United States

**Abstract:**

Islands are biodiversity hotspots but are highly sensitive to disturbances, including the introduction of predatory mammals. While there have been considerable advances to the technology used to remove invasive mammals, little is known about the changes island communities experience during recovery. New Zealand - the world&#39;s largest seabird biodiversity hotspot - has cleared mammalian predators from &gt;100 islands over several decades, providing a unique opportunity to quantify island recovery. Here, we examine seabird and vegetative changes at Pokohinu (Burgess) Island, predator-free for almost 30 years, of the Mokohinau Islands. In 2009, we documented seabird distributions, plant diversity, and soil depth across the island and performed smaller surveys in 2014 and 2019. We found an overall 62.5% increase in seabird burrow densities with a strong spatial overlap of species distributions. Diversity of plant species also significantly increased, possibly due to the increased abundance of seed-dispersing birds and the simultaneous expansion of invasive plant species. In addition, we performed burrow and vegetation surveys at other Mokohinau Islands that lack same extent of past human disturbance as Pokohinu, which is a retired lighthouse and farm. Seabird densities between islands were comparable but plant communities lacked many of the invasive species found at Pokohinu. Overall, our results suggest that vegetative cover might not be limiting nesting habitat availability within the Mokohinaus, as seabirds are able to utilize areas dominated by dense vegetation. We emphasize the importance of understanding vegetative succession during recovery periods which may help explain recolonization rates for more specialist species.

**Authors:**

Christy Wails¹, Gaia Dell&#39;Ariccia², Todd Landers², Chris Gaskin³, Dave Towns⁴, Holly Jones¹

¹Northern Illinois Univeristy, ²Auckland Council, ³Northern New Zealand Seabird Trust, ⁴Auckland University of Technology

3rd World Seabird Conference

Keeping up with the tubenoses: Vegetative succession and seabird activity during passive island recovery

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:**

Islands are biodiversity hotspots but are highly sensitive to disturbances, including the introduction of predatory mammals. While there have been considerable advances to the technology used to remove invasive mammals, little is known about the changes island communities experience during recovery. New Zealand - the world's largest seabird biodiversity hotspot - has cleared mammalian predators from >100 islands over several decades, providing a unique opportunity to quantify island recovery. Here, we examine seabird and vegetative changes at Pokohinu (Burgess) Island, predator-free for almost 30 years, of the Mokohinau Islands. In 2009, we documented seabird distributions, plant diversity, and soil depth across the island and performed smaller surveys in 2014 and 2019. We found an overall 62.5% increase in seabird burrow densities with a strong spatial overlap of species distributions. Diversity of plant species also significantly increased, possibly due to the increased abundance of seed-dispersing birds and the simultaneous expansion of invasive plant species. In addition, we performed burrow and vegetation surveys at other Mokohinau Islands that lack same extent of past human disturbance as Pokohinu, which is a retired lighthouse and farm. Seabird densities between islands were comparable but plant communities lacked many of the invasive species found at Pokohinu. Overall, our results suggest that vegetative cover might not be limiting nesting habitat availability within the Mokohinaus, as seabirds are able to utilize areas dominated by dense vegetation. We emphasize the importance of understanding vegetative succession during recovery periods which may help explain recolonization rates for more specialist species.

**Authors:**

Christy Wails¹, Gaia Dell'Ariccia², Todd Landers², Chris Gaskin³, Dave Towns⁴, Holly Jones¹

¹Northern Illinois Univeristy, ²Auckland Council, ³Northern New Zealand Seabird Trust, ⁴Auckland University of Technology

technical paper

**Abstract:**

Seabirds must navigate through wind in search of food, but climate change alters wind regimes. Climate-induced changes in wind have positively impacted wandering albatross (Diomedea exulans), which have evolved to exploit some of the windiest places on earth. However, the effects of changing wind will likely vary according to wing morphology and behaviour, with some species benefitting while others might be at a disadvantage. Northern gannets (Morus bassanus) provide an interesting species in which to study wind effects for a number of reasons. First, in contrast to albatrosses, they have relatively high flight costs and may be adversely affected by strong winds. Second, they plunge-dive from height to catch food, such that strong winds may reduce foraging success. Here we conduct a long-term study (n = 12 years) of the effects of wind on gannet foraging behaviour in the North East Atlantic. We use GPS loggers (n = 335 individuals) to reconstruct foraging trip metrics and ethoinformatics to quantify the amount of time spent performing different behaviours and test how these vary with remotely sensed wind. Overall, we test for the potentially divergent effects of wind on seabird foraging and suggest implications for demographic processes.

