Seabird species are increasingly threatened around the world due to a range of anthropogenic impacts affecting at-sea and breeding habitat. One such species is the Ancient Murrelet, an Alcid species nesting on the Pacific Coast of Canada. Ancient Murrelets are an important species in Canadian waters as approximately 50 % of the world’s breeding population nest in a small region of the British Columbia coast. Ancient Murrelets are listed as a species of Special Concern, due to threats in their breeding colonies; threats to their at-sea habitat, such as disturbance from shipping traffic, oil pollution, and fisheries bycatch, are currently poorly- documented due to the challenges associated with studying seabirds in their offshore environments. Conservation efforts to protect this species require information on movements and habitat use at sea. Therefore, there exists a critical need for research that provides new knowledge on where murrelets are travelling and the habitats in which they are foraging. The objective of this thesis research is to investigate movement behaviour and at-sea habitat of Ancient Murrelets during breeding season foraging trips. Movement modelling using hidden Markov models differentiated the tracks into behaviour states, and identified foraging locations at sea. Foraging locations were used in regression modelling to investigate the degree to which variability in Ancient Murrelet foraging locations could be explained by seafloor depth, slope and tidal current, and spatial measures such as distance from the breeding colony. From characteristics of movement paths, hidden Markov models identified three movement behaviour states, which were interpreted as transit, resting, and foraging behaviours. Logistic regression models suggested that depth, seafloor slope, tidal speed, and distance from the colony exhibited a negative influence on locations where birds chose to forage. Nevertheless, of the locations where foraging took place, foraging intensity was found to be higher in deeper areas suggesting Ancient Murrelets may be focusing efforts in areas of higher prey abundance. The combination of individual movement analysis and habitat analysis provides an important first step in gaining a greater understanding of Ancient Murrelet behaviour and foraging habitat at sea. These findings can inform marine management planning in this region and conservation of this vulnerable species. / Graduate / 2021-04-17

Seabirds – broadly defined as any bird species associated with the marine environment – are exposed to a wide range of environmental contaminants. Vectors of exposure to metal pollution include by external contact, inhalation, and most often ingestion of food and incidental seawater. Seabirds are often considered marine ecosystem bioindicators due to their high trophic position, relatively long lifespan, and wide geographic ranges. We examined the concentration of total mercury (THg), lead (Pb), and cadmium (Cd), in the kidney, liver, breast muscle, and feathers of seven species of juvenile and adult seabirds commonly found in South Florida: brown pelican Pelecanus occidentalis (n=16), northern gannet Morus bassanus (n=16), double-crested cormorant Phalacrocorax auritus (n=15), royal tern Thalasseus maximus (n=15), herring gull Larus argentatus (n=9), laughing gull Leucophaeus atricilla (n=15), and osprey Pandion halietus (n=15). Trace amounts of lead and cadmium were found in the subsample of birds tested, suggesting that the birds living in south Florida do not face a significant threat from those metals. Results of total mercury in 101 specimens ranged from 0 to 45.07 mg/kg (dry wt), 0.15 to 132.13 mg/kg (wet wt), 0.06 to 352.35 mg/kg (wet wt), and 0.06 to 23.43 mg/kg (wet wt) in feathers, liver, kidney, and breast muscle respectively. Individual birds found to have the highest levels of total mercury were collected from centers in Monroe County. Osprey showed the highest total mercury values overall. These findings suggest a potential link to the Everglades and runoff into the Florida Bay, thus possibly exposing birds who utilize the Florida Bay at a higher risk for mercury poisoning.

