Following the recent Journal of Animal Ecology Special Feature on biologging, Associate Editor, Steph Januchowski-Hartley takes a look