Population connectivity and the effectiveness of marine protected areas to protect vulnerable, exploited and endemic coral reef fishes at an endemic hotspot

Abstract

Marine protected areas (MPAs) aim to mitigate anthropogenic impacts by conserving biodiversity and preventing overfishing. The effectiveness of MPAs depends on population connectivity patterns between protected and nonprotected areas. Remote islands are endemism hotspots for coral reef fishes and provide rare examples of coral reefs with limited fishing pressure. This study explored population genetic connectivity across a network of protected and non-protected areas for the endemic wrasse, Coris bulbifrons, which is listed as ''vulnerable'' by the IUCN due to its small, decreasing geographic range and declining abundance. Mitochondrial DNA (mtDNA) and microsatellite DNA (msatDNA) markers were used to estimate historic and contemporary gene flow to determine the level of population self-replenishment and to measure genetic and genotypic diversity among all four locations in the species range (south-west Pacific Ocean)-Middleton Reef (MR), Elizabeth Reef (ER), Lord Howe Island (LHI) and Norfolk Island (NI). MPAs exist at MR and LHI and are limited or nonexistent at ER and NI, respectively. There was no obvious differentiation in mtDNA among locations, however, msatDNA revealed differentiation between the most peripheral (NI) and all remaining locations (MR, ER and LHI). Despite high mtDNA connectivity (M = 259-1,144), msatDNA connectivity was limited (M = 3-9) with high self-replenishment (68-93 %) at all locations. NI is the least connected and heavily reliant on self-replenishment, and the absence of MPAs at NI needs to be rectified to ensure the persistence of endemic species at this location. Other endemic fishes exhibit similar patterns of high self-replenishment across the four locations, indicating that a single spatial management approach consisting of a MPA network protecting part of each location could provide reasonable protection for these species. Thus, the existing network of MPAs at this endemic hotspot appears adequate at some locations, but not at all.

Lack of recognition of genetic biodiversity: International policy and its implementation in Baltic Sea marine protected areas

“…Similarly, the importance of including genetic considerations in MPA management is increasingly highlighted (Arizmendi-Mejía et al 2015; van der Meer et al 2015). …”

“…The lack of explicit genetic goals for MPAs in the Baltic Sea is unfortunate considering the particular importance of genetic diversity in this area (Johannesson et al 2011 ); increasingly accumulating research indicates that genetic adaption to the particular environment has evolved and reflect ongoing speciation (Lamichhaney et al 2012 ; Berg et al 2015 ). Similarly, the importance of including genetic considerations in MPA management is increasingly highlighted (Arizmendi-Mejía et al 2015 ; van der Meer et al 2015 ).…”

Larval dispersal model of coral Acropora in the Karimunjawa Waters, Indonesia

“…A better understanding on the period and larval dispersal pattern in the conservation area will increase the understanding of recruitment and connectivity among reefs (Kool and Nichol 2015;van der Meer et al 2015;Storlazzi et al 2017). Then, the research on modeling of larval dispersal is urgently needed to be conducted.…”