Download GNSS to Study Seabirds` Island

© Luís Ferreira
GNSS to Study
Seabirds’ Island
by Luís Santos
Several hundred kilometers to the south of
Madeira lie the Savage Islands (Ilhas Selvagens),
home to some rare species of seabirds. This
untouched ecosystem is a sanctuary for the
marine birds that come here to breed. But the
peaceful appearance can be deceiving, as climate change appears to be having an effect on
the birds’ behavior. A Leica Geosystems GNSS
reference station with several connected meteorological sensors is supporting ornithologists’
research on this remote island.
At the beginning of 2011, Leica Geosystems provided
a turnkey GNSS reference station solution to DRIGOT
(Regional Directorate for Geographic Information
and Land Planning) to be installed on the remote
island of Selvagem Grande. In August, after discussing and solving all of the logistics aspects, DRIGOT’s
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team travelled to the island to install the GNSS reference station and other components. As there is no
regular transport to get there, the team got a 14
hour lift with the Portuguese Navy.
Since there is also no electricity on Selvagem Grande,
a custom designed solar/wind system was built to
supply all system components with sufficient power.
According to the consumption needs of each sensor, a set of three solar panels was included, as
well as two gel batteries to maintain system power
overnight. An originally planned wind generator was
dropped from the power supply system due to the
high risk of putting the local young bird population at
risk through its presence and noise.
A Leica GRX1200 Pro receiver and a Leica AR25
choke-ring antenna were installed and connected
to the autonomous power supply. Furthermore, the
solution included a MET4 meteo station. GNSS and
meteo data are pushed via the satellite Internet connection to the Leica GNSS Spider server installed at
the DRIGOT headquarters in Funchal (Madeira), which
also manages the Madeira GNSS network REPGRAM.
The GNSS raw data collected on the island is of major
relevance to geodynamic studies of the region, as it
represents the behavior between Madeira and the
Canary Islands. This data is used for scientific purposes by Portuguese universities as well as some
international institutions and universities, such as
EUREF and IGS.
Since the meteorological data was one of the main
products demanded in this project, a high accuracy
meteorological sensor, the Paroscientific MET4, was
installed on site. Temperature, atmospheric pressure,
and humidity are recorded every 10 minutes, and are
a fundamental tool for all major scientific studies
taking place on the island, in particular ornithological studies. The global climate has warmed up, and
all models point towards this being the trend for
decades to come.
These changes in climate are affecting the distribution and phenology of countless species. It is vital
to study and better know the links between these
changes and the behavior, physiology, and demography of top predators, such as Cory’s Shearwater.
The demographic data collected over the past 30
years on Selvagem Grande Island will be correlated with past climate data to better understand the
demographic responses of the Cory’s Shearwater
population. In the future, with the availability of very
accurate meteo data, the main task will be to create
new models that help better understand the population trends, to be used as a reference point for
future comparisons.
The preliminary analysis of the GNSS data collected
reveals that the Leica GRX1200 Pro and the Leica
AR25 choke-ring antenna are providing GNSS measurements of superior quality.
About the author:
Luís Santos is a Surveying Engineer and is a Leica
Geosystems GNSS and HDS Product Specialist in Portugal. ([email protected])
Maria João Seiça Neves ist Regional Director at
DRIGOT. ([email protected])
Selvagens Islands
Nature Reserve
The Selvagens (“Wild”) Islands are situated in the
North Atlantic, 163 nautical miles from Madeira
Island, including three volcanic islands, Selvagem
Grande, Selvagem Pequena and Ilhéu de Fora. The
terrestrial and marine biodiversity of the Selvagens
Islands as well as the importance of their habitats
make these islands a unique Nature Reserve.
The fauna of the Selvagens Islands is diversified,
mostly for nesting birds. The nature reserve is a
refuge for an interesting community of several species of seabirds such as Cory’s Shearwater, the largest colony of this species in the world, White-faced
Storm-petrel, one of the largest populations in the
Atlantic and forms the northern boundary of the
species distribution, Bulwer’s Petrel and Madeiran
Storm-petrel.
More information about Madeira´s protected areas
can be found at: www.pnm.pt
More information about Madeira can be found at:
www.geocidmadeira.com
For more information about the Madeira’s GNSS
reference service REPGRAM, please visit:
www.repgram.org.pt
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