United States

**Abstract:**

Neotropical cormorants (Phalacrocorax brasilianus) are common seabirds along the Peruvian coast. They frequently perch in urban areas (trees, harbors, poles, etc.), causing potential aesthetic and public health problems due to the dropping of feces on infraestructure and people. Large number of these birds use lighting poles to rest on a narrow median in a 12.5 km coastal highway in Lima, Peru. We hipothesized that the distribution of the cormorants in this highway is not random, but it may be associated with abiotic features of the coastline that may favor prey accesibility. Biweekly counts of cormorants per lighting pole between July 2018 and July 2019 revealed that during the study period the total number varied between 15 to 430 birds, and that only 16% of the total number of posts (N = 651) were occupied. A large amount of cormorants were present in the posts at 1000 h and 1400 h, matching the prefered timing of foraging between mid-morning and mid-afternoon. Cormorants were clustered in four recurrent main groups along the highway, i.e., the spatial distribution was no-random. An AIC model selection approach determined that the presence of the cormorants in these sites were strongly related to a closer distance to the coastline and the isobath 7 m, and to the presence of breakwaters. No relation was found with the turbidity of the sea (measured &lt; 1,300 m from the shorline). These findings suggest that neotropical cormorants may select these sites for a better sighting or detection of prey. Any management for relocation of cormorants from the lighting poles in this highway must take into consideration mainly the distance of perching sites to the shoreline and the occurrence of breakwaters.

**Authors:**

Sebastián Lozano¹, Carlos Zavalaga¹

¹Universidad Científica del Sur

3rd World Seabird Conference

Non-random spatial distribution of the neotropical cormorant (phalacrocorax brasilianus) in an urban area in Peru

Welcome Seabirders!  

Welcome to Virtual World Seabird Conference 3 - vWSC3! Whether you are in your office or lab, at home, in a coffee shop or bar poaching some wifi, or at a remote field site or research vessel – we are very excited to welcome you to the third ever World Seabird Conference. 

We would like to thank ALL of you for being so patient as WSC3 was scheduled, postponed, rescheduled, revised to virtual, and scheduled again. Throughout all those iterations there was one message that remained perfectly clear – seabirders were eager to meet and share their science. If we could not meet in person then virtual it would have to be, but a 3rd WSC was something everyone wanted. That support and commitment helped the WSU Board of Directors and Member Societies sort through all of the challenges they faced to plan and hold this conference. 

The list of those that need to be thanked is long and, while we plan on recognizing many during the live closing plenary, it is important to do so here in writing as well. 

The Australasian Seabird Group was our Local Host for our plan to meet in Hobart, Tasmania. They invested substantial time and effort to find venues and plan events that we unfortunately were not able to visit. Nonetheless we appreciate their work on behalf of WSC3 and encourage all of you to thank them when you see their members in Gathertown or elsewhere during our virtual meeting. Their willingness to host created the initial excitement for WSC3 and without that our vWSC would not have been possible.

We also wish to thank the Science Program Committee, the Virtual Committee, and the Early Career Scientist Committee for their hard work planning the logistics, events, and schedule for vWSC3. These committees also had to deal with changing parameters and short timelines that made what is always a challenging task even more challenging. The Travel Awards Committee also invested time and effort in developing procedures for awarding travel funds that ultimately would not be implemented. 

Our ability to shift from an in-person to a virtual meeting, and to do so in a way that would be financially feasible, was due to the effective efforts of The International Fundraising Committee and to our financial sponsors. The IFC raised funds to support WSC3 and then, through the good relationships they built with sponsors, ensured we could re-envision how those funds could be used to support a virtual conference that would be affordable and high-quality.

We all owe the WSU Board of Directors and the Representatives of the Member Societies a great deal of thanks. They are the ones who manage the WSU and, for the past 18 months, have had to have a series of challenging meetings and conversations, have had to make a series of difficult choices, have had to do all of that while considering the short- and long-term health of WSU and the World Seabird Conferences, and did this while also managing their own challenges at their day jobs. We are grateful for their diligence, patience, foresight, and throughout all of the meetings, their collegiality. Also – a 6-year term is quite a commitment!

