Introduction
You only can protect or monitor a species if you know their ecology and behavior. Knowledge of the ecology and behavior of species is necessary to understand their needed environment. If the needed environment is known, protection and conservation of the species could be improved. To investigate this you have to investigate the species in their natural habitat without influencing or disturbing them. If devices or observer influence the behavior the results are not representative.
Remote methods like data logger are an opportunity to get insights into species habitat use, home range, activity and physiology (Scheibe and Gromann 2006; Cagnacci et al. 2010; Shamoun-Baranes et al. 2012). To have a representation of the natural behavior and movement, the studied animals have to be fitted with different devices collecting indirectly (without a direct observer) data. The attachment has to be noninvasive/nonsurgical and cope with the different behaviors of the animals. Up to now, there are several solutions for many species using different attaching methods for example with collars, backpack systems or on glued
devices[BL1] (
\cite{warner_simple_2006}Warner et al. 2006; Warwick et al. 2006; Doody et al. 2009; Flesch et al. 2009; Rautio 2015). Finding the right method is challenging in small light weight species (for example small lizards, lightweight birds and small mammals) because the weight of the systems has to be considered often resulting in short battery lifetime. Additionally, in some devices data can not be downloaded from the distance so the devices have to be de- and reattached periodically. However, this is even more challenging for hedgehogs (
Erinaceus sp.). Hedgehogs are between ca. 600 to 1500g in weight depending on the season (QUELLE). They are mobile living in dense vegetation and have a special defensive behavior (curling up). Due to all this traits and behaviors usage of usual collaring and applied attaching methods are not possible. Additionally to the species related challenges, flexibility in attaching and removing devices is necessary to cope with short battery lifetimes or to react to unknown circumstances to protect the health of the animal if negative effects are visible.
In this case, we report an attaching method for European hedgehogs (Erinaceus europaeus) similar to Recio et al. (2011). In their study, a leather base plate combined with a GPS data logger and VHF transmitter was glued to the back of the animal. However, this system was used no longer than 8 days and was with 7.5x3x2 cm (length x width x height) leather base and a weight of 39 g relatively big in size. With the progress in technical development, it is now possible to create smaller devices but the lifetime of the battery is still limited due to the weight of the battery systems. Solutions for short battery lifetime are circumvented using solar panels, but these are not usable for night active hedgehogs. One possible solution is, to allow attaching and detaching of devices while leaving the system as a backplate on the hedgehog. Thus, an increase of study time is possible by minimizing the weight and therefore possible negative effects on the hedgehog's behavior or health. Even devices which have to be detached to download the data can be used and reattached afterward. The aim of this study was to use the approach of Recio et al. (2011) and improve it for the before described traits. Here we used acombination of VHF transmitters and other devices and an easily attachable and detachable system, which makes it possible to react to unknown circumstances and reload the devices with a short battery lifetime, without having an effective handling time of more than 1 min.
[BL1]Danach KANN noch ein Kapitel kommen, in dem du kurz (2-3 Sätze) zu Untersuchungen zur unterschiedlichen Anbringung von Geräten am Tier berichtest, die alle (ich kann Dir da gern Literatur geben) gezeigt haben, dass minimale Gewichte oder verschiedene Positionen am Tierköper maximale Vehaltens- oder Energieverbrauchsveränderungen bewirken (hab Dir dazu ne ganze Menge Paper in den Dropbox-Ordner gepackt). Damit kannst Du auf die Wichtigkeit Deiner Studie (was kann man an der Besenderung selbst verbessern)