United States

**Abstract:**

The Yelkouan Shearwater (Puffinus yelkouan) is a Mediterranean endemism, classified as Vulnerable following its decreasing population trend. Between 27-60% of the 21-36,000 pairs estimated at the global level breed at a single site of ca. 6 sqkm, the island of Tavolara (Italy 40°54&#39;N 09°42&#39;E). GPS tracking of 22 adults (60 tracks) during the 2011-2015 breeding seasons describe a trans-national foraging range which stretches across the NW Mediterranean Sea, between the western coast of Sardinia island, Italy (39°50&#39;N 08°13&#39;E) and the Gulf of Lion, France (43°00&#39;N 03°40&#39;E). Within this wide area, core foraging clusters obtained from tracks during incubation (N=44) and chick-rearing (N=16) overlap areas of primary productivity blooms, which in the Mediterranean typically lie in coastal areas close to river estuaries. In particular, the Gulf of Lion (Rhone river mouth) represents the final destination of all trips during chick-rearing. The Mediterranean sea is featured by a generally low primary production and estuaries represent seasonally-predictable productivity hotspots during boreal spring and summer. Foraging trips entail long-distance flights lasting up to 10 days, and their duration increases during the breeding season (median value during incubation 2.0 days, vs 6.5 days during chick growth), when food requirements are at their maximum and areas rich of food are far from the colony and very localised.

**Authors:**

Marco Zenatello¹, Francesco Pezzo¹, Giulia Cerritelli², Augusto Navone³, Dimitri Giunchi², Giovanna Spano³, Enrica Pollonara², Alessandro Massolo², Anna Gagliardo², Nicola Baccetti¹

¹ISPRA (Italian Institute for Environmental Protection and Research), ²University of Pisa, ³Marine Protected Area Tavolara - Punta Coda Cavallo

3rd World Seabird Conference

The largest colony in the smallest kingdom of the world: the tale of Yelkouan shearwaters from Tavolara island (Italy)

**Abstract:**

The Yelkouan Shearwater (Puffinus yelkouan) is a Mediterranean endemism, classified as Vulnerable following its decreasing population trend. Between 27-60% of the 21-36,000 pairs estimated at the global level breed at a single site of ca. 6 sqkm, the island of Tavolara (Italy 40°54'N 09°42'E). GPS tracking of 22 adults (60 tracks) during the 2011-2015 breeding seasons describe a trans-national foraging range which stretches across the NW Mediterranean Sea, between the western coast of Sardinia island, Italy (39°50'N 08°13'E) and the Gulf of Lion, France (43°00'N 03°40'E). Within this wide area, core foraging clusters obtained from tracks during incubation (N=44) and chick-rearing (N=16) overlap areas of primary productivity blooms, which in the Mediterranean typically lie in coastal areas close to river estuaries. In particular, the Gulf of Lion (Rhone river mouth) represents the final destination of all trips during chick-rearing. The Mediterranean sea is featured by a generally low primary production and estuaries represent seasonally-predictable productivity hotspots during boreal spring and summer. Foraging trips entail long-distance flights lasting up to 10 days, and their duration increases during the breeding season (median value during incubation 2.0 days, vs 6.5 days during chick growth), when food requirements are at their maximum and areas rich of food are far from the colony and very localised.

**Authors:**

Marco Zenatello¹, Francesco Pezzo¹, Giulia Cerritelli², Augusto Navone³, Dimitri Giunchi², Giovanna Spano³, Enrica Pollonara², Alessandro Massolo², Anna Gagliardo², Nicola Baccetti¹

¹ISPRA (Italian Institute for Environmental Protection and Research), ²University of Pisa, ³Marine Protected Area Tavolara - Punta Coda Cavallo

technical paper

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:**

Many animal species show sexually divergent foraging behaviours reflecting different physiological constraints or energetic needs. However, the mechanism behind these observed differences is often poorly understood. Here we investigate fine-scale sex-based differences in foraging behaviour of a sexually monomorphic seabird, the northern gannet using a bioenergetics approach. We tracked 12 gannets using a combination of GPS and accelerometer loggers during the breeding season. Measures of dynamic body acceleration were converted to kilojoules to quantify foraging costs in relation to energy intake from diet. Male gannets were lighter than female gannets, and dive rate was lower in males than females. However, sex differences in dive energetics were relatively minor, male plunge dives were energetically cheaper, while male pursuit dives were energetically more expensive than for females. Stable isotope analysis of blood samples was used to model individuals' diet through Bayesian mixing models, which informed average kilojoule intake values from successful prey capture attempts. We then calculated minimum prey capture success rates to sustain movement, maintain body condition, and provision chicks during a foraging trip. While there were no obvious differences in calorific intake between the sexes, males had higher minimum prey capture success rates and due to the lower number of dives performed, must be 14% more successful than females when engaging in prey capture attempts. Our study suggests that sex-specific differences in foraging can be mediated by differences in prey capture, and that these differences may be more nuanced and widespread than previously thought.

