Academic literature on the topic 'Migratory seabird'

Seabirds exhibit physiological adaptations that allow them to forage in the marine environment and undertake long-distance migrations during non-reproductive periods. As a result, they face various natural and anthropogenic pressures, which can lead to extreme fatigue and even death. Stranded bodies that float in the sea can wash ashore, providing valuable ecological information. This study aimed to analyze seabird strandings along the south and southeast coasts of Brazil between 2016 and 2019, focusing on spatiotemporal and potential environmental and anthropogenic influences. Using data from the Santos Basin Beach Monitoring Project, we calculated ecological indices of abundance, richness, and diversity for the entire seabird community and separately by migratory behavior (resident, southern migratory, northern migratory). Statistical modeling revealed a strong decreasing trend in strandings from south to north, with higher events on the southern coast (Santa Catarina and Paraná) and lower on the southeast coast (São Paulo). Resident species and northern migratory species showed peak strandings in spring, while southern migratory peaked in winter. These spatial and temporal patterns reflected birds’ home ranges, reproductive cycles, and migratory behaviors. Environmental variables influenced strandings differently depending on species migration behavior and ecological indices, highlighting the role of oceanographic processes in carcass drift and the impact of climatic events on species mortality. This study is the first to demonstrate a spatiotemporal pattern of seabird strandings on the Brazilian coast, providing valuable insights into seabird dynamics in the Santos Basin and offering important data for conservation efforts.

Upwelling regions are highly productive habitats targeted by wide-ranging marine predators and industrial fisheries. In this study, we track the migratory movements of eight seabird species from across the Atlantic; quantify overlap with the Canary Current Large Marine Ecosystem (CCLME) and determine the habitat characteristics that drive this association. Our results indicate the CCLME is a biodiversity hotspot for migratory seabirds; all tracked species and more than 70% of individuals used this upwelling region. Relative species richness peaked in areas where sea surface temperature averaged between 15 and 20°C, and correlated positively with chlorophyll a , revealing the optimum conditions driving bottom-up trophic effects for seabirds. Marine vertebrates are not confined by international boundaries, making conservation challenging. However, by linking diversity to ocean productivity, our research reveals the significance of the CCLME for seabird populations from across the Atlantic, making it a priority for conservation action.

Abstract This study investigates the temporal taxonomic variation of the seabird community, and the spatial distributions of seabirds in the Laje de Santos Marine State Park (PEMLS) and surrounding waters, based on shipboard surveys. The increase in the number of seabird taxa during winter is associated to the presence of migratory birds from the south. During summer, only resident species were observed within the park. Analysis of the spatial distributions of taxa using geographic information systems (GIS) identified three different regions within the study area. The first was close to the coast, where birds interact with fishing activities in search for food; the second was the nesting area that provides shelter for the breeding colonies; and the third, which is farther offshore and more exposed, where a higher number of migratory birds were observed during winter surveys. The PEMLS and surrounding waters have characteristics that are important for the study and preservation of seabirds in Brazil and for the South Atlantic Ocean.

Migratory seabirds face threats from climate change and a variety of anthropogenic disturbances. Although most seabird research has focused on the ecology of individuals at the colony, technological advances now allow researchers to track seabird movements at sea and during migration. We combined telemetry data on Onychoprion fuscatus (sooty terns) with a long-term capture-mark-recapture dataset from the Dry Tortugas National Park to map the movements at sea for this species, calculate estimates of mortality, and investigate the impact of hurricanes on a migratory seabird. Included in the latter analysis is information on the locations of recovered bands from deceased individuals wrecked by tropical storms. We present the first known map of sooty tern migration in the Atlantic Ocean. Our results indicate that the birds had minor overlaps with areas affected by the major 2010 oil spill and a major shrimp fishery. Indices of hurricane strength and occurrence are positively correlated with annual mortality and indices of numbers of wrecked birds. As climate change may lead to an increase in severity and frequency of major hurricanes, this may pose a long-term problem for this colony.