**Authors:**

Hannah Meinertzhagen¹, Steve Votier², Matthew Witt¹, Robert Thomas³, Bob Furness⁴, Jason Chapman¹, Beth Clark⁵, Greg Morgan⁶, Lisa Morgan⁶

¹University of Exeter, ²Heriot-Watt University, ³Cardiff University, ⁴MacArthur Green, ⁵BirdLife International, ⁶RSPB

Effects of wind on seabird foraging in the North East Atlantic

**Abstract:**

A significant portion of the global population of Grey-headed Albatrosses (Thalassarche chrysostoma; Endangered) breed on sub-Antarctic Marion Island (46°53′ S 37°44′ E). Although most pairs breed on coastal cliffs, ca 4000 pairs breed on an inland ridge. These birds occasionally crash into the valley below the ridge, with birds either dying on impact or as a result of starvation if they are unable to take off again due to injury or absence of suitable wind conditions. We determined the number of birds affected and their distribution within the valley by counting carcasses and stranded birds in the valley on a regular basis between 2017 and 2019. Of the carcasses recovered, almost half are juveniles presumably killed during their first flight, with 41±23 killed per year (2.4% of chicks fledged each year). On average 45±21 adult carcasses were recovered each year, which represents 0.6% of the annual breeding population along the ridge, making wind-induced collision mortality a significant cause of death for a species that has a natural mortality rate of only ca 4% per year. Wind measurements taken in the area show this region is associated with high turbulence and gustiness. Simulations of wind around the ridge, using computational fluid dynamics (CFD), show that the flow over the area with the highest crash density is characterised by a concentrated down-draft under specific wind conditions. Although albatrosses are efficient at detecting and exploiting wind gradients at sea, operating near ground can be extremely risky, as these birds lack the power needed to respond to strong turbulence and downdrafts that are commonly associated with steep terrain. Crashes represent a source of mortality that is rarely considered. Further studies are needed to ascertain which wind conditions are most risky, whether they reduce the risk of crashing by avoiding taking off or landing under these conditions, and how the birds might be impacted by changing wind regimes. Simulating changes in wind speed and direction would aid in understanding the potential effects of wind as a factor of climate change on the local wind patterns and, subsequently, the population dynamics of Grey-headed Albatrosses breeding on Marion Island.

**Authors:**

Janine Schoombie¹, Stefan Schoombie², Kyle Goddard¹, Emily Shepard³, Peter Ryan⁴, Lelanie Smith¹, Ken Craig¹

¹University of Pretoria, ²Nelson Mandela Metropolitan University, ³Swansea University, ⁴FitzPatric Institute of African Ornithology, University of Cape Town

Wind-induced collision mortality in Grey-headed Albatrosses breeding on Marion Island

**Abstract:**

Marine birds are strongly exposed to weather conditions at sea but to date, few studies have investigated how wind or rainfall impacts time-activity budgets or foraging routines. We used data from GPS and pressure loggers to investigate the effects of wind speed and direction and rainfall on the three-dimensional foraging behaviour of gannets breeding at Bass Rock, Scotland. We found that activity budgets, travel speed and flight heights were all influenced by wind speed and direction. Time spent foraging increased in stronger winds but the birds could compensate for this by decreasing time spent on the water. Travelling flight height decreased with increasing head winds, potentially an additional behavioural buffer against adverse effects of strong headwinds. Rain had no discernible effect on foraging but the behavioural flexibility recorded is likely to be critical to maintaining nest attendance patterns and provisioning rates of chicks across variable environmental conditions encountered at sea.