**Authors:**

Ashley Bennison¹, Joan Giménez¹, John Quinn¹, Mark Jessopp¹

¹University College Cork

Sex, prey capture rates, and the bioenergetics of foraging in the northern gannet

**Abstract:**

The massive concentration of seabirds in small terrestrial habitats for breeding can encompass a pulsed, predictable, and high-quality feeding resource for terrestrial predators. The Striated caracara (Phalcoboenus australis) is a globally Near Threatened raptor specialized in the exploitation of seabird colonies during breeding season. In a 4 Km2 bay in Isla de los Estados, Argentina, near 300,000 seabirds breed between September and late March. In order to understand the level of dietary dependence on local marine resources, we examined breeding behavior and intra-specific variation in the trophic niche of caracaras during breeding season using stable isotope and pellet analysis. All nests of caracaras were associated mainly with the rockhopper penguin (Eudyptes chrysocome) colony on the island. Isotopic niche varied with, age, breeding status, and, year, but in all cases over 75% of their diet came from seabird colonies. Pellet analysis showed a similar pattern, with down feathers, feathers and eggs of penguins present in over 80% of the samples. Mercury (Hg) analysis in feathers suggest high levels of contamination, with adult feathers averaging over 26 mg/kg. Rockhopper penguins have been reported to present high levels of Hg in the area, thus this high dependence of caracaras on penguin prey represents a higher vulnerability for this caracara population. Overall, seabirds, and especially rockhopper penguins, appears to modulate trophic ecology and mercury exposure of its main terrestrial predator.

**Authors:**

Ulises Balza¹, Nicolás Lois², Klemens Pütz³, Michael Polito⁴, Rebecka Brasso⁵, Andrea Raya-Rey¹

¹Centro Austral de Investigaciones Científicas (CADIC-CONICET), ²Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA-CONICET), ³Antarctic Research Trust, ⁴Louisiana State University, ⁵Weber State University

Seabird's pulsed abundance modulates breeding season ecology and mercury exposure of a highly associated bird of prey

**Abstract:**

The theory of competitive exclusion predicts that, when the resources are limited, species with similar trophic requirements can only coexist if there are differences in some dimensions of their ecological niche. The estuary of Ría Deseado, in Argentina, is one of the few places in the world where four species of cormorants coexist: the Red-legged cormorant (Poikilocarbo gaimardi), the Rock shag (Leucocarbo magellanicus), the Imperial shag (L. atriceps) and the Neotropic cormorant (Nannopterum brasiliensis). To determine possible interspecific differences in one or more of their niche dimensions related to the use of resources during the breeding season, we studied the dietary (pellets), isotopic (stable isotope), spatial (foraging areas) and temporal (breeding calendar) dimensions of the trophic niche of these four sympatric species, between 2009 and 2013. We found that the Red-legged cormorant was located at a low trophic level; he fed almost exclusively on pelagic prey and segregated its core feeding areas from other species. The Rock shag was located at a high trophic level and presented the most benthic and diverse diet, including several invertebrate taxa. The Neotropic cormorant was situated at a similar trophic level as the Rock shag, with which it overlapped its isotopic niche, as well as its core feeding areas. The Neotropic cormorant fed only on fishes. Finally, the Imperial cormorant segregated isotopically, spatially and temporarily from the other species. Its trophic level was situated in between the Red-legged and the Rock-Neotropic group. Regarding the breeding calendar, the Neotropic cormorant was the most asynchronous species, and the one that presented the latest chick-rearing peak. In general, the four species showed a partition of the use of their resources despite occupying a rather restricted geographical space. The observed differences possibly act by reducing competition during the reproductive period when birds are restricted to exploit resources within a limited area. The multidimensional approach to study the use of the trophic resources of these four species allowed us to find that the degree of interspecific segregation varied according to the dimension examined.

