Determinants of island ecological complexity in the context of global change

Introduction

Biodiversity is declining globally at an unprecedented rate. Representing ~30% of the biodiversity hotspots, islands are particularly vulnerable to anthropogenic activities; indeed, 80% of reported extinctions are island species.

Importance of Island Biodiversity

Yet, unique island biodiversity, which includes not only the species but also the myriad of interactions among them, is still greatly unknown. It is thus urgent to describe it and forecast the consequences of its annihilation so we can mitigate the effect of further losses.

Challenges in Understanding Ecological Interactions

Detecting ecological interactions and understanding their complexity is, however, one of the big challenges in the natural sciences. The advent of new theories and analytical tools, such as critical transition theory and complex network analysis, provides hope to reach that goal.

Potential of Islands as Study Systems

As relatively simple systems with well-defined borders, islands have great potential to advance our comprehension of nature's complexity.

Project Overview: IslandLife

IslandLife will provide the most comprehensive and quantitatively sophisticated study of multilayer networks to date in any terrestrial ecosystem.

Focus Areas

We will focus on five archipelagos encompassing four oceans and a wide latitudinal gradient, comparing for the first time the food web structure of:

1. Pristine (little-disturbed) islands (of a few km²)
2. Areas of similar size in nearby disturbed (human-inhabited) islands

Objectives

The objective is to:

• Unveil the unique biodiversity of these ecosystems
• Understand their complexity
• Evaluate their fragility to global change drivers, such as biological invasions

Methodology

We will combine:

• Direct observations during intense fieldwork
• Automated-video monitoring and deep learning
• Cutting-edge molecular techniques
• Newly developed coextinction models to predict persistence and resilience of island biota to disturbances

Significance of the Project

The project will represent a major breakthrough towards understanding the effects of global change on these valuable ecosystems, of great relevance to both theoretical ecologists and applied conservationists.