Historical Reconstruction Reveals Recovery in Hawaiian Coral Reefs

Abstract

Coral reef ecosystems are declining worldwide, yet regional differences in the trajectories, timing and extent of degradation highlight the need for in-depth regional case studies to understand the factors that contribute to either ecosystem sustainability or decline. We reconstructed social-ecological interactions in Hawaiian coral reef environments over 700 years using detailed datasets on ecological conditions, proximate anthropogenic stressor regimes and social change. Here we report previously undetected recovery periods in Hawaiian coral reefs, including a historical recovery in the MHI (∼AD 1400–1820) and an ongoing recovery in the NWHI (∼AD 1950–2009+). These recovery periods appear to be attributed to a complex set of changes in underlying social systems, which served to release reefs from direct anthropogenic stressor regimes. Recovery at the ecosystem level is associated with reductions in stressors over long time periods (decades+) and large spatial scales (>103 km2). Our results challenge conventional assumptions and reported findings that human impacts to ecosystems are cumulative and lead only to long-term trajectories of environmental decline. In contrast, recovery periods reveal that human societies have interacted sustainably with coral reef environments over long time periods, and that degraded ecosystems may still retain the adaptive capacity and resilience to recover from human impacts.

Human Dimensions of Coral Reef Social-Ecological Systems

“…Global patterns of decline in coral reef SESs have been documented (Jackson et al 2001, but evidence of recovery and sustainable SES interactions are also emerging (Cinner et al 2009b, Kittinger et al 2011, Lotze et al 2011). The differences in trajectories of SESs highlight the need to understand the human dimensions associated with sustainability or decline.…”

Making the transition to co-management governance arrangements in Hawai‘i: a framework for understanding transaction and transformation costs

“…For example, organized fishing interests heckled crowds and decision makers at public meetings, filed petitions to delay an administrative decision, and lobbied new legislators in an attempt to block approval of rules. Respondents frequently reported that organized interests opposed any rules changes despite documented resource depletion across the Hawaiian archipelago (Friedlander and DeMartini 2002;Kittinger et al 2011;Nadon et al 2015). To overcome strategic costs, community members raised public awareness, lobbied legislators, and encouraged citizens to support their proposals.…”

Fishing and environmental influences on estimates of unfished herbivorous fish biomass across the Hawaiian Archipelago

“…Despite the geographic isolation of the NWHI, anthropogenic influences are present (Selkoe et al 2008), though their magnitude is much less compared to the populated MHI. Over the past century, fishing effort in the N WHI, especially for reef fish, has been relatively low (Kittinger et al 2011), and fishing has been prohibited in the region since 2000. In contrast, fisheries in the MHI have been exploited since AD 1250 with increasing pressure commensurate with a growing population during the last century (Kittinger et al 2011).…”

“…Over the past century, fishing effort in the N WHI, especially for reef fish, has been relatively low (Kittinger et al 2011), and fishing has been prohibited in the region since 2000. In contrast, fisheries in the MHI have been exploited since AD 1250 with increasing pressure commensurate with a growing population during the last century (Kittinger et al 2011). Coral reef fisheries in Hawaii exploit multiple species but especially herbivorous fishes such as parrotfishes and surgeon-fishes (Friedlander & Parrish 1997).…”