Photogrammetry in rocky temperate marine ecosystems: applications, problems and potential

Photogrammetry has emerged as a transformative tool in marine ecology, enabling the creation of detailed three-dimensional (3D) models of underwater habitats that offer significant advantages over traditional monitoring techniques. While photogrammetry is widely applied in tropical reef environments, its use in temperate systems remains more limited due to logistical, environmental and technical challenges. This review explores the application of photogrammetry in cold-water reef environments using Lough Hyne Marine Nature Reserve (Ireland) as a case study. We detail the technical considerations for equipment selection, image acquisition, lighting strategies and model scaling under low-light, low-visibility conditions. We also highlight other key issues affecting model fidelity, including motion blur, macroalgal movement, sedimentation and reef structural complexity. Through the creation of 3D models, we highlight the potential of photogrammetry to quantify temperate benthic assemblages, track individual organisms over time and estimate parameters such as reef rugosity and animal biomass. Compared to traditional photoquadrats, photogrammetry offers improved spatial coverage and more information, albeit with longer survey and processing times. We discuss future directions, including the potential integration of artificial intelligence (AI), such as convolutional neural networks and 3D segmentation, to enhance data analysis and community classification, along with emerging approaches to depth estimation, simultaneous localisation and mapping (SLAM) and Neural Scene Representations. Despite some technical constraints, photogrammetry is a powerful and increasingly accessible tool for ecological monitoring in temperate systems. With continued development, this methodology has the potential to transform how benthic communities are studied, monitored and managed across cold-water reef environments globally.