Migratory animals such as seabirds, salmon and whales can transport large quantities of nutrients across ecosystem boundaries, greatly enriching recipient food webs. As many of these animals biomagnify contaminants, they can also focus pollutants at toxic levels. Seabirds arguably represent the most significant biovectors of nutrients and contaminants from the ocean to the land, given their sheer numbers and global distribution. However, long-term census data on seabirds are rare. Using palaeolimnological proxies, we show that a colony of Arctic seabirds has experienced climate-induced population increases in recent decades. We then document increasing concentrations of contaminants, including polychlorinated biphenyls and cadmium, in pond sediments that are linked to biotransport by seabirds. Our findings suggest that climate-related shifts in global seabird populations will have the unexpected consequence of restructuring coastal ecosystems.

The Arctic tern is an iconic seabird, famous for its annual migrations between the Arctic and the Antarctic. Its wide geographical range has impeded knowledge of potential population bottlenecks during its annual bi-hemispheric movements. Although Arctic terns breed in the Pacific, Atlantic, and Arctic coasts of North America, few tracking studies have been conducted on North American Arctic terns, and none in Canada, which represents a significant proportion of their circumpolar breeding range. Using light-level geolocators, we tracked 53 Arctic terns from 5 breeding colonies across a wide latitudinal and longitudinal range within North America. We compared the routes taken by birds in our study and migration timing to those previously tracked from Greenland, Iceland, The Netherlands, Sweden, Norway, Maine (USA), and S. Alaska (USA). Most Arctic terns tracked globally used one of 3 southbound migration routes: (1) Atlantic West Africa; (2) Atlantic Brazil; and (3) Pacific coastal, and one of 2 northbound migration routes: (1) Mid-ocean Atlantic and (2) Mid-ocean Pacific. Some other trans-equatorial seabirds also used these migration routes, suggesting that Arctic tern routes may be important for other species. The migration timing for southbound and northbound migrations was generally different between tracked tern colonies worldwide but generally fell within a 1-2 mo window. Our research suggests that conservation management of Arctic terns during their migration should dynamically adapt with the times of the year that terns use parts of their route. Future identification of common multi-species seabird flyways could aid the international negotiations required to conserve pelagic seabirds such as Arctic terns.

Seabirds in the 10 migratory bird sanctuaries of the North Shore of the Gulf of St. Lawrence, Quebec, Canada, which were created in 1925, have been censused regularly for the last 85 years. The sanctuaries support 16 seabird species, many of which are found in significant numbers. From 2005 to 2010, some notable population changes were observed: large increases in Common Murres (Uria aalge), Razorbills (Alca torda), and two species of cormorants and continuing declines in Black-legged Kittiwakes (Rissa tridactyla) and Atlantic Puffins (Fratercula arctica). The status of Leach’s Storm-Petrel (Oceanodroma leucorhoa) and Caspian Tern (Hydroprogne caspia) is extremely precarious because of their small breeding populations. Between 2005 and 2010, seabird numbers in the sanctuaries increased 19% overall and were stable in most sanctuaries (≤ 15% change); however, notable increases were observed at Îles Sainte-Marie (60%), Baie des Loups (47%), and Île à la Brume (44%). Nonetheless, considering historical records, increased surveillance and raising of awareness of seabird conservation in local communities near the sanctuaries of Île à la Brume, Baie des Loups, and Saint-Augustin would be most beneficial.

In 1925, ten migratory bird sanctuaries were created on the North Shore of the Gulf of St. Lawrence, and their breeding seabird populations have been censused every five years since. Between 2010 and 2015, only three alcid species exhibited positive population trends (Razorbill [Alca torda], Common Murre [Uria aalge], and Atlantic Puffin [Fratercula arctica]), while the remaining 13 species showed declining trends. Leach’s Storm-Petrel (Hydrobates leucorhous) and Caspian Tern (Hydroprogne caspia) are on the verge of disappearing from the sanctuaries, and the prolonged and rapid decline in Black-legged Kittiwake (Rissa tridactyla) is worrisome. Based on historical records since 1925, it appears that seabird communities are faring well in some sanctuaries (e.g., Baie de Brador, Îles aux Perroquets, and Îles Sainte-Marie), while numbers are at low levels in others (e.g., Île à la Brume, Baie des Loups, and Saint-Augustin). Human disturbance, harvest of seabirds (eggs and birds), and predation are among the issues potentially most affecting seabird populations on the North Shore of the Gulf of St. Lawrence.

