Protecting threatened Over-seas biodiversity

New innovative action in Mayotte: two Madagascar pond-heron equipped with GPS Argos tags!

In December 2019, the GEPOMAY association equipped 6 Madagascar pond-heron with GPS-UHF solar tags in Mayotte. In December 2020, the association changed its protocol and equipped 2 new individuals with GPS Argos tags, thus ensuring the world’s first mission to equip Madagascar pond-heron with dual Argos and GPS technology.

What purpose? Increase the existing information on the feeding areas of the Madagascar pond-heron, on its reproduction, its habitats and its migration in order to improve the conservation of the species.

Madagascar pond-heron with a GPS argos tag – GEPOMAY

Encouraging first results following the 2020 mission

In December 2020, GEPOMAY association, with the help of a former employee of the association, equipped 2 Madagascar pond-heron with GPS Argos tags. The team also banded 7 juvenile individuals, allowing more information on the ecology and phenology of the species to be learned over the next few years. Two months after the telemetry equipment of the two individuals, the first results show that the device works well and complement the results obtained in 2019 on the distribution of the activities of individuals in 24 hours and on privileged sites:

  • One of the two individuals has remained on the heronry for the moment and is moving towards the surrounding rivers but has started to prospect a little further for a few days.
  • The second seems to always make the same trips so far. GEPOMAY association notably discovered a site where the individual would spend his nights more than half of his time. Of course, it is too early to begin to make any interpretation on these movements and it will be necessary to wait at least a year to start carrying out analyzes. Either way, these are first encouraging news for the conservation of the species.

Madagascar pond-heron © Gilles ADT

Difficult harvest following the 2019 mission

In 2019, GEPOMAY equipped 6 Madagascar pond-heron with GPS/UHF tags. As the weight of the species was not known at the time, the association favored the use of this method of equipment, which is lighter, so as not to risk impacting the species.

Unlike Argos tags, GPS/UHF solar tags require the deployment of personnel to the sites in order to ensure the installation of an antenna that collects and records the data. It is therefore necessary that an equipped individual passes in the field of the antenna. It must therefore be placed in strategic places depending on the period (as a heronry during reproduction and on feeding sites outside the breeding season).

Following the first 2019-2020 mission, the antenna was placed alternately on different feeding and reproduction sites of the Madagascar pond-heron © GEPOMAY

The first results of this mission made it possible to identify the first sites where individuals moved regularly and to accumulate data on the hours of use of known and unknown feeding sites.

Unfortunately, although data could be recovered on two individuals 9 months after the mission, the remaining individuals were no longer captured after a few months. This can be explained by the simple absence of individuals from the places where the antenna was placed, by the possible covering of the solar batteries by the plumage thus preventing their recharging or by the death of individuals.

In order to overcome the constraints encountered following the 2019 mission and now knowing the weight of species, the association decided to equip individuals with GPS Argos tags in order to avoid the panels being covered by plumage, which autonomously transmit the location of the species.

And for 2021?

Following the success of the mission at the end of 2020, new individuals will be equipped in the second half of 2021 in order to have enough data to answer the questions that GEPOMAY is asking and which will allow the species to be protected in the long term.

To find out more about the actions of the Madagascar pond-heron project