**Authors:**

Annick Morgenthaler¹, Ana Millones¹, Patricia Gandini², Esteban Frere²

¹Centro de Investigaciones de Puerto Deseado, Universidad Nacional de la Patagonia Austral, ²Centro de Investigaciones de Puerto Deseado, Universidad Nacional de la Patagonia Austral, and CONIC

Dividing the pie: the use of trophic resource by four sympatric species of cormorants in a saltwater estuary from Southern Patagonia

**Abstract:**

Although our understanding of the foraging ecology of adult seabirds has been greatly enhanced by the development of biochemical analyses as well as the miniaturization of tracking devices, there remains limited information on important foraging areas during the non-breeding season. Even less is known about the spatial and dietary overlap of seabird species during the non-breeding season, which could lead to interspecific competition during low productivity winter conditions. We aimed to quantify spatial niche overlap among Common Murres (Uria aalge), Razorbills (Alca torda), and Atlantic Puffins (Fratercula arctica) outside the breeding season. Using data from geolocators deployed on puffins, razorbills, and murres during July 2019 and 2020 in coastal Newfoundland and retrieved the following summers, we developed kernel density maps throughout the non-breeding period in both years. Seasonal utilization distributions of each alcid species indicate low spatial overlap during most months in the non-breeding period, with exceptions in early fall, and for some puffins that overlapped with razorbills along the North American coast. Our next steps will combine these spatial analyses with exploration of isotopic niche overlap, using bulk and compound-specific stable isotope analysis of feathers grown during different parts of the non-breeding season. Elucidating the overwintering overlap along spatial and isotopic niche axes for these three alcid species increases our understanding of potential interspecific interactions during a formerly understudied phase of the annual cycle, thereby enhancing our ability to predict seabird responses to varying environmental conditions.

**Authors:**

Emily Runnells¹, Gail Davoren¹

¹University of Manitoba

Non-breeding niche overlap of three North Atlantic alcid species

**Abstract:**

Breeding at the right place is essential for seabirds to ensure a compromise between access to the resources, being safe from predation and deal with local weather. A challenge in ecology is to predict the demographic responses of populations in a context of climate change. Understanding demographic differences between multiple populations or colonies is central to determining some of the underlying mechanisms that drive these responses. Variability in population responses occur at large spatial scales, and studies have already shown different demographic strategies between several sites, but this understanding remains fragmentary and insufficient. However, on small spatial scales, analyzes between several nearby colonies have rarely been conducted, neglecting direct weather effects of other local effects. Here, we estimated the demographic parameters between several seabird colonies at different spatial scales and then assessed the differences in the demographic responses of these populations to environmental variations. We used individual monitoring data from three nearby colonies of snow petrel to investigate small-scale differences. To investigate the large-scale differences, we used two distant populations of closely related marine predators with similar ecological requirements, the south polar skua and the brown skua. Using capture-mark-recapture models, we estimated the survival and reproductive performance of each species at different sites. Our results show that breeding performance can vary both on large and small spatial scales. In addition, for snow petrels, local weather conditions may affect colonies differently resulting in different demographic responses. Very few studies have taken into account spatial heterogeneity when studying seabird population responses and generally make inferences from a single study site. To draw general conclusions about these responses, it is necessary to study in more detail, on several sites, a greater number of species in marine ecosystems.

**Authors:**

Christophe Sauser¹, Nathan Pacoureau², Karine Delord¹, Christophe Barbraud¹

¹CNRS - Centre d'étude biologique de Chizé, ²Simon Fraser University

The role of multi-colony studies in understanding seabird demography

**Abstract:**

Demographic rates such as recruitment and survival probability can vary considerably among populations of the same species, possibly due to spatially auto-correlated environmental processes. Breeding populations and foraging ranges are spatially segregated in colonial seabirds, making them ideal to study spatial patterns in demographic rates and their effects on local population dynamics. We investigated differences in age-dependent survival rates of Herring Gulls (Larus argentatus) breeding along the Dutch North Sea coast and we explored variation in survival among colonies in the context of their spatial distribution in the Netherlands. Between 1986 and 1988, per year approximately 100 nearly fledged individuals in 12-14 colonies received a unique colour ring, and birds have been resighted up until 2019 when at least one bird is known to be alive. We assessed whether survival until recruitment or until ten years old (their expected lifespan) explained variation in population trajectories of each colony. Juvenile and adult survival showed a strong, but different, north-to-south gradient in survival probability, while the spatial pattern of immature survival was less distinct. Recruitment nor the proportion of 10-year-old adults alive predicted whether a colony collapsed, declined, remained stable or increased. The distinct spatial pattern in survival suggests variation in regional food availability, which do not seem to drive local population dynamics. The absence of a link between survival and colony trajectories implies that connectivity between populations plays an important role affecting population dynamics.

