Sean Eng Howe Pang

and 5 more

The concept of the ecological niche is fundamental to understanding species distributions but it often overlooks the critical role of demography in shaping said distributions. Conversely, demographic theory has traditionally neglected how vital rates vary across environments, limiting our understanding of population dynamics across species’ ranges. Over 50 years ago, Maguire proposed conceptualising the ecological niche as composed of multiple “demographic niches” corresponding to separate vital rates such as survival, development, and reproduction. Despite its potential for ecological research, Maguire’s perspective never really took off. Here, we introduce the “demographic niche concept” (DNC), a contemporary evolution of Maguire’s perspective, integrating recent advances in niche theory and demography to formalise the DNC. We first outline the theoretical foundations of the DNC, focusing on vital rate variation along environmental gradients and its role in shaping ecological niches. We then formalise the definition of the DNC, explore how demographic niches and their boundaries are determined, and introduce a framework for applying the DNC in environmental and geographic spaces. Importantly, we present the DNC as a tool for conservation planning by improving our ability to identify critical areas where specific demographic processes are vital for species persistence or absent under global change. Throughout this review, we also explore methods for modelling and integrating demographic niches and discuss their relevance for addressing global challenges such as climate change. By integrating the ecological niche with demographic theory, we propose testable hypotheses on how and why vital rates vary within niche space, the current frontier of the DNC. Finally, we identify key knowledge gaps and suggest research directions to address these gaps. By advancing the conceptual and methodological tools of the DNC, this review establishes a foundation for future empirical research and applications, offering new directions for ecological theory and conservation amidst a changing world.

Adam Wilson

and 4 more

The Greater Cape Floristic Region (GCFR) of South Africa includes marine and terrestrial biomes with species diversity rivaling mega-diverse tropical rainforests in a compact area (300x700km). Extinction risk studies suggest that GCFR species are among the most vulnerable to climate change over the next 50 years. I present a scoping proposal commissioned by NASA to develop a field campaign to measure and monitor the distribution and abundance of biodiversity with new remotely-sensed data and the rich historical data in this region. I will summarize the central questions to be addressed by this field campaign and lay out the proposed study design to integrate satellite, airborne, and in situ data collection. Our plan centers around the collection of new hyperspectral imagery from AVIRIS-NG, PRISM, and HyTES spectrometers combined with the LVIS laser altimeter. These data will be collected at approximately 20 m spatial resolution across much of the GCFR and nearby aquatic and marine ecosystems. These data will then be combined with existing and new observations of the spatial distribution of community composition and functional traits to enable high resolution mapping and modeling of several essential biodiversity variables (EBVs) including species distributions, functional traits (including leaf properties), and three-dimensional canopy structure. Given the wealth of available independent in situ data available that can be brought to bear, the GCFR is an ideal system to fully evaluate the capabilities of remote-sensing technology to characterize biodiversity patterns across diverse landscapes in a relatively compact geographic area. In combination with the rich historical data and well-developed ecological understanding in this region, these new observations will enable detailed exploration into the drivers and mechanisms of change including the feedbacks from changing biodiversity to regional climate, disturbance, post-fire recovery, freshwater provisioning, and other ecosystem services.