Aaron Eger

UNSW Sydney | UNSW · School of Biological, Earth and Environmental Sciences (BEES)

Kelp forests and urchin barrens are two stable states in rocky reef ecosystems, each providing unique ecosystem functions like habitat for marine species and primary production. While studies frequently show that kelp forests support higher levels of some ecosystem functions than urchin barren habitats, no research has yet compared average differen...

The United Nations has declared 2021–2030 as the Decade on Ecosystem Restoration and the Decade of Ocean Science for Sustainable Development. These declarations emphasise the importance of restoring degraded marine and coastal ecosystems and supporting research and knowledge. The number and scale of marine and coastal restoration projects have been...

Essential for healthy oceans, coastal communities, fisheries, economies, and marine biodiversity from the subtropics to the polar regions, kelp forests are an integral and threatened ocean ecosystem. Their benefits are connected to over 740 million people who live beside a kelp forest, and their economic potential is valued at least 500 billion USD...

Marine kelp forests cover 1/3 of our world's coastlines, are heralded as a nature-based solution to address socio-environmental issues, connect hundreds of millions of people with the ocean, and support a rich web of biodiversity throughout our oceans. But they are increasingly threatened with some areas reporting over 90% declines in kelp forest c...

Today, all ecosystems are undergoing environmental change due to human activity, and in many cases the rate of change is accelerating due to climate change. Consequently, conservation programs are increasingly focused on the response of organisms, populations, and ecosystems to novel conditions. In parallel, the field of conservation biology is dev...

While marine kelp forests have provided valuable ecosystem services for millennia, the global ecological and economic value of those services is largely unresolved. Kelp forests are diminishing in many regions worldwide, and efforts to manage these ecosystems are hindered without accurate estimates of the value of the services that kelp forests pro...

The Kelp Forest Alliance (kelpforestalliance.com) was born from a desire to accelerate kelp forest ecosystem restoration across the world by building a global community of practice to enhance information sharing and collaboration. We are achieving this goal using multiple approaches, including reviewing available data on kelp restoration, establish...

This chapter introduces kelp forests, their ecology, and the core themes of kelp forest restoration knowledge and practice. It also provides an overview of how this guidebook is laid out, how it may be used, and introduces the Kelp Forest Alliance, which is an online platform and network for researchers and practitioners to collaborate and share th...

In this chapter we describe the approaches available for kelp restoration and emphasize that you will need to consider the best suited approach(es) for your particular project (Fig. 5.1). The selected methodology will depend on the expertise of your group, project budget, the stressors present, environmental conditions, and whether kelp can return...

Synopsis: This chapter details the first actionable steps to restore kelp forest habitat. It starts by focusing on planning and assessing feasibility for restoration, including identifying objectives and appropriate methods, permitting and biosecurity, and site selection; it then outlines project monitoring and evaluating measures of success, along...

Despite a relatively long history in places like Japan, Korea, and California, the science and practice of kelp forest restoration is still in its infancy, and there remains a wealth of knowledge to be learned and shared from our collective failures and successes. To date, many projects have remained disconnected and had limited opportunities to sh...

The human response to the COVID-19 pandemic set in motion an unprecedented shift in human activity with unknown long-term effects. The impacts in marine systems are expected to be highly dynamic at local and global scales. However, in comparison to terrestrial ecosystems, we are not well-prepared to document these changes in marine and coastal envi...

Kelp forest ecosystems and their associated ecosystem services are declining around the world. In response, marine managers are working to restore and counteract these declines. Kelp restoration first started in the 1700s in Japan and since then has spread across the globe. Restoration efforts, however, have been largely disconnected, with varying...

Marine ecosystems have been used, impacted by, and managed by human populations for millennia. As ecosystem degradation has been a common outcome of these activities, marine management increasingly considers ecosystem restoration. Currently, there is no coherent data recording format or framework for marine restoration projects. As a result, data a...

Biodiversity and ecosystem function are often correlated, but there are multiple hypotheses about the mechanisms underlying this relationship. Ecosystem functions such as primary or secondary production may be maximized by species richness, evenness in species abundances, or the presence or dominance of species with certain traits. Here, we combine...

Kelp forest ecosystems and their associated ecosystem services are declining around the world. In response, marine managers are working to restore and counteract these declines. Kelp restoration first started in the 1700s in Japan and since then has spread across the globe. Restoration efforts, however, have been largely disconnected, with varying...

Underwater kelp forests have provided valuable ecosystem services for millennia. However, the global economic value of those services is largely unresolved. Kelp forests are also diminishing globally and efforts to manage these valuable resources are hindered without accurate estimates of the services kelp forests provide to society. We present the...

The United Nations General Assembly calls for ecosystem restoration to be a primary intervention strategy used to counter the continued loss of natural habitats worldwide, while supporting human health and wellbeing globally. Restoration of coastal marine ecosystems is perceived by many to be expensive and prone to failure, in part explaining its l...

Kelps form extensive underwater forests that underpin valuable ecosystem goods and services in temperate and polar rocky coastlines worldwide. Stressors such as ocean warming and pollution are causing regional declines of kelp forests and their associated services worldwide. Kelp forest restoration is becoming a prominent management intervention, b...

Kelps form extensive underwater forests that underpin valuable ecosystem goods and services in temperate and polar rocky coastlines globally. Stressors, such as ocean warming and pollution are causing regional declines of kelp forests and their associated services worldwide. Kelp forest restoration is becoming a prominent management intervention, b...

Predators can exert top-down control on lower trophic levels, such that their removal or addition may trigger trophic cascades. Despite coastal ecosystems containing well known trophic cascades, there remains uncertainty about the abiotic and biotic factors governing the occurrence and strength of these cascades. Here, we sought to explain the vari...

Kelp forests are highly productive foundation species along much of the world’s coastline. As a result, kelp are crucial to the ecological, social, and economic well-being of coastal communities. Yet, due to a combination of acute and chronic stressors, kelp forests are under threat and have declined in many locations worldwide. Active restoration...

Predators, which are essential to the ecological and economic functioning of marine ecosystems, often exert top-down control on lower trophic levels, such that their removal can trigger trophic cascades. Here, we use a meta-analytic approach, building from earlier syntheses to better understand trophic cascades in marine benthic ecosystems. Our met...

Operation Crayweed focuses on the restoration of underwater forests that disappeared from the coastline of Sydney, Australia’s largest city, 40 years previously. We show how a combination of science, hands‐on restoration, community engagement and art has helped the project to reach its goals as well as raise awareness about the importance of underw...

Biodiversity frequently increases ecosystem function, but there are multiple divergent hypotheses about the mechanisms underlying this relationship. Functions such as primary or secondary production may be maximized by species richness, evenness in species abundances, or the presence or dominance of species with particular traits. Here, we used sur...

Anthropogenic activities have led to the biotic homogenization of many ecological communities, yet in coastal systems this phenomenon remains understudied. In particular, activities that locally affect marine habitat-forming foundation species may perturb habitat and promote species with generalist, opportunistic traits, in turn affecting spatial p...

We found the predictive accuracy of species distribution models (SDMs) for sedentary marine invertebrates to be dependent on the methodology of their application. We explored three applications of SDMs: first a model tested at a scale smaller than at which it was trained (downscaled), second a model tested at scale larger than its training scale (u...