There would not be a WSC3 without a successful WSC1 and WSC2. Thanks go to the Pacific Seabird Group for their support of WSC1 in Victoria, Canada, and to the African Seabird Group for their support of WSC2 in Cape Town, South Africa. In each of these endeavors and for our current conference we were fortunate to work with a dependable and trustworthy partner in Podium Conferences. Michelle Smith and Marischal de Armond have become valued members of our team and have not only helped us plan conferences but have assisted and advised the WSU Chairs and Board on issues above and beyond conference planning. 

As we embark on our vWSC3 week we extend to all of you our thanks for showing up, for being patient, and most importantly for the work you do with seabirds. We are all part of a unique, global community that shares an interest, a fascination, and a passion for birds that make a living in our world’s oceans. We have advanced the science, conservation, and management of seabirds as well the ecosystems they inhabit. We are consistently impressed and motivated by the work you do. 

The WSU formed in 2010 because we saw the need for a global organization to address challenges at a global level. Over the past 11 years WSU has grown, adapted, and evolved to become the community that this week is making vWSC3 a reality. Enjoy the week, appreciate and support the friends and colleagues you have made in the community, and if you see us in a virtual hallway please stop and say hello! 

Thank you for the opportunity to serve all of you and the WSU over the past few years,

Nicholas Carlile, Interim Chair, WSU<br>
Patrick Jodice, 2nd Chair of the WSU<br><br>

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Join us for four days of science, networking and virtual engagement with delegates from around the world!

**Abstract:**

Neotropical cormorants (Phalacrocorax brasilianus) are common seabirds along the Peruvian coast. They frequently perch in urban areas (trees, harbors, poles, etc.), causing potential aesthetic and public health problems due to the dropping of feces on infraestructure and people. Large number of these birds use lighting poles to rest on a narrow median in a 12.5 km coastal highway in Lima, Peru. We hipothesized that the distribution of the cormorants in this highway is not random, but it may be associated with abiotic features of the coastline that may favor prey accesibility. Biweekly counts of cormorants per lighting pole between July 2018 and July 2019 revealed that during the study period the total number varied between 15 to 430 birds, and that only 16% of the total number of posts (N = 651) were occupied. A large amount of cormorants were present in the posts at 1000 h and 1400 h, matching the prefered timing of foraging between mid-morning and mid-afternoon. Cormorants were clustered in four recurrent main groups along the highway, i.e., the spatial distribution was no-random. An AIC model selection approach determined that the presence of the cormorants in these sites were strongly related to a closer distance to the coastline and the isobath 7 m, and to the presence of breakwaters. No relation was found with the turbidity of the sea (measured < 1,300 m from the shorline). These findings suggest that neotropical cormorants may select these sites for a better sighting or detection of prey. Any management for relocation of cormorants from the lighting poles in this highway must take into consideration mainly the distance of perching sites to the shoreline and the occurrence of breakwaters.

