GREAT BARRIER REEF
// Outlook Report 2014
Resilience refers to the capacity of a system to resist disturbance and undergo change while still retaining essentially the same function, structure, integrity and feedbacks.1 It is not about a single, static state, but rather the capacity of an ever-changing, dynamic system to return to a healthy state after a disturbance or impact.2,3,4 It is a concept that is applied to both natural and social systems — from habitats and species, to communities, businesses and social assets. Resilience and vulnerability are related concepts.5,6,7 Resilience (sensitivity and adaptive capacity) is a way of describing the properties of a system and how it responds to exposure to disturbance. Together with exposure, resilience helps determine a system’s overall vulnerability. In the Outlook Report 2009, the resilience of the Great Barrier Reef ecosystem was assessed, including through a series of case studies examining recovery after disturbance. In this report, the assessment is expanded to include the resilience of heritage values, also including some case studies. Each case study contains an introduction, a description of current management arrangements and evidence for recovery.
8.2 Ecosystem resilience
Outlook Report 2009: Overall summary of (ecosystem) resilience
... The vulnerabilities of the ecosystem to climate change, coastal development, catchment runoff and some aspects of fishing mean that recovery of already depleted species and habitats requires the management of many factors. In some instances, the ecosystem’s ability to recover from disturbances is already being compromised with either reduced population growth or no evidence of recovery. ... many of the management measures employed in the Great Barrier Reef Region and beyond are making positive contributions to resilience (as evidenced by recovery of some species and habitats). The Zoning Plans for both the Great Barrier Reef Marine Park and the adjacent Great Barrier Reef Coast Marine Park that were introduced in 2004 are the most significant action taken to enhance biodiversity protection. They provide a robust framework for management and are already demonstrating positive results. Compliance with and public support for these and other measures is a critical factor in building the resilience of the ecosystem. Taken together, available information indicates that the overall resilience of the Great Barrier Reef ecosystem is being reduced. Given the effectiveness of existing protection and management in addressing the most significant pressures on the ecosystem (principally arising from outside the Region), this trend is expected to continue.
Tropical marine ecosystems such as the Great Barrier Reef, and the coastal ecosystems that support them, are subject to a wide range of natural and human-related threats that may damage their components. These ecosystems are resilient if, given sufficient time, they are able to resist or recover from those threats, and maintain key functions without changing to a different state. Understanding the capacity of the Great Barrier Reef ecosystem to resist and recover from the broad range of threats and disturbances it is facing is crucial to improving its long-term protection.7,8,9,10,11 There is no comprehensive information on the ecosystem resilience of the Great Barrier Reef Region (the Region), largely due to the vast extent and complexity of the ecosystem, and because resilience is a complex, dynamic property that is difficult to measure. Therefore, this Reef-wide assessment is necessarily broad. It is based on an overall understanding of resilience; evidence presented in previous chapters on the biodiversity and health of the ecosystem, the impacts facing the Region and the effectiveness of management; and some case studies of recovery.
A resilient system can resist pressures and return to a healthy state.