Monday- If you fail at first, try, try,
try and TRY again!
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The new calibration point |
With the weather forecast promising a
good weather window on Tuesday, Monday was a day of last minute
preparations. The cliff observation team headed up along the coastal
path with Felix to measure the calibration point for the theodolite
as well as the position of the buoys marking the location of the
PODs. While Marta and Winnie began measuring the position of the
buoys, Felix and Gemma set off to measure the calibration point for
the theodolite; a white MOD trailer located further down along the
coast. Unfortunately, this expedition was soon met with
complications; possibly because it is the property of the Ministry of
Defence, Gemma and Felix could not get close enough to measure it.
Not wanting to compromise national security but in desperate need of
a measurable reference point that would allow us to calibrate the
theodolite, the decision was made to choose a new point, a large
corner fence post. Changing the reference point, however, meant that
all buoy positions Winnie and Marta had been busy measuring, now
could not be used anymore and that all measurements would need to be
redone. Although initially frustrating, it was still a good exercise,
allowing the cliff observation team to get familiar and comfortable
in the use of the theodolite.
Later that day, it was still too rough
to take the boat out but the team spent most of the afternoon
preparing the Islander for the promised lull in the wind. The famous
'Culticave', was also allocated a permanent position on the boat and
was successfully set up and secured on deck. Felix also used this
time to measure the boat and array with the inertial measurement
system which compensates for the rotation roll, pitch and angle of
boat as well as measuring the angle to the north during acoustic
recordings, this way we will be able to tell how the roadie bar is
aligned at all times. However, these measurements had to be cut short
due to the quickly rising tide. On dry land, once again, Winnie,
Felix and Jens spent a long evening disentangling hydrophone cables,
ensuring they were coiled separately and safely and ready to use the
following day. After a long day, the team headed home, hoping for
better weather for Tuesday.
Tuesday- All systems go!
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Preparing the acoustics equipment |
Tuesday was the big day, the window of
opportunity we had all been waiting for! With the wind predicted to
be at an all time low in the afternoon, there was an air of
anticipation around the house as everyone did their bit to ensure
that the first run with the full hydrophone array would be a success.
The array was assembled on the pier,
and for the first time, the hydrophones attached! All electrical
equipment, 2 laptops, batteries, the recording unit and amplifier,
was assembled under the protective cover of the Culticave.
Originally designed to be a greenhouse, it also very efficiently
retains heat, which may prove to be a bonus on cold days, but was a
bit of a concern in Tuesday's atypically sunny weather with not only
all electronics but also Jens and Felix squeezed snugly under it's
protective plastic roof! Finally, after breaking for a well deserved
lunch in the sun (including home made cream tea courtesey of Hanna
and Kati!), the cliff observation team, Marta, Winnie, Gemma and
Katrin, set off to prepare the site while the boat team, Hanna, Luke,
Felix, Jens and Kati, made last minute adjustments, ready to set off
as soon as the last white caps disappeared from the horizon.
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Calibrating the theodolite |
Having had plenty of time to practice
on the friendly neighbourhood cows, and encountered and resolved many
error messages under the careful guidance of Felix, the cliff team
confidently set up the theodolite- just to be set upon by error upon
unknown error! Undeterred, they consulted the manual, made notes and
tried the well known 'switch it off and back on again' technique,
before resorting to calling Felix on the boat who swiftly resolved
the issue once again. Calibrated, centred and ready to go, the team
was now ready to record the positions of all the buoys marking PODs
(all of which were present and intact despite the scare with
Patricia!), as well as scanning for cetaceans and keeping an eye on
the Islander.
Meanwhile on the boat, the first trial
run with all hydrophones in the water was in full swing and although
there were no animals in the vicinity to record, the boat team
successfully recorded and located the echosounder using the acoustic
array! Despite the limited practical application of this achievement,
it was nevertheless a very important step forward, as it allowed the
team to test whether the equipment was working correctly. They also
had some time to attempt the first playback experiments; playing back
sounds with the aim to study the likelihood of the static PODs
picking up sounds at different volumes and distances. In the early
evening, with storm clouds gathering overhead, the wind picking up
again and the rumble of distant thunder in everyone's ears, both
teams headed home after a successful day!
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Islander as viewed from the cliff top observation point |
Wednesday- Gone with the wind-again
All hopes of resuming boat or cliff
based work were literally gone with the wind early on Wednesday
morning. As gale force winds racked New Quay, there was little to do
but to resign ourselves to the fact that we would be confined indoors
for most of the day. However, as always there was plenty of odds and
ends to do -such as updating the blog and replenishing our diminished
food supplies as well as downloading data from the theodolite and
working out the kinks in the electronic set up.
In the afternoon, Felix, Luke and
Katrin headed back down to the Islander to complete the inertial
measurements during low tide. Waiting patiently for the waves to
retreat, the flooded 'Culticave' was dried out and the electrical
equipment set up while further storm clouds gathered overhead. Slightly
concerned about this development, as some of the measuring equipment
is sensitive to water, the team checked the time to gauge how much
time they had to complete the measurements- only to find that low
tide had come and gone and at no time had Islander been completely on
dry land! Unfortunate as this development was, we
resigned ourselves to the fact that the weather and tides were not
under our control and headed back home.
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Waiting for the low tide that never was! |
Meanwhile, Hanna had checked the
weather and discovered a brief good weather window early on Thursday
morning- however just how early 'early' was remained a matter of
mystery and much discussion for a while. We did not have long to
dwell on this somewhat ominous announcement as Jens commanded all our
attention for a pre-dinner talk on TOAD; Time of Arrival Difference,
the method used to localise vocalising animals using a hydrophone
array. After dinner the real meaning of 'early' was finally revealed
and we headed straight to bed to be awake- bright and 'early' the
following morning!