New Zealand's public conservation agency, the Department of Conservation, (DOC), is testing the system by tagging three Hector's dolphins.
These animals are also endangered, but are more populous at around 7,000 than Maui's dolphins, which number less than 150.
If the trial of the satellite tags proves successful on the Hector's dolphins, then the critically endangered Maui's may also be tagged.
This, the DOC argues, would give it sorely needed information about where these small cetaceans range.
"Our efforts to save New Zealand's rarest dolphin are being hampered by what we don't know about them," said Rob McCallum, from the Department of Conservation.
Local conservation groups are vehemently opposed to the trial.
Netting ban
Maui's dolphins are now protected through a ban on the use of commercial set nets within four nautical miles of the west coast of New Zealand's North Island, where the dolphins are known to live.
With less than 150 Maui's dolphins left, we need to consider all means available to find out what we need to know to save this dolphin. We can't afford to wait ~Rob McCallum, Department of Conservation
In the past three and a half years, eight Maui's dolphins have washed up dead.
But since the netting ban came into force late in 2002, only one has been found dead.
The worry for the DOC is that the dolphins have been spotted well outside the protected area, as far as 15 nautical miles from shore and up to 100 kilometres south of the closed set netting area.
"We need to find out if Maui's dolphins move outside the current set netting closed area," said Mr McCallum.
"If so, we need solid evidence to show this and to determine how much of their time they spend in different areas."
Internationally, scientists have tagged other marine mammals, often with startling results.
Heaviside's dolphins, a close relative of Hector's dolphin in southwest Africa, were thought to be an inshore dolphin species.
Satellite tagging has shown that this dolphin species moves out to and back from the edge of the continental shelf, about 25 nautical miles offshore.
Ideal tags
To test the efficacy of satellite tracking on the South Island-based Hector's dolphins, the DOC plans to attach tiny satellite tags - two matchboxes in length and 50 grams in weight -to the dorsal fins of three dolphins.
The transmitters are attached with nylon-coated pins, with fasteners that are designed to eventually corrode and release the tag from the animal.
For the transmitter to work, it needs to be above water, so the trial aims to find out if the swimming style of New Zealand's small dolphins, which do not dive very deep but do not surface for long, will allow enough useful data to be transmitted.
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