Endoparasite community structure has been poorly studied in migratory birds, particularly among the seabirds of south Florida. We examined parasite communities in seven south Florida seabird species: brown pelican Pelecanus occidentalis (n=33), northern gannet Morus bassanus (n=31), double-crested cormorant Phalacrocorax auritus (n=33), osprey Pandion haliaetus (n=27), royal tern Thalasseus maximus (n=30), herring gull Larus argentatus (n=12), and laughing gull Leucophaeus atricilla (n=40). We identified 33 parasitic helminth species: 6 nematodes, 2 cestodes, 3 acanthocephalans, and 22 digeneans. Subsequent pairwise tests and similarity profile analysis identified four distinct clusters with similar parasite community structures: (1) pelican and gannet; (2) cormorant; (3) osprey; and (4) tern and both gull species. The mean infracommunity observed species richness differed among the several seabird host species with the highest observed values in pelicans (5.7±0.4) and gannets (5.1±0.4), while the lowest values were seen in herring (0.8±0.7) and laughing (0.4±0.4) gulls. RELATE analyses indicated that the factors of host phylogeny (Rho=0.564, p=0.017), host feeding range (Rho=0.553, p=0.005), and host feeding technique (Rho=0.553, p=0.039) were significant and had similar magnitudes of effect on the structure of observed parasite communities within the several seabird species of this study. Host prey preference was not significant from the RELATE analyses (Rho=0.124, p=0.278), suggesting that preferred prey items of the several seabird hosts had a negligible impact in the structuring of parasite communities. From our results, host phylogeny and host feeding ecology are important driving factors of parasite community composition and structure of these south Florida seabirds, while host prey preference had little influence on parasite communities.

No description available.

Our alarming rate of resource exploitation and its consequences on the environment is fuelling an increase in sustainable energy production around the world. Wind power appears to be a particularly promising energy source relative to its environmental footprint, with the exception of potential negative effects of wind power on birds. Varying results from impact assessments around the world indicate that knowledge of both abiotic and biotic factors, as well as bird behavior and ecology, is required to assess the cumulative impact of any given wind farm on local bird communities. This study aims to assess the cumulative impact of a proposed wind farm on a threatened seabird, the red-throated diver (Gavia stellata), at one of its breeding "hotspots" in Sweden: the Holmöarna islands. Measurements of environmental variables in lakes on Holmöarna are combined with breeding surveys from 2012 to 2015 to assess which environmental variables may be associated with lakes that red-throated divers do or do not breed in, and which variables are correlated with breeding success. These results are combined with a literature review to assess the potential negative effects of the proposed wind farm on the breeding population on Holmöarna. The results show that average breeding success over the survey period was 0.35 fledged young per pair per year. No difference was found in environmental variables between lakes that divers had or had not bred in. Lake area/perimeter ratio and distance to the sea were significantly negatively correlated with breeding success, although distance to the sea was only significant for lakes with at least one successful breeding attempt during the survey period. Based on these correlations, 33 of a total 40 breeding lakes are shown to have relatively high area/perimeter ratios and long distances to the sea, which may pre-dispose divers breeding within them to low breeding success. These lakes are, therefore, identified as being at high-to-moderate risk of increased breeding failure if breeding success is further reduced as a result of external factors, including that of any negative impacts of the proposed wind farm. 31 of the 40 breeding lakes are also within 1 km of the proposed wind turbine sites, which may render red-throated divers breeding within them vulnerable to displacement as a result of wind farm-related disturbance. The literature review highlights the mechanisms that may determine the cumulative impact of the wind farm on red-throated divers in terms of collision mortality, habitat displacement, and barriers to movement. The strong sensitivity of red-throated divers to disturbance is considered to be the most likely driver of any negative effects of the wind farm. In this context, I thus argue the need for a precautionary approach to planning wind power developments in the vicinity of breeding red-throated diver populations.

