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The BP MC252 well failure in the Gulf of Mexico, April 2010 caused concern for crude oil and polycyclic aromatic hydrocarbon (PAHs) exposure along the sandy beaches of the Florida Panhandle. We began collections of Coquina clams (Donax spp.) from the surf zone of Florida Panhandle beaches to monitor PAH contamination to compliment analysis of surf zone sand samples. These clams had higher levels of PAHs relative to ambient sand, and this allowed us to continue to monitor PAH levels after sand concentrations fell below limits of detection. PAH levels in the Coquina tissues were highly variable, perhaps indicative of the heterogeneous distribution of oil and tar on the beaches and exposure to tar particles. Overall, PAH levels decreased continuously in both sand and Coquina tissues, reaching limits of detection within one and two years respectively after oil landed on Florida Panhandle beaches. Our work suggests these surf zone molluscs may be used to monitor pollutant exposure along high energy sandy beach shorelines., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Illegal discharge of waste oil from ships is a major source of mortality for seabirds globally. Using linear and log-linear regression, we explored the relationship between detection rates of marine oily discharges and surveillance effort at different time scales, based on data collected in the Canadian Pacific Ocean by the National Aerial Surveillance Program (NASP) from 1997 to 2006. We introduce an approach for quantifying reductions in discharge rates with increased surveillance while controlling appropriately for surveillance effort, as standard linear correction for effort can introduce considerable bias. Despite low probabilities of detection (0.088-1.1%), we found evidence for reduced discharge rates with increasing surveillance effort for data summarized monthly and bimonthly in region A, which is closest to the NASP base airport. Using residuals derived from the best-fit log-linear models, we found detected discharge rates declined annually (-[0.070 spills/month]×year)., (Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.)

This paper examines the use of exploratory spatial analysis for identifying hotspots of shipping-based oil pollution in the Pacific Region of Canada's Exclusive Economic Zone. It makes use of data collected from fiscal years 1997/1998 to 2005/2006 by the National Aerial Surveillance Program, the primary tool for monitoring and enforcing the provisions imposed by MARPOL 73/78. First, we present oil spill data as points in a "dot map" relative to coastlines, harbors and the aerial surveillance distribution. Then, we explore the intensity of oil spill events using the Quadrat Count method, and the Kernel Density Estimation methods with both fixed and adaptive bandwidths. We found that oil spill hotspots where more clearly defined using Kernel Density Estimation with an adaptive bandwidth, probably because of the "clustered" distribution of oil spill occurrences. Finally, we discuss the importance of standardizing oil spill data by controlling for surveillance effort to provide a better understanding of the distribution of illegal oil spills, and how these results can ultimately benefit a monitoring program.