Table 1.

Key challenges for developing real‐time poaching‐alert systems. See main text for possible solutions to some of these problems

(a) Technological challenges
Poaching sensor	Sensors must trigger reliably, which requires extensive pre‐deployment testing; sensors must trigger quickly – detecting lack of motion alone (e.g. with old‐fashioned ‘jitter’ mortality switches) is insufficient, because of unacceptable time delays (see main text); some sensors (e.g. heart‐rate sensors) would require invasive procedures, such as (electrode) implantation, with possible effects on subjects’ welfare and on tagging speed (see below)
ad hoc data generation and transmission	Tags must generate (GPS) coordinate information and transmit alerts to satellites and/or ground receivers, before they can be destroyed by poachers; bandwidth is likely to be an issue and will necessitate data compression; where mobile phone networks are not available, dedicated infrastructure may need to be set up
Battery power	Tags’ batteries should last as long as possible, to minimize the need for retrapping subjects (see below)
Tag attachment	Tags must be attached to animals in a way that they are well concealed and achieve reliable sensor readings, without causing undue burden; invasive procedures (see above) will increase handling time, potentially hampering efforts of mass deployment (see below)
(b) Other challenges
Permits for deployment	Some drone‐based projects experienced problems with obtaining permits for deployment; support of local authorities, and other stakeholder groups, is required
System costs	System costs should be minimized, to facilitate mass deployment
Trapping effort	A large proportion of animals must be (perceived to be) tagged, for establishing a successful deterrent function; this may be possible in small, extensively managed populations, but would be difficult in vast patrol areas; efforts of mass deployment would benefit from low system costs (see above) and straightforward deployment techniques (see above)
Infrastructure requirements	Anti‐poaching units must be able to reach remote crime scenes quickly, once an alert has been raised by a system; this will usually require the use of helicopters
Sentencing of apprehended poachers	Real‐time poaching‐alert systems can only become a major deterrent if they increase the chances of arresting poachers, and if arrests lead to successful prosecution and appropriate sentencing; local authorities need to ensure the latter