I investigated the relationship between harlequin duck (Histrionicus histrionicus) behavior and lack of recovery from the Exxon Valdez oil spill in Prince William Sound, Alaska. First, I evaluated the hypothesis that harlequin ducks in winter have little flexibility to increase foraging time in response to disturbance because they are constrained to forage during daylight. Eight radio-tagged harlequin ducks wintering in Resurrection Bay, Alaska were monitored for evidence of dive-feeding at night. Each radio-tagged individual was detected during an average of 19.5 of 22 nocturnal monitoring sessions and signal loss indicative of diving behavior was not detected during a total of 780 minutes of signal monitoring. In contrast, the same 8 radio-tagged birds were detected during an average of 9.1 of 12 daytime signal monitoring sessions and signal loss indicated diving behavior during an average of 62 �� 7% of 5-minute daytime monitoring periods (total of 364 minutes of signal monitoring). Thus the harlequin ducks monitored in this study rarely, if ever, fed by diving at night, possibly due to reduced foraging efficiency and (or) increased predation risk at night. This result suggests that harlequin ducks in mid-winter may be severely time-limited in their foraging, especially in northern parts of their winter range. Therefore, subtle changes in energy requirements and (or) time-activity budgets as a result of continued exposure to residual oil from the Exxon Valdez oil spill may affect the ability of harlequin ducks to meet their daily energy requirements. Second, I tested the hypothesis that exposure to crude oil affects time-activity budgets of harlequin ducks. Controlled oil-dosing and plumage-oiling experiments were conducted using adult female harlequin ducks in captivity. I found no evidence that ingestion of weathered Prudhoe Bay crude oil affected the occurrence of feeding activity during 30-minute observation periods, nor was there evidence of effects on time spent feeding. Effects of crude oil ingestion on maintenance activity were detected, but were neither consistent between the 2 years of the study, nor dose-dependent for the 2 doses administered (2 and 20 mL kg����� wk�����), and therefore did not strongly support an oil-dosing effect on maintenance activity. Consequently, these results provided little support for the hypothesis that oil ingestion affects time-activity budgets of captive harlequin ducks, at least for the doses and conditions of captivity used in this study. Plumage-oiling reduced feeding activity in captive harlequin ducks. The estimated probability of feeding during 30-minute observation periods for birds in the high-exposure oiling group (5 mL of crude oil) was 53% less than that of non-oiled controls. Oiled birds exhibited a trend of reduced time feeding with increasing level of external-oiling; this effect was greatest among birds in the high-exposure oiling group, which spent 43% less time feeding than non-oiled birds. Reduced feeding was associated with less time in the water dive-feeding and presumably lower heat loss. Trends in the occurrence of maintenance activity and time spent in maintenance activity for birds in the high-exposure treatment suggested plumage-oiling increased maintenance activity, but results were not conclusive. The behavioral changes associated with plumage-oiling in captivity would likely reduce fitness in the wild, where a high proportion of time must be spent in the water feeding. If residual Exxon Valdez oil sequestered in beach sediments enters the water column where it may be encountered by harlequin ducks, external exposure may lead to reduced feeding activity. This, in turn, may compromise survival, particularly during mid-winter when the time available for diurnal foraging is low and maintenance energy requirements are high. / Graduation date: 2004

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

Resumo: Diretamente sob influência do Canal de São Sebastião - onde está estabelecido o maior terminal petrolífero do Brasil e ocorre intensa movimentação de petroleiros -, a faixa litorânea do município de Ilhabela-SP é freqüentemente impactada por vazamentos de óleo. Daí, sua condição de ser, entre todos os municípios do litoral-norte paulista, aquele que mais é impactado por vazamentos. Trata-se de área com alta relevância ecológica por conter ricos e diversificados recursos biológicos, bem como por apresentar significativa atividade sócio-econômica que envolve o turismo e a pesca. Este estudo apresenta, em escala de detalhe (1:10.000 a 1:25.000), um conjunto de vinte e quatro cartas SAO de caráter operacional e uma de caráter tática para a face oeste da Ilha de São Sebastião. Contempla, ainda, mapas temáticos, quadros