Biodiversity Monitoring in Mediterranean Marine Protected Areas: Scientific and Methodological Challenges

Abstract

Biodiversity is a portmanteau word to indicate the variety of life at all levels from genes to ecosystems, but it is often simplistically equated to species richness; the word ecodiversity has thus been coined to address habitat variety. Biodiversity represents the core of the natural capital, and as such needs to be quantified and followed over time. Marine Protected Areas (MPAs) are a major tool for biodiversity conservation at sea. Monitoring of both species and habitat diversity in MPAs is therefore mandatory and must include both inventory and periodic surveillance activities. In the case of inventories, the ideal would be to census all species and all habitats, but while the latter goal can be within reach, the former seems unattainable. Species inventory should be commeasured to investigation effort, while habitat inventory should be based on mapping. Both inventories may profit from suitability spatial modelling. Periodic surveillance actions should privilege conspicuous species and priority habitats. Efficient descriptor taxa and ecological indices are recommended to evaluate environmental status. While it seems obvious that surveillance activities should be carried out with regular recurrence, diachronic inventories and mapping are rarely carried out. Time series are of prime importance to detect marine ecosystem change even in the absence of direct human impacts.

Assessing the Effect of Full Protection on the Biomass of Ericaria amentacea and Understory Assemblages: Evidence from Two Mediterranean Marine Protected Areas

“…Assessing the effectiveness of MPAs is crucial to ensure the achievement of conservation goals and to refine conservation strategies for an adaptive management of protected communities in the face of changing environmental conditions [49,50]. In most cases, assessments of the ecological effects of MPAs, and particularly of full protection in no-take zones, have focused on fish documenting increased assemblage diversity, abundance and biomass of protected populations with respect to unprotected areas [51][52][53][54][55].…”

Distribution and Ecology of Decapod Crustaceans in Mediterranean Marine Caves: A Review

“…Thus, to make comparable the cave decapod species richness in the different sectors of the Mediterranean Sea, the cumulative number of species has been plotted against the number of caves surveyed in each sector (Figure 3). Curves were fitted to these plots according to the equation S = c•N z , where S is the number of species, N is the number of caves, c gives the number of species that may be expected in one cave and z is the slope of the regression line relating S and N [37,38]. Plotting the reciprocals of the cumulative number of species against the reciprocals of the number of caves was also tried.…”

Ecosystem-based assessment of a widespread Mediterranean marine habitat: The Coastal Detrital Bottoms, with a special focus on epibenthic assemblages

“…(Bianchi et al, 2004;Astruch et al, 2012;Valette-Sansevin et al, 2019) and prediction models (Martin et al, 2014;Vassallo et al, 2018), the mapping of CDB is still challenging. The assessment of coastal water body masses, marine habitats or ecosystems involves numerous indices with different purposes (Bianchi et al, 2022). None of these indices alone offers an adequate basis for solving all the issues: specific descriptors may assess the ecological status linked with water quality (WFD; e.g., Borja et al, 2000;Borja et al, 2003;Ballesteros et al, 2007;Gobert et al, 2009;Lopez y Royo et al, 2010;Piazzi et al, 2021), ecosystem functioning (descriptor 1 of the MSFD; e.g., Personnic et al, 2014;Montefalcone et al, 2015a;Giakoumi et al, 2015), seafloor integrity (descriptor 6 of the MSFD; e.g., Montefalcone et al, 2007;Gatti et al, 2015;Enrichetti et al, 2019;Piazzi et al, 2019), the conservation status of natural habitats (HD; e.g., Maciejewski et al, 2016;Sartoretto et al, 2017), natural and anthropogenic stressors (Holon et al, 2015;La Rivière et al, 2017;Ruitton et al, 2020).…”

“…The aim of the present work is to develop and apply a new EBQI expressly designed for CDB (Astruch et al, 2022a). Although CDB is traditionally identified mostly on the basis of the study of the infaunal component, which requires sampling with grabs or dredges operated from large vessels, the approach presented here will focus on the epibenthic component, which can be studied with a lighter and less costly approach, i.e., photographic, video and/or visual techniques -to be privileged in a conservation context (Bianchi et al, 2022). The effectiveness of this novel index was tested along the coasts of Provence and French Riviera (France, Mediterranean Sea) (Figure 1).…”