Portuguese waters are an important migratory corridor for European seabirds and coast-based counts can be used to monitor local and global populations and to study the long-term trends in seabird populations. After 10 years of counts in seven different sites along the Portuguese coast, we aimed to identify the period of occurrence and distribution areas of the seven most common seabird species, evaluate abundance trends and associations with potential oceanographic drivers. The trim model was able to estimate the trend for most of the species with the Balearic Shearwater, the Great Skua, and the post-breeding populations of Sandwich Tern and Common Scoter presenting strong negative trends. The Mediterranean Gull and the Northern Gannet during the pre-breeding migration show a moderate increase. The GAMs found that the abiotic parameters that most often had a significant influence in the models were sea surface temperature, ocean mixed layer thickness and eastward wind speed; O uso da costa Portuguesa pelas aves marinhas migratórias Resumo: As águas portuguesas são um importante corredor migratório para as aves marinhas europeias e, contagens a partir da costa podem ser utilizadas para monitorizar e mostrar as tendências a longo prazo das populações de aves marinhas. Após 10 anos de contagens, pretendeu-se identificar o período de ocorrência e áreas de distribuição das sete espécies mais comuns, avaliar as tendências de abundância e potenciais associações com variáveis ambientais. O trim estimou a tendência para quase todas as espécies, com a pardela-balear, o alcaide e, as populações pósreprodutoras de garajau-de-bico-preto e da negrola a apresentarem acentuadas tendências negativas. A gaivota-de-cabeça-preta e a população pré-reprodutora do alcatraz apresentam um aumento moderado. Os GAMs indicam que os parâmetros abióticos que mais frequentemente tiveram uma influência significativa nos modelos foram a temperatura da superfície do mar, a espessura da camada mista do oceano e a velocidade do vento vindo de Este.

