Associate in Research
Marine Geospatial Ecology Lab
Duke University Marine Lab
135 Duke Marine Lab Road
Beaufort, NC 28516 Telephone: 252-504-7640 Fax: 252-504-7648
Kot, C.Y., E. Fujioka, L.J. Hazen, B.D. Best, A.J. Read, and P.N. Halpin. 2010. Spatio-temporal gap analysis of OBIS-SEAMAP project data: Assessment and way forward. PLoS ONE 5(9): e12990. doi:10.1371/journal.pone.0012990 [Abstract] [PDF][Supplemental] [Online Link]
Wallace, B.P., R.L. Lewison, S. McDonald, T. McDonald, C.Y. Kot, S. Kelez, R.K. Bjorkland, E.M. Finkbeiner, S. Helmbrecht, and L.B. Crowder. 2010. Global patterns of marine turtle bycatch. Conservation Letters 3(3): 131-142. doi:10.1111/j.1755-263X.2010.00105.x [Abstract] [PDF] [Media Mentions]
Kot, C.Y., A.M. Boustany, and P.N. Halpin. 2010. Temporal patterns of target catch and sea turtle bycatch in the U.S. Atlantic pelagic longline fishing fleet. Canadian Journal of Fisheries and Aquatic Sciences 67(1): 42-57. doi:10.1139/F09-160 [Abstract] [Online Link] [PDF]
Halpin, P.N., A.J. Read, E. Fujioka, B.D. Best, B. Donnelly, L.J. Hazen, C. Kot, K. Urian, E. LaBrecque, A. DiMatteo, J. Cleary, C. Good, L.B. Crowder, and K.D. Hyrenbach. 2009. OBIS-SEAMAP: The world data center for marine mammal, sea bird and sea turtle distributions. Oceanography 22(2):96-107. [Abstract] [Online PDF]
Dunn, D.C., C.Y. Kot, and P.N. Halpin. 2008. A comparison of methods to spatially represent pelagic
longline fishing effort in catch and bycatch studies. Fisheries Research 92(2-3): 268-276. doi:10.1016/j.fishres.2008.01.006.
[Abstract] [Online PDF]
Technical Reports and Articles:
Pittman, S., B. Costa, C. Kot, D. Wiley, and R.D. Kenney. 2006. Chapter 5 - Cetacean distribution and diversity, pp. 265-325.
In: NOAA National Centers for Coastal Ocean Science (NCCOS), An Ecological Characterization of the Stellwagen Bank National Marine Sanctuary Region: Oceanographic, Biogeographic, and Contaminants Assessment. Prepared by NCCOS's Biogeography Team in cooperation with the National Marine Sanctuary Program. Silver Spring, MD. NOAA Technical Memorandum NOS NCCOS 45. 356 pp.
[Abstract] [Chapter PDF] [Full Report PDF] [Website]
Kot, C.Y. and E. Fujioka. 2009. OBIS-SEAMAP - a spatially and temporally interactive marine megavertebrates archive. The Seabird Group Newsletter 111:9-11. [PDF]
Master's Thesis:
Moy, C.Y. 2004. Development and evaluation of an estuarine biotic integrity index for South Carolina tidal creeks. Master's Thesis, University of Charleston, Charleston, South Carolina
[Abstract] [PDF][Conference Abstract]
Select Presentations:
Hazen, L.J., E. Fujioka, P.N. Halpin, A.J. Read, B.D. Best, C. Kot , K. Urian, B. Donnelly, A. DiMatteo, E.A. LaBrecque, M. Soldevilla, and C. Good. 2009. OBIS-SEAMAP: an online portal for marine mammal observations. Presented at the Society for Marine Mammalogy Biennial Conference on the Biology of Marine Mammals, October 12-16, 2009, Quebec City, Canada [Abstract] [PDF]
Zydelis, R., P.N. Halpin, A.J. Read, B.D. Best, E. Fujioka, L.J. Hazen, and C. Kot. 2008. OBIS-SEAMAP as a Toolbox for Managing Sea Duck Tracking Data. Presented at the 3rd North American Sea Duck Conference, November 10-14, 2008, Quebec City, Canada. [Abstract] [PDF]
Hazen, L., E. Fujioka, P.N. Halpin, A.J. Read, B.D. Best, B. Donnelly, C. Kot, and K. Urian. 2008. OBIS-SEAMAP Version 2.0: Improvements in Mapping Marine Megavertebrates. Presented at the Southeast and Mid-Atlantic Marine Mammal Symposium, March 28-30, 2008, Charleston, South Carolina. [Abstract] [PDF]
Halpin, P., A.M. Boustany, J. Roberts, D. Dunn, and C. Kot. 2008. New innovations to reduce fisheries bycatch. Presented at the American Association for the Advancement of Science, February 14-18, 2008, Boston, Massachusetts.