**Authors:**

Sebastián Lozano¹, Carlos Zavalaga¹

¹Universidad Científica del Sur

technical paper

**Abstract:**

Populations at range edges may be unique genetically and be the first to show impacts of climate change. Penguin Island, Western Australia, is home to a genetically distinct population of little penguins (Eudyptula minor) at the extreme north-western limit of the species range. Recent studies suggest that this population is likely to be negatively impacted by anticipated changes in marine climate and prey availability yet correspondingly little is known regarding climate change impacts on nesting habitat. Conservation interventions at the population scale may rely on the intensive management and restoration of terrestrial habitat to facilitate population resilience and buffer the adverse effects of climate change. Thus, among the critical elements of successful conservation planning for long term species persistence is a comprehensive understanding of habitat use, microhabitat conditions and climate change impacts at range edges. We characterised little penguin nesting habitat and quantified relationships between nest attributes, microclimate and nest use. Subsequently, we implemented a manipulative study testing two artificial nest designs and four shading treatments to determine how to most effectively emulate the microclimate of natural cavities. Artificial nest boxes experienced consistently higher daily maximum temperature (~2 ˚C) and maintained temperatures above little penguins' upper thermoneutral limits for around one hour longer than natural nests. Ambient weather conditions and fine scale biotic and abiotic nest characteristics influenced the maximum daily nest temperature and hours of exposure to upper thermoneutral limits. Experimental manipulation of boxes and shading revealed nest design and shading methods were effective at reducing nest temperature. Compared to exposed boxes, artificial shading and shading vegetation had the greatest buffering effect, significantly lowering maximum nest temperature by around 4.5 ˚C and reducing the time of exposure to upper thermoneutral limits by one hour. Further, shaded treatments had thermal profiles either comparable to, or up to 2 ˚C cooler than, natural nests. This study provides insight into how predicted changes in climate may impact species living at their thermal limit and highlights the conservation implications of informed habitat management and artificial nest design. Our results inform land-based efforts to buffer climate change effects on range-edge populations.

**Authors:**

Erin Clitheroe¹, Joe Fontaine¹, Belinda Cannell²

¹Murdoch University, ²The University of Western Australia

Helping or hindering? Evaluating artificial nests as a climate adaptation tool in a range edge population

**Abstract:**

The southern tip of Africa is experiencing marked changes in land and sea temperatures, wind patterns and ocean currents, with resulting impacts on marine species and ecosystems. One of the most affected species, the endangered African penguin (<I>Spheniscus demersus</I>), has declined dramatically in recent decades, but climate change is rarely acknowledged as a key contributor to this population trajectory. However, the critical threat to this species, reduced food abundance, is exacerbated by climate change driven reduced prey abundance and distribution shifts. Extreme weather, leading to hyperthermia and abandonment of penguin chicks by parents, habitat loss due to storm surges and heavy rain, and disease outbreaks have all been exacerbated by climate change. While some conservation measures promoting climate change adaptation have been implemented, others remain in the planning phase or are purely contemplative "penguins in the sky". We report on current and planned management interventions, such as rescue of penguins, in particular abandoned eggs and chicks, provisioning and rehabilitation of safe nesting habitat as well as improved habitat protection from erosion and flooding, improving fish availability (through improved fisheries management and declaration of MPAs), establishment of new colonies, disease surveillance and prevention, and parasite studies. Several such interventions are already in their initial phases, creating species' resilience and raising awareness for climate change among government and resource managers. "Penguin in the sky" interventions, i.e. those that might seem far-fetched at present, may however become necessities under rapidly escalating climate change impacts. These include increasing the elevation of breeding islands, creating new islands and securing land upslope of mainland populations for conservation, complete closure of fisheries -- and others that we haven't yet thought of.

**Authors:**

Katta Ludynia¹, Nicola van Wilgen², Wendy Foden², Alison Kock², Darrell Abernethy³, Barbara Barham⁴, Peter Barham⁵, Marcela Espinaze⁶, Christina Hagen⁷, Azwianewi Makhado⁸, Trudi Malan⁹, Sonja Matthee⁶, Alistair McInnes⁷, Arne Purves¹⁰, Laura Roberts¹¹, Kevin Shaw¹², Richard Sherley¹³, Albert Snyman¹⁴, Lauren Waller¹⁵

¹SANCCOB/University of Cape Town, ²SANParks, ³University of Pretoria, ⁴Penguin Datasystems, ⁵University of Bristol, ⁶University of Stellenbosch, ⁷BirdLife South Africa, ⁸Department of Environment, Forestry and Fisheries, ⁹Dyer Island Conservation Trust, ¹⁰City of Cape Town, ¹¹Western Cape Government, ¹²CapeNature, ¹³University of Exeter, ¹⁴SANCCOB, ¹⁵SANCCOB/UWC

