Geology topics

Peter J. Mumby

Publications and source records attributed to Peter J. Mumby.

3 recordsLinked to original sources

USGS2018

A framework for identifying and characterising coral reef “oases” against a backdrop of degradation

Human activities have led to widespread ecological decline; however, the severity of degradation is spatially heterogeneous due to some locations resisting, escaping, or rebounding from disturbances. We developed a framework for identifying oases within coral reef regions using long‐term monitoring data. We calculated standardised estimates of coral cover ( z ‐scores) to distinguish sites that deviated positively from regional means. We also used the coefficient of variation (CV) of coral cover to quantify how oases varied temporally, and to distinguish among types of oases. We estimated “coral calcification capacity” (CCC), a measure of the coral community's ability to produce calcium carbonate structures and tested for an association between this metric and z ‐scores of coral cover. We illustrated our z ‐score approach within a modelling framework by extracting z ‐scores and CVs from simulated data based on four generalized trajectories of coral cover. We then applied the approach to time‐series data from long‐term reef monitoring programmes in four focal regions in the Pacific (the main Hawaiian Islands and Mo'orea, French Polynesia) and western Atlantic (the Florida Keys and St. John, US Virgin Islands). Among the 123 sites analysed, 38 had positive z ‐scores for median coral cover and were categorised as oases. Synthesis and applications . Our framework provides ecosystem managers with a valuable tool for conservation by identifying “oases” within degraded areas. By evaluating trajectories of change in state (e.g., coral cover) among oases, our approach may help in identifying the mechanisms responsible for spatial variability in ecosystem condition. Increased mechanistic understanding can guide whether management of a particular location should emphasise protection, mitigation or restoration. Analysis of the empirical data suggest that the majority of our coral reef oases originated by either escaping or resisting disturbances, although some sites showed a high capacity for recovery, while others were candidates for restoration. Finally, our measure of reef condition (i.e., median z ‐scores of coral cover) correlated positively with coral calcification capacity suggesting that our approach identified oases that are also exceptional for one critical component of ecological function.

Florida, Hawaii↗

USGS2017

New interventions are needed to save coral reefs

Since 2014, coral reefs worldwide have been subjected to the most extensive, prolonged and damaging heat wave in recorded history1. Large sections of Australia’s Great Barrier Reef (GBR) bleached in response to heat stress in 2016 and 2017 — the first back-to-back event on record. Such severe coral bleaching results in widespread loss of reef habitat and biodiversity. Globally, we are facing catastrophic decline of these ecosystems, which sustain services valued at around $US 10 trillion per year2, are home to over a million species3, and feed and support the livelihoods of hundreds of millions of people4. Model predictions indicate that mass coral bleaching could become the new norm by 2050 (ref. 5). Critically, even if global warming can be kept within 1.5⁰C above preindustrial levels, shallow tropical seas would warm at least 0.4°C in coming decades, triggering frequent bleaching of the most sensitive habitat-forming coral species6. This outlook poses a time-critical decision challenge for management and conservation. Existing conservation approaches, despite innovative governance arrangements7, could simply become insufficient to protect coral reefs under any expected climate future. Thus, for coral reefs to remain resilient and their services sustained, we argue that new and potentially riskier interventions must be implemented alongside conventional management efforts and strong action to curb global warming. We build the case for this strategy below.

Nature Ecology & Evolution↗

USGS2015

A typology of time-scale mismatches and behavioral interventions to diagnose and solve conservation problems

Ecological systems often operate on time scales significantly longer or shorter than the time scales typical of human decision making, which causes substantial difficulty for conservation and management in socioecological systems. For example, invasive species may move faster than humans can diagnose problems and initiate solutions, and climate systems may exhibit long-term inertia and short-term fluctuations that obscure learning about the efficacy of management efforts in many ecological systems. We adopted a management-decision framework that distinguishes decision makers within public institutions from individual actors within the social system, calls attention to the ways socioecological systems respond to decision makers’ actions, and notes institutional learning that accrues from observing these responses. We used this framework, along with insights from bedeviling conservation problems, to create a typology that identifies problematic time-scale mismatches occurring between individual decision makers in public institutions and between individual actors in the social or ecological system. We also considered solutions that involve modifying human perception and behavior at the individual level as a means of resolving these problematic mismatches. The potential solutions are derived from the behavioral economics and psychology literature on temporal challenges in decision making, such as the human tendency to discount future outcomes at irrationally high rates. These solutions range from framing environmental decisions to enhance the salience of long-term consequences, to using structured decision processes that make time scales of actions and consequences more explicit, to structural solutions aimed at altering the consequences of short-sighted behavior to make it less appealing. Additional application of these tools and long-term evaluation measures that assess not just behavioral changes but also associated changes in ecological systems are needed.

Conservation Biology↗