No-take Marine Research Articles

Consistent edge effect patterns revealed using continuous surveys across an Eastern Mediterranean no-take marine protected area

AbstractBecause marine protected areas (MPAs) are not equally effective across their areas, monitoring should progress from dichotomic (within vs. outside) to a finer spatial resolution. Here, we examine the effect of an Eastern Mediterranean no-take MPA on fishes across the MPA and into fished areas, using three methods: underwater visual censuses, acoustic surveys, and towed-diver surveys. The Eastern Mediterranean includes non-indigenous species, so the effect of the MPA was also evaluated for its resistance to invasion. The fine-scale analysis revealed ecological phenomena that could not be captured by dichotomic sampling, such as the edge effect, a reduction of fish biomass along the MPA periphery. Despite their differences, all three methods revealed similar spatial patterns. The fine-scale analysis did not support a biotic resistance of the MPA to non-indigenous species. Our study supports the prevalence of edge effects even in well-enforced no-take MPAs and highlights the need for continuous monitoring to reveal these patterns.

Assessing the carbon storage value of kelp forest restoration in the Hauraki Gulf Marine Park, New Zealand: Lessons from no-take Marine Protected Areas

Anthropogenic CO2 emissions are one of the principal driving forces of climate change. Climate change leads to systematic changes of ecosystems that cause significant impacts on species interactions, ecosystem processes, and result in profound socio-economic consequences. While carbon offsetting of terrestrial forests and their monetary value are well accepted, the carbon offsetting potential and value of coastal and marine ecosystems (Blue Carbon, BC) remains excluded from the international carbon accounting framework. In this study, we estimated the carbon offsetting value of kelp forests (Ecklonia radiata) against urchin barrens (dominated by crustose coralline algae) using the standing stock biomass as a metric. We propose that standing stock biomass is a crucial next step in introducing BC to the general carbon offsetting framework. Our approach is informed by long-term ecological research conducted in a marine reserve, which highlights the potential of utilizing trophic cascades to limit the dominance of urchin barrens in shallow coastal habitats. We found that the value of carbon standing stock in current kelp forests with reforestation in the Hauraki Gulf Marine Park (HGMP) is worth up to $NZ 7.9 million, based on 2021 carbon market pricing in New Zealand. This simple step towards realizing the value of marine conservation and its multiple benefits to society highlights the missed opportunities when policy and plans do not align with ecology and economics. Including the ocean's contributions to carbon storage is a critical step in using monetization techniques to overcome climate change challenges. Monetizing the carbon offsetting value of kelp forests contributes to establishing funding mechanisms to attract diverse investments in marine ecosystem restoration while providing ecological benefits in ocean governance.

Fish community dynamics in a coastal no-take marine protected area compared to a harvested area before and after protection from fishing

Abstract An ecosystem's ability to maintain key functions during environmental change is largely determined by its biodiversity. We compared fish species composition, richness, diversity, catch per unit effort (CPUE), and fish size between a 1.5 km2 no-take marine protected area (MPA) and a nearby fished area on the southern Norwegian coast annually for one decade (2011–2021), including before-protection status. In total, >26 thousand fish representing 31 species were sampled using a beach seine. No significant effect of protection was detected on either species richness, diversity, or evenness. For selected species of small-bodied intermediate predators, there was a significant decline in mean body size in the MPA area compared to the fished area, indicative of a response to protection involving trophic interactions. No significant effect of the MPA was detected on either CPUE or body size of Atlantic cod (Gadus morhua), a top predator mainly captured at the juvenile stage by our sampling. The limited responses seen in this study may be linked to the small size of the MPA compared to the dispersal and movement capabilities of species such as the cod.