Current, planned and "Penguins in the sky" - Management interventions for the Endangered African penguin in face of Climate Change

**Abstract:**

The annual customary harvest of titi (Sooty Shearwaters, Ardenna grisea) is a culturally defining wildlife harvest that is of fundamental importance to identity, mahinga kai (food provisioning), transmission of mātauranga (knowledge and wisdom) and the economy of Rakiura Maori. The harvest and Rakiura Titi Islands are managed by Rakiura Maori using tikanga (customary protocols) and matauranga Maori. These cultural guidelines and knowledge are embedded within bylaws and management documents, highlighting the importance of indigenous frameworks for managing seabird populations and habitat. A 14-year research partnership between Rakiura Maori and the University of Otago, founded in matauranga Maori, Rakiura tikanga and science began in 1994. At the time collaborative research partnerships between Maori and university were unique, but none-the-less Rakiura Maori recognised the need to ensure the sustainability of titi harvesting. The research tracked titi breeding density, harvest intensity, bycatch, population changes, measures of survival, reproduction and migration. These parameters were used to build computer simulations of past and future populations under different harvest intensities and climate scenarios. The research highlighted three main threats to sustaining customary harvesting are: climate change, the predation on titi by introduced weka (a native rail, Gallirallus australis), and potential increases in harvest intensity. The model highlighted that the biggest and quickest gain for sustainability would be the removal of introduced weka from birded areas. Weka were introduced to these islands, however management of this species is complicated because of their taonga (treasured species) status and legislative protection mechanisms. Management of weka and harvest intensity requires adaptation of Rakiura Maori management frameworks. The ability to adapt management responses is already demonstrated within this community. Adaptive initiatives include conservation projects, succession planning and development of an application to empower harvesting families to model their harvest management decisions on their manu (birding area).

**Authors:**

Jane Kitson¹, Corey Bragg¹, Phil Lyver²

¹Rakiura Titi Islands Administering Body, ²Landcare Research

Sustaining seabirds and culture: Rakiura Maori management of titi (Sooty Shearwaters) in New Zealand.

**Abstract:**

The White-Tailed-Tropicbird (Phaethon lepturus Daudin, 1802) shows a complex life cycle that uses small areas of aggregation for breeding, for example, on remote South Atlantic islands. Long-term surveys focusing in microscale patterns on breeding colonies can provide specific answers about the behavioral ecology of the species. Thus, we focused on studying the occupation and spatial dynamics of P. lepturus. Monthly, from November 2018 to November 2019, White-Tailed-Tropicbirds were monitored by active search on the Chapeu Islet (25M, 564307.35 m E, 9572126.83 m S; 5886.96 m², elevation 9 m a.s.l., Aw Köppen-Geiger CC, limestone pinnacles geological formation), in Fernando de Noronha Archipelago, Brazil. When an active nest was found, we labeled and geo-referenced the site and marked the specimens with CEMAVE bands. We standardized a 23x25 m² grid over the study area and, from the Morisita Index (MI), it was obtained the spatial distribution and density values per month, which was related to the number of active individuals by simple linear regression (R v.3.6.1. software). 434 individuals with local breeding activity were identified during the studied time, 7.8% (n=34) of local fidelity and, of these, 47.0% (n=16) of nest fidelity, with mostly 7-8 months (n=13) time interval to return back to the islet. In all months, happened an aggregate distribution pattern (MI=3.34±0.72; p<0.05) and an inverse relationship between aggregation and the number of active individuals (F=11.29; p<0.05). By comparing natural history data of P. lepturus with other colonies can provide broader understanding of their population dynamics. The singularity of locations as Chapeu Islet provides specific resources to part of those seabirds species life cycle, connecting individuals that use a wider territorial scale.