de recursos visuais e listagem das espécies encontradas no arquipélago. A elaboração de tais cartas seguiu as recomendações do MMA-Brasil. Ao indicar as áreas historicamente mais atingidas por vazamento de óleo e definir áreas que requerem proteção especial e faixas de sacrifício, este estudo passa, no seu conjunto, a constituir valioso documento a ser usado em planos de contingência e emergência referentes ao arquipélago. / Abstract: Directly influenced by the São Sebastião Channel - where the biggest petroliferous terminal is installed and where occurs the highest numbers of tankers coming alongside - the coast side of Ilha Bela city - SP is frequently damaged by oil spills. Therefore it is considered the most 'harmed by leaking' city in the coast. It is a high ecologically relevant area for its risks and diversified biological resources, as well as for its significant socio-economical activities that involves tourism and fishing. This article shows, in detail (1:10.000 to 1:25.000) a set of twenty-three ESI maps and also a tactical one, facing the west side of São Sebastião Island. It also shows thematic maps, visual resources and a species list from the archipelago. The process to create those maps was strict to the Brazilian Environmental Ministry recommendations. As it indicates the historical areas that were damaged the most for oil spills and as it defines the areas that require special attention and sacrifice areas, it has become, as a whole, a valuable document to be used in emergency and contingency plans for the archipelago. / Orientador: Dimas Dias-Brito / Coorientador: João Carlos Carvalho Milanelli / Banca: Décio Luis Semensatto Junior / Banca: Paulina Setti Riedel / v. 2 - mapas temáticos, quadros descritivos de recursos visuais, listagens de espécies da fauna / Mestre

Since no local crude oil sources exist, every drop of petroleum consumed in Oregon originates from outside sources and is distributed multi-modally to consumers. As population continues to increase and oil sources dwindle, this reliance may add financial and environmental risks to Oregonian' s quality of life. This paper examines Oregon's oil distribution system, and analyzes the risks oil movements pose in the state. A comprehensive understanding of oil distribution in Oregon can best be gained geographically. Pipelines, ships, barges, railroads and trucks play different roles in this system, yet data for these transport modes are maintained by different groups and unstandardized. Therefore, the data must be normalized to present a map of how oil is being moved around the state. This study sets all levels to a barrels (42 U.S. gallons) per month (assumed 30 days) standard. Oil's role in the economy of our state, most noticeably in the sale of motor gasoline, creates different types of risk. The most obvious risk results from transportation, and Oregon is plagued daily by unintended releases. A second type of risk, supply risk, exists because of our reliance on the petroleum networks of Alaska, Washington and California, and was evident during the 1974 oil embargo. Lastly, economic risk should theoretically be present since Oregon is a downstream consumer from adjacent states. During times of shortages, Oregon should be at the mercy of those who provide its supply. The data do not support this, but suggest that oil is purely a global commodity, and price and supply are determined worldwide in response to typical marketing forces. The distribution systems detailed herein are dynamic, and outside forces such as the proposed export of Alaskan crude oil, the increased exploration of offshore oil fields, and the development of a cross-Cascades pipeline may alter this scheme. Oregonians can ensure the most effective petroleum distribution systems only by understanding them and their associated risks.

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O correto é Sumário. on 2018-06-06T19:29:32Z (GMT) / Submitted by Alexandre Magnum Leme (alexandremagnumleme@gmail.com) on 2018-06-06T19:48:44Z No. of bitstreams: 1 Dissertação - Alexandre Leme.pdf: 17588860 bytes, checksum: f14b7589595476ddfa37ecc37df9836f (MD5) / Rejected by Ana Paula Santulo Custódio de Medeiros null (asantulo@rc.unesp.br), reason: - Na folha de aprovação está faltando o conceito: favor solicitar à Seção de Pós-Graduação on 2018-06-07T11:21:36Z (GMT) / Submitted by Alexandre Magnum Leme (alexandremagnumleme@gmail.com) on 2018-06-07T12:18:07Z No. of bitstreams: 1 Dissertação - Alexandre Leme.pdf: 17592673 bytes, checksum: 808ca0e115bf662c3378ae7dbfa632a3 (MD5) / Approved for entry into archive by Ana Paula Santulo Custódio de Medeiros null (asantulo@rc.unesp.br) on 2018-06-07T17:46:41Z (GMT) No. of bitstreams: 1 leme_am_me_rcla.pdf: 17579022 