Marine reserve use by a migratory coastal shark, Carcharias taurus

Networks of small no-take marine protected areas (MPAs) are a popular approach to protect mobile marine species at key sites along their migration routes. Understanding how individuals vary in their use of these sites is needed to ensure MPA networks are optimised to offer maximum protection benefits. Using diver-led surveys, coded acoustic tags and a continental-scale collaborative network of acoustic receivers, we investigated variation in the use of three Australian MPAs by aggregating grey nurse sharks, Carcharias taurus. The Wolf Rock MPA was used year-round by C. taurus and as a gestation site, with females spending up to 254 d at the site with 2.2–3.7 year absences between residencies. In contrast, Flat Rock and Cherubs Cave-Henderson Rock MPAs were used as a transitory aggregation site with males and females occurring at the site for 30 min–59 d intervals between June–January, only. Migratory movements ranged up to 1500 km along the coastline, intersected 18 MPAs and/or recognised C. taurus aggregation sites, and connected temperate waters at Montague Island (36.25° S) with that of the southern Great Barrier Reef (23.40° S). Our study demonstrates how local receiver arrays and national collaborative acoustic telemetry networks are powerful tools to reveal use, fidelity and connectivity of MPA networks by marine migratory species. As the east Australian C. taurus population is critically endangered and at particular risk of anthropogenic threats, ongoing monitoring of the species' movement behaviour and complementary management outside protected area boundaries is warranted to assist its protection.

Decreased tourism during the COVID-19 pandemic positively affects reef fish in a high use marine protected area.

Humans alter ecosystems through both consumptive and non-consumptive effects. Consumptive effects occur through hunting, fishing and collecting, while non-consumptive effects occur due to the responses of wildlife to human presence. While marine conservation efforts have focused on reducing consumptive effects, managing human presence is also necessary to maintain and restore healthy ecosystems. Area closures and the tourism freeze related to the COVID-19 pandemic provided a unique natural experiment to measure the effects of decreased tourism on fish behavior in a high use no-take marine protected area (MPA) in Hawai`i. We found that when tourism shut down due to COVID restrictions in 2020, fish biomass increased and predatory species increased usage of shallow habitats, where tourists typically concentrate. When tourism resumed, fish biomass and habitat use returned to pre-pandemic levels. These displacement effects change fish community composition and biomass, which could affect key processes such as spawning, foraging and resting, and have knock-on effects that compromise ecosystem function and resilience. Managing non-consumptive uses, especially in heavily-visited MPAs, should be considered for sustainability of these ecosystems.

A dynamic game model for no-take marine reserves

Representing about 8% of the world’s oceans, marine protected areas (MPAs) are effective instruments for mitigating the damage that overfishing can do to ecological and economic systems. Yet, less than 2% of the ocean is proclaimed an exclusive no-take zone. Expecting their number and size to increase significantly in the coming years, meticulous implementation of MPAs is central to their success. Using a dynamic game model we explore the impact of designated no-take marine reserves on fish stock and on fishing strategies. Our findings suggest that optimality can be achieved in a context of a combination of three marine zones, i.e., an open access fishery, a marine protected area and a fish bank. Our methodology consists of considering an infinite time horizon discrete fishing game with a migratory species between the three regions. We analyze fishing strategies and characterize the model equilibria for different behaviors, the fully non-cooperative scheme, the social optimum and the cartel setting. Our analytical results are supported by the use of a numerical simulation that compares different scenarios, including the current state of the world in contrast to different sizes of MPAs and fish bank areas.

Correction to: Conservation benefits of no-take marine reserves outweigh modest benefits of partially protected areas for targeted coral reef fishes

Correction to: Conservation benefits of no-take marine reserves outweigh modest benefits of partially protected areas for targeted coral reef fishes

Limited conservation efficacy of large-scale marine protected areas for Pacific skipjack and bigeye tunas

Large-scale, no-take marine protected areas (MPAs) have been established in several locations in the Pacific and expansion of such areas to reach 30% of the ocean area is actively promoted in some quarters. Justification for the establishment of large oceanic MPAs often includes the conservation benefits that they would bring for tuna stocks, which are the subject of important commercial fisheries in the Pacific. The aim of this paper was to evaluate the conservation efficacy of an existing MPA, the Phoenix Islands Protected Area (PIPA) and a series of large hypothetical MPAs each constituting approximately 33% of the western and central Pacific Ocean, for two important and contrasting tuna species, skipjack and bigeye tuna. The evaluation was conducted by comparing control and counterfactual simulations in which the estimated population and fishery dynamics of the species were modelled using a high-resolution modelling framework known as SEAPODYM (Spatial Ecosystem And Population DYnamics Model). We found that stock-wide conservation benefits of the PIPA for these species, assuming that total fishing effort is maintained, to be weak to non-existent, and only modest increases in spawning biomass of both species occur within and in the near vicinity of the PIPA itself. For the larger 33% hypothetical MPAs, changes in stock-wide spawning biomass were estimated to be -0.1% to +5.8% for skipjack tuna and +4.8% to +12.0% for bigeye tuna. Conservation efficacy of MPAs for species such as tropical tunas is limited by their wide larval dispersal and high mobility of later life stages, which spatially dissipate the protective effects of MPAs. Also, the displacement of fishing effort from MPAs to areas remaining open can have negative consequences for stocks and fisheries performance in those areas. We conclude that large oceanic MPAs are not likely to be effective frontline management tools for tropical tunas and other species having similar life history characteristics.