**Authors:**

Lucas Santos¹, Ricardo Krul², Hellen Rocha¹, Patricia Serafini¹

¹Chico Mendes Institute of Biodiversity Conservation, ²Brazilian Institute for Conservation Medicine (Tríade)

Microscale occupation and nesting activity of the white-tailed tropicbirds in a south atlantic islet

**Abstract:**

Habitat partitioning, wherein species that occupy the same geographic areas select different locations or resources, is considered key to the coexistence of closely related sympatric species. However, partitioning can be difficult to observe in natural settings due to the complexity of measuring niche breadth across relevant environmental features. Sea ducks, which overlap extensively throughout the annual cycle and utilize similar marine areas during non-breeding, provide an opportunity to apply concepts of habitat partitioning to understand how multiple species can effectively coexist while utilizing shared resources. We collected satellite telemetry data on annual cycle movements of over 500 individual sea ducks of five species (Black Scoter, Surf Scoter, White-winged Scoter, Long-tailed Duck, and Common Eider) from throughout eastern North America and the Great Lakes. To investigate marine habitat partitioning during the non-breeding season, we applied a multivariate habitat selection analysis and compared selectivity values across species, seasons, and environmental characteristics. Our results suggest that niche separation and habitat selectivity are strongest during the post-breeding molt and migration period, when highly productive habitats are spatially limited and individual mobility is restricted. During winter, species show strong preferences for productive nearshore marine habitats, but also overlap extensively in shared habitat areas. Conversely, during spring migration, species show little habitat selectivity or partitioning, suggesting that factors other than environmental covariates are driving habitat use. We discuss the conservation implications of seasonal variation in habitat partitioning and selectivity, and identify key multi-species habitat features used throughout the annual cycle.

**Authors:**

Juliet Lamb¹, Peter Paton¹, Jay Osenkowski², Scott McWilliams¹

¹University of Rhode Island, ²Rhode Island Department of Environmental Management

Seasonal habitat partitioning by sympatric sea ducks in eastern North America

**Abstract:**

The nonbreeding distribution and activity patterns of Yelkouan shearwaters (Puffinus yelkouan) breeding at the most important breeding site, globally, of this endemic Mediterranean species (Tavolara island, Italy 40°54'N 09°42'E) were investigated using combined geolocator-immersion loggers in 2010-2011. Thirteen breeding adults were tagged in early incubation with leg-mounted loggers in March 2010, of which 11 (85%) were retrieved in February-March 2011, at the onset of the following breeding season. There was extensive individual variation in migration patterns: five birds (4 females and one unsexed bird) performed a longitudinal migration to and from the Black Sea, and used stopovers areas in the Strait of Sicily (Italy), Gulf of Gabès (Tunisia) or the Aegean Sea (Greece). Six birds (four females and two males) remained in the Mediterranean basin throughout the nonbreeding period. The ratio of short:long distance migrants was intermediate between populations of Yelkouan shearwaters tracked previously from France and Malta, suggesting an east-west trend in relative use of the Black Sea during the nonbreeding period. Birds spent 133-222 days away from the colony. Immersion data indicate that they were always at sea, and did not return to land in the period between departure from the colony (median 4 July, range 14 May-17 July) and return from migration (median 7 December, range 15 November 2010-8 February 2011). Based on our results and those from French and Maltese colonies, Yelkouan shearwaters show high individual variability in non-breeding distributions and stopover areas, which has implications for their vulnerability to the diverse threats in the Mediterranean, including from fisheries.

**Authors:**

Marco Zenatello¹, Paola Aragno¹, Caitlin Frankish², Giovanna Spano³, Augusto Navone³, Richard Phillips⁴, Nicola Baccetti¹

¹ISPRA (Italian Institute for Environmental Protection and Research), ²University of Cambridge (UK), ³Marine Protected Area Tavolara - Punta Coda Cavallo, ⁴British Antarctic Survey

Nonbreeding distributions and activity patterns of Yelkouan shearwaters from the world s largest colony, Tavolara Island (Italy)

