Assessing cetacean surveys throughout the Mediterranean Sea : a gap analysis in environmental space
Abstract
Heterogeneous data collection in the marine environment has led to large gaps in our knowledge of marine species distributions. To fill these gaps, models calibrated on existing data may be used to predict species distributions in unsampled areas, given that available data are sufficiently representative. Our objective was to evaluate the feasibility of mapping cetacean densities across the entire Mediterranean Sea using models calibrated on available survey data and various environmental covariates. We aggregated 302,481 km of line transect survey effort conducted in the Mediterranean Sea within the past 20 years by many organisations. Survey coverage was highly heterogeneous geographically and seasonally: large data gaps were present in the eastern and southern Mediterranean and in non-summer months. We mapped the extent of interpolation versus extrapolation and the proportion of data nearby in environmental space when models calibrated on existing survey data were used for prediction across the entire Mediterranean Sea. Using model predictions to map cetacean densities in the eastern and southern Mediterranean, characterised by warmer, less productive waters, and more intense eddy activity, would lead to potentially unreliable extrapolations. We stress the need for systematic surveys of cetaceans in these environmentally unique Mediterranean waters, particularly in non-summer months.
Citation
Mannocci , L , Roberts , J J , Halpin , P N , Authier , M , Boisseau , O , Bradai , M N , Cañadas , A , Chicote , C , David , L , Di-Méglio , N , Fortuna , C M , Frantzis , A , Gazo , M , Genov , T , Hammond , P S , Holcer , D , Kaschner , K , Kerem , D , Lauriano , G , Lewis , T , Notarbartolo di Sciara , G , Panigada , S , Raga , J A , Scheinin , A , Ridoux , V , Vella , A & Vella , J 2018 , ' Assessing cetacean surveys throughout the Mediterranean Sea : a gap analysis in environmental space ' , Scientific Reports , vol. 8 , 3126 . https://doi.org/10.1038/s41598-018-19842-9
Publication
Scientific Reports
Status
Peer reviewed
ISSN
2045-2322Type
Journal article
Rights
Copyright © The Author(s) 2018. Open Access. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
Description
Authors thank United States Fleet Forces Command and Naval Facilities Engineering Command Atlantic for funding and support for the development of this gap analysis.Collections
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