Review Application of management tools to integrate ecological principles with the design of marine infrastructure Katherine A. Dafforn a, b, * , Mariana Mayer-Pinto a, b , Rebecca L. Morris c , Nathan J. Waltham d a Evolution & Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia b Sydney Institute of Marine Sciences, Mosman, NSW 2088, Australia c Centre for Research on the Ecological Impacts of Coastal Cities, University of Sydney, Sydney, NSW 2006, Australia d TropWATER, Centre for Tropical Water and Aquatic Ecosystem Research, James Cook University, Townsville, QLD 4811, Australia article info Article history: Received 16 February 2015 Received in revised form 28 April 2015 Accepted 1 May 2015 Available online Keywords: Marine urban development Offshore energy installations Policy Marine spatial planning Eco-engineering Managed realignment abstract Globally the coastal zone is suffering the collateral damage from continuing urban development and construction, expanding resource sectors, increasing population, regulation to river flow, and on-going land change and degradation. While protection of natural coastal habitat is recommended, balancing conservation with human services is now the challenge for managers. Marine infrastructure such as seawalls, marinas and offshore platforms is increasingly used to support and provide services, but has primarily been designed for engineering purposes without consideration of the ecological consequences. Increasingly developments are seeking alternatives to hard engineering and a range of ecological solu- tions has begun to replace or be incorporated into marine and coastal infrastructure. But too often, hard engineering remains the primary strategy because the tools for managers to implement ecological so- lutions are either lacking or not supported by policy and stakeholders. Here we outline critical research needs for marine urban development and emerging strategies that seek to mitigate the impacts of marine infrastructure. We present case studies to highlight the strategic direction necessary to support management decisions internationally. © 2015 Elsevier Ltd. All rights reserved. 1. Introduction Continuing human population growth and corresponding expansion of coastal cities has contributed to a modern day multi- use seascape including natural and engineered habitat features (e.g. Lee et al., 2006; Waltham and Connolly, 2011). Along with essential ecological services for fisheries production (Nagelkerken et al., 2013), the modern day seascape is also expected to provide ser- vices essential for humans, such as residential living, recreation, commercial, navigation, wastewater disposal and tourism activities (Dennison, 2008). Costanza et al. (1997) estimated these marine and coastal services to be worth in the order of US$31.5 trillion yr À1 . The challenge for coastal managers is to now balance ecological biodiversity and habitat protection at the same time as approving expansion of coastal centres and development. To move forward in the management of marine developments, we require a clear definition of what constitutes “marine infra- structure”. We propose that the term includes basic recreational infrastructure (e.g. marinas, pilings, pontoons, boat ramps, swim- ming enclosures), coastal and foreshore defence infrastructure (e.g. seawalls, groynes, breakwaters), offshore energy installations (e.g. gas and oil extraction, wind farms), fisheries infrastructure (artifi- cial reefs, offshore aquaculture facilities) and residential infra- structure (canal estates, bridge crossings). Currently these “marine infrastructure” are differentially managed, and lack comprehensive or consistent guidelines and regulations for their planning, con- struction and restoration. Clear objectives for the management of marine developments will be essential in the future as the construction of infrastructure is forecast to increase considerably with the increasing urbani- zation of space and predicted climatic changes (Asif and Muneer, 2007; Dugan et al., 2011; P erez-Alberti et al., 2013; Troell et al., 2009). For example, a significant amount of urban shorelines are occupied by marinas and recreational infrastructure (Table 1). In Australia, Sydney Harbour alone comprises almost 40 marinas * Corresponding author. School of BEES, University of NSW, Sydney, NSW 2052, Australia. E-mail address: k.dafforn@unsw.edu.au (K.A. Dafforn). Contents lists available at ScienceDirect Journal of Environmental Management journal homepage: www.elsevier.com/locate/jenvman http://dx.doi.org/10.1016/j.jenvman.2015.05.001 0301-4797/© 2015 Elsevier Ltd. All rights reserved. Journal of Environmental Management 158 (2015) 61e73