Thursday, 19 April 2012

Project C-CATS!

Sunday marked the official start of Project C-CATS, a unique approach to acoustic monitoring that will be the first of it's kind to be conducted. Although there have been comprehensive echolocation studies in captive cetaceans, relatively little is known about their wild counterparts. Static acoustic monitoring is often used to detect vocalisations of wild cetaceans, such as clicks and buzzes, but there is limited knowledge of the extent to which various factors such as the animal's distance from the data logger and mooring depth affect the detectability of these sounds. C-CATS will be attempting to monitor harbour porpoises and bottlenose dolphins by simultaneously employing a hydrophone array and static PODs; this will allow us not only to localise and track individual animals through the water column but also to calculate detection ranges for C-PODs.

With calm seas forecast for Monday, there was no time to lose and it was all hands on deck from the very start; on their arrival Winnie, Marta and Katrin, the three research assistants, were swiftly roped in to assist Hanna, the project coordinator, and Luke, the skipper, to prepare the moorings and buoys for the PODS, measuring, knotting, marking and coiling lengths upon lengths of rope. The boat, Islander, also needed some finishing touches to prepare it for it's duty as a research vessel and with the help of Luke, Winnie and it's owners, Hanna and Brett, the seats usually reserved for paying passengers were removed to make space for PODs and other acoustic equipment. In the late evening, Kati, Felix and Jens arrived in New Quay at 10 PM after an arduous two day journey from Germany, joining the rest of the team- just in time for an enormous portion of Chilli!
We were off to an early start on Monday, setting out at 4 AM to deploy 5 pairs of vertical C-PODS, each comprised of one surface and one bottom POD, for a project run by Nik Tregenza, who has agreed to share his data with us. With the moon still high in the sky, we carried the equipment down to the beach which was when we realised that the boat would most likely ground if we drove it onto the beach and loaded it with the weights for the moorings. Not deterred by this unforeseen complication, Kati and Hanna bravely donned their dry suits, while Luke and Winnie brought the boat closer to the beach and the rest of us waded out in wellingtons to pass the weights and other equipment to them so that they could pass it up into the boat.
4am at the harbour, ready to load up the equipment for a days work of deploying C-PODS and T-PODS

Running only slightly behind schedule, we loaded the remaining equipment -and the deployment team consisting of Hanna, Nik Treganza, Luke, Winnie and Katrin- at New Quay pier at about 6 AM and headed out into the bay. The extensive knotting practice from the previous day paid off as stopper knot after stopper knot joined buoys to moorings and moorings to PODs, allowing us to deploy the PODs quickly at their allocated spots under the careful guidance of our experienced team leaders, Luke and Hanna. We were even joined by a pod of dolphins that stayed with us for most of the morning, hopefully providing the first set of recordings! 
Out on the water, Ready to deploy C-PODS

We returned to New Quay in time for an early lunch and a well deserved rest. As the weather was set to turn the following day, however, Hanna and Luke only got a brief respite before heading back down to the harbour with Jens, Felix and Kati to deploy another 6 pairs of horizontal T-/C-PODs, both PODs suspended 2m above the seabed and at least 5m apart, which took the best part of the afternoon and the early evening.

Deploying T-PODS and C-PODs
The deployment of 22 PODs in a day was considered a great start to the project by everyone involved and we decided that we had earned the right to celebrate- by having a very early night.

Tuesday the predicted gale force winds hit New Quay. Confined to dry land, we built the array on land for the first time on Tuesday and realised just how big it was (7m long and 6m wide) and set about discussing the best methods of attaching it to the Islander, an 8m aluminium boat- preferably without causing lasting damage to either boat or equipment. This required a lot of quick thinking, in the truest sense of the word, as it was only feasible to attempt attachment when the boat was fully out of the water, which is only for about 2 hours every day during low tide. After initial frustration and with the tide lapping at our heels, we decided to reconvene the next day and trial a decidedly low tech solution to attach the high tech equipment securely to the boat: ratchet straps.  
Building the hydrophone array to be mounted on 'Islander'

The afternoon provided a real taste of the infamous British weather, sunshine interspersed generously with heavy showers. Jens, Kati and Felix made the best out of a bad situation by staying in the house and setting up the acoustic and GPS equipment so that once the weather turns in our favour, we will be ready to head out on the boat. Meanwhile, Winnie, Marta and Katrin were preparing for their role as cliff observations team. Together with Gemma, another research assistant, they will be responsible for tracking cetaceans near the PODs and the research vessel using a theodolite and keeping the boat team updated of animal positions at all times. Armed with copious amounts of rain gear- and a giant pair of garden shears- Marta, Winnie and Katrin used the afternoon to familiarise themselves with the observation site. Located on the picturesque Ceredigion coastal path, a steep 5 minute climb from New Quay, the site is nestled in between ruins of the old coast guard look out and a large amount of gorse bushes conveniently overlooking the grid of PODs.

The howling winds woke us up several times Tuesday night and by Wednesday morning we were all fairly sure there was no way we were getting out on the water. Instead, Felix spent most of the morning training the cliff observations team, Gemma, Winnie, Marta and Katrin, in the correct set up of the theodolite, or 'total station' while Kati and Jens continued to work on setting up the acoustic equipment in the dining room.
Getting a lesson from Felix in the use of Theodolites
In the afternoon, most other things came to a stop as most of the team made their way back down to the beach to try to attach the array to the boat again. With the help of several styrofoam blocks and a good amount of ratchet straps, we eventually arrived at a satisfactory solution that would allow us to safely attach the equipment, minimise movement of the gear and safeguard the boat as well. Now that we had managed to attach the array, we had time to tackle another problem, keeping expensive electronic equipment safe and dry on a small boat. The answer was simple; the Culticave. A small, fully, collapsable greenhouse which fits neatly on the deck of the Islander, keeps the rain out, the heat in and is also fully see through, making it slightly less of an obstacle for Luke to navigate!

The 'CultiCave'
The afternoon was spent tracking a variety of objects from the front garden (starting with drainpipes, before graduating to cows) - involuntarily also trialling their full outdoor gear in the strong Northerly winds- while the acoustic team was also hard at work fine tuning their equipment. 

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