Movement is a widespread characteristic in the animal kingdom —occurring at many spatiotemporal scales— with consequences at an individual, population, species, and even ecosystem level. It is a very diverse character, with many different drivers that stem from the way in which individuals interact with their environment. Of these, one of the most important is the distribution of resources, particularly for migratory and foraging movements. In migration, the search for an optimal environment involves movement at large spatiotemporal scales, following seasonal changes in resource distribution. In foraging movements, the search for resources happens at small spatiotemporal scales, and involves different strategies to optimise the search and capture of food, including the ability to obtain foraging cues from conspecifics. In seabirds, movement —at large and local scales— has deep repercussions in their life-history traits, evolutionary history, morphology, physiology and behaviour, which makes them a very valuable study group to understand the role, the causes and consequences of migratory and foraging movements in the ecology of marine top- predators. The study of migratory and foraging movements has been revolutionised by the development of smaller, cheaper and better tracking devices, promoting multi-colony, population and even species approaches to the study of animal movement, but which also come with a set of methodological challenges that have to be addressed in order to make unbiased inferences of space and habitat use at population or species level from individual movement data. In this thesis, we develop methods to test the possible biases introduced by the use of individual tracking data to infer distribution at a population or species level. we then apply these tools to a multi-colony dataset of non-breeding locations of Cory’s (Calonectris borealis), Scopoli’s (C. diomedea) and Cape Verde (C. edwardsii) shearwaters, to study their migratory connectivity and non-breeding habitat segregation at the colony, population and species level. Lastly, we apply state-of-the-art spatial models to study foraging distributions of three neighbouring colonies of Cory’s shearwaters, detect the segregation among them and unravel the environmental and behavioural drivers of this segregation. I developed several functions in the R environment aimed at the detection of the effects of individual site fidelity and temporal variability in the inference of spatial use at a colony or population level, and to calculate the degree in which the movements of a single population can be representative of those of the entire species. These tools are applicable to individual movement data regardless of the species or tracking device. we also used these tools to demonstrate the spatial and ecological segregation between the non-breeding distributions of three taxa of Calonectris shearwaters studied, as well as detecting a stronger degree of migratory connectivity at a population than at a colony level, indicating that individuals of different colonies within a population mix in the non-breeding areas, but birds from different populations do not, which has important implications for their population dynamics and for their conservation and management. Lastly, we demonstrated segregation among the foraging distributions of three neighbouring colonies of Cory’s shearwaters, both in the waters surrounding the colony and in distant, foraging grounds, finding evidences of both environmental and behavioural drivers behind this segregation, and suggesting a mechanism through which transfer of information between individuals can be shaping the distributions of foraging seabirds. The results of this thesis provide relevant tools for the field of movement ecology, as they can be used for analysing movements of mobile species, regardless of species, tracking device or spatiotemporal scale. In addition, they are relevant for the field of seabird ecology as they provide insights into the causes of space and habitat use in long-ranging pelagic seabirds.<br>El moviment és una característica omnipresent en el regne animal, a les més diverses escales espacio-temporals i amb conseqüències a diferents nivells (individual,. poblacional, específic i fins i tot ecosistèmic). La força impulsora del moviment més predominant i generalitzada és distribució dels recursos en el medi, important tant a gran escala (moviments migratoris) com en els moviments diaris de recerca d’aliment a escala petita. En les aus marines en particular, el moviment té repercussions profundes en les seves característiques morfològiques i de comportament, en la seva història de vida, i la seva història evolutiva. El desenvolupament de dispositius de seguiment més petits, barats i precisos ha promocionat la proliferació d’estudis del moviment animal des d’un punt de vista multi- colònia, de població i fins i tot d’espècie. En aquesta tesi, desenvolupo diferents funcions per testar els biaixos introduïts en l’estudi del moviment, a través de dades de seguiment individual, a nivell de població o espècie. Posteriorment, utilitzo aquestes eines per a analitzar la connectivitat migratòria i la segregació dels hàbitats d’hivernada, des d’un punt de vista multi-colònia, de les baldrigues cendroses de l’Atlàntic (Calonectris borealis), del Mediterrani (C. diomedea), i de Cap Verd (C. edwardsii). Per últim, aplico un mètode innovador de modelatge espacial per a estudiar les distribucions d’alimentació de baldrigues cendroses de l’Atlàntic criant en tres colònies veïnes, per detectar-ne la segregació i descobrir-ne les causes, tant ambientals com comportamentals, incloent com els diferents mecanismes de transferència d’informació entre individus poden afectar a aquestes distribucions. Els resultats d’aquesta tesi tenen rellevància per a la ecologia del moviment en general, ja que són aplicables a dades de moviment individual de qualsevol espècie, independentment de l’aparell de seguiment utilitzat, i en el camp de l’ecologia de les aus marines, ja que proporciona nous coneixements sobre els diferents factors afectant la distribució i l’ús de l’espai, tant durant la cria com durant la hivernada, en aus pelàgiques.

