Anticipating changes to future connectivity within a network of marine protected areas.

Melinda A Coleman,Paulina Cetina‐Heredia,Ming Feng,Erik Van Sebille,Moninya Roughan,Brendan P Kelaher

doi:10.1111/gcb.13634

Abstract

Continental boundary currents are projected to be altered under future scenarios of climate change. As these currents often influence dispersal and connectivity among populations of many marine organisms, changes to boundary currents may have dramatic implications for population persistence. Networks of marine protected areas (MPAs) often aim to maintain connectivity, but anticipation of the scale and extent of climatic impacts on connectivity are required to achieve this critical conservation goal in a future of climate change. For two key marine species (kelp and sea urchins), we use oceanographic modelling to predict how continental boundary currents are likely to change connectivity among a network of MPAs spanning over 1000km of coastline off the coast of eastern Australia. Overall change in predicted connectivity among pairs of MPAs within the network did not change significantly over and above temporal variation within climatic scenarios, highlighting the need for future studies to incorporate temporal variation in dispersal to robustly anticipate likely change. However, the intricacies of connectivity between different pairs of MPAs were noteworthy. For kelp, poleward connectivity among pairs of MPAs tended to increase in the future, whereas equatorward connectivity tended to decrease. In contrast, for sea urchins, connectivity among pairs of MPAs generally decreased in both directions. Self-seeding within higher-latitude MPAs tended to increase, and the role of low-latitude MPAs as a sink for urchins changed significantly in contrasting ways. These projected changes have the potential to alter important genetic parameters with implications for adaptation and ecosystem vulnerability to climate change. Considering such changes, in the context of managing and designing MPA networks, may ensure that conservation goals are achieved into the future.

Highlights

Continental boundary currents are projected to change under climate change (Wu et al, 2012; Sen Gupta et al, 2015)
2015) and temporal (Blowes & Connolly, 2012) variability in dispersal distance and spread affects the likelihood of population persistence, understanding variability in dispersal and connectivity is a key component of marine protected areas (MPAs) network planning (Pendoley et al, 2014)
Connectivity among marine parks within the network varied greatly among years in both the contemporary and future scenarios, and this variation resulted in no statistical difference in each park acting as a source or sink between contemporary and future scenarios (PERMANOVA, Time: P > 0.05 for all parks, Fig. 3a, b)

Summary

Introduction

Continental boundary currents are projected to change under climate change (Wu et al, 2012; Sen Gupta et al, 2015). The size, spacing and arrangement of MPAs relative to scales of dispersal and life history of organisms (Shanks et al, 2003; Durrant et al, 2014), combined with local- and regional-scale oceanography (Roberts, 1997) and other environmental factors, determine the extent to which MPAs are connected and contribute to conservation goals. Given that both spatial (Castorani et al., 2015) and temporal (Blowes & Connolly, 2012) variability in dispersal distance and spread affects the likelihood of population persistence, understanding variability in dispersal and connectivity is a key component of MPA network planning (Pendoley et al, 2014). Future changes to connectivity should ideally be considered and anticipated in conservation initiatives to allow appropriate review of MPA designs and to ensure that MPAs achieve their conservation goals both and into the future (Magris et al, 2014; Parsons et al, 2014)

Methods

Results

Conclusion