Bjorkland, R., D. Dunn, L. Crowder, K. Eckert, S. Eckert, C. Kot, S. McDonald, and A. Boustany. 2008. A summary review of sea turtle bycatch in the wider Caribbean. Presented at the 28th Sea Turtle Symposium, January 19-26, 2008, Loreto, Baja California Sur, Mexico. [Abstract] [PDF]
Moore, J.E., L. Crowder, R. Lewison, A. Read, T. Cox, W. J. Nicols, P. Halpin, C. Safina, B. Wallace, R. Zydelis, M. Sims, R. Bjorkland, S. Kelez, C. Kot, and D. Dunn. 2007. Project GloBAL: assessing bycatch of marine megafauna in the world's fisheries. Presented at West African Talks on Cetaceans and their Habitats (WATCH), under the Convention on Migratory Species (CMS), October 16-20, 2007, Tenerife, Spain.
Buja, K.R. and C.Y. Kot. 2007. A GIS management tool to reduce sea turtle bycatch. Presented at the ESRI User Conference, June 18-22, 2007, San Diego, California.
[Abstract] [Conference Abstract]
Costa, B., T. Battista, S. Pittman, R. Clark, C. Kot, K. Eschelbach, F. Huettmann, and I. Hartwell. 2007. An ecological characterization of the Gulf of Maine region. Presented at the ESRI User Conference, June 18-22, 2007, San Diego, California.
[Abstract] [Conference Abstract]
Kot, C.Y., D.C. Dunn, and P.N. Halpin 2007. Alternative methods to spatially distribute fishing effort within the Hawaiian longline fishery and corresponding effects on the calculation of bycatch rates. Presented at the Coastal GeoTools Conference, March 5-8, 2007, Myrtle Beach, South Carolina.
[Abstract] [PDF] [Conference Abstract]
Dunn, D.C., C.Y. Kot, and P.N. Halpin. 2007. Alternative methods to spatially distribute fishing effort within the Hawaiian longline fishery and corresponding effects on the calculation of bycatch rates. Presented at the 27th Annual Sea Turtle Symposium, February 22-28, 2007, Myrtle Beach, South Carolina.