L’Arctique, bien que région éloignée de toutes activités anthropiques intensives, est contaminé par les polluants émis à de plus basses latitudes. En effet, les caractéristiques physico-chimiques de certains polluants leur permettent d’être transportés sur de longues distances, via les courants atmosphériques ou océaniques. Parmi eux se trouve notamment le mercure (Hg), élément trace non-essentiel naturellement émis dans l’environnement mais dont les émissions d’origine anthropiques ont fortement augmenté depuis le 19ème siècle. Ce neurotoxique engendre chez les espèces animales des troubles comportementaux, mais aussi des problèmes de reproduction et dans les cas extrêmes, la mort. Le milieu marin est particulièrement sensible à la contamination au Hg. En effet, une fois dans l’environnement marin, le Hg intègre la chaine alimentaire (sous sa forme toxique méthylée - MeHg), dans laquelle sa concentration augmente d’un niveau trophique à l’autre (processus de bioamplification) et/ou accumule au sein des organismes (processus de bioaccumulation). Ainsi, les prédateurs supérieurs longévifs tels que les oiseaux marins, en fin de chaine alimentaire, présentent les concentrations de Hg parmi les plus élevées. Ils sont largement et efficacement utilisés comme bio-indicateurs de la contamination au Hg de leur environnement. La majeure partie des connaissances actuelle sur la contamination au Hg des oiseaux marins Arctique concerne la saison de reproduction, durant laquelle les concentrations varient spatialement, avec notamment les concentrations les plus élevées trouvées en Arctique Canadien. Durant cette période, qui ne représente qu’une partie de l’année, les oiseaux se reproduisent à terre et sont donc plus facilement accessibles. Mais une fois la saison de reproduction terminée, la majorité des oiseaux marins migrent en haute mer, en dehors de l’Arctique. Une étude précédente a montré qu’une population de mergules nains (Alle alle) se reproduisant à l’Est du Groenland a des concentrations de Hg plus élevées en période de non-reproduction qu’en période de reproduction, avec des effets délétères sur la reproduction suivante. Au cours de ce travail de thèse, et grâce à une approche multi espèces et multi colonies, nous nous sommes intéressés au rôle de la migration des oiseaux marins sur leur contamination au Hg et ce à l’échelle de l’Arctique. Nos résultats montrent une saisonnalité dans la contamination au Hg, nous permettant d’étendre les résultats mis en avant pour les mergules nains à de nombreuses autres espèces d’oiseaux marins. Nous avons également trouvé que cette saisonnalité varie spatialement avec des variations saisonnières plus importantes pour les populations se reproduisant en Atlantique Ouest (Ouest du Groenland et Est du Canada). Ces résultats nous ont amenés à faire l’hypothèse que cette variation était une conséquence de la migration des oiseaux marins et de la distribution de leur zone d’hivernage. Pour tester cette hypothèse, nous avons utilisé les oiseaux comme bio-indicateurs de leur environnement. Pour cela, nous avons combiné des analyses de Hg avec du biologging afin de retracer l’origine spatiale de la contamination hivernale au Hg. Nos résultats montrent une augmentation des concentrations de Hg suivant un gradient est-ouest nous permettant ainsi d’étendre les résultats des précédentes études concernant la période de reproduction à l’hiver et à l’ensemble des régions marines à l’échelle de l’Atlantique Nord - Arctique. Ainsi, les résultats du présent travail de thèse nous permettent de conclure qu’au-delà de leur migration, ce sont les zones de reproduction et d’hivernages des oiseaux marins arctiques qui conditionnent leur contamination au Hg<br>The Arctic, even far from intensive human activities, is contaminated by pollutants emitted at Northern mid-latitudes. Because of their physico-chemical characteristics, pollutants are transported over large distances through atmospheric or oceanic currents. Among them is mercury (Hg), a naturally occurring and non-essential trace element whose emissions increased since the 19th century because of human activities. This neurotoxic negatively impacts animals’ health and induces behavioral changes, reproduction issues and in the most extreme case, death. The marine environment is particularly sensitive to Hg, which incorporates the food chain (under is toxic and methylated form – MeHg) in which its concentration increases from one trophic level to the other (e.g. biomagnification process) and accumulates within organisms (e.g. bioaccumulation process). Hence, long-lived top predators like seabirds, found at the end of the food chain usually show some of the highest contamination to Hg. They are commonly and efficiently used as bio-indicators of the health of their environment. Most of the current knowledge about Hg contamination in Arctic seabirds focused on the breeding period during which Hg was found to spatially vary, with usually higher Hg concentrations in the Canadian Arctic. During this period, which represents a part of the year only, seabirds aggregate in colonies for reproduction where they are more easily accessible. However, at the end of this period, seabirds migrate to overwinter mostly in open seas, outside of the Arctic. A previous study on a little auk (Alle alle) population breeding in East Greenland found that Hg concentrations were higher during the non-breeding period than during the breeding period, with carryover effects on the following reproduction. In the present doctoral work, based on a multi-species and multi-colony approach, we studied winter Hg exposure and the role of seabird migration in their contamination to Hg at large spatial scale. We found a seasonality in Hg concentrations allowing us to extend the results found in little auks to several species and at a larger spatial scale. We also found that this seasonality was spatially different with some of the highest variations for seabirds breeding in the West Atlantic (West Greenland and Canadian Arctic). We therefore proposed that such variations were due to seabird’s migration and the areas they overwintered at. To test such hypotheses, we used seabirds as bio-indicators of winter Hg contamination through the North-Atlantic Arctic. More specifically, we combined Hg measurements with geolocators devices to track the spatial origin of winter Hg contamination. We found an east-west increase in Hg concentrations allowing us to extend the results found during the breeding period to the winter period, through the entire North-Atlantic Arctic marine region. Results of the present doctoral work allow us to conclude that beyond migration, seabird distribution during the breeding and non-breeding periods drive their contamination to Hg

