Increase in Relative Abundance and Size of Snapper Chrysophrys auratus Within Partially-Protected and No-Take Areas in a Temperate Marine Protected Area

Abstract

Marine Protected Areas (MPAs) are known to contribute toward the conservation of marine biodiversity, particularly targeted fishery species. Snapper Chrysophrys auratus are an important recreational and commercial fish species in New South Wales (NSW), Australia, and despite fishery management for this species, they are considered "growth overfished" in this region. To assess how C. auratus respond to the implementation of an MPA with several no-take and partially protected areas in temperate NSW, we monitored their populations over a decade (2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015)(2016)(2017) using baited remote underwater video systems (BRUVs). Surveys were conducted in the Port Stephens-Great Lakes Marine Park with BRUVs deployed on rocky reefs in depths of 20-50 m. Long term seasonal sampling (winter vs. summer) was undertaken at two locations (Broughton and Fingal Island), and changes in C. auratus abundance prior to, and 8 years after zoning implementation, were assessed between these two locations. In total, we sampled five no-take areas within the marine park and five comparative nearby partially protected fished areas and three sites located outside the marine park boundaries. The most pronounced changes in abundance and size structure for C. auratus were observed in the Broughton Island no-take area where numbers increased almost 3-fold (2.91 times) over 8 years of protection. Relative abundance showed seasonal variation at two locations, and we consistently recorded increasing abundance within no-take areas at Broughton and Fingal Island compared to nearby sites open to fishing. Surveys across the five no-take areas found a significant increase in the abundance of C. auratus, whilst the five partially-protected locations in the marine park still recorded higher abundances than sites outside the marine park. In addition, length measurements from stereo-BRUVS indicated that C. auratus were significantly larger in no-take areas compared to partially-protected areas in the marine park and sites outside the marine park. This study demonstrates how the implementation of the marine park and the protection afforded by no-take and partially-protected areas provides refuge for this important fishery targeted species.

Predictive modelling of illegal fishing in no‐take marine protected areas

“…Data were examined on fishing activity in two NTAs in the Port Stephens–Great Lakes Marine Park (PSGLMP) in New South Wales (NSW), Australia, to improve understanding about the influence of how short‐term temporal factors influence illegal fishing in NTAs. The PSGLMP is a popular region for recreational fishing (Read, West, Haste, & Jordan, ) and is an important area for fishery target species such as snapper Chrysophrys auratus (Forster), which are in high relative abundance in NTAs compared with fished areas (Harasti, Davis, Mitchell, Lindfield, & Smith, ; Harasti, Williams, Mitchell, Lindfield, & Jordan, ) and also display strong site fidelity within a NTA (Harasti, Lee, Gallen, Hughes, & Stewart, ). A study by Harasti et al () reported illegal recreational fishing within a NTA reduced both the size and abundance of C. auratus .…”

The influence of protection and temperature on subtropical reef fish assemblages in Cape Byron Marine Park

“…In this paper we have added to the relatively well established body of literature documenting the positive effects that the establishment of no‐take marine reserves has on the abundance of fish targeted by anglers (e.g. Evans & Russ, ; Harasti et al, ; Lester et al, ; Williamson et al, ; Willis et al, ). We also found, not surprisingly, that different species of fish appear to respond differently to changes in temperature and that the responses of suites of species of fish to changing temperature may be relatively complex and unpredictable.…”

“…Marine Protected Areas (MPAs), which include 'no-take' zones, of appropriate habitat configuration and size have been shown to be highly effective tools for conserving fish biodiversity, and for the sustainable management of fish populations, including relatively small New Zealand marine reserves (Babcock, Kelly, Shears, Walker, & Willis, 1999;Shears & Babcock, 2002). Not only are the individuals of species targeted by fishers generally more abundant and larger in no-take zones (Evans & Russ, 2004;Harasti, Williams, Mitchell, Lindfield, & Jordan, 2018;Williamson, Russ, & Ayling, 2004;Willis, Parsons, & Babcock, 2001), but increasingly no-take zones are being shown to provide recruits to adjacent over-fished areas (Pillans et al, 2005;Russ, Alcala, & Maypa, 2003).…”

Ecological and Socio-Economic Effects of Highly Protected Marine Areas (HPMAs) in Temperate Waters

“…Temperate HPMAs have been found to show similar, positive biological responses for reef habitat compared with tropical ones (Stewart et al, 2009;Harasti et al, 2018). Positive biological responses have also been shown to be greater in HPMAs than in areas receiving less protection.…”

“…On average, many fish, invertebrate and seaweed species increase in biomass, density, size and species diversity inside tropical and temperate HPMAs (Lester et al, 2009;Fenberg et al, 2012, Sciberras et al, 2013Edgar et al, 2014, Guidetti et al, 2014Di Franco et al, 2016, Harasti et al, 2018. Some fish and invertebrate species decline inside HPMAs as a result of competitive or predatory interactions (Micheli et al, 2004).…”