A poluição por poluentes orgânicos persistentes (POPs) é um tema de considerável importância com relação à conservação de aves marinhas e de seus habitats. A Reserva Biológica do Atol das Rocas (AR) e o Arquipélago de Trindade e Martin Vaz (AT) abrigam grandes populações de aves marinhas no Brasil. As ilhas oceânicas brasileiras podem ser consideradas áreas remotas e preservadas, devido a sua distância do continente. Entretanto, essas regiões também estão sujeitas à influência desses agentes antrópicos oriundos das regiões costeiras. No presente estudo amostras de fígado de seis espécies de aves marinhas do AR e do AT foram analisadas para presença de POPs (PCBs, pesticidas organoclorados e PBDEs) e para isótopos estáveis (13C e 15N). PCBs (3,37 a 189), DDTs (0,5 a 23,1), HCB (0,31 a 12,3) e HCHs (<0,31 a 7,60) foram os compostos predominantes (valores em ng g-1 em massa úmida). A análise de isótopos estáveis contribuiu para esclarecer a relação dos valores de concentração de POPs com os hábitos de forrageio, dieta, distribuição espacial e estágio de vida dos indivíduos em estudo. Correlações significativas entre &#948;15N e os poluentes sugere, em certo grau, uma considerável variação no perfil qualitativo dos PCBs associada ao nível trófico e ao efeito de transporte atmosférico como fonte de introdução desses contaminantes a esses organismos. Os dados de POPs e isótopos mostraram que aves que ocupam posições tróficas maiores tendiam a apresentar também maiores concentrações de contaminantes, assim como perfis qualitativos com predominância de contaminantes mais bioacumulativos. / Pollution persistent organic pollutants (POPs) is an issue of considerable importance with regard to the conservation of seabirds and their habitats. The Rocas Atoll Reserve (AR) and the Trindade e Martin Vaz Archipelago (AT) houses a large population of seabirds in Brazil. Brazilian oceanic islands could be considered as remote and preserved zones, due to its distance from the coast. However, this regions are subjected to the influence of these anthropogenic agents that arising from continental zones. In the present study, liver samples were collected from six seabird species from AR and AT and analysed for the presence of persistent organic pollutants (POPs: PCBs, organochlorine pesticides and PBDEs) and stable isotopes (13C and 15N). PCBs (3.37 to 189), DDTs (0.5 to 23.1), HCB (0.31 to 12.3) and HCHs (<0.31 to 7.60) were the predominant compounds (mean values in ng g-1 wet weight).The stable isotope analysis revealed the relationship of POP levels with foraging, diet, special distribution and living habits of the studied species. Significant correlations found between &#948;15N and POPs suggests, to some extent, that such considerable variation in qualitative PCB levels associated with the trophic level and to the long-range atmospheric transport. POPs level and stable isotope data showed that seabirds that occupy higher trophic positions trend to show the highest POPs levels, as well as, showed the predominance of the most bioaccumulative contaminants on the respective qualitative profiles.

Les échantillons archivés dans les banques d'échantillons de l’environnement (Environmental Specimen Banks en anglais, ESB) sont, parmi les échantillons disponibles pour effectuer des recherches sur l'environnement, les mieux caractérisés géographiquement et issues de longues séries chronologiques. Le mercure (Hg) est un métal lourd hautement toxique et très répandu qui reste l'un des contaminants majeur de l'environnement; les ESB ont joué un rôle de premier plan dans les recherches effectuées sur ce dernier. Ce travail de thèse résume et discute dans un premier temps les modes d’emplois classiques des ESB pour l'étude du mercure dans les écosystèmes aquatiques. Une étude, issue du projet “Seabird Tissue Archival and Monitoring Project” (STAMP), est ainsi présentée pour illustrer comment les œufs d'oiseaux marins peuvent être utilisés pour surveiller les concentrations en Hg environnemental dans les écosystèmes marins subarctique et Arctique. Ce travail présente également un panel d’échantillons archivés dans les ESB du monde entier ; ces échantillons étant estimés comme les plus robustes, fournissent une ressource précieuse pour mener des recherches dans le domaine émergent de la chimie des isotopes stables de mercure. Les signatures isotopiques de fractionnement du mercure sont utilisées pour la répartition des sources et le traçage du cycle biogéochimique du Hg. Ceci est illustré par les résultats de deux études effectuées sur des œufs d'oiseaux marins d’Alaska archivés. Etant donné que les recherches sur les isotopes stables du mercure continuent d'évoluer, les ESB peuvent fournir une source d’échantillons robuste et économique pour élargir et diversifier l'inventaire des mesures des isotopes de Hg, et être utilisées pour développer et tester des hypothèses. Les échantillons archivés dans les ESB sont disponibles à des collaborateurs externes afin d'effectuer des recherches à fort impact, et devraient être pleinement exploités pour répondre aux nouvelles préoccupations environnementales. / The specimens archived in Environmental Specimen Banks (ESBs) are among the longest time-series, most geographically robust, and highest integrity samples available for performing environmental research. Mercury (Hg) is a highly toxic and ubiquitous heavy metal that remains one of the world’s most prominent environmental contaminants, and ESBs have played a prominent role in Hg research. We review and discuss some of the ways in which ESBs have traditionally been used to study Hg in aquatic ecosystems, and show an example of how seabird eggs from the Seabird Tissue Archival and Monitoring Project (STAMP) are used for monitoring environmental Hg concentrations in subarctic and Arctic marine ecosystem. We also highlight some of the most robust sample sets archived in ESBs worldwide, which provide a valuable resource for conducting research in the emerging field of Hg stable isotope chemistry. Signatures of Hg isotope fractionation are used for source apportionment and for tracing biogeochemical cycling of Hg. We present results from two additional studies in Alaska that show how banked seabird eggs can be used for each of these purposes. As the research surrounding Hg stable isotopes continues to mature, ESBs can provide a robust and economical sample archive to expand and diversify the inventory of Hg isotope measurements, and be used to develop and test hypotheses. Samples archived in ESBs are available for request by external collaborators in order to perform high impact research, and should be fully utilized to address emerging environmental concerns.