First published in 1994, The Complete Guide to Finding the Birds of Australia was the first ever book of its type in Australia – a complete guide to locating every resident bird species in Australia, plus supplementary information on where to find rarities, migratory species and logistical information.&#x0D; This fully revised second edition expands on the best-selling appeal of the first, describing the best-known sites for all of Australia’s endemic birds, plus vagrants and regular migrants such as seabirds and shorebirds. It covers all states and territories, and is the first guide to include all of Australia’s island and external territories. A comprehensive Bird Finder Guide details site information on all Australian bird species, and the authors provide valuable travel advice, including transport, climate and accommodation.&#x0D; Profusely illustrated with colour photographs of interesting, unique or unusual Australian birds, this book is a must-have for all birdwatchers living in Australia or visiting from overseas.

Abstract Cassin’s Auklets Ptychoramphus aleuticus are wing-propelled diving seabirds which feed extensively on krill and small fish of various species. Cassin’s Auklets are generally migratory; however, our study population on Southeast Farallon Island, California, is sedentary (Ainley et al. 1990). Here, its breeding biology, demography, foraging ecology, and diet have been studied since 1969. On Southeast Farallon, these birds nest in burrows or natural rock crevices. Birds will also use nest boxes which greatly facilitates research and monitoring. Cassin’s Auklets are nocturnal in their visits to breeding colonies owing to predation on adults by diurnally active Western Gulls Larus occidentalis.

Abstract This is a book about behavior and its ecological consequences, and specifically it is a book about a particular kind of behavior known as migration.Migration is one of several types of movement, all of which sum over the course of an organism’s life cycle to produce a lifetime track(Baker 1978). Before proceeding to a full discussion of migratory behaviour and its evolution and ecology, I shall briefly define and describe movements and related behaviors that organisms display, including some examples and an adumbration of their roles in life cycles (Table 1-1). This taxonomy should serve to place migration in the context of the lifetime track and to indicate its significance to life histories. I then consider in greater detail a definition and description of migration in Chapter 2.Most movements occur within a relatively circumscribed area or home rangeover which an organism travels to acquire the resources it needs for survival and reproduction. The sizes of home ranges depend on the habitat and the size and powers of movement of their residents. Most cover only a small area relative to the range of the organism, but some, like those of pelagic seabirds, may extend over considerable portions of the earth’s surface.

A cadre of environmental regulations and the associated permits and authorizations require offshore wind (OSW) energy to be planned, constructed, and operated in ways that avoid, minimize, and mitigate environmental impacts, including potential harm to wildlife. Wind energy areas (WEAs) are often rich with birds under protection by the Migratory Bird Treaty Act (MBTA) and some species are also protected by the Endangered Species Act (ESA). Some birds (e.g., albatross, shearwaters, and petrels) may be more vulnerable to collision with OSW turbines because of their reliance on wind-rich areas to propel their long-distance movements from distant breeding areas to foraging grounds offshore of the West Coast of the U.S.; flight can occur during the day or night, and at heights overlapping rotor-swept zones. In cases where OSW has the potential to kill or injure birds and/or bats, consultation and authorization by the U.S. Fish and Wildlife Service is required. For birds protected by the ESA, proposed wind energy projects will likely be required to generate collision risk models (CRMs) capable of estimating species-specific impacts anticipated over the permit term and recognizing uncertainty about these estimates. CRMs are most sensitive to avoidance rate, which must be calculated from interactions occurring at the following three scales: macro (avoidance of the wind farm as a whole), meso (avoidance of individual turbines or rotor-swept zones either through active detection and avoidance or as the result of species-specific flight and habitat use patterns), and micro (last-second measures taken to avoid collision) (Figure 1). To generate CRMs prior to construction requires extensive species-specific metrics from the project site such as: passage rate through the wind facility and rotor-swept zones; interannual variability in passage rates; turbine avoidance and attraction at multiple scales (macro, meso, and micro) (Cook et al. 2018); seabird or bat behaviors (foraging, transiting, seasonal migration, nocturnal activity, etc.); seabird and bat flight characteristics (speed over ground, position in rotor-swept zones, direction relative to wind, maneuverability, style of flight); seabird and bat size; and additional considerations of environmental covariates of collision (i.e., conditions that modify collision risk). Developing technology that can address this critical knowledge gap for most of the seabirds that occur off the U.S. west coast where floating OSW projects are proposed will allow wind energy proponents to avoid or minimize detrimental scenarios and achieve renewable energy generation targets. Real-time, automated monitoring technologies for seabird and bat detection, identification, and characterization at multiple scales will increase understanding and reduce uncertainties associated with potential interactions between seabirds and bats with OSW technologies, and reduce the timeline and costs associated with environmental permitting.

