Assessing cetacean surveys throughout the Mediterranean Sea: a gap analysis in environmental space
Laura Mannocci
(1, 2)
,
Jason Roberts
(3, 2)
,
Patrick Halpin
(2)
,
Matthieu Authier
(4)
,
Oliver Boisseau
(5)
,
Mohamed Nejmeddine Bradai
,
Ana Canadas
(6)
,
Carla Chicote
(7)
,
Léa David
(8)
,
Nathalie Di-Méglio
(8)
,
Caterina Fortuna
(9)
,
Alexandros Frantzis
(10)
,
Manel Gazo
(7)
,
Tilen Genov
(11)
,
Philip S. Hammond
(12)
,
Draško Holcer
(13, 14)
,
Kristin Kaschner
(15)
,
Dani Kerem
(16)
,
Giancarlo Lauriano
,
Tim Lewis
(17)
,
Giuseppe Notarbartolo Di Sciara
(18)
,
Simone Panigada
(18)
,
Juan Antonio Raga
(19)
,
Aviad Scheinin
(16)
,
Vincent Ridoux
(20)
,
Adriana Vella
(21)
,
Joseph Vella
(22)
1
LIENSs -
LIttoral ENvironnement et Sociétés
2 Marine Geospatial Ecology Laboratory [USA]
3 Duke University Marine Laboratory
4 PELAGIS - Observatoire pour la Conservation de la Mégafaune Marine
5 Marine Conservation Research (MCR) [UK]
6 Alnilam Investigación y Conservación
7 SUBMON - Marine Environmental Services [SPAIN]
8 EcoOcéan Institut [FRANCE]
9 ISPRA - National Institute for Environmental Protection and Research
10 Pelagos Cetacean Research Institute [GREECE]
11 Morigenos – Slovenian Marine Mammal Society [Slovenia]
12 SMRU - Sea Mammal Research Unit [University of St Andrews]
13 Croatian Natural History Museum
14 Blue World Institute of Marine Research and Conservation [CROATIE]
15 Department of Biometry and Environmental System Analysis
16 Israel Marine Mammal Research & Assistance Center
17 OU - The Open University [Milton Keynes]
18 Tethys Research Institute [ITALIE]
19 Unidad de Zoologia Marina [SPAIN]
20 CEBC - Centre d'Études Biologiques de Chizé - UMR 7372
21 Conservation Biology Research Group [MALTA]
22 The Biological Conservation Research Foundation [MALTA]
2 Marine Geospatial Ecology Laboratory [USA]
3 Duke University Marine Laboratory
4 PELAGIS - Observatoire pour la Conservation de la Mégafaune Marine
5 Marine Conservation Research (MCR) [UK]
6 Alnilam Investigación y Conservación
7 SUBMON - Marine Environmental Services [SPAIN]
8 EcoOcéan Institut [FRANCE]
9 ISPRA - National Institute for Environmental Protection and Research
10 Pelagos Cetacean Research Institute [GREECE]
11 Morigenos – Slovenian Marine Mammal Society [Slovenia]
12 SMRU - Sea Mammal Research Unit [University of St Andrews]
13 Croatian Natural History Museum
14 Blue World Institute of Marine Research and Conservation [CROATIE]
15 Department of Biometry and Environmental System Analysis
16 Israel Marine Mammal Research & Assistance Center
17 OU - The Open University [Milton Keynes]
18 Tethys Research Institute [ITALIE]
19 Unidad de Zoologia Marina [SPAIN]
20 CEBC - Centre d'Études Biologiques de Chizé - UMR 7372
21 Conservation Biology Research Group [MALTA]
22 The Biological Conservation Research Foundation [MALTA]
Jason Roberts
- Fonction : Auteur
- PersonId : 774282
- ORCID : 0000-0001-6218-435X
- IdRef : 224700251
Matthieu Authier
- Fonction : Auteur
- PersonId : 920952
Mohamed Nejmeddine Bradai
- Fonction : Auteur
Philip S. Hammond
- Fonction : Auteur
- PersonId : 874279
Giancarlo Lauriano
- Fonction : Auteur
Résumé
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.