A poluição por poluentes orgânicos persistentes (POPs) é um tema de considerável importância com relação à conservação de aves marinhas e de seus habitats. A Reserva Biológica do Atol das Rocas (AR) e o Arquipélago de Trindade e Martin Vaz (AT) abrigam grandes populações de aves marinhas no Brasil. As ilhas oceânicas brasileiras podem ser consideradas áreas remotas e preservadas, devido a sua distância do continente. Entretanto, essas regiões também estão sujeitas à influência desses agentes antrópicos oriundos das regiões costeiras. No presente estudo amostras de fígado de seis espécies de aves marinhas do AR e do AT foram analisadas para presença de POPs (PCBs, pesticidas organoclorados e PBDEs) e para isótopos estáveis (13C e 15N). PCBs (3,37 a 189), DDTs (0,5 a 23,1), HCB (0,31 a 12,3) e HCHs (<0,31 a 7,60) foram os compostos predominantes (valores em ng g-1 em massa úmida). A análise de isótopos estáveis contribuiu para esclarecer a relação dos valores de concentração de POPs com os hábitos de forrageio, dieta, distribuição espacial e estágio de vida dos indivíduos em estudo. Correlações significativas entre &#948;15N e os poluentes sugere, em certo grau, uma considerável variação no perfil qualitativo dos PCBs associada ao nível trófico e ao efeito de transporte atmosférico como fonte de introdução desses contaminantes a esses organismos. Os dados de POPs e isótopos mostraram que aves que ocupam posições tróficas maiores tendiam a apresentar também maiores concentrações de contaminantes, assim como perfis qualitativos com predominância de contaminantes mais bioacumulativos. / Pollution persistent organic pollutants (POPs) is an issue of considerable importance with regard to the conservation of seabirds and their habitats. The Rocas Atoll Reserve (AR) and the Trindade e Martin Vaz Archipelago (AT) houses a large population of seabirds in Brazil. Brazilian oceanic islands could be considered as remote and preserved zones, due to its distance from the coast. However, this regions are subjected to the influence of these anthropogenic agents that arising from continental zones. In the present study, liver samples were collected from six seabird species from AR and AT and analysed for the presence of persistent organic pollutants (POPs: PCBs, organochlorine pesticides and PBDEs) and stable isotopes (13C and 15N). PCBs (3.37 to 189), DDTs (0.5 to 23.1), HCB (0.31 to 12.3) and HCHs (<0.31 to 7.60) were the predominant compounds (mean values in ng g-1 wet weight).The stable isotope analysis revealed the relationship of POP levels with foraging, diet, special distribution and living habits of the studied species. Significant correlations found between &#948;15N and POPs suggests, to some extent, that such considerable variation in qualitative PCB levels associated with the trophic level and to the long-range atmospheric transport. POPs level and stable isotope data showed that seabirds that occupy higher trophic positions trend to show the highest POPs levels, as well as, showed the predominance of the most bioaccumulative contaminants on the respective qualitative profiles.

