Silence of the sunfish

sunfish cartoon

Since the tagging of sunfish Giorgio, I had hoped that sunfish season was about to begin in earnest… (usually by this time of year, the fishermen are pulling 500 fish from their nets a day) however working with wild animals can be unpredictable to say the least. So unpredictable that after 10 years of catch data showing that this is peak sunfish season, there have been a total of 0 sunfish in the nets in the past week!

The other frustrating aspect of tagging wild fish, is trying to recover the tags… which is proving a little tricky to say the least! The sunfish harness we used for Giorgio is equipped with a satellite tag, which provides approximately one accurate location every 24 hours (see below map of sat tag positons over the last week) and then we arrive in the area, we use a radio tag to hone in on the harness (see photos of radio tracking). Sounds pretty simple, but the devil is in the detail!

Giorgio sat tag movements

The elusive tag…

We could hear the radio tag bleeping for the first few days of searching, and the louder the bleep, the closer you are to the harness… but due to limited boat time and poor weather conditions, we were unable to retrieve it on our first few attempts. Then the tag went silent… not a good sign. It is possible that the tag’s waterproof housing has failed and the electronics have short circuited or perhaps it has become tangled etc.

But still we should be able to use the satellite positon to get close and then conduct visual surveys to locate the harness right? Wrong again! High winds over the last few days have made visual surveying difficult and even dangerous. On our last trip out, Nick and I got caught out by a sudden squall and were facing waves big enough to wash over the top of our little boat, sending it nose ploughing into the water! We were forced to shelter in San Fruttoso (a tiny inlet on the exposed side of the Portofino peninsula) and make a mad dash back home before the wind got stronger. We even saw a huge water twister on the horizon!

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Cold, wet weather on fieldwork?! What happened!

Drama over, the satellite tag then fell silent as well for 4 days, which was enough to make me fear the worst, that the harness had sunk or been destroyed by a passing freighter… but, this story may have a happy ending yet! Today, the satellite tag has made contact once again! It has drifted further north and is now floating some 2km offshore from a little town called Sori, so I hope that with better weather on the horizon, that I will be out again very shortly to go and collect the first sunfish acceleration data! Wish me luck (I think I need it!)

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No dry clothes…

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