Conservation benefits of no-take marine reserves outweigh modest benefits of partially protected areas for targeted coral reef fishes

Conservation benefits of no-take marine reserves outweigh modest benefits of partially protected areas for targeted coral reef fishes

Marine protected areas provide unfished reference information to empirically assess fishery status

Fisheries stock assessments typically determine stock-status using estimates of unfished biomass generated from fisheries dependent data. Due to limitations and biases in these data, modelled unfished estimates are reliant on assumptions regarding stock ecology. This can lead to a high degree of uncertainty in estimates of unfished biomass and can compromise sustainable management. We propose using the biomass of exploited species in no-take marine protected areas (marine reserves) as a proxy for unfished biomass to empirically assess stock status. Marine reserves provide contemporary examples of exploited populations in the absence of fishing under current conditions. Using lobster (Jasus edwardsii) potting and diver-based survey data from 2018 and 2019 we calculated fisheries relevant metrics from inside and outside two north-eastern New Zealand marine reserves. Based on marine reserve reference points, we found spawning stock catch rates and biomass of lobster in adjacent fished areas were 3 % and 2 % of unfished levels. Comparability of potting and dive survey estimates validates using dive survey data to estimate stock status, while differences in population information between survey methods highlights the limited ability of catch data to accurately inform on sub-legal abundances. Overall, our fisheries-independent approach suggests the fished population is at lower levels than latest estimates for the wider fishery and demonstrates how marine reserves can provide information on key parameters which can be incorporated into traditional stock assessments. Planning for future marine reserves should consider the value of such areas as tools to help manage fisheries in addition to protecting exploited species.

Piscine predation rates vary relative to habitat, but not protected status, in an island chain with an established marine reserve

Establishing marine reserves can increase biomass and diversity relative to surrounding areas. However, such changes presumably alter species compositions, interactions, and associated demographic processes such as predation. We investigated relative predation pressure by fish inside and outside of a well-established no-take reserve using standardized predation tether units: Squidpops. We deployed Squidpops (N = 990) monitored by cameras to examine predation, as estimated by consumption rates, between paired seagrass and patch reef habitat sites proximate to the Exuma Cays Land and Sea Park, a well-enforced no-take Bahamian reserve since 1986. Surprisingly, there was no significant park effect on consumption nor observed diversity. Significantly higher consumption rates were found at patch reef sites relative to seagrass sites, occurred in association with higher fish diversity and with longer soak times. Observed fish diversity was predicted by habitat and distance inshore with more species found on patch reefs and further from the deep water Exuma Sound. Recorded fish bites were positively associated with patch reef habitat, with reef dwelling fish, and increased as the species became more commonly encountered. Deployment-specific factors, including temperature, depth, and time of day had little impact on measured predation, an expected result as the experiments occurred in similar locations over a fine temporal scale. In our experiment, ecosystem-based factors outweighed the place-based management effects that we expected from being within the oldest well-enforced no-take marine reserve in the Caribbean versus the surrounding actively fished waters. Despite well-documented increases in abundances across trophic levels from primary consumers to apex predators within the reserve, predation rates were not significantly different than adjacent areas. Evaluating the efficacy of a marine reserve in protecting vital ecosystem processes requires studies beyond abundance and diversity surveys. By focusing on predation on two of the most ubiquitous habitats throughout the region and on common species, rather than on exceptional sites and charismatic species, we reveal a process that seems relatively unchanged by strict marine conservation management.

