Last month I returned from sea after two back-to-back trips where I tested the efficiency of mitigation measures in reducing seabird mortality on longline hooks. Similarly Martin was at-sea at the same time performing the same experimental work on a different vessel.
As well as participating in the capsule experiment (see previous diary entry), our main aim was to finish the collection of at-sea data that we started this time last year. The experiment was set up to identify whether tori lines reduce seabird mortality in pelagic longline fisheries. We have had the full support from Pelagic Resources Department of the National Department of Aquatic Resources to carry out our studies and on completing the studies the results look very promising.
From the data we collected in 2009 we felt sure that we were going to be able to show confidently that our mitigation measure was effective, but we knew we would need more data to make firm conclusions. During 2009-10 we completed eight fishing trips on commercially-rigged vessels. During days when longline gear was set without using a tori line, a total of 25 birds were caught. However, on lines set under the protection of a tori line not a single bird was killed.
The tori line did become entangled with fishing gear on a high proportion of the days it was used. In these cases the weak-link we have included close to the end of the tori line breaks and the rest of the tori line is left flying and still prevents seabirds gaining access to the baited hooks.
We are very pleased with the results as they show that the tori line is efficient at reducing seabird mortality in Uruguay, and as such we have a mitigation measure that we can apply to prevent seabird bycatch.
Obviously we still have a lot to do, including testing ways to increase the sink rate of fishing gear, and improving the use of night setting as a standard practice as these measures are complimentary and work best when used in combination.
For the tori line, we need to reduce the entanglements to make sure it is a measure that the fleet will use voluntarily and achieving this is a big challenge for 2011.
Beyond the positive results we were also paying close attention to the different species that attend the vessels and we had some interesting visitors. Two species in particular caught my attention. The presence of the Wandering albatross, which were around the vessel on every day of my time at sea, arrived in groups of several individuals. We see a peak in abundance of this species at this time of year in Uruguay as the female birds from the South Georgia population are starting to leave the chicks on the nests and head up to feeding grounds off Uruguay.
The other species that caught my eye was the Sooty albatross. To date, Martin and I have few records of this species in Uruguay, which has prevented us from identifying a seasonal trend. The closest breeding populations are at Tristan da Cunha and Gough Island, an oceanic archipelago and home to huge numbers of seabirds.
Many species, such as the Spectacled petrel and Yellow-nosed albatross arrive here from the archipelago and so we had imagined that the Sooty albatross would be associated with the same migration. Fortunately these last trips provided plenty of new data on this species, and helped me understand more about where they forage.
Such new experiences are common during trips at-sea on fishing vessels. There is always something new to learn about albatross and petrels in the South Atlantic and this, without doubt, is what gives me a lot of motivation to continue working onboard and observing these magnificent birds.
Continuing with the tori line experiments in the pelagic longline fishery, I headed back to sea but this time aboard the RS Aldebran, Uruguay’s research vessel.
On this last trip we spent 20 days at sea, with a short break at the start due to a faulty hydraulic pump forcing us to return briefly back to port. We headed out into awful weather, with the whole crew suffering seasickness but after three days the ocean settled down and we were able to begin working under more comfortable conditions.
The vessel set eight fishing lines, each as the sun was setting. Of these, four were set using a tori line and four without, as stipulated under the experimental design. These sets reaffirmed how effective a tori line can be on reducing seabird interactions, as we unfortunately caught some birds during the sets with no tori line whereas we caught no birds during the sets with a tori line.
Despite the occasional entanglement, which can happen when the tori line crosses over the main fishing line in pelagic longline fisheries, this mitigation measure worked well at reducing the possibility of seabirds accessing baited hooks.
We believe that we have advanced, from a point when we had no evidence to show that tori lines were an effective measure in pelagic longline fisheries, to the current situation where we have the data to prove it. Now we just need to make some improvements to help prevent entanglements between the tori line and the fishing gear.
We also compared the interaction between the seabirds and the fishing gear as the fishing line is set, during the short period of light available before nightfall. This information provides further evidence as to how the tori lines force the seabirds away from the baited hooks.
After the initial bad luck of the weather conditions, we put in some good work to obtain these results and everything started going well for us. However, once I was dropped back in port, the luck turned against the crew on the next trip as a fire broke out in the engine room. They were able to put the fire out rapidly, but it took them two days to repair the engines and get the vessel back to port, so while I was lucky, it was another difficult day at sea for the crew.
From the 30th November to the 2nd December 2010, the ATF in Argentina and the Universidad Nacional de Mar del Plata-CONICET organised the second intensive observer training course for Indentification
and Recording of Seabird Interactions with Fisheries. The course was intended for fishery observers from the Commercial Vessel Observer and Sampling Programme of the National Fisheries Investigation and Development Institute (INIDEP) and was held in Puerto Quequén through the Argenitean Museum of Natural Sciences, Bernardino Rivadavia to the south of Buenos Aires.