Changes in the marine ecosystem can affect the distribution, survival, and reproductive success of seabirds. Therefore, a better understanding of factors influencing the marine distribution and abundance of seabirds can provide insight into ecological hypotheses and have important conservation implications. Yet at-sea habitat selection by seabirds has received far less attention than have investigations of their breeding biology. I studied the patterns and processes of marine habitat selection by seabirds in nearshore waters of Pacific Rim National Park Reserve, Vancouver Island, British Columbia. The study focused on comparative analyses among five sympatric species: marbled murrelet (Brachyramphus marmoratus), common murre (Uria aalge), rhinoceros auklet (Cerorhinca monocerata), pigeon guillemot (Cepphus columba) and pelagic cormorant (Phalacrocorax pelagicus). I used a multi-scaled and multi-disciplined approach combining shore-based telescope observations, vessel-based surveys, and developed new techniques for mapping nearshore seabird distributions. Patterns of habitat selection were examined through vessel-based surveys and species-habitat modeling. Vessel-based transects are fundamental to studies of seabird ecology, yet standardized protocols often fail to account for detectability biases. Distance-sampling methods were used to quantify seabird detectability along transects and showed extensive variability (20-80% of birds detected) depending on species, year, and observer. Corrected estimates of bird densities were used in habitat selection modeling, which demonstrated inter-specific and inter-annual differences in species-habitat associations. Most species showed distinct partitioning in habitats, particularly with respect to substrate and along gradients of depth and sea-surface temperature/salinity. Thus, environmental variability is a key factor structuring habitat use and coexistence in this community of piscivorous seabirds. Processes of habitat selection were studied through observations of foraging behaviour, estimates of prey availability, and spatial-statistical analysis of seabird distributions. Marbled murrelets increased foraging effort in years and seasons with scarce prey and poor oceanographic conditions and decreased foraging effort at sites with high prey availability. Despite their flexible activity budgets, increased foraging effort was inadequate to buffer reproductive success in a poor prey year, suggesting that prey availability is a limiting factor in habitat use and population growth for murrelets. Theodolite-based mapping studies examined the fine-scale distribution patterns of murrelets and murres. Nearest neighbour spatial statistics tested for competition over foraging space and showed avoidance of murres by murrelets. The results of these studies have implications for the management and conservation of the imperiled marbled murrelet in British Columbia and elsewhere in their range. I demonstrate a clear link between prey availability and consequences for reproductive success. Habitat selection models provide a step towards identifying critical marine habitats which must be protected under the Species at Risk Act. Murrelets show high forage site fidelity and associations with spatially fixed habitat components (beaches), suggesting that marine protected areas may have an important role to play in the conservation, management and recovery of murrelet populations.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / O parasitismo é uma importante força seletiva em populações, assim como a competição e a predação. Os parasitos sanguíneos podem afetar a coloração da plumagem, a seleção sexual e o sucesso reprodutivo em aves. As aves da região Antártica têm sido mencionadas na literatura como livres de hemoparasitos. A Baía do Almirantado, na Ilha Rei George, Península Antártica, é a maior Baía da região, abrigando diferentes espécies de aves durante o período reprodutivo. Dentre elas, estão duas espécies de skuas, as mais frequentes da Antártica, skua-sub-antártica (Catharacta lonnbergi) e skua-polar-do-sul (C. maccormicki) e três espécies de pinguins, pinguim-antártico (Pygoscelis antarctica), pinguim-papua (P. papua) e pinguim-de-adélia (P. adeliae). Skuas e pinguins são aves que se dispersam durante o inverno austral, podendo ser potenciais reservatórios e transmissores de parasitos, embora resultados negativos de hemoparasitos tenham sido encontrados para diversas outras aves marinhas e também para a região Antártica. O objetivo do presente trabalho foi investigar a presença de hemoparasitos em pinguins e skuas antárticos na Baía do Almirantado. Amostras de lâminas de esfregaço sanguíneo e de sangue para análises moleculares de pesquisa de Plasmodium/Haemoproteus foram coletadas em dois períodos reprodutivos, de dezembro de 2010 a março de 2011 e de dezembro de 2011 a fevereiro de 2012. Um total de 185 amostras de aves foram coletadas, incluindo 