin's body.
Relaxed penguin. Antoine Stier/French Polar Institute via Camille Lin, ‘Signs of stress visible in the infrared’, Polar Journal.
Thermal image of a stressed king penguin. The heat distribution is concentrated around the penguin's eye, which is white with heat. The beak is a dark blue.
Stressed penguin. Antoine Stier/French Polar Institute via Camille Lin, ‘Signs of stress visible in the infrared’, Polar Journal.

Antoine Stier, a penguin specialist at the CNRS in Strasburg, who is also working on the project clarifies:

“The eye is a good reflection of what’s going on inside.”

~ Antoine Stier, Penguin Specialist at the CNRS, Strasburg

He continues, outlining why the technology is important and detailing his hopes for this emerging method of monitoring warm-blooded animals:

“We could use infrared photo traps to automate the measurements and develop less invasive tools to measure impacts.”

~ Antoine Stier, Penguin Specialist at the CNRS, Strasburg

It is thought thermal cameras will enable biologists to study the phenomenon of habituation to humans, evaluating the effects of heat waves, tourism, and other forms of human activity.

Similarly, an experiment involving eight reindeer (not Santa’s) indicated that thermal imaging effectively assesses stress in animals.[2] Consequently, this technology may be used to monitor animals involved in human activities, or under human care, to guarantee their welfare. For instance, Docent Martin Selmann of the University of Turku, Finland, and co-author of the reindeer study, highlights that:

“By validating infrared thermal imaging as a reliable assessment tool, we can improve the management and treatment of reindeer in tourism settings.”

~ Docent Martin Selmann, University of Turku

Docent Martin Selmann, alongside postdoctoral and lead researcher Océane Liehrmann of the University of Turku, and researchers from the University of Tours, France, conducted their experiment on eight male sledge reindeer employed for tourism in Lapland. These animals were chosen because they were accustomed to human presence but not human touch. Therefore, to test their theory, the scientists had a stranger pet each reindeer for a minute while they recorded the animals' behavioural and thermal responses.

In the background is an out-of-focus reindeer head wearing a brown leather headcollar. In the foreground is a FLIR E6 Thermal Camera through which you can see a thermal image of the reindeer's eye.
Novus Light, Infrared Thermal Imaging Helps Assess Stress in Animals.

When stroked, the reindeer displayed avoidance behaviours, e.g., attempting to dodge human contact and moving away, confirming the activity was stressful. Scientists then used a thermal camera to visualise and measure the temperature around the reindeer’s eyes, choosing this area because it is fur-free. Like the scientists studying penguins, this research team observed a change in temperature around the eyes while the reindeer were being petted. Unlike the team studying penguins, these scientists saw a decrease in temperature, as blood was redirected from the eye to organs and muscles needed for the flight response, e.g., legs. Once the human contact ceased, the temperature around the animals' eyes increased again. Lead researcher Océane Liehrmann said of the findings:

“Our findings demonstrate that infrared thermal imaging can effectively capture the physiological stress responses of reindeer during human interactions. This technology allows us to monitor the emotional states of reindeer without invasive procedures, which is crucial for their welfare.”

~ Océane Liehrmann, Postdoctoral Researcher at the University of Turku

Implications for the Christmas Operation

Previously, monitoring stress levels in animals involved taking blood and saliva samples, which are processes that necessitate human contact, or, in this case, elf contact. As penguins and reindeer may find these interactions stressful, simply gathering the data needed to assess their welfare could jeopardise their welfare and skew the data. Thermal imaging offers a non-contact method of evaluating reindeer and penguin health, thereby removing the human/elf stress stimulus. As a result, carers can accurately assess animals’ stress levels while protecting their immediate well-being.

A colony of king penguins at the front of the colony is a family of four. Two adult penguins and two chicks. One chick is sitting on the left penguin's feet and the other is stood between the two adult penguins, looking at the camera. The penguin on the right is looking at the chick in the middle.
For reindeer are walking through the snow from the left side of the picture towards the right side. These white and brown reindeer are wearing Christmas bridles and harnesses.

This scientific advance should come as a relief to Christmas elves, who have charge of a vast animal team, including:

  • Father Christmas' famous sleigh-pulling reindeer
  • An additional herd of reindeer facilitating inter-workshop logistics and delivering extra present sacks to Santa during his Christmas flight
  • A colony of penguins working across various warehouses

Using thermal cameras, Christmas elves can watch their animal staff for signs of stress, i.e. increases or decreases in eye temperature, ensuring their charges are not overwhelmed by their workload. Where signs of stress are evident, elves can make adjustments to improve the well-being of their animal colleagues, thereby improving morale and, with it, productivity.

Additional Benefits of Thermal Imaging

Christmas elves may also look to uses of thermal imaging in farming and agriculture to guarantee the welfare of reindeer and penguins. For instance, many dairy farms use thermal cameras to spot signs of lameness earlier and without human contact. Spotting lameness early means it can be treated sooner, reducing the animal's discomfort. Furthermore, infrared imaging helps pinpoint the source of lameness, ensuring the cow or reindeer is treated using the correct drugs. Click the link below for more information.

Catch Cattle Lameness with Economical Thermal Cameras

Another study used thermal imaging to assess the insulation of broiler barns and pinpoint sources of draughts. Elves may use this technique to ensure penguin and reindeer living quarters are adequately insulated from the cold. Ensuring animals are kept warm will reduce stress and tiredness, thereby improving their welfare and enabling them to contribute effectively to the Yuletide project. Read more about this study below.

PASS Provides FLIR Thermal Camera for Poultry Farmer’s Barn Ventilation Report

Further Information

For additional advice regarding thermal imaging applications or help choosing an appropriate thermal camera, Christmas elves should contact our Sales team on 01642 931 329 or via our online form.

At PASS Ltd, we stock an array of entry-, mid-, and professional-level thermal cameras by leading manufacturers such as FLIR, Hikmicro, and Seek Thermal. Please browse our extensive range of thermal cameras below.

Browse Thermal Cameras

[1] All information and quotes about the penguin study have been gathered from the following source:

[2] All information and quotes about the reindeer study have been gathered from the following source: