Comparative Performance of Three Brands of Lightweight Global Positioning System Collars

Abstract

Recent miniaturization and weight reductions of Global Positioning System (GPS) collars have opened up deployment opportunities on a new array of terrestrial animal species, but the performance of lightweight (,90 g) GPS collars has not been evaluated. I examined the success of 42 GPS collars from 3 manufacturers (Televilt/TVP Positioning, AB, Lindesburg, Sweden; Sirtrack Ltd., Havelock North, New Zealand; H.A.B.I.T [HABIT] Research Ltd., Victoria, BC, Canada) in stationary, open-sky conditions and during deployments on brushtail possums (Trichosurus vulpecula), a nocturnal arboreal marsupial. I assessed performance of these collars in terms of technical malfunctions, fix-success rates, battery longevity, and aspects of location quality. Technical malfunctions occurred in .50% of HABIT and Televilt collars, whereas all Sirtrack collars operated normally. Fix-success rates for all brands were significantly higher during stationary tests than when deployed on brushtail possums. HABIT and Televilt brands functioned poorly in field conditions, with success rates of 16.2% and 2.1%, respectively. Sirtrack collars had the highest fix rate when deployed (64.8%). I modified several HABIT collars by changing the GPS antenna location, with a resultant substantial increase in field fix success (92.6%). Most collars ceased working before they reached 50% of their manufacturer-estimated life expectancy. Suboptimal placement of GPS antenna, combined with short satellite acquisition times and long fix intervals, were a likely cause of low fix-success rates and premature battery failures. Researchers wanting to employ lightweight GPS collars must be aware of current limitations and should carefully consider prospects of low fix rates and limited battery lives before deciding whether these units are capable of meeting study objectives.

First known satellite collaring of a viverrid species: preliminary performance and implications of GPS tracking Malay civets (Viverra tangalunga)

“…Overall fix success rate was similar to the performances of other small, field-deployed GPS units (Haines et al 2006;Blackie 2010;Recio et al 2010;Brown et al 2012). Large variability of GPS fix success rates between tracked individuals (22.0-88.3 %) is a commonly documented trend in satellite tracking, and could be attributed to the specific behaviours of collared animals (Blackie 2010;Mattisson et al 2010;Recio et al 2011a). Collar-bearing civets utilised a range of microhabitat types, with some individuals (Males 3, 4, 6-8) residing in areas of greater undergrowth and canopy densities than others (Males 1, 2).…”

“…Additionally, when GPS collar failures do occur, they are considerably more costly in both value and relative data loss than VHF failures. A large amount of GPS collar failures have been documented in field-deployed scenarios (Blake et al 2001;Johnson et al 2002;Gau et al 2004;Hebblewhite et al 2007;Blackie 2010). In this study alone, 22 % (n = 2) of deployed GPS collars failed.…”

“…Most terrestrial GPS studies have focused on mammals >7 kg, so spatial research on small and medium-sized species relies on VHF transmitters (Blackie 2010;Cagnacci et al 2010). Owing to recent advancements in both battery longevity and the miniaturization of GPS component design, long-term satellite technologies are being applied to increasingly smaller mammalian species, such as the ocelot Leopardus pardalis (Haines et al 2006), European hedgehog Erinaceus europaeus (Recio et al 2011c), fossa Cryptoprocta ferox (Lu¨hrs and Kappeler 2013), fisher Martes pennanti (Brown et al 2012), and brushtail possum Trichosurus vulpecula (Blackie 2010;Dennis et al 2010).…”

Home Range and Habitat Use of Santa Rosa Island Foxes (Urocyon littoralis santarosae)

“…Island fox populations are recovering with higher densities and survivorship on most islands, and some of the subspecies are on the way to being delisted Frair et al 2010, Blackie 2010. While GPS collars are more expensive (~5x the cost) than conventional VHF collars, the increased quantity of data and time savings cost-efficiency is far superior to VHF collars.…”

“…King, Catalina Island Conservancy, personal communication). As a result of the limited availability of miniaturized GPS technology, very little performance testing has been conducted (Blackie 2010). Most performance testing has been done on larger GPS units, which are not limited by battery size.…”