[Abstract] [PDF] [Conference Abstract]
Workshop Participation:
South Atlantic Ecosystem Tools and Model Development Workshop. South Atlantic Fishery Management Council, Duke University, Nicholas School of the Environment and Earth Sciences and Marine Sciences, University of North Carolina, Chapel Hill, February 21-22, 2008, held at Duke University Marine Lab, Beaufort, NC. [PDF]
North Carolina Estuarine Shoreline Mapping (ESM) Summit. North Carolina Division of Coastal Management and North Carolina National Estuarine Research Reserve's Coastal Training Program, December 4-5, 2007, held at the National Oceanic and Atmospheric Administration, Beaufort, NC. [PDF]
2006 Protected Species Stock Assessment Improvement Plan (SAIP) Tier III Workshop. NOAA Fisheries, March 7-10, 2006, held at the National Oceanic Atmospheric Administration, Silver Spring, MD. [PDF] [Website]
GIS Tools Supporting Ecosystem Approaches to Management Workshop. NOAA Fisheries and NOS/NCCOS Center for Coastal Monitoring and Assessment, held at the National Oceanic and Atmospheric and Administration's Coastal Services Center, September 8-10, 2004, Charleston, SC. [PDF] [Website]
The OBIS-SEAMAP project has acquired and served high-quality marine mammal, seabird, and sea turtle data to the public since its inception in 2002. As data accumulated, spatial and temporal biases resulted and a comprehensive gap analysis was needed in order to assess coverage to direct data acquisition for the OBIS-SEAMAP project and for taxa researchers should true gaps in knowledge exist. All datasets published on OBIS-SEAMAP up to February 2009 were summarized spatially and temporally. Seabirds comprised the greatest number of records, compared to the other two taxa, and most records were from shipboard surveys, compared to the other three platforms. Many of the point observations and polyline tracklines were located in northern and central Atlantic and the northeastern and central-eastern Pacific. The Southern Hemisphere generally had the lowest representation of data, with the least number of records in the southern Atlantic and western Pacific regions. Temporally, records of observations for all taxa were the lowest in fall although the number of animals sighted was lowest in the winter. Oceanographic coverage of observations varied by platform for each taxa, which showed that using two or more platforms represented habitat ranges better than using only one alone. Accessible and published datasets not already incorporated do exist within spatial and temporal gaps identified. Other related open-source data portals also contain data that fill gaps, emphasizing the importance of dedicated data exchange. Temporal and spatial gaps were mostly a result of data acquisition effort, development of regional partnerships and collaborations, and ease of field data collection. Future directions should include fostering partnerships with researchers in the Southern Hemisphere while targeting datasets containing species with limited representation. These results can facilitate prioritizing datasets needed to be represented and for planning research for true gaps in space and time.
Global patterns of marine turtle bycatch
Bryan P. Wallace, Rebecca L. Lewison, Sara McDonald, Trey McDonald, Connie Y. Kot, Shaleyla Kelez, Rhema K. Bjorkland, Elena M. Finkbeiner, S'rai Helmbrecht, Larry B. Crowder
Fisheries bycatch is a primary driver of population declines in several species ofmarine megafauna (e.g., elasmobranchs, mammals, seabirds, turtles). Characterizing the global bycatch seascape using data on bycatch rates across fisheries is essential for highlighting conservation priorities. We compiled a comprehensive database of reported data on marine turtle bycatch in gillnet, longline, and trawl fisheries worldwide from 1990 to 2008. The total reported global
marine turtle bycatch was ~85,000 turtles, but due to the small percentage of fishing effort observed and reported (typically <1% of total fleets), and to a global lack of bycatch information from small-scale fisheries, this likely underestimates
the true total by at least two orders of magnitude. Our synthesis also highlights an apparently universal pattern across fishing gears and regions where high bycatch rates were associated with low observed effort, which emphasizes
the need for strategic bycatch data collection and reporting. This study provides the first global perspective of fisheries bycatch for marine turtles and highlights region-gear combinations that warrant urgent conservation action (e.g., gillnets, longlines, and trawls in the Mediterranean Sea and eastern Pacific Ocean) and region-gear combinations in need of enhanced observation and reporting efforts (e.g., eastern Indian Ocean gillnets, West African trawls).
Sea turtle bycatch in pelagic longline fishing gear is an ongoing threat to the conservation of sea turtle populations. However, these bycatch events do not occur uniformly in space or time. Leatherback (Dermochelys coriacea) and loggerhead (Caretta caretta) bycatch rates reported in large fishing regions exhibited different degrees of interannual variability. Target catch and sea turtle bycatch in most regions displayed strong periodicity that corresponded to seasons (~365 days) and/or moon phase (~29 days). When trends in catch and bycatch rates were examined by month and moon phase, the significant periods of higher and lower catch and bycatch related to swordfish (Xiphias gladius), yellowfin tuna (Thunnus albacares), and sea turtle temporal distributions in foraging and spawning/nesting, oceanographic and prey conditions, and foraging behavior. Catch and bycatch rates tended to depend more on a seasonal rather than a lunar time scale, although there is likely an interaction between the two. These findings provide insights to the susceptibility of target catch and bycatch, regional and temporal patterns of fishing effort, and potential guidance for resource management and conservation.