**Authors:**

Rosemarie Kentie¹, Judy Shamoun-Baranes², Arie Spaans³, Kees Camphuysen⁴

¹University of Amsterdam & Royal Netherlands Institute for Sea Research NIOZ, ²University of Amsterdam, ³retired from Wageningen Environmental Research ? WUR, ⁴Royal Netherlands Institute for Sea Research NIOZ

Age-dependent survival of Herring Gulls across 14 contrasting colonies

**Abstract:**

In colonial seabirds, ecological divergence may occur in the absence of physical barriers, driven by the isolation of populations due to distance, or the adaptation to local environment. In migratory seabirds, the geographic segregation among breeding populations can persist year round (i.e., strong migratory connectivity) when populations breeding separately do not mix outside the breeding area either, segregating in different non-breeding grounds. This migratory connectivity can exacerbate the isolation among populations, and thus influence the genetic structure among them. We have studied the non-breeding ecological niche and the migratory connectivity among 34 colonies of three Calonectris taxa, Scopoli's (C. diomedea), Cory's (C. borealis), and Cape Verde (C. edwardsii) shearwaters (805 breeding adults in total). To understand at what spatial scale migratory connectivity and preferences in non-breeding environment operate, and whether they are favouring ecological divergence among populations, we calculated migratory connectivity and non-breeding environmental niche at a colony, population and taxa level. To define populations, we grouped colonies in distance-based groups formed by the colonies that fell within buffers of increasing radius. At a taxa level, we found ecological segregation among the three taxa, with a clear spatial segregation between Scopoli's shearwaters and the other two taxa. At a colony level, we found low migratory connectivity among colonies of both Cory's and Scopoli's shearwaters, indicating high degree of individual mixing in the non-breeding areas. However, when we grouped the colonies in distance-based populations, the migratory connectivity increased, and differing environmental preferences appeared among populations, indicating the presence of some spatial structure at a population level. Our results agree with an ecological and evolutionary segregation among Cory's, Scopoli's and Cape Verde shearwaters, highlighting the role of migratory connectivity in the process of genetic divergence of populations across a landscape without physical barriers.

**Authors:**

Virginia Morera-Pujol¹, Paulo Catry², Maria Magalhães³, Clara Péron⁴, José Manuel Reyes-González⁵, José Pedro Granadeiro⁶, Teresa Militão⁵, Maria Dias⁷, Daniel Oro⁸, Giacomo Dell'Omo⁹, Martina Müller¹⁰, Vítor Paiva¹¹, Benjamin Metzger¹², Verónica Neves¹³, Joan Navarro¹⁴, Georgios Karris¹⁵, Stavros Xirouchakis¹⁶, Jacopo Cecere¹⁷, Ángel Sallent¹⁸, Manuela Forero¹⁹, Fernanda de Felipe¹, Zuzana Zajková¹, Marta Cruz-Flores¹, David Grémillet²⁰, Jacob González-Solís¹, Raül Ramos¹

¹Universitat de Barcelona, ²ISPA-Instituto Universitário, ³Regional Secretariat for the Sea, Science and Technology, Regional Directorate for Sea Affairs (DRAM, ⁴Université de Montpellier, ⁵nstitut de Recerca de la Biodiversitat (IRBio) and Departament de Biologia Evolutiva, Ecologia i Ciè, ⁶Universidade de Lisboa, ⁷BirdLife International, ⁸IMEDEA (CSIC-UIB) and Centre d'Estudis Avançats de Blanes (CSIC), ⁹Ornis Italica, ¹⁰Nagoya University, ¹¹University of Coimbra, ¹²BirdLife Malta, ¹³Universidade das Azores, ¹⁴Institut de Ciències del Mar, CSIC, ¹⁵Ionian University, ¹⁶University of Crete & Natural History Museum of Crete, ¹⁷Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA), ¹⁸University of Murcia, ¹⁹Estación Biológica de Doñana CSIC, ²⁰University of Cape Town

Speciation and ecological divergence in three closely related shearwater taxa: insights from migratory connectivity and non-breeding habitat

