Field WORK
Land Survey
Theodolite
During the first week, I did two land surveys. Having never done land surveys in my life before, the team introduced me to the theodolite. The theodolite is a precision optical instrument that allows us to measure angles between designated visible points in the horizontal and vertical planes. In order to be able to use the theodolite, we have to position it at a particular reference point that we chose (these points have been marked by DMAD before with some paint on the ground to make the installation of the theodolite faster when we arrive on-site). Then, after levelling the theodolite, we have to aim at another reference point, also defined before.
This time we have to look through the theodolite to this reference point and set the coordinate as a reference point on the machine. By referencing two known points we can easily triangulate the position of dolphins through the theodolite.I was very happy to learn how to use this scientific instrument. Having encountered it many times in my academic life I always wondered what was its purpose and how can I use it. Now I know.
Data Sheet
The datasheet is very important during surveys. ACting as a lab book, all the behaviour of spotted dolphins must be written in it every 5 minutes. Informations written in the datasheet are:
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ID number
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Species
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Group number
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Behaviour
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Response to surrounding boats
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Nearest boat
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Type of boat
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The action of the boat
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Pythagoras
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Pythagoras. It´s mapping software. When a dolphin is spotted, we put the coordinate displayed on the theodolite in this software. We add the group of dolphins, behaviour and all the environmental parameters of the moment and we get an accurate map of the survey of the day. It´s a very useful software that I will probably use in my future research. I am very happy to have learned how to use it.
Binoculars
The art of looking through the binoculars requires patience and stability. Other than that there is nothing complicated about it. Always one or two observers with the binoculars during surveys.
Run Down Of What happen in the Heat of the Moment
It first started at the binoculars, Natalia spotted a small pod of dolphins far away. After describing to everyone: number, position, direction, species, the person responsible for the datasheet (me, at that time) wrote every 5 minutes a series of information going from dolphin behavior to proximity of the closest boat.
In the meantime, Cedric, with the theodolite was trying to find the GPS point of the Dolphin and communicate it to Noemi who was in charge to write them in Pythagoras (glocalization, conversion software).
This had to be repeated as many times as possible to have as much accurate data on the Bottlenose Dolphin pod present at that time. Without a clear system, good teamwork, this task is completely impossible. Repeating this exercise three times a week made my communication skills more efficient.
Boat Survey
The Boat
Boat survey are really similar to land surveys. In fact they are the same. The only difference is that we can use the acoustic probe while doing it and photo identification can be realise.
This picture is a perfect representation of a normal day at the station. Everything can change at the last minute. Waking up at 4 am to go on a boat survey, arriving at the boat to find out that the starter is not working. No boat survey.
It is 5 am, what do we do, we drive to another location and we do a cool land survey where we were able to spot 3 dolphins!!!!! Adaptability is key here.
Acoustic Probe
I saw for the first time the hydrophone that we used during boat surveys (when dolphins were spotted nearby). It's composed of a digital recorder, a hydrophone a 10-meter cable, and a 3.5mm jack.