Recreational fishing pressure impacts the density and behaviour of the western rock lobster (Panulirus cygnus, George): evidence from small, no-take marine reserves

Abstract It is unknown whether lobster behaviour is sensitive to fishing, as has been previously suggested for fish. This study investigated the impacts of recreational fishing on the wariness of western rock lobster (Panulirus cygnus, George) through comparisons between fished sites and no-take reserves (NTRs) at Rottnest Island. We used visual census to survey the density and size structure of lobster at sites inside and outside three comparable NTRs, and baited remote underwater video to study the behaviour of lobster at comparable sites. The density of legal-sized P. cygnus was twice as high within NTRs (0.34 ± 0.05) than fished sites (0.16 ± 0.03). P. cygnus also spent less time with bait in fished sites (0.42 ± 0.15 min) than NTRs (1.15 ± 0.28 min). This study provides the first evidence that behaviour of decapods, namely P. cygnus, is sensitive to noninjury-related disturbance associated with recreational fishing, with higher wariness in fished areas. Investigation is required into potentially confounding biotic and abiotic factors to further explore the applicability of lobster wariness as an indicator for fishing pressure.

Spillover-mediated harvesting competition: Effects of fishing ground configuration on fisheries targeting transboundary species.

Overfishing is the main threat to sustainable fisheries and the loss of marine biodiversity. The race-to-fish phenomenon is a central driver of overfishing, and it prevails from small-scale to large-scale management regardless of whether spatial-right-based fisheries management has been implemented to ensure the ownership of fishery resources. In practice, the fishing grounds of resource users create complex configurations. Systematic understanding of harvesting competition across these configurations is necessary to promote sustainable fisheries management. Here, we developed a spatially-explicit model to analyze various scenarios of harvesting competition between two user groups using a game-theoretic approach. We found that realized harvesting competition was largely determined by the configuration of fishing grounds and an ecological mechanism where the ecological rescue effect could escalate harvesting competition, leading to a low population size. Our results also suggested that the implementation of voluntary no-take marine protected areas could largely mitigate harvesting competition. This suggests that the coordination of user groups is essential to resolve the race-to-fish.

Nearshore marine biodiversity of Osa Peninsula, Costa Rica: Where the ocean meets the rainforest.

Osa Peninsula in remote southwest Costa Rica harbors 2.5% of global terrestrial biodiversity in only 1,200 km2 and has the largest remaining tract of Pacific lowland wet forest in Mesoamerica. However, little is known about the marine ecosystems of this diverse region. Much of the coastline consists of soft sediment exposed to strong wave action. Three major hard bottom habitat types define this region, including: 1) coral reefs around Isla del Caño Biological Reserve, a no-take marine protected area (MPA) of 52 km2, 2) coastal rocky reefs and islets along the peninsula, including Corcovado National Park, and 3) submerged pinnacles just outside the Isla del Caño MPA. Average coral cover at Isla del Caño was 21%, composed primarily of Porites lobata and Pocillopora elegans. In contrast, coastal rocky reefs were dominated by turf algae (39.8%) and macroalgae (20.7%) with low coral cover (1.1%). Submerged pinnacles were dominated by crustose coralline algae (33.3%) and erect coralline algae (25.7%). Fish assemblage characteristics (species richness, abundance, biomass) were significantly higher at the pinnacles compared to the other habitats and was dominated by schooling species such as Haemulon steindachneri, and the herbivores Kyphosus ocyurus, and Acanthurus xanthopterus. Top predators, primarily Triaenodon obesus, Caranx sexfasciatus, and Lutjanus argentimaculatus, were also most abundant at these pinnacles and accounted for the largest differences in fish trophic structure among habitats. Despite Isla del Caño being fully protected from fishing, biomass was similar to fished areas along the coast and lower than the adjacent submerged pinnacles outside the reserve. Similarly, Corcovado National Park includes 20.3 km2 of no-take MPAs; however, there is limited enforcement, and we noted several instances of fishing within the park. The unique configuration of healthy offshore coral reefs and pinnacles connected to coastal habitats provides corridors for many species including large predators such as sharks and other marine megafauna, which warrants additional protection.

