Satellite tagging or telemetry uses cutting edge technology to discover how manta and devil rays use their 3D underwater worlds.
Understanding the finer details of a manta ray’s life, such as where they breed, how far they travel and when, enables scientists to assess the types of threats these animals and the wider population are exposed to and importantly how best to protect them.
Tags are an amazing research tool and depending on the type of tags used, scientists can quickly gain valuable insight into their subjects’ movements and associated behaviours that otherwise would remain a total mystery.
Edy Setyawan, 2021
Edy Setyawan, 2021
SATELLITE TAGS ARE INVALUABLE FOR SPECIES AND POPULATIONS THAT WE COLLECTIVELY KNOW VERY LITTLE ABOUT AND CAN BE CHALLENGING TO STUDY, SUCH AS OUR VERY OWN MANTA AND DEVIL RAYS.
Unlike other research methods such as photo identification, satellite tags are expensive. However, the data accuracy and speed in which this data can then be utilised is currently unmatched by any other technology. It’s also important to note that attaching tags to any animal, including manta rays is invasive. It is therefore very important that the reasons to tag an animal are robust and that the findings from this research will have a significant positive impact on that species’ and/or population’s conservation management.
All tagging research conducted in New Zealand is carried out by highly experienced taggers and under a strict permitting process issued by the Department of Conservation in conjunction with an independent Animal Ethics assessment.
Satellite tags are essentially little computers that can be programmed to continuously record environmental data, such as water temperature, depth, and light levels. Tags are attached to a tether and then deployed by a hand spear. This technique allows the tagger to carefully control the tag placement and force required to attach the tag via it’s anchor to the manta ray’s dorsal surface.
Once attached, satellite tags can only transmit data when their antenna breaks the water’s surface, which they transmit to the ARGOS satellite network. Therefore, a manta fitted with a satellite tag does not necessarily allow researchers to track its movements in real time because manta rays spend most of their time below the water’s surface. Instead, many satellite tags are designed to archive their data, storing information as the manta goes about its daily activities.
Currently, two types of satellite tag have been deployed on oceanic manta rays in Aotearoa NZ as part of a collaborative research project between Manta Watch New Zealand Charitable Trust, Conservation International Aotearoa, University of Auckland, the Department of Conservation and Tindale Marine Research Charitable Trust.
There are extensive tag options to choose from depending on your chosen species and the environmental monitoring you are wanting to do. Here’s a quick summary of the satellite tags used for our NZ manta research:
MiniPAT or Pop-up
|Tag duration:||Tags are programmed to release
and pop off after 6 to 12 months.
|Anywhere from 1 week
to 4 months
|Type of data recorded:||Water depth, temperature and
geolocation using ambient light levels
and the time of sunrise and sunset.
|Water depth, temperature, and
highly accurate GPS position data.
|Data accuracy:||Accurate dive data, however horizontal
movements or tracks are estimates.
|Data and tracks 100% accurate
SPLASH tags use advanced fast lock
technology to take a snapshot of all
available GPS satellites and record an
accurate position fix in under a second.
|Data transfer:||No data is transmitted until the tag
has popped off the manta and is
floating at the surface.
|The tag will attempt to
transmit data whenever at
|Highlight:||Highly buoyant tag with streamlined
shape with little drag ensuring longer
deployment times that can reveal a
whole year in an animal’s life.
|Data can be received from the tag via
the ARGOS network whilst it is still
attached to the animal.