bytes, checksum: fa6b94de2f7751d34757bd7db7c0a590 (MD5) / Made available in DSpace on 2018-06-07T17:46:41Z (GMT). No. of bitstreams: 1 leme_am_me_rcla.pdf: 17579022 bytes, checksum: fa6b94de2f7751d34757bd7db7c0a590 (MD5) Previous issue date: 2018-05-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / No Brasil, a rodovia se apresenta como um dos modais mais utilizados para o transporte de derivados do Petróleo, consequente a esse fato os espaços ambientais adjacentes a rodovias se destacam como áreas importantes para mapeamentos de sensibilidade ambiental a derrames de óleo. Dados da CETESB (2009) apontam que no período de 1978 a 2009 cerca de 40% dos acidentes ambientais envolvendo produtos perigosos no Estado de São Paulo foram referentes ao transporte rodoviário. As Cartas de Sensibilidade Ambiental ao Óleo (Cartas SAO) apresentam o índice de sensibilidade ambiental, obtido a partir de características do meio físico e representado num intervalo de 1 a 10, além de informações bióticas e socioeconômicas, representadas na forma de ícones predefinidos. Estas cartas são importante ferramenta de apoio técnico gerencial para a tomada de decisão no planejamento de ações de emergência, em casos de acidentes envolvendo óleo e são amplamente utilizadas em áreas costeiras, onde são produzidas a partir de adaptações de metodologia elaborada pela National Oceanic and Atmospheric Administration (NOAA). Não existe, porém, uma padronização destas cartas para ambientes terrestres. A presente pesquisa propõe um índice de sensibilidade terrestre denominado índice socioambiental a derrames de óleo em rodovias (ISS), por contemplar fatores físicos, bióticos e socioeconômicos em sua composição. O presente trabalho realiza também uma comparação entre o resultado do mapeamento realizado com este índice e aquele ancorado somente no meio físico, nos moldes do que é efetuado para ambientes costeiros, como contribuição para a padronização futura das Cartas SAO em ambientes terrestres. Para a elaboração do índice proposto, utilizou-se primeiramente a técnica de Compartimentação Fisiográfica, por meio da qual são estabelecidas áreas com características homogêneas, para posterior classificação da sensibilidade ao óleo. O processo de compartimentação se deu por meio de fotointerpretação de imagens orbitais SPOT 5 e trabalho de campo, o que propiciou a delimitação de 13 Unidades Básicas de Compartimentação – UBCs, classificadas de acordo com cinco parâmetros físicos: declividade, textura e espessura do perfil de alteração do solo , profundidade do nível d’água e densidade de drenagem e cinco parâmetros socioambientais: existência de unidades de Conservação, área ocupada por fragmentos florestais, uso e ocupação do solo, IDHM dos municípios e vulnerabilidade da rodovia. Foram estabelecidos pesos variando de 1 a 3 para cada parâmetro e realizada uma álgebra de mapas no software ArcGIS 10.2.2 (ESRI), para a elaboração das duas cartas de sensibilidade. Na primeira carta, os índices de sensibilidade foram obtidos somente a partir das características do meio físico (IST), enquanto a segunda incorporou na elaboração do índice as características bióticas e socioeconômicas (ISS). Como resultado, a área de estudo apresentou uma maior concentração de índices elevados e intermediários de sensibilidade para o IST e concentração de valores de média a baixa sensibilidade para o ISS. Conclui-se que o índice de sensibilidade ambiental ao óleo utilizando os fatores bióticos e socioeconômicas (ISS) é uma representação mais realista das características do meio terrestre, com produção rápida e objetiva e que permite a aplicação em ambientes similares, embora haja necessidade de atualização constante, por incluir características dinâmicas, como as socioeconômicas. / In Brazil, the highway is one of the most used modalities for the transport of petroleum derivatives and because of that the space adjacent to highways stands out as important area for environmental sensitivity mapping to oil spills. Data from CETESB (2009) indicate that from 1978 to 2009, about 40% of the accidents involving dangerous products in the State of São Paulo were related to the road transport. The Environmental Sensitivity Maps for Oil Spills present the environmental sensitivity index obtained from characteristics of the physical environment and represented in a range from 1 to 10, as well as biotic and socioeconomic information, represented as predefined icons. These maps are an important tool for decisionmaking for emergency response in case of accidents involving oil and are widely used in coastal areas, where they are produced based on a methodology designed by the National Oceanic and Atmospheric Administration (NOAA). There is, however, no standardization for