Recreational Fishing Impacts in an Offshore and Deep-Water Marine Park: Examining Patterns in Fished Species Using Hybrid Frequentist Model Selection and Bayesian Inference

No-take marine reserves are often located in remote locations far away from human activity, limiting perceived impact on extractive users but also reducing their use for investigating impacts of fishing. This study aimed to establish a benchmark in the distribution of fished species across the Ningaloo Marine Park – Commonwealth (NMP-Commonwealth), and adjacent comparable habitats within the Ningaloo Marine Park - State (NMP-State), in Western Australia to test if there was evidence of an effect of recreational fishing, as no commercial fishing is allowed within either marine park. We also examined whether the remote location of the newly established (2018) No-take Zone (NTZ), in NMP-Commonwealth, limits its use for studying the effects of fishing. Throughout the NMP-Commonwealth and NMP-State, where recreational fishing is permitted, we expected the abundance of recreationally fished fish species to increase with increasing distance to the nearest boat ramp, as a proxy of recreational fishing effort. Conversely, we did not expect the abundance of non-fished species and overall species richness to vary in response to the proxy for human activity. Distance to the nearest boat ramp was found to be a strong predictor of fished species abundance, indicating that the effect of recreational fishing can be detected across the NMP-Commonwealth. The effect of the NTZ on fished species abundance was weakly positive, but this difference across the NTZ is expected to increase over time. Habitat composition predictors were only found to influence species richness and non-fished species abundance. This study suggests a clear footprint of recreational fishing across the NMP-Commonwealth and as a result the new NTZ, despite its remote location, can act as a control in future studies of recreational fishing effects.

Prohibiting spearfishing boosts conservation outcomes for partially protected areas

Partially Protected Areas (PPAs) are a ubiquitous management tool, yet their ecological effects are often poorly understood. Here, we compare conservation outcomes for two different kinds of PPAs (allowing limited line fishing, but with or without spearfishing) on sheltered and exposed sides of coral reefs of the southern Great Barrier Reef. Compared with No-Take Marine Reserves (NTMRs), Conservation Park Zones (CPZs; spearfishing allowed), had lower biomass and density of primary fisheries targets. Conversely, Special Management Areas (SMAs; spearfishing prohibited) had similar biomass and density of primary targets to NTMRs, and had greater densities of coral trout (a key fishing target), compared to CPZs. No zoning patterns occurred for non-target species. Both PPA zones supported greater biomass of targets compared to less regulated Habitat Protection Zones, which have more allowable fishing activities. These results indicate that partial protection measures limiting fishing activities can create conservation outcomes for targeted fishes. In particular, we provide evidence to support the premise that prohibition of spearfishing can significantly boost conservation outcomes for PPAs. Zoning outcomes did not differ between exposed and sheltered sides of reefs, despite exposed sites consistently supporting a greater biomass and density of fishes. The success of PPAs, and in particular SMAs, in the region is likely due to a combination of factors including: strong enforcement and subsequent compliance of fishing restrictions, the presence of adjacent effective NTMRs, and a long duration of protection. Our results highlight the valuable contributions that PPAs can make to conservation outcomes in well managed MPAs.

Habitat and Marine Reserve Status Drive Reef Fish Biomass and Functional Diversity in the Largest South Atlantic Coral Reef System (Abrolhos, Brazil)

The effects of fishing have been documented across coral reefs worldwide. No-take marine reserves do not only act as a conservation tool but also allow an opportunity to study impacts of fishing, by acting as control sites. In addition, well-planned and well-managed no-take marine reserves (NTRs) provide conservation benefits that are essential to marine biodiversity and ecosystem-based management. The Abrolhos Marine National Park, off the tropical Brazilian coast, protects part of the largest coral reef system in the South Atlantic. To investigate the effects of fishing on reef fish richness, abundance, biomass, and functional diversity of the fish assemblage, we compared sites across two protection levels considering the variation in habitats (Fringing Reefs—Protected; Pinnacles Reefs—Protected; and Coastal Reefs—Open Access), using Baited Remote Underwater Stereo-Video systems (stereo-BRUVs). We adjusted generalized additive mixed models of fish assemblage characteristics with protection levels and environmental variables, such as topographic complexity (mean relief and relief variation), visibility, and benthic cover percentage. Inside NTRs, we found higher total biomass and biomass of fishery target species and carnivores, specifically for the Carcharhinidae (sharks) and Epinephelidae (groupers) families, indicating direct fisheries effects on these groups. In contrast, the ecological parameters of non-target fish were positively correlated with habitat characteristics, including mean relief and variance of relief. Moreover, fish functional diversity was higher within NTRs, demonstrating an even distribution of functional entities. The presence of large mobile predators and the overall higher biomass of carnivores inside the NTR indicate the effect of fishing exclusion. Our results point to the value of NTRs to study the effects of fishing and achieve biodiversity conservation and suggest the importance of using remote sampling methods to assess large mobile predators.