**Abstract:**

The grey-faced petrel Pterodroma gouldi is endemic to the North Island of New Zealand. Although not threatened overall, this species is only abundant at a few sites, and in very small declining populations at most other sites. Causes for decline can be varied, but are generally introduced mammal predation or changes in oceanographic conditions. Independently of predation, marked variation in chick development and breeding success has been observed among colonies, particularly between those located along the East and the West coasts, and among years. We investigated the role played by adult foraging strategy, oceanographic conditions and predation in the variation of these breeding performances. East coast colonies were monitored for breeding performances during the 2011, 2012 and 2015 breeding seasons. Both East and West coast colonies were monitored for breeding success and chick development as well as for adult foraging strategy during the 2013 and 2014 breeding seasons. We deployed GPS devices to identify foraging areas, determined the frequency of chick feeding and adult foraging trip duration, and evaluated trophic position by stable isotope analyses of adult and chick diet and their prey. We found that grey-faced petrels breeding on the East coast tended to travel further from their breeding ground to feed, foraging for a longer period and thus fed their chicks less frequently. Stable isotope analyses revealed different δ15N and δ13C values between East and West coast breeders suggesting the use of different trophic levels and foraging habitats during chick rearing. Oceanographic conditions affected chick growth while predation by introduced mammals strongly impacted breeding success. An understanding of seabird diet and foraging strategy informs their conservation and management, as monitoring seabird trophic niche dimensions, foraging areas and reproductive parameters can reveal causes for population declines.

**Authors:**

Karen Bourgeois¹, Jemma Welch², Sylvain Dromzée³, Rob Dunn⁴, Megan Friesen⁵, Matt Rayner⁶, Graeme Taylor², James Russell⁴

¹Expertise Conservation des Oiseaux Marins et de la Biodiverité Insulaire (ECOMBI), ²Department of Conservation, ³Office Français de la Biodiversité, ⁴University of Auckland, ⁵Saint Martin's University, ⁶Auckland Museum

Spatio-temporal variation in chick growth and breeding success in the grey-faced petrel Pterodroma gouldi

**Abstract:**

Disentangling the roles of different intrinsic and environmental factors in driving seabird population changes in a large-scale perspective is highly important in a rapidly changing world. For seabirds such studies are rare. Finding the main drivers behind adult survival and population change, are important since many seabird species are threatened. Unravelling the role of different factors of climate change, such as ocean warming and associated shifts in prey availability, and extreme weather and storms events which are known to cause mass mortality, and thus represent an additional and potentially growing threat given the predicted increase in the frequency of such events are also important. Yet, there may be remarkable variation among populations in terms of how climate is having an effect due to spatio-temporal variation in the birds' distribution as well as the physical effects of climate change. As a consequence, the demographic traits that drive population changes may vary among populations. In this study we combine demographic (productivity and survival rates) and population trend data from nine North-Atlantic puffin colonies from the UK, Iceland and Norway with parallel data on environmental conditions in order to identify key drivers of population changes. Information from the seabird tracking programme SEATRACK was used to identify key non-breeding areas for each of the study colonies, enabling environmental covariates likely to be associated with overwinter survival (storm tracks, SST, large-scale climate indices and oceanographic factors) to be extracted for each population. We used multi-state CMR analysis, LTRE analysis and population modelling, to reveal some key ecological processes that underpin the relationship between puffins and their environment. Understanding these relationships is crucial when assessing how and where management actions could be put in place, and should be maintained as an integrated part of our knowledge base to support the future management of threatened seabirds.

**Authors:**

Tone Kristin Reiertsen¹

¹Norwegian Institute for Nature Research

The impact of demographic and environmental drivers on the Atlantic puffin populations: a multi-colony perspective

**Abstract:**

The way in which demographic rates fluctuate synchronously across spatially disjunct populations can have important consequences for the long-term persistence of metapopulations and can also be used to infer drivers of population dynamics. Here, we examined spatial patterns of synchrony in the breeding success of black-legged kittiwakes Rissa tridactyla in the UK, making use of time series from multiple colonies spanning three decades. We found that the strength of breeding success synchrony declined with distance between colonies, but also that some groups of colonies formed spatially coherent clusters in which breeding success fluctuated in unison. Furthermore, the spatial patterns of synchrony we identified aligned well with the spatial structure of the kittiwake's main prey in this region - the lesser sandeel Ammodytes marinus. This thus suggests that the spatially independent and disparate dynamics of sandeel subpopulations filter up to the level of kittiwakes, with important consequences for kittiwake demography. The study shows that examining spatial patterns of multi-colony synchrony in demographic rates can provide useful information for identifying environmental drivers as well as the spatial scale over which they are acting, improving our understanding of dynamics both at the scale of individual and multiple colonies.

**Authors:**

Agnes Olin¹, Neil Banas², Peter Wright³, Michael Heath², Ruedi Nager⁴

¹Stockholm University, ²University of Strathclyde, ³Marine Scotland Science, ⁴University of Glasgow

The largest colony in the smallest kingdom of the world: the tale of Yelkouan shearwaters from Tavolara island (Italy)

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The largest colony in the smallest kingdom of the world: the tale of Yelkouan shearwaters from Tavolara island (Italy)

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Sex, prey capture rates, and the bioenergetics of foraging in the northern gannet

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