Ecological Indicators 37 (2014) 105–118 Contents lists available at ScienceDirect Ecological Indicators jou rn al hom epage: www.elsevier.com/locate/ecolind Can different biological indicators detect similar trends of marine ecosystem degradation? Sofia Henriques a,∗ , Miguel Pessanha Pais a , Marisa Isabel Batista a , Célia M. Teixeira a , Maria José Costa a,b , Henrique Cabral a,b a Centro de Oceanografia, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal b Departamento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal a r t i c l e i n f o Article history: Received 12 April 2013 Received in revised form 8 October 2013 Accepted 13 October 2013 Keywords: Benthic macroinvertebrate assemblages Fish assemblages Marine soft-substrates Structural and functional approach Anthropogenic pressures Human pressure index a b s t r a c t Marine ecosystems are typically under the influence of multiple Human activities, which hinders the assessment of the effects of a specific activity upon their biological assemblages. In this context, distance- based linear models were used to analyse the relationships of several structural and functional metrics of both macroinvertebrates and fish assemblages with the specific types of pressure (i.e. fishing, organic, physical and non-point-source) as well as the global pattern of cumulative pressures. Both indicators detected similarly the effects of the global degradation and the analyses of the metrics’ sensitivity (given the expected response trends) suggested that the non-point-source had the strongest contribution to this pattern, followed by organic pollution. The difficulties of assessing single pressure effects in a multiple pressures context are discussed. An approach based on the previous identification of pressure sources, a sampling strategy directed to those sources, together with indicator response is highly recommended, as it could be the only way to accurately predict human-induced changes on broad range ecosystems, with likely implications in the success of marine management plans. © 2013 Elsevier Ltd. All rights reserved. 1. Introduction Awareness of the harmful effects of human pressures on the marine environment has resulted in an increasing attention to monitoring using biological indicators, in order to identify which human pressures are driving changes on the ecosystem structure and function, as well as design management plans to minimize impacts (Niemi et al., 2004; Rogers and Greenaway, 2005; Smale et al., 2010). In this context, recent policies have been developed with the purpose of promoting sustainable use of marine resources and protect marine ecosystems (e.g. Marine Strategy Framework Directive, MSFD; Directive 2008/56/CE). To implement the MSFD, an integrated ecosystem-based approach should be applied, giving priority to the attainment of a “good environmental status” through the assessment of physical and chemical elements, together with several biological indicators, among which are fish and macroin- vertebrates (see Annex III in Directive 2008/56/CE). Due to the difficulty of analysing patterns of change in com- plex, spatially and temporally diverse multi-species assemblages, the need to assess environmental status comes with new challenges concerning the use of biological indicators in marine waters (Mee ∗ Corresponding author. Tel.: +351 217500826; fax: +351 750 02 07. E-mail addresses: snpires@fc.ul.pt, henriques.sofia@gmail.com (S. Henriques). et al., 2008; Niemi et al., 2004; Niemi and McDonald, 2004). Addi- tionally, stress in marine ecosystems is usually characterized by the effects of multiple human pressure sources, and as physical boundaries between marine habitats are difficult to define, thus the identification of pressures that are affecting an area consti- tutes a complex task (Ban et al., 2010; Niemi et al., 2004). This way, coupling human pressure and biological response analyses is essential to link the causes of stress to the response of indicators. Otherwise, it would be extremely difficult to identify sources of dis- turbance, unless specific metrics for each pressure exist and detect such changes (Niemi et al., 2004; Niemi and McDonald, 2004). Earlier attempts at comparing the response of fish-based and macroinvertebrate-based metrics have been focused on freshwater ecosystems (e.g. Hering et al., 2006; Johnson et al., 2006; Marzin et al., 2012). In general, these studies showed that macroinver- tebrates and fish have different sensitivities depending on the human pressure analysed, with fish responding more to hydrolog- ical changes, while macroinvertebrates show a higher sensitivity to water quality and/or geomorphological changes (Hering et al., 2006; Marzin et al., 2012). However, these assemblages differ deeply from those of marine waters. For example, fish assemblages are known to be species-poor in streams (Hering et al., 2006). To the best of our knowledge, only few studies have compared the response of multiple indicators in coastal waters (marine and estu- arine ecosystems), but through multimetric indices (e.g. Azevedo 1470-160X/$ – see front matter © 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ecolind.2013.10.017