During the first two days, Sofia Copello and Juan Pablo Seco Pon from the Vertebrate Laboratory along with myself (ATF Argentina) presented topics related to the urgency of seabird conservation with particular emphasis on albatross and petrels. We then went on to work through seabird identification in Argentina, specific protocols for fisheries and an introduction about mitigation measures. The observers were then given group activities to complete, including the production of their own seabird identification key which were then presented to the whole workshop.
We trained ten observers with different levels of experience onboard vessels, some recently starting in the programme and others with over 12 years in the job. We handed out electronic and laminated versions of educational materials aimed at informing the observers on specific aspects of seabird research, conservation awareness and including identification guides for use aboard.
On the third day, we took everyone to sea for some practical experience identifying some common seabird species onboard a fishing boat from Puerto Quequén. After a few hours steaming we were able to put into practice some of the concepts we had taught over the previous days and the observers had the chance to identify over ten species of albatross, petrels
, shearwaters, penguins, skuas and gulls.
The experience was marvellous and resulted in a great benefit for all concerned, students and teachers alike!!
Another action-packed Save Our Seabirds Festival was held this year at the Iziko Museum in Cape Town. The highlights of the week included three evening lectures, two birding outings to Robben Island and a photographic competition.
The week kicked off with an opening address by a staff member from the Department of Environmental Affairs (DEA), followed a very interesting talk titled, “The good, bad and the ugly of seabird conservation by Peter Ryan. Dr Sam Peterson (from WWF-SA) spoke about sustainable fishing and the South African Sustainable Seafood Initiative (consumer awareness programme) in today’s changing environment. The final presentation of the week was given by Steve Kirkman (DEA) on the possibility of seals and seabirds coexisting. All evenings were full to capacity with over 120 people attending! At these evening lectures, Diemersfontein Wine Estate launched their new Diemersfontein “For the Birds” wine, with a portion of sales of this wine from now onwards, being donated directly to BirdLife South Africa’s Save Our Seabirds Fund.
This year’s photograph competition’s theme was not confined to photographs of seabirds but could include any animal of our oceans. We had an overwhelming response and it was an extremely tough job for our judges to pick the top 45 pictures. These were given prime position in the exhibition hall of one of our museums, illuminated by light boxes, displaying their magnificent colour and making the hall come alive! The winner of the competition, Jill Sneesby, won herself the brand knew CANON EOS 7D camera (donated by CANON SA), with her picture of a Gentoo penguin leaping out of the ocean. As the quality of these images was so high, the museum allowed them to be left on display in for 5 weeks!
Last, but definitely not least, we once again were lucky enough to be able to offer 40 people the opportunity to be guided on Robben Island, in search of the elusive Chukkar Partridge (see image by R. Wanless, right) and peacocks! Robben Island is the only place in South Africa where feral populations of these species are found!
The week gave us the opportunity to once again show case the work of BirdLife South Africa and the South African Albatross Task Force!
At this time of year in the southern hemisphere you can enjoy a stroll along the harbour and, in the evening, watch the vessels gently roll in with their ice boxes full of fish as they arrive to the bustling activity of the port.
Over the last week I’ve been dedicating my work to this peasant activity - port visits in the city where I live, Mar del Plata, in the province of Buenos Aires. This work is orientated toward identifying the smallest vessels of the national fleet, the coastal trawlers. By identifying the different techniques and operational factors of the vessels within the fleet we hope to generate a database of vessels that will serve as a useful reference as we develop future estimations of seabird bycatch.
In general, the coastal boats are relatively small; mostly less than 20 metres total length and they catch a variety of species, working with a suite of different fishing gears. They work all year round and never stop, changing the target species according to the season.
I’ve been recording these details and which boats make daily trips, or stay out for three to four days. In order to do so, I head down to the port at around six o’clock in the afternoon, when the vessels are arriving from sea. As they unload their catch I hold short discussions and interviews with the crew about fishing, our campaign to save the albatross and how our work is connected.
Access to the port and loading areas is open to the public thanks to the influence of tourism in Mar del Plata, and the interest generated by all the orange-painted vessels. It is a real post-card moment for many people who visit. My presence also causes significant interest, and I find myself answering lots of questions about our work and our interaction with the fleet.
So far I’ve identified over 90 vessels and have recorded details from the interviews about the capture of not only albatross, but also smaller species of petrel and shearwater. At the moment this aspect is still at an early stage as we need to document the nature of the bycatch first hand through at-sea work. However, these coastal boats are small and available space is really limited. There is hardly enough room for the crew which makes safety a real concern.
Our emerging work with this fleet is of great importance as it permits us to further understand and interact with this fleet and the artisanal fishing community.