the terrestrial environment. This research proposes a terrestrial sensitivity index called socio environmental index to oil spills on highways (ISS), considering physical, biotic and socioeconomic factors in its composition. The present research also compares the result of the mapping performed with this index and that anchored only in the physical environment, as applied for coastal areas, as a contribution to the future standardization of the SAO mapping for terrestrial environment. For the proposed index, the Physiographic Compartmentalization technique was applied, in order to establish homogeneous areas, for later classification of their oil sensitivity. This process was performed by the photointerpretation of SPOT 5 images and field work, and 13 Basic Compartmentation Units – UBCs were delimitated and classified according to five physical parameters: slope, texture and thickness of the soil profile, water depth and drainage density and also five socio-environmental parameters: existence of conservation units, area of forest fragments, land cover and landuse, municipalitie´s IDH, and highway vulnerability. Weights ranging from 1 to 3 were established for each parameter and a map algebra was performed in the ArcGIS 10.2.2 software (ESRI), to produce the two sensitivity maps. In the first map, the sensitivity indexes were obtained only from the characteristics of the physical environment (IST), while the second incorporated the biotic and socioeconomic characteristics (ISS) into the index. As a result, the study area presented a higher concentration of high and intermediate sensitivity index for the IST and concentration of medium to low sensitivity index for the ISS. It is concluded that the environmental sensitivity index to oil using biotic and socioeconomic factors (ISS) is a more realistic representation of the terrestrial environment, with rapid and objective production and allows the application in similar environments, although there is a need for updating, because it includes dynamic characteristics, such as socioeconomic ones.

Made available in DSpace on 2014-06-11T19:26:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-07-12Bitstream added on 2014-06-13T20:33:55Z : No. of bitstreams: 1 lima_mv_me_rcla.pdf: 3594666 bytes, checksum: 016e725489200fc73cd62ffd1a9390eb (MD5) / Agência Nacional do Petróleo, Gás Natural e Biocombustíveis (ANP) / Diretamente sob influência do Canal de São Sebastião - onde está estabelecido o maior terminal petrolífero do Brasil e ocorre intensa movimentação de petroleiros -, a faixa litorânea do município de Ilhabela-SP é freqüentemente impactada por vazamentos de óleo. Daí, sua condição de ser, entre todos os municípios do litoral-norte paulista, aquele que mais é impactado por vazamentos. Trata-se de área com alta relevância ecológica por conter ricos e diversificados recursos biológicos, bem como por apresentar significativa atividade sócio-econômica que envolve o turismo e a pesca. Este estudo apresenta, em escala de detalhe (1:10.000 a 1:25.000), um conjunto de vinte e quatro cartas SAO de caráter operacional e uma de caráter tática para a face oeste da Ilha de São Sebastião. Contempla, ainda, mapas temáticos, quadros de recursos visuais e listagem das espécies encontradas no arquipélago. A elaboração de tais cartas seguiu as recomendações do MMA-Brasil. Ao indicar as áreas historicamente mais atingidas por vazamento de óleo e definir áreas que requerem proteção especial e faixas de sacrifício, este estudo passa, no seu conjunto, a constituir valioso documento a ser usado em planos de contingência e emergência referentes ao arquipélago. / Directly influenced by the São Sebastião Channel - where the biggest petroliferous terminal is installed and where occurs the highest numbers of tankers coming alongside - the coast side of Ilha Bela city - SP is frequently damaged by oil spills. Therefore it is considered the most 'harmed by leaking' city in the coast. It is a high ecologically relevant area for its risks and diversified biological resources, as well as for its significant socio-economical activities that involves tourism and fishing. This article shows, in detail (1:10.000 to 1:25.000) a set of twenty-three ESI maps and also a tactical one, facing the west side of São Sebastião Island. It also shows thematic maps, visual resources and a species list from the archipelago. The process to create those maps was strict to the Brazilian Environmental Ministry recommendations. As it indicates the historical areas that were damaged the most for oil spills and as it defines the areas that require special attention and sacrifice areas, it has become, as a whole, a valuable document to be used in emergency and contingency plans for the archipelago.

