University of St Andrews SMRU Instrumentation
SMRU Instrumentation
Sea Mammal Research Unit

GPS SRDL (Argos)

For applications needing high positional accuracy where no GSM phone network is available. The GPS SRDL adds GPS quality locations to the standard SRDL.


  • GPS quality locations at a user-controlled rate
  • Relays an unbiased sample of dive and haulout records

Fastloc GPS offers the possibility of attempting a location at every surfacing. Less than a second is needed to acquire the information required for a location. The tag also uses precision wet/dry, pressure and temperature sensors to form detailed individual dive (max depth, shape, time at depth, etc) and haulout records along with temperature profiles and more synoptic summary records as in standard SMRU SRDLs. Both location and behavioural data are then stored in memory.

TDR capability

Automatically retains a continuous record of sample data, which can be retrieved by bluetooth link if the tag is recovered.
  • Depth and temperature (4 sec sample rate)
  • All GPS fixes at user-defined rate (typically 5 - 20 minutes)
Argos/GPS Tag isomorphic image


  • Longevity: typically 3-6 months.
    Lifetime may be extended by collecting GPS fixes for a shorter period and using subsequent transmissions to relay them.
  • A solar-powered option is available with adaptive sampling strategy.
  • Size: 10.5 x 7 x 4 cm
  • Weight: ~370 g

Further technical details: SRDL 9000x Specification (PDF)

Graph showing expected GPS/Argos tag longevity

GPS SRDL longevity

For details of pricing and how to order, please see our Contact & Sales section.
top of page