Migratory seabirds are an unseen conduit between marine and terrestrial systems, carrying the nutrients they consume at sea into the forests where they breed. Acting as environmental sentinels, their health and reproductive success provide early warning signals of deteriorating marine eco-systems as the climate changes, and fish stocks decrease. Aotearoa New Zealand is the seabird capital of the world, with ~25% of all species breeding here and ~10% exclusively so. They play a critical role in maintaining healthy ecosystems, with their long-term well-being is closely interconnected with our own prospects for a sustainable future. Now predominantly restricted to off-shore islands due to predation and habitat destruction, seabirds and their familiar sounds have become less available in an age when the unprecedented global movement and planetary spread of the human population has culminated in unsustainable fishing, predators and habitat destruction. Inspiring mythology, song, poetry and stories, birds have been significant in shaping our understanding of how our natural environment has come to be known and understood. This paper speculates upon how we learn to communicate and cooperate with these precious taonga, and what might be learned from such an exchange through creative practice. Reflecting upon what birds might tell us, musician Matthew Bannister and I, a visual artist, have taken our cue from seabirds sharing our local environment on the west coast of Aotearoa - from the petrel (peera) through to the gannet (tākapu). Working on the premise that bird vocalisation is a performed negotiation that includes defence of territory and mate attraction, a bird’s call is a form of communication that effectively says “Come here” or “Go away”, which arguably is true of music – marking a social space and time to invite or repel. Rather than limiting bird calls to functionalist categories of explanation, we ask whether seabirds can communicate and exchange information about environmental changes using a malleable vocabulary, comprised of unique acoustic units arranged and re-arranged sequentially for greater communicative depth. Granting a high level of agency and creativity to birds as opposed to believing a bird only avails itself of stereotyped ‘speech’ to survive an accident-rich environment, places greater importance on responses that are improvised directly upon environmental stimuli as irritant rather than as a signal. Matthew explores bird calls via musique concrète, sampling recordings of seabirds to abstract the musical values of bird song conventions – a human response to the ‘other’ in jointly formed compositions, reflecting a living evolving relationship between composer and bird. In further developing our research into a multimedia artwork, I shall extend a technique used for electroacoustic composition (granular synthesis) to video portraits of composer/performer and bird. In applying granular synthesis techniques to video, tiny units of image and sampled sound are reassembled within the frames. Through the mixing of existing synthesised sequences, performer/composer and bird become active participants in the making and remaking of a shared environment, articulating the limits of space/territory to find new ways to be heard within it.

Large areas of shallow, sandy seas are covered by migrating tidal sand waves. Sand wave migration rates are on the order of 10s of meters per year, with heights between 10 and 30% of the water depth. If such regions are traversed by pipelines, the dynamic interaction between the rock-berm protection of the pipelines and the migratory sand waves must be accounted for to assure the long term stability of both the rock-berms and pipelines. This study employs a 2DV model to demonstrate the hydrodynamic and morphodynamic interaction between migrating sand waves and a rock-berm constructed perpendicular to the migration direction. The timescale of sand waves and the design life of rock-berm are similar, consequently, rock-berms in sand wave regions experience a change in bed level approximately equal to that sand wave height. Due to the large difference in temporal scales between local erosive processes and sand wave migration, the passing of a sand wave is manifest as a general rising or falling of the ambient seabed, while a rock-berm is fixed at its construction elevation. Consequently, the critical design case is for a rock-berm constructed at a sand wave crest since the surrounding bed level decreases throughout the operational life of the pipeline. A conservative design approach is to construct rock berm protection in a sand wave trough, resulting in rising ambient seabed levels throughout the operational lifetime of the underlying pipeline or electrical cable.