Oil spills have long been recognized as a significant threat to wildlife. Historically, mortality estimates have served as the basis for assessing impact to natural resources. However, these mortality estimates alone neglect the more wide-spread impact of oil spills on wildlife including birds, many of which may not immediately succumb to exposure, but instead suffer sublethal injury that may negatively affect physiological homeostasis, reproduction, and long-term survival. Therefore, there is a need to improve our understanding of the risk of exposure and effect of sublethal oiling during damage assessments. In this dissertation I evaluated the extent of sublethal oil exposure in the immediate aftermath of the Deepwater Horizon spill on American oystercatchers (Haematopus palliatus), black skimmers (Rynchops niger), brown pelicans (Pelecanus occidentalis), clapper rails (Rallus crepitans), and seaside sparrows (Ammodramus maritimus) through both visual evaluation of and under the application of ultraviolet light to individual birds potentially exposed to oil. I found that there were many individual birds with modest oil exposure, demonstrating that more birds are exposed to oil than are accounted for by mortality estimates. Additionally, I developed a field-adapted technique using an in vitro method in brown pelicans that was effective in determining oxidative hematologic injury as measured by a suite of parameters including a reduction in circulating erythrocytes and hemoglobin, formation of Heinz bodies, and an increase in reticulocytes, in birds exposed to oil. I then applied this suite of parameters to individual birds affected in the aftermath of the Deepwater Horizon spill, and found that birds with modest visible or UV-detectible oil exposure suffer hematologic injury, a quantifiable adverse sublethal effect of modest oil exposure. Finally, I used an experimental approach to evaluate the pathologic effects of crude oil exposure in zebra finches (Taeniopygia guttata), evaluating the same suite of hematologic parameters as well as gross pathology, histopathology, and electron microscopy. This controlled study provided evidence that there may be significant variability in the response of birds to oil exposure that may be attributable to species-specific sensitivity and/or other factors such as the use of dispersants after oil spills. Collectively, this body of work demonstrated that many more birds are exposed to oil during spill events than are accounted for by mortality estimates alone, and that these birds can suffer quantifiable sublethal hematologic injury. The ability to accurately assess the extent of exposure and hematologic damage caused by oil spills is critical to determine the appropriate approach to management needed to offset impacts to fisheries, wildlife, habitats, and economic resources impacted by oil spills. / Doctor of Philosophy / Fossil fuels are the world's primary energy source and are an important part of everyday life. Our reliance on petroleum requires extraction, transportation, storage, and refinement of millions of gallons of crude oil each day. As an unintended consequence, some of this oil is inadvertently spilled into the environment, and these oil spills have long been recognized as a threat to wildlife. Assessing the impact of oil spills on wildlife is a major concern to industries, government, and the general public. Historically, mortality estimates have served as the basis for assessing impact to natural resources. However, these mortality estimates alone neglect the more wide-spread impact of oil spills on wildlife including birds, many of which may not immediately succumb to exposure, but instead suffer sublethal physiologic injury that negatively affects physiology, reproduction, and long-term survival. Therefore, there is a need to improve our understanding of the risk of exposure and effects of sublethal oiling during damage assessments. In this dissertation, I evaluated the extent of sublethal exposure to oil from The Deepwater Horizon spill for several species of birds through both visual evaluation of and under the application of ultraviolet light. This demonstrated that many more birds are affected by oil exposure than are accounted for by mortality estimates. Additionally, I developed a field-adapted technique in a controlled setting that is effective in determining oxidative injury to red blood cells in birds exposed to oil, and applied this approach to several species in the field during the aftermath of the Deepwater Horizon spill. Finally, I used an experimental approach to evaluate the extent of pathologic effects of Deepwater Horizon crude oil exposure in individuals under controlled dosages. The ability to accurately assess the extent of damage caused by oil spills is critical to determine the appropriate approach to management needed to offset impacts to fisheries, wildlife, habitats, and economic resources impacted by oil spills.