**Abstract:**

Longitudinal studies of basic biological features in seabirds, such as chick growth rate, can provide important information on how parents respond to environmental conditions during the breeding season. Humboldt penguins (HUPE) have adapted to cope with the varying conditions (ENSO) of the dynamic Humboldt Current System, e.g., flexible diet or abandoning the nest if conditions are adverse. Furthermore, studies show that chicks reared under adverse conditions show longer rearing periods reflected in lower growth rates. Our goal was to determine the growth rate of HUPE chicks born and reared until fledgling, during the first breeding season of years 2000 to 2019 in Punta San Juan, Peru. For this, we accessed a long-term database on individual nest checks conducted annually during 2000-2019. We extracted values for three morphometric measures (foot, flipper and bill length) and body mass. Then, we fit measures to non-linear regressions, asymptotic and slope values were extracted to evaluate daily growth rates and the percentage of adult size reached by end of rearing. Due to small sample sizes, only years from 2004 to 2007 were considered for interannual comparisons. The measures that reached adult size at the end of the rearing period were flipper and foot length, while bill length only reached ~80% of adult size. The measure with greatest interannual variation was body mass, followed by bill, flipper and foot length. Significant interannual differences in body mass were only found between years 2005 and 2006 (Wilcoxon, p<0.05). A negative relationship (R=-0.88, p=0.12) was found between mean body mass and SSTA (ONI index) during months of adults post-molt feeding trip. Lack of significance may be affected by small sample sizes. Low correlation during years with weak positive SSTA (2004, 2007) suggest HUPE have strategies to cope with smaller scale environmental changes; however stronger anomalies during onset of breeding may be affecting final chick body mass gain, which is key for post fledging survival.

**Authors:**

Karen Lau-Alarcón¹, Marco Cardeña-Mormontoy¹, Andrés Chavieri-Salazar², Susana Cárdenas-Alayza¹

¹Universidad Peruana Cayetano Heredia, ²Universidad Ricardo Palma

Interannual variation in Humboldt penguin chick growth rate at Punta San Juan, Peru from 2000 and 2019: Preliminary findings

**Abstract:**

Chick vocalization towards parents primarily serves to provide information about its food demands but may be also used for chick recognition. For colonially nesting seabirds the ability to recognize their own offspring is crucial to ensure a breeding success. However, in the case of burrow nesting species, the chick recognition by parents may be less significant, since the own nest can be identified by geographic cues alone. But at some stage of the nesting period chicks get mobile and leave the nest and/or simply fledge, and when still in that time the parental care is to be continued the ability to recognize and care for their own offspring should be important. In the little auk, Alle alle, a burrow-nesting, colonially breeding seabird with a monogamous breeding system, both parents share incubation and care over a single, semi-precocial chick. The male accompanies the chick during fledging and his presence and care is crucial for the young to survive. The aim of this study was to test the inter-individual differences in chick calls at different stages of the nesting period, as well as the recognition of the own chick by the parents. Given the importance of male parent accompanying the chick during the fledging and paternal care at sea, we expected that there are inter-individual differences in the acoustical parameters of the chicks' calls, which allow parent birds to recognize and provide care for their own offspring. Chick calls were recorded in the nests in 2016-2018. Additionally, the cross-fostering experiment was conducted and the parents' feeding performance was monitored. As expected, significant inter-individual differences were revealed in chicks' fledging calls. Also, the begging calls showed a significantly different acoustic features between individuals, both, at the end, and in the mid of the chick rearing period. Surprisingly, parent birds accepted cross-fostered chicks, providing the parental care. Results suggest that there is a potential for chick recognition in the species but apparently recognizing the chick consider geographic cues over the acoustic.

**Authors:**

Dorota Kidawa¹, Mateusz Barcikowski¹, Katarzyna Wojczulanis-Jakubas¹, Dariusz Jakubas¹

¹University of Gdansk

Do inter-individual differences in chick calls assure chick recognition by parents of burrow-nesting colonial seabird, the little auk Alle alle?

