Detecting small and cryptic animals by combining thermography and a wildlife detection dog - PubMed (original) (raw)

Detecting small and cryptic animals by combining thermography and a wildlife detection dog

Denise Karp. Sci Rep. 2020.

Abstract

Small and cryptic species are challenging to detect and study in their natural habitat. Many of these species are of conservation concern, and conservation efforts may be hampered by the lack of basic information on their ecological needs. Brown hare (Lepus europaeus) leverets - one example of such a small, cryptic and endangered animal - are notoriously difficult to detect, and therefore data on wild leverets are virtually non-existent. Novel technologies and methods such as thermal imaging and the use of wildlife detection dogs represent suitable means for the detection of such species by overcoming the problem of camouflage, using heat or scent emission respectively. Our study on brown hare leverets provides information on how to apply these new techniques successfully for the detection of small and cryptic species, thus enabling the collection of data that was previously inaccessible (e.g. behavioural observation, radio tagging). We found that the choice of method should be made according to vegetative structure. While the handheld thermal imaging camera is best used in areas with no or low vegetative cover, the thermal drone can be used up to medium vegetative cover, whereas the detection dog method is best applied where vegetation is very dense and not suitable to be searched using thermography. Being able to search all sort of different vegetation types, our combined approach enables the collection of a balanced and unbiased dataset regarding habitat type and hence selection of study specimen. We hope that the use of these new techniques will encourage research on many cryptic species that formerly have been neglected because they could not be detected using conventional methodologies.

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Conflict of interest statement

The author declares no competing interests.

Figures

Figure 1

Figure 1

(a) Setup for the application of the handheld thermal camera. (b) Suspicious thermal signature in a distance of about 40 meters, corresponding to a leveret in terms of size, shape and brightness. Identification is not possible, thus close inspection is necessary. Small picture: close-up of a thermal signature of a leveret from a distance of 3 meters. Both pictures have been captured with a handheld FLIR Scout TS-32r Pro thermal camera.

Figure 2

Figure 2

(a) Using a thermal drone to search for cryptic wildlife. (b) Thermal picture taken with a FLIR Photon 320 mounted on a microdrones md4–200 quadrocopter nine meters above ground level. The framed spot represents a leveret located within medium - high vegetation density (fallow land).

Figure 3

Figure 3

Wildlife detection dog performing its trained alert upon detection of a leveret: laying down with its head on the ground and the snout pointing into the direction of the target.

Figure 4

Figure 4

Summary of key factors to consider for successful cryptic wildlife detection.

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