External fishing effort regulates positive effects of no-take marine protected areas

Marine protected areas (MPAs) have been established across the globe to mitigate the effects of multiple stressors on marine communities. In many locations, MPAs have generated positive effects on fish communities, but the impacts of fishing pressure—the primary stressor MPAs seek to manage—have not been well investigated. We examined changes in fish biomass inside and outside of no-take MPAs over 14 years in central California, USA. Using data from the community-based science program, the California Collaborative Fisheries Research Program, we tested which environmental and human-induced stressors most influence the strength of MPA responses. While temperature and productivity were included in the best fit model, we found that fine-scale fishing effort data, following reserve implementation, best explained the spatial variation in fish community responses to MPAs. Specifically, differences in fish biomass between MPAs and sites open to fishing were larger for reserves near heavily fished locations and these areas exhibited the highest rate of change in fish biomass, indicating strong positive effects of the MPA on the most heavily exploited fish communities. As MPAs continue to be used as a prominent conservation strategy in coastal systems, managers should consider both the suite of human-induced (socio-ecological interactions) and environmental conditions that may alter MPA success as well as establish long-term monitoring programs to fully assess the functionality of marine reserves into the future.

Greater resilience of reef fish assemblages in a no-take reserve compared to multi-use areas of the Gulf of California

Conservation strategies, such as the establishment of Marine Protected Areas (MPAs), aim to safeguard biodiversity and to promote resilience of ecosystems by increasing their capacity to maintain key functions and processes following disturbance. However, the extent to which ecosystems in MPAs exhibit resilience remains debated. To address this question, we evaluated changes in reef fish species and functional diversity over time in relation to environmental and anthropogenic disturbances at multiple locations in the Gulf of California, Mexico. From 2005 to 2017, we assessed reef fish species richness and abundance in three MPAs: one no-take marine reserve (Cabo Pulmo) and two multi-use marine protected areas (MUMPAs: Espíritu Santo and Loreto). To examine change in functional diversity and composition, we calculated three functional diversity indices – functional richness, functional dispersion and functional originality – using six biological traits (size, mobility, period of activity, gregariousness, water column position, and diet). Species richness, density and functional diversity were maintained over time (resilience) in the no-take marine reserve. In contrast, MUMPAs showed temporal decline in species richness, which translated into decreases in functional richness and increases in functional dispersion. These differences were also observed at the species level: in Cabo Pulmo, only two ‘loser’ species declined in density, while Espíritu Santo and Loreto showed declines of 12 and 17 species, respectively. The two MUMPAs also shared 9 of the total 22 ‘loser’ species, which are generally abundant and common in the Gulf of California. Density declines were attributed to the combined effect of environmental (sea surface temperature and Chlorophyll-a anomalies) and anthropogenic (fishing, tourism and coastal population density) disturbances. Given the regional decline and the ecological importance of dominant species, long-term decreases in their populations can profoundly modify processes and reef ecosystem services in this region. Thus, local management strategies should be implemented to try to reverse the observed recent decline in fish diversity in MUMPAs.

Valuing Marine Reserves: A case study from two locations in central New Zealand

Marine protected areas such as full no-take marine reserves (MRs) supply numerous ecosystem goods and services, and also deliver conservation and biodiversity benefits, but there are few studies reporting how much the general public values MRs and what factors influence their Willingness to Pay (WTP) for MR management and protection. This study uses Contingent Valuation Method to estimate the WTP of nearby residents for management of two New Zealand MRs (Taputeranga and Kapiti). A total of 360 questionaries were completed (TMR = 262 and KMR = 98). Respondents were asked if they would contribute an annual levy to fund MR management. The annual median WTP values per household were NZ $22.50 (TMR) and NZ $16.88 (KMR). This analysis showed that respondent with children (TMR) or belonging to a group (KMR) are more willing to contribute to the levy. Age is an explanatory variable for WTP amount at both MRs. Respondents ranked seven options for how funds provided via the annual levy should be used; At both MRs more surveillance to reduce fishing at MRs boundaries, and clearing the beach of litter, were ranked highest. This article provides clear evidence that respondent households attach significant value to MRs located on the coast of their city. Findings of this research may be used by the New Zealand Department of Conservation to help prioritise its spending for the maintenance of existing MRs.