120 pinguins e 65 skuas. Skuas foram tiveram resultados negativos para hemoparasitos. As três espécies de pinguins foram positivas para Plasmodium/Haemoproteus , via técnica molecular, incluindo dois P. papua,dois P. antarctica etrês P. adeliae. Apenas um indivíduo confirmado positivo pela técnica molecular, pertencente a P. papua, foi positivo utilizando a técnica de esfregaço sanguíneo, com diagnóstico de Plasmodium sp. Não houve diferença significativa entre indivíduos machos e fêmeas das espécies parasitadas, assim como entre adultos e filhotes. As aves parasitadas (n=7), foram categorizadas abaixo do peso (n=5) e acima do peso (n=2). O presente estudo é o primeiro a relatar hemoparasitos na região Antártica e também é o primeiro registro de presença de hemoprotozoários para as três espécies de pinguins analisadas. A ausência de hemoparasitos em aves antárticas tem sido justificada pela ausência de potenciais vetores na região. Portanto, é possível que os pinguins parasitados tenham adquirido a infecção durante a dispersão por ocasião do inverno austral. No entanto, skuas antárticas também são aves migratórias, que podem atingir regiões com potenciais vetores reconhecidos, mas nunca foram diagnosticadas com hemoparasitos, o que foi reforçado pelos resultados negativos do presente estudo. Nesse caso, acredita-se que skuas, podem ter um sistema imune competente ou que a ausência de hemoparasitos nessas aves seja justificada por confinamentos filogenéticos entre parasito-hospedeiro. Entretanto, pouco se sabe sobre a existência de vetores na Antártica, rotas migratórias das aves da região e especificidade parasito-hospedeiro. Os resultados inéditos encontrados no presente estudo devem, portanto, servir como ponto de partida para o entendimento das interações parasito-hospedeiro, de forma a contribuir para a preservação do ambiente antártico. / Parasitism is an important selective pressure in populations, as well as competition and predation. Blood parasites can affect the color of plumage, sexual selection and reproductive success in birds. Antarctic birds have been mentioned in literature absent of blood parasites. Admiralty Bay is located at King George Island, Antarctic Peninsula, and is the largest bay on the region, harboring different avian species during the reproductive period. Among them, are the two most common skuas of Antarctica, the brown-skua (Catharacta lonnbergi) and the south-polar-skua (Catharacta maccormicki), and tree penguins species, the Chinstrap (Pygoscelis antarctica), the Gentoo (P. papua) and the Adelie (P. adeliae). Skuas and penguins are seabirds that migrating during the southern winter, and may be potential reservoirs and transmitters of parasites. However, negative results of blood parasiteshave been found in several seabirds and also to the Antarctic region. The objective of this study was to investigate the presence of blood parasites in Antarctic penguins and skuas at Admiralty Bay. Blood smears and blood samples for molecular analyses to research Plasmodium/Haemoproteuswere collected in two reproductive periods, from December 2010 to March 2011 and from December 2011 to March 2012. A total of 185 bird samples were collected, including 120 penguins and 65 skuas. Skuas were negative for parasites. The tree species of penguins were positives to Plasmodium/Haemoproteusby molecular analysis, including two P. papua, two P. antarctica and tree P. adeliae. Only one positive penguin by molecular technique, a P. papua, was positive in blood smears, diagnosed with Plasmodium sp. There was no significant difference between male and female individuals of the parasitizedspecies, as well as between adults and chicks. Parasitized birds (n = 7) were categorized as underweight (n=5) and overweight (n=2).The present study is the first to report blood parasites in the Antarctic region and is also the first record of the presence of blood protozoa for the three penguin species analyzed. The absence of blood parasites in Antarctic birds has been justified by the absence of potential vectors in the region. Therefore, it is possible that the parasitized penguins acquired infectionwhen they disperse during southern winter. However, antarctic skuas are migratory birds, and they can reach regions with recognized potential vectors, but have never been diagnosed with blood parasites, what was reinforced by data of the present study. In this case, it is believed that skuas may have a competent immune system, or that the absence of these parasites in these birds is justified by phylogenetic constraints between the host-parasite. Nevertheless, little is known about the existence of vectors in the Antarctica, migratory routes of birds in the region and parasite-host specificity. The inedited results found in this study should therefore serve as a starting point to understand the host-parasite interactions, and to contribute to the preservation of the Antarctic environment.