Fieldwork and data collection in remote field studies and variable climate conditions often entails challenges that require creative minds seeking for solutions to be as efficient as possible. We carry out research in a large study area of approximately 40,000 km² in central Namibia and several other study areas located across entire Namibia. Most of our fieldwork entails the capture, immobilization and sampling of free-ranging cheetahs as well as camera trapping and data retrieval from GPS collars. These tasks often involve long journeys and considerable driving. Using the innovative and trouble-shooting skills of our team as well as our technical knowledge, we developed several state-of-the-art approaches to efficiently use the resources available. An important aspect of all our developments is that they are absolutely safe for the animals and in full accordance with animal welfare standards. Some of our inventions were submitted to the patent office where they are currently pending.

Electronic and remotely monitored box-traps

For ethical and welfare reasons, the capture of wildlife should be selective and efficient, and minimize the possibility of injuries and stress levels of the animals. We developed an automatic solar powered box-trap controlled by a microcomputer that uses a GSM/GPRS modem to communicate with the user, providing status reports and live images of the trap. An array of sensors monitors the trap and its surroundings, comprising of infrared light beams and pattern recognition from live imagery. This reduces the by-catch and increases the capture success of the target species. To further increase capture success, we connected a sound system to the microcomputer playing audio baits to attract the target species to the trap. This proved to be useful in the case of large carnivore species occurring at low density. This box trap 2.0 proved to be reliable and safe for big cat species, thus reducing animal welfare concerns by reducing the response time of the team. Our trap has a higher selectivity and efficiency in relation with economic and welfare considerations than other conventional trapping methods.

Collaborations for the development of GPS collars

To answer some crucial research questions, we need to fit GPS collars to the study animals. The collars need to be light-weight, comfortable, flexible and adaptable to the animal movements. They also need to be equipped with the latest developments of technology to collect the most data possible in the most battery-efficient way. It is therefore highly important for us to maintain a close collaboration with manufacturers to exchange experiences and knowledge, and provide detailed feedback. This helps to improving and developing next generation GPS collars while ensuring the best animal welfare standards.

For this, we have established long-term close collaborations with remote download collar manufacturers such as Eobs (www.e-obs.de), satellite collar manufacturers such as Followit (www.followit.se/) and Technosmart (www.technosmart.eu) to develop the best possible GPS collars adapted to the characteristic biology, ecology and morphology of cheetahs.

GPS download stations monitored remotely by GSM-GPRS camera traps

To retrieve data from our collared cheetahs we use both remote download collars and satellite collars, depending on the study area and the research questions to be answered. Retrieving data from remote download collars can be done either by aerial tracking or setting download stations at locations regularly visited by study animals such as marking sites. To reduce hours of aerial tracking flights, which involve costs and potential disturbances to the collared animals, we built a web of download stations located throughout the study area. These download stations retrieve the data from the GPS collars in their vicinity and store them. The data collection from the download stations and the maintenance of them is quite time and fuel consuming. To ensure an efficient use of our resources and reduce our costs, we therefore have designed download stations that are remotely monitored by GSM/GPRS camera traps. The camera traps alert us when GPS data has been retrieved from collared animals providing information from the display of the download station such as the collar identification and the date of download. This way, we can efficiently coordinate our field trips and combining the GPS data collection from the download station with other tasks such as camera trap data collection, electronic box trap maintenance or even immobilizations of captured cheetahs.

Publications reporting on these topics

• Portas, R., Roeder, R. and Melzheimer, J. 2019. Box traps 2.0: smart, efficient and selective to capture wildlife. Poster presented at the Etosha 112 Symposium. 12.-14.06.2019, Mokuti, Namibia. DOI:10.13140/RG.2.2.35795.94248.

• Marker, L., Schmidt-Küntzel, A., Portas, R., Dickman, A., Good, K., Hartman, A., Critescu, B. and Melzheimer, J. 2018. Capture, Care, Collaring and Collection of Biomedical Samples in free-ranging Cheetahs (Acinonyx jubatus). In Marker, L., Boast, L.K. and Schmidt-Küntzel, A. (Eds). Cheetahs: Biology and Conservation. Academic Press, San Diego, California, USA.

• Hofman MPG, Hayward MW, Heim M, Marchand P, Rolandsen C, Mattisson J, Urbano F, Heurich M, Mysterud A, Melzheimer J, Morellet N, Voigt U, Allen BL, Gehr B, Rouco C, Ullmann W, Holland Ø, Jorgensen N, Steinheim G, Cagnacci F, Kröschel M, Kaczensky P, Buveibaatar B, Payne JC, Palmegiani I, Jerina K, Kjellander P, Johansson Ö, LaPoint S, Bayrakçismith R, Linnell J, Zaccaroni M, Jorge MLSP, Oshima JEF, Songhurst A, Fischer C, Mc Bride RT, Thompson JT, Streif S, Sandfort R, Bonenfant C, Drouilly M, Klapproth M, Zinner D, Yarnell R, Stronza A, Willmott L, Meisingset E, Thaker M, Vanak AT, Nicoloso S, Gräber R, Saïd S, Boudreau MT, Devlin A, Hoogesteijn R, May-Junior JA, Nifong JC, Odden J, Quigley H, Tortato FR, Parker DM, Caso A, Perrine J, Tellaeche C, Zieba F, Zwijacz- Kozica T, Appel C, Axsom I, Bean WT, Cristescu B, Périquet S, Teichman KJ, Karpanty S, Licoppe A, Menges V, Black K, Scheppers T, Schai-Braun SC, de Azevedo FC, Lemos FG, Payne A, Swanepoel LH, Weckworth BV, Berger A, Bertassoni A, McCulloch G, Šustr P, Athreya V, Bockmuehl D, Caesar J, Ekori A, Melovski D, Richard-Hansen C, Van De Vyver D, Reyna-Hurtado R, Robardet E, Selva N, Sergiel A, Farhadinia M, Sunde P, Portas R, Ambarli H, Berzins R, Kappeler PM, Mann GK, Pyritz L, Bisset C, Grant T, Steinmetz R, Swedell L, Welch RJ, Armenteras D, Bidder OR, González TM, Rosenblatt A, Kacjel S, Balkenhol N 2019: Right on track? Performance of satellite telemetry in terrestrial wildlife research. PLoS ONE 14(5): e0216223. Doi: 10.1371/journal.pone.0216223.