**Authors:**

Jude Lane¹, Dominick Spracklen¹, Keith Hamer¹

¹University of Leeds

Effects of windscape on three-dimensional foraging behaviour in a wide-ranging marine predator, the northern gannet

**Abstract:**

Wind plays an important role in seabird ecology and evolution, shaping energetic costs at multiple scales. Quantifying those costs has been greatly simplified by the development of small accelerometers that can measure mechanical flight costs. To examine the effect of windscapes at multiple scales, I attached GPS-accelerometers to thick-billed murres, which have high flight costs and are very susceptible to the effect of wind. At short time scales, I show that individual birds alter their wing beat amplitude but not wing beat frequency in response to increased wind, confirming a key prediction from the Pennycuick model. These increased costs meant that air speed was not regulated 1:1 with wind speed, and so flight times increased when flying into head winds at the scale of minutes. At the scale of days, energetic costs were higher during periods of heavy winds, and birds typically avoided flying during those periods. Birds did not appear to use windscapes actively, choosing to alter their time budgets rather than space use in response to wind. Ultimately, this had little impact on chick growth rates as adults buffered the effect of stormy conditions by increasing feeding rates during calm conditions. In conclusion, wind had a strong impact on seabird energetics from the scale of seconds to days but buffered these impacts on their offspring.

**Authors:**

Kyle Elliott¹

¹McGill University

Using accelerometry to understand the effect of windscape from the scale of seconds to days

**Abstract:**

Locating ample food for self-maintenance and reproduction is a key challenge for wild animals, with consequences for individual fitness and population processes. The methods that individuals employ to locate food are partially shaped by environmental conditions that often vary spatio-temporally. In avian species, rain can affect behaviour, impairing senses and increasing energetic costs. However, the consequences of rain on movement behaviour are largely unexplored. We investigated the influence of rainfall on the foraging behaviour of a tropical seabird, the magnificent frigatebird Fregata magnificens. They are highly efficient flyers that can spend long time aloft, tracking environmental conditions to find foraging opportunities. Uniquely among seabirds, frigatebirds lack feather waterproofing and cannot dive nor perch on the water surface. Their foraging behaviour should thus be highly sensitive to the effects of rainfall. We tracked the foraging movements of 33 chick-rearing adults from a population in the Cayman Islands, central Caribbean. We firstly investigated whether foraging individuals avoided areas with high rainfall. We then assessed the broad-scale effects of rainfall on trip characteristics. Finally, we investigated fine-scale behavioural responses to local variation in rainfall, using Hidden Markov models that accounted for possible confounding effects of wind speed. Frigatebirds did not avoid areas with high rainfall during foraging trips, nor did rainfall influence trip characteristics. However, rainfall decreased time devoted to foraging-related activities and increased time spent perching. Moreover, it affected flight mode, inducing birds to fly slower and at lower altitudes. Wind speed, which was not correlated with rainfall, had a distinct effect, with strong winds affecting night-time behaviours by decreasing time spent perching. Our results indicate that rainfall does not affect the spatial distribution of foraging frigatebirds but does alter fine-scale foraging behaviour through reducing flight activity. Frigatebirds appear to cope with frequent rainfall events in tropical oceans by reducing their activity levels. We suggest that ongoing environmental changes in this region, through increasing storm frequency and intensity, has the potential to impair foraging and indirectly affect the fitness of these apex predators.

**Authors:**

Federico De Pascalis¹, Rhiannon Austin², Jonathan Green², John Arnould³, Simona Imperio⁴, Jane Haakonsson⁵, Jacopo Cecere⁴, Diego Rubolini¹

¹University of Milan, ²University of Liverpool, ³Deakin University, ⁴ISPRA, ⁵Government of the Cayman Islands