OBIS-SEAMAP: an online portal for marine mammal observations
Lucie J. Hazen, Ei Fujioka, Patrick. N. Halpin, Andrew J. Read, Benjamin D. Best, Connie Y. Kot, Kimberly Urian, Benjamin Donnelly, Andrew DiMatteo, Erin A. LaBrecque, Melissa Soldevilla, and Caroline Good
OBIS-SEAMAP, an online information system for marine mammal, seabird and sea turtle data, is an open access repository and web-based data center of high quality observations.OBIS-SEAMAP brings together georeferenced sightings, telemetry and acoustics data with tools to query and assess these species in a dynamic and searchable environment. By combining data from individual research programs at multiple spatial and temporal scales into a global database, we can obtain a more complete picture of the biology, distribution and conservation status of these widely distributed animals. The open-access web-based approach utilized by OBIS-SEAMAP allows a global audience of researchers, students, educators and managers to: 1) map species distributions together with oceanographic information; 2) visualize species distributions with a multi-resolution, spatially and temporally interactive online map interface; and 3) search and download data of interest using multi-faceted criteria. Significantly, data providers benefit from the secure off-site back-up service, the opportunity to reach a global audience and the resultant collaborative potential, increased data quality assurance and quality control, and a suite of visualization tools to examine their own data geographically and temporally.
Our ability to understand, conserve and manage marine biodiversity is fundamentally limited by the availability of relevant taxonomic, distribution and abundance data. The OBIS-SEAMAP is a web-based geo-database of marine mammal, seabird (including sea ducks) and sea turtle distribution and abundance data globally. The OBIS-SEAMAP information system is aimed to support research, management and conservation of marine megavertebrates through promoting scientific data commons and providing users with a broad array of web-based products and services. The database supports georeferenced data of animal distributions at sea, colony based counts and tracking information and is
open to all marine biologists sharing vision of data commons and partnership. Boat, shore and aerial surveys and telemetry data are submitted by government, academic, industry and non-profit providers by communicating directly with archive developers and using data content management system. Contributing satellite tracking information might seem particularly appealing to sea duck investigators and ongoing tracking data could be assimilated directly through Satellite Tracking and Analysis Tool (STAT). The OBIS-SEAMAP archive is equipped with multi-faceted data search and extraction, state-of-art online mapping and cutting edge viewing features, including animated animal movements, which will be demonstrated at the Sea Duck Conference using a sample of an actual sea duck tracking dataset. Contributed datasets are standardized, integrated with rich species profiles and compliant metadata. In addition to benefiting from the toolset available at OBIS-SEAMAP, data contributors increase their visibility, public outreach and develop potential for new collaborations. We encourage you to contribute your datasets to OBIS-SEAMAP and to contact us with suggestions of how to refine and improve the archive. The OBIS-SEAMAP database is accessible online at: http://seamap.env.duke.edu.
The science needed to understand highly migratory marine mammal, sea bird and sea turtle species is not adequately addressed by individual data collections developed for a single region or single time period. These data must to be brought together into a common, global map based on a coherent, interoperable and openly accessible information system. This need was clearly articulated by the National Ocean Partnership Program (NOPP) in partnership with the Alfred P. Sloan Foundation when they sponsored a new effort to directly address this issue in 2002. The result is OBIS-SEAMAP: The world data-center for marine mammal, sea bird and sea turtle information. OBIS-SEAMAP brings together georeferenced distribution, abundance and telemetry data with tools to query and assess these species in a dynamic and searchable environment. In a second round of NOPP support beginning in 2007, the National Science Foundation is helping expand this effort into new technologies and data types. To date, the OBIS-SEAMAP information system includes more than 2.2 million observation records from over 230 datasets, spanning 73 years (1935 - 2008) and growth of this data archive is accelerating. All of these data are provided by a growing international network of individual and institutional data providers.
