Predation research with electronic tagging

Abstract

Predation is a fundamental aspect of ecology that drives ecosystem structure and function. A better understanding of predation can be facilitated by using electronic tags that log or transmit positions of predator or prey species in natural settings, however, there are special considerations that must be made to avoid biased estimates. We provide an overview of the tools available for studying predation with electronic tags including the tag types and analytical tools that can be used to identify where, when and how prey are killed by predators. We also discuss considerations for experimental design when studying predation using electronic tags, including how to minimize effects of capture and tagging procedures. Ongoing innovation and integration of sensors for tags will provide more detailed data about the performance of tagged predators and the fate of tagged prey. Where analysts can effectively resolve the timing of predation using stateof-the-art tags and analytical tools, we foresee exciting advances in our understanding of animal demographics, evolutionary trajectories and management systems. Prospects to develop new tools and approaches for tracking predation while designing studies to more effectively limit bias are an important frontier for understanding ecosystems and addressing human-wildlife conflicts. Given great uncertainties about environmental change and intensifying conflicts between humans and predators, effective study designs integrating electronic tagging to study predation have a promising future in fundamental and applied ecology.

Globally coordinated acoustic aquatic animal tracking reveals unexpected, ecologically important movements across oceans, lakes and rivers

“…Additional misinterpretations can be caused by tags being moved by people (e.g. tags from harvested fish deposited around a receiver) or movements of predators; predation can be ascertained with various tags and tools for investigating fish fate in detail (Lennox et al 2023). Acoustic telemetry is limited in scale by how many receivers are deployed and where they are active, because acoustic transmitters can only be detected where receivers are active.…”

Positioning aquatic animals with acoustic transmitters

“…For example, it may be very difficult to discern if the transmitter signals come from the animal that was tagged, or a predator that has ingested the tagged animal. In such cases, predation event data can be very useful, using temperature or predation sensors (Hanssen et al, 2022; Klinard & Matley, 2020; Lennox et al, 2023). If the prey and the predator exhibit different behaviours, information from a pressure or acceleration sensor may allow the identification of predation events (e.g.…”

“…Moreover, a decision key should be used to probabilistically assess the fate of tagged individuals based on objective, repeatable criteria (e.g. Halttunen et al, 2018; Lennox et al, 2023). The timing of the fate event (e.g.…”

Health and environmental effects to wildlife from radio telemetry and tracking devices—state of the science and best management practices

“…Increased vulnerabilities to predators ( 19 , 66 , 67 ) due to a weakened host and other species’ ability to perceive transmitted signals on/in tagged animals, cluing predators to their presence.…”