The pigeon guillemot (Cepphus columba) population in Prince William Sound has failed to recover from declines that occurred both before and after the Exxon Valdez Oil Spill (EVOS). Post-spill studies of pigeon guillemot breeding biology have identified three potential factors limiting recovery: (1) predation on eggs and nestlings; (2) declines in the proportion of high-lipid, schooling forage fish (sand lance [Ammodytes hexapterus], herring [Clupea pallasi], and capelin [Mallotus villosus]) in the diet; and (3) continued exposure to residual oil from the spill. This laboratory study with captive-reared pigeon guillemots at the Alaska SeaLife Center investigated two aspects of the species' biology that are relevant to restoration in the aftermath of EVOS. First, we investigated the role of dietary factors (prey type, quantity of food consumed, dietary fat content, and energy intake rate) in limiting the growth, development, survival, and fledging condition of nestling pigeon guillemots. The objective was to understand how changes in prey availability and prey quality might affect pigeon guillemot productivity. Second, we fed nestlings sublethal doses of weathered Prudhoe Bay crude oil (PBCO) and then measured several potential biomarkers of effects from this pollutant. These dose-response experiments were designed to (1) better understand the impact on nestling guillemots of petroleum hydrocarbons in food, (2) calibrate existing and potential biomarkers of exposure to PBCO in pigeon guillemots in a controlled, laboratory setting, and (3) develop better nondestructive biomarkers of exposure to PBCO in pigeon guillemots in particular, and seabirds in general. Results of feeding experiments indicated that most variation in nestling growth rates could be explained by variation in daily energy intake. The type of forage fish consumed, the lipid or protein content of the forage fish, and even the quantity of food consumed daily did not have as strong an effect on nestling guillemot growth as did daily energy intake. The metabolic efficiency and growth performance of nestling guillemots was not enhanced on high-lipid diets, contrary to results with nestlings of some other seabird species. Instead, structural growth (wing length) in nestling guillemots was somewhat stunted on high-lipid diets. These attributes of guillemot nutritional requirements are associated with the guillemots' nearshore foraging niche and high food provisioning rates to nestlings. The average lipid content of sand lance, juvenile herring, and capelin may represent the optimal dietary lipid content for nestling pigeon guillemots. This study supports the hypothesis that guillemot productivity is limited by the availability of these forage fishes through effects on energy provisioning rates to nestling guillemots. Consequently, recovery of pigeon guillemot populations injured by EVOS is likely linked to recovery of these key forage fish stocks. Results of the oil-dosing experiments indicated that nestling guillemots are resistant to small doses of weathered PBCO in their food. No nestlings died or suffered noticeable health effects following dosing. The high dose in this study (0.5 ml kg����� day�����) was sufficient to induce hepatic cytochrome P450A1 (a liver enzyme indicative of contaminant exposure), but growth rate, fledging mass, and blood chemistry were largely unaffected. None of the 12 plasma or hematological markers examined responded in a dose-dependent manner to ingestion of weathered PBCO, except lactate dehydrogenase (LDH). Although baseline stress hormone (corticosterone) levels were not different between oil-dosed and control nestlings, a standardized acute stress protocol revealed that corticosterone was more elevated during stress for oiled nestlings compared to controls. Although we were not successful in identifying a noninvasive biomarker (e.g., growth) or a blood biomarker (e.g., haptoglobin) of crude oil exposure in nestlings, we were able to confirm that levels of hepatic cytochrome P4SO1AI and corticosterone during stress were elevated by the sublethal doses administered during our experiments. Based on this and other studies, it is unlikely that the failure of pigeon guillemots to recover from EVOS is due to effects on nestling health of residual oil in food. / Graduation date: 2003

The 2010 Deepwater Horizon (DWH) oil spill resulted in a large release of polycyclic aromatic hydrocarbons (PAH) into the Gulf of Mexico. PAH can interact with ultraviolet radiation (UV) resulting in increased toxicity, particularly to early lifestage organisms. The goal of this research was to determine the sensitivity of fiddler crab larvae (Uca longisignalis) to photo-induced toxicity following exposure to Deepwater Horizon spill oil in support of the DWH Natural Resource Damage Assessment. Five replicate dishes each containing 20 larvae, were exposed to one of three UV treatments (10%, 50%, and 100% ambient natural sunlight) and one of five dilutions of water accommodated fractions of two naturally weathered source oils. A dose dependent effect of PAH and UV on larval mortality was observed. Mortality was markedly higher in PAH treatments that included co-exposure to more intense UV light. PAH treatments under low intensity sunlight had relatively high survival. These data demonstrate the importance of considering combined effects of non-chemical (i.e. UV exposure) and chemical stressors and the potential for photo-induced effects after exposure to PAH following the Deepwater Horizon spill.