**Abstract:**

The Abbott's Booby Papasula abbotti is amongst the most threatened seabirds in the world. The species' only current breeding location is the Australian territory of Christmas Island in the eastern Indian Ocean. There, Abbott's Boobies benefit from conservation actions but insights into its behaviour at sea are crucially missing to implement effective holistic conservation strategies. In particular, the species' migratory behaviour and non-breeding distribution are largely unknown but it is likely that the birds are exposed to various threats during these periods. Using GLS loggers, we studied Abbott's Booby movements during non-breeding. 22 adult birds were tracked between 2007 and 2014, yielding a total of 27 migrations. The birds migrated predominantly easterly off Christmas Island to a relatively restricted area around the Banda Sea, Indonesia. The mean duration of the migration was 121 days (± 21), taking place from 7th December (± 29 days) to 7th April (± 27 days). No significant differences were found in the 50% (core area) and 95% (home range) utilisation distributions (kernel density estimates) between males and females. The results can help develop effective conservation measures: along their migration routes and in their non-breeding foraging habitat Abbott's Boobies are exposed to a number of potentially harmful human activities, in particular fisheries. In addition, oceanographic changes due to global warming could make the crucial foraging area around the Banda Sea less suitable as non-breeding habitat. The spatial restriction of the non-breeding core area makes it a good candidate for an Important Bird Area/Key Biodiversity Area.

**Authors:**

Johannes Chambon¹, Janos Hennicke², Henri Weimerskirch³, Rory Wilson¹, Luca Börger¹

¹Swansea University, ²Bundesamt für Naturschutz, ³French National Centre for Scientific Research

Non-breeding distribution of the endangered Abbott's Booby

**Abstract:**

Bycatch in industrial fisheries is the most pervasive at-sea threat to seabirds globally, for which an array of mitigation measures have been developed. However, seabird interactions with accessory gear, deployed by crew to improve catches or for self-consumption, remains poorly understood. We quantified seabird bycatch in a novel accessory gear deployed by pelagic longline (PLL) fishers off southern Brazil, termed 'buoy hooks' (BH), which consists of short (2-4 m) branchlines clipped straight to bullet buoys, targeting sharks and dolphinfish. This practice was first recorded in 2013, in only two vessels and six trips, by on-board observers voluntarily taken by fishermen. BHs were deployed in 23 (49%) of 47 observed sets, comprising 36,737 and 1,598 hooks for PLL and BH, respectively. Catch rates (number/1000 hooks) of seabirds (BPUE) and target species (CPUE) were compared between gear types. In total, 24 albatrosses or petrels were caught in the PLL (BPUE=0.65) and 28 in BH (BPUE=17.52). Considering only dead birds, BPUE was 0.33 and 6.26 for PLL and BH, respectively. CPUE of target species was 8.66 for PLL (mostly blue shark, tuna and swordfish) and 14.89 for BH (blue shark and dolphinfish). Given the high BPUE in BH, explained by its very shallow fishing depth, even sporadic use across the fleet represents a menace to threatened albatrosses and petrels in this region. Even though the high BPUE recorded was observed in a low number of hooks, we recommend monitoring the use of this accessory gear across the fleet and its potential impacts on seabirds.

**Authors:**

Augusto Silva-Costa¹, Gabriel Canani¹, Tatiana Neves², Dimas Gianuca³

¹Projeto Albatroz/Albatross Task Force Brazil, ²Projeto Albatroz, ³Birdlife International Marine Program

Non-random spatial distribution of the neotropical cormorant (phalacrocorax brasilianus) in an urban area in Peru

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Non-random spatial distribution of the neotropical cormorant (phalacrocorax brasilianus) in an urban area in Peru

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Next from 3rd World Seabird Conference

Helping or hindering? Evaluating artificial nests as a climate adaptation tool in a range edge population

Similar lecture

Microbial ecology of natural and artificial penguin burrows: implications for reproductive success, penguin health and conservation management

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PRESENTATIONS

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COMPANY

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