Mediterranean nekton traits: distribution, relationships and significance for marine ecology monitoring and management

Abstract

Biological traits are increasingly used in order to study aspects of ecology as they are related to the organisms’ fitness. Here we analyze a dataset of 23 traits regarding the life cycle, distribution, ecology and behavior of 235 nektonic species of the Mediterranean Sea in order to evaluate the distribution of traits, identify rare ones, detect relationships between trait pairs and identify species functional groups. Trait relationships were tested using correlation and non-linear regression for continuous traits, parametric and non-parametric inference tests for pairs of continuous-categorical traits and cooccurrence testing for categorical traits. The findings have significant implications concerning the potential effects of climate change (e.g., through the relationships of the trait of optimal temperature), fisheries or habitat loss (from the relationships of traits related to tolerance ranges). Furthermore, some unexpected relationships are documented, like the inversely proportional relationship between longevity and age at maturity as a percentage of life span. Associations between functional traits show affinities derived from phylogenetic constraints or life strategies; however, relationships among functional and ecological traits can indicate the potential environmental filtering that acts on functional traits. In total, 18 functional groups were identified by Hill-Smith ordination and hierarchical clustering and were characterized by their dominant traits. For the assessment of the results, we first evaluate the importance of each trait at the level of population, community, ecosystem and landscape and then propose the traits that should be monitored for the regulation and resilience of ecosystem functioning and the management of the marine ecosystems.

An Integrated Traits Resilience Assessment of Mediterranean fisheries landings

“…For each trait, two to six trait categories (also called modalities) were created in a fashion where a species could be assigned to only one modality per trait, resulting in a total of 81 modalities for which a species had presence/absence scores (Table 1). More information on the dataset, species selection, modality delimitation and information sources can be found in the study by Tzanatos et al (2020). The dataset is available at: https:// figsh are.com/artic les/Kouts idi_Moukas_Tzana tos_23_biolo gical_ traits_of_235_speci es/11347406…”

“…The 23 nekton traits used with their respective trait categories/modalities | 2125 modality delimitation and information sources can be found in the study by Tzanatos et al (2020). The dataset is available at: https:// figsh are.com/artic les/Kouts idi_Moukas_Tzana tos_23_biolo gical_ traits_of_235_speci es/11347406…”

Merging trait‐based ecology and regime shift theory to anticipate community responses to warming

“…Some environmental stressors disproportionately affect individuals with certain traits, such as the strong negative impact of ocean acidification on shell-forming organisms (Kroeker et al, 2010(Kroeker et al, , 2011. Trait expression changes at the individual level in turn influence fitness and function of populations (Tzanatos et al, 2020;Villéger et al, 2017;Violle et al, 2007). However, populations do not respond to environmental conditions in a vacuum.…”

Can Biological Traits Serve as Predictors for Fishes’ Introductions, Establishment, and Interactions? The Mediterranean Sea as a Case Study

“…This trait-related invasion has been addressed in a number of recent works (e.g., [ 18 , 19 , 20 , 21 ]) and has also been tested in range expansion within the invaded regions (e.g., [ 22 , 23 ]). Yet, these efforts have addressed and analyzed the ichthyofauna of one area/regional sea, while there is little comparison with the biota of neighboring areas.…”