Following our initial testing of the high-contrast panels last May, we were able to start work on our gillnet mitigation measure trials in earnest in the early autumn.
In October, we attached the panels to the nets of one the collaborating fishing boats. However, due to the abnormally high temperatures in Portugal and lack of rain, the water was extremely clear. The fishermen were therefore unable to use the fishing nets, as they rely on turbid water conditions to make the nets invisible to their target catch – seabass. So, we actually found ourselves in the unusual situation of waiting for weather conditions to take a turn for the worse! And then we waited some more….and some more. Finally, at the end of November, the conditions were suitable to trial our modified gear.
It really is a case of ‘good things come to those who wait’ – the first trips went well and there were no major differences in fish catches between the control and panel nets – this is a very good sign and it is in line with the trials in Lithuania. No seabird bycatch was recorded on these first trials.
So far, so good! However, in the early days of January, the weather continued to worsen, and the sea became very rough. Our experimental nets became entangled on the rocky seafloor, resulting in serious damage to the gear. It was disappointing after all the effort and difficulties we encountered, but the skipper of the boat remains open to trying alternative mitigation measures to tackle the problem of seabird bycatch. On a more positive note, we also started collaborating with another boat at the same time and we had still yet to trial the gillnets during the season due to the unfavorable conditions already mentioned.
The cooperation of fishermen is essential for reliable results and for future adoption of mitigation measures. Fortunately, the fishing crew was happy to help and accepted the challenge of attaching the panels with us.
After the modified gear went into the water, we noticed again that some panels were lost, but not to the extent recorded in the severe weather. It’s important to continue testing different materials and to find which works best in the water – while the materials we are using were effective in the calmer waters of the Baltic Sea, they might not be so appropriate for the open and wild Atlantic. We are crossing our fingers for the right weather conditions, so we can continue this work along with the fisherman. Meanwhile, we continue to monitor seabird bycatch in the area, to better understand its patterns of occurrence.
This is the first time we are trialing such innovative measures in Portugal and we hope the results will contribute to the evolution of gillnet bycatch mitigation, and represent a major step forward for seabird conservation.
By Iván Gutiérrez and Elisabete Silva, SPEA Bycatch Observers.