We report on the ongoing development and improvement of a digital information system which provides critical data on the distribution of marine megavertebrates to scientists, managers and educators. The OBIS-SEAMAP (Ocean Biogeographic Information System - Spatial Ecological Analysis of Megavertebrate Populations) program (http://seamap.env.duke.edu) is designed to make high-quality data sets, ecological models and expert knowledge available to these communities. The archive currently hosts 212 datasets including over 1.15 million observations. We are in the midst of a comprehensive inventory and data exploration, so these numbers will markedly increase in the near future. Now in its fifth year, the project provides a suite of advanced web services for the storage, analysis and visualization of geospatial datasets related to the biogeography of marine mammals, seabirds and sea turtles. Boat, shore and aerial surveys and telemetry data are submitted by government, academic, industry and non-profit providers through an automated data content management system. With three additional years of funding secured from the National Oceanographic Partnership Program and the National Science Foundation, we are working to enhance this archive by incorporating new data types (acoustics, photo-id, 3D dive profiles), model outputs, web services, environmental sampling capabilities, and automated population of metadata clearinghouses. We encourage you to contribute your data sets to OBIS-SEAMAP and to contact us with suggestions of how to refine and improve the archive.
Bycatch in fisheries has been recognized as a threat to many endangered populations of sea turtles, sea birds and marine mammals. Interactions between pelagic longline fisheries and critically endangered populations of leatherback sea turtles (Dermochelys coriacea) have led to temporary closures of the Hawaiian pelagic longline swordfish fishery and severe bycatch quotas. The negative impact of these events on both the populations of certain endangered species and the economic livelihood of the fishermen has resulted in a strong push from all sides to better understand bycatch events. Typically, analyses of longline catch and bycatch have examined fishing effort summarized over large areas (=1 degree). Although aggregation of effort to this level may be necessary to account for uncertainty, confidentiality concerns, or to make comparisons across regions, it specifically limits the researcher's ability to characterize the local oceanographic factors that may drive individual bycatch events. Higher resolution analyses must be undertaken to identify such features. However, for these higher resolution analyses, the methods currently used to spatially represent pelagic longline fishing effort may significantly affect researcher's results. Here, we look at different methods to represent this fishing effort (i.e., points, centroids, polylines and polygons) at various resolutions (2 km to 5 degrees) to better understand which method and spatial resolution are most appropriate. Our results validate the use of point features to represent fishing effort in previous low resolution studies of the Hawaiian pelagic longline fishery by showing that the set point method is suitable for studies with resolutions lower than 15 km. However, at higher resolutions (= 15 km) and in areas with more sparsely distributed fishing, aggregated effort values differed significantly between spatial representation methods. We demonstrate that the use of polygons to describe pelagic longline fishing effort is more representative and necessary for such high resolution analyses.
Fisheries bycatch has been identified as an important source of mortality for many sea turtle populations in the Western Central Atlantic. Formal assessments are scarce and are typically restricted geographically (e.g., Trinidad and Tobago; the Guianas) or by gear type (e.g., industrial or semi-industrial trawls and longlines). Our objective was to develop a region-wide assessment of sea turtle bycatch as part of a global, multi-taxa assessment sea turtle, marine mammal and seabird bycatch. Using multiple approaches (literature review, interview-based surveys, and observer data) our analysis provides a comprehensive overview of the current status of knowledge of sea turtle bycatch. The results are used to generate a preliminary model of the relationship between fishing intensity, oceanography and bycatch risk.
Five species of sea turtles inhabiting the Atlantic Ocean and Gulf of Mexico are listed as either endangered or threatened under the Endangered Species Act (ESA). None of the species have yet met the recovery goals outlined in their respective recovery plans. To help meet ESA recovery goals for sea turtles, NOAA's National Marine Fishery Service (NMFS) is implementing a strategy for sea turtle conservation and recovery in relation to Atlantic Ocean and Gulf of Mexico fisheries to reduce incidental capture of sea turtles in commercial and recreational fisheries. A strategic approach evaluating fishery impacts by gear types across state, federal, and regional boundaries will increase management effectiveness. The development of a dynamic GIS by NOAA's Biogeography Program for sea turtles to facilitate the implementation of the strategy is a key baseline need and will also assist NMFS in meeting other ESA and legislative responsibilities.