Storm riders or hiders: rainfall alters foraging activity in a tropical seabird

**Abstract:**

The remoteness of islands allowed for the evolution and maintenance of rich and endemic biodiversity, isolated from many pressures including anthropogenic ones. The increasing use of, and visitation to, these isolated territories by people (especially tourists) enables the investigation of how biodiversity reacts to novel pressures. Indeed, humans can have an indirect effect associated with their mere presence as wildlife responds to people as if they are predators. Seabirds for example rely on isolated, "low disturbance" areas to reproduce. They are one of the most threatened animal groups at a global scale and their risk of extinction is increasing faster than any other group of birds. We measured flight-initiation distances (FIDs) and monitored the breeding status of six seabird species breeding on tree islets of Coral Sea. We then developped a spatiality explicit sensitivity index considering both classical diversity metrics (species abundance and richness) and this behavioural metric of birds sensivity to human disturbance. Our prospective dataset first shows that seabirds sensivity to human disturbances varies between species and along their reproductive cycle. Shorter FID recorded during the most vulnerable stages of the reproduction, ie egg laying and chicks rearing, support the hypothesis of a 'sit and defend' strategy. Thereby, nest defence would likely be a better predictor of birds behavioural response than predation avoidance during critical reprodutive states. On the other hand, our spatially explicit index provides an innovative and promising sensibity metric by including seabirds behavioural responses to disturbances. In island contexts facing increasing pressures from human visitations and tourism, we believe that this index may address the need for conservation planning tools.

**Authors:**

Martin THIBAULT¹, Mike Weston², Andreas Ravache¹, Eric Vidal¹, Thomas Bouyard³

¹ENTROPIE (IRD), ²Deakin University, ³IRD

Flight-initiation response as a promising conservation planning tool on remote islets

**Abstract:**

In seabirds chick growth rates at early period would be determined survival of chicks after fledging. So, it is expected that parents with greater efforts provide more foods their chicks to be faster grow, especially at the early period. To determine this hypotheses we measured parental daily energy expenditure (DEE) of rhinoceros auklets Cerorhinca monocerata as parental effort and chick growth rates at early breeding stage (day of 5-20) at Teuri Island, Hokkaido, Japan in late May - July in 2018 and 2019. We measured daily energy expenditure (DEE) of parental birds at early chick stage (day of 14-19) using by doubly labelled water method and body mass of chicks daily until fledging. Chicks being greater grow at the early stage had larger body mass at fledging. However, there was no relationship between parental DEE and chick growth rates at the early period, and our hypotheses was not supported from the study. This result suggests that there is large individual variation in parental foraging efficiency; some parents could provide larger foods with greater DEE and others less foods with similar DEE to the former.

**Authors:**

Nao Nagatani¹, Masaki Shirai², Jumpei Okado¹, Yasuaki Niizuma³

¹Graduate school of Fisheries Sciences, Hokkaido University, ²Central Resaerch Institute of Electric Power Industry, ³Laboratory of Environmental Zoology, Meijo University

The Relation Between Daily Energy Expenditure of Parent and Chick Growth Rates at Early Breeding Stage in Rhinoceros Auklet

**Abstract:**

Since the early 1980s, NOAA Fisheries has been monitoring and mitigating for seabird bycatch. In 2001, the agency formed the National Seabird Program (NSP) to coordinate seabird protection, and today it is a cross-cutting group of managers and scientists working domestically and internationally to protect and conserve seabirds. The program's activities are guided by statutes and agency priorities which form the basis for NSP's two key goals: 1) Monitor and mitigate seabird bycatch - NOAA Fisheries is responsible for bycatch in U.S. fisheries and supports bycatch reduction associated with non-U.S. fisheries, and 2) Promote seabirds as ecosystem indicators. As highly migratory, near-apex predators, seabirds integrate across trophic levels, space, and time, are easy to detect and identify, can be surveyed over various spatial scales, and are responsive to environmental change. In 2019, NSP finalized a five-year strategic plan to promote awareness and value of seabirds, foster collaboration, and coordinate and direct resources to accomplish its objectives. These included: 1) monitor and estimate seabird bycatch; 2) mitigate seabird bycatch; 3) strengthen key partnerships; 4) promote seabirds in advancing ecosystem-based fisheries management; and 5) elevate awareness of and support for the NSP. In practice, the program's approach to achieving its goals has been supporting field and laboratory research, ensuring our representation on working groups and steering committees within and external to NOAA Fisheries, and partnering with NOAA Offices, FMCs, States, and other Federal agencies. Other actions are coordinating and providing seabird expertise for policy and management decisions, conducting research, fieldwork, and outreach through agency reports and peer-reviewed publications. Seabirds are the world's most threatened bird group, and NOAA Fisheries' National Seabird Program continues to support seabird conservation both nationally and internationally.

**Authors:**

Annette Henry¹, Trevor Joyce¹, Lee Benaka¹, Shannon Fitzgerald¹, Thomas Good¹, Jason Jannot¹, Mi Ae Kim¹, Robert Suryan¹, Jeannette Zamon¹, Lisa Ballance²

¹NOAA Fisheries, ²Oregon State University

NOAA Fisheries' National Seabird Program: advancing conservation, sustainable fisheries, and ecosystem-based management

**Abstract:**

An oceanic warming anomaly that peaked during 2015-2016 impacted broad areas of the North Pacific, including areas with concentrations of breeding and overwintering seabirds in the Northern Gulf of Alaska. We monitored colony attendance, productivity, and seasonal distribution of seabirds in the Kenai Fjords area prior to, during, and following the oceanic warming event. We used remote camera observation techniques to observe breeding colonies of Black-legged Kittiwake (Rissa tridactyla) and Common Murre (Uria aalge), and vessel based surveys to observe seasonal distribution of marine birds. We observed a reduction in colony attendance during the warming event. Productivity remained relatively similar prior to and during the warming event through 2015, but little or no productivity was observed during 2016-2017. The first signs of recovery in productivity were observed in 2018, with continued improvement in 2019. During the winter of 2015-2016, a large-scale mortality event of Common Murres occurred in Alaska, including our study area. Preceding and during the mortality event, a redistribution of pelagic Common Murres to nearshore waters was observed. Reasons for the redistribution and large-scale mortality of Common Murres are not fully understood, but have been linked to changes in prey availability, leading to starvation, and other contributing factors. Our study provided data characterizing demographic impacts of oceanic warming events on two species of seabirds with different foraging strategies, and provided evidence that recovery from such events may take multiple years due to lingering effects on nest site attendance and productivity.

**Authors:**

Tuula Hollmen¹, John Maniscalco², Sadie Ulman², Sarah Tanedo¹

¹University of Alaska Fairbanks and Alaska SeaLife Center, ²Alaska SeaLife Center

Demographic response of seabirds along the Kenai Fjords coast in the Northern Gulf of Alaska to a 2015-2016 marine heatwave

**Abstract:**

Phillip Island, Australia is home of one of the largest colonies of Little penguins, with over 32,000 breeding adults. Little penguins have been studied on the island since 1968. As sick and injured penguins were regularly found, a purpose-built Wildlife Clinic opened in the 1980s. Today, the Clinic cares for approximately 150 Little penguins annually, in addition to 300-400 other animals of over 60 different species. Rehabilitation success is often based on the number of animals successfully released from care. However, the fate of rehabilitated animals is hardly known or reported. Knowing the success of the rehabilitation efforts would allow for an assessment of the resources used as well as evaluating whether rehabilitated animals recover from the stress undergone while in care. Here we propose a more accurate indicator of success based on how many individuals are resighted after release. This study looked at how many adult Little penguins were resighted within a 12-year period (2005-2017) after being released from the Wildlife Clinic. The resight rates of Little penguins after rehabilitation was 49%, compared to 64% resight of control birds (penguins that were not rehabilitated), which was significantly different, χ2 (1, N = 107) = 5.50, p < 0.05. Although the difference between resights of the Clinic and the control birds was significantly high, almost half of the rehabilitated birds were sighted again in the breeding colony. Given the increasing number of diseases, incidents with human-penguin interactions and negative effect of climate on penguin food supply, the penguin rehabilitation efforts are worth doing.

**Authors:**

Paula Wasiak¹, Jodi Bellett¹, Rose Baulch¹

¹Phillip Island Nature Parks

Keeping up with the tubenoses: Vegetative succession and seabird activity during passive island recovery

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Keeping up with the tubenoses: Vegetative succession and seabird activity during passive island recovery

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Effects of wind on seabird foraging in the North East Atlantic

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Plastic ingestion in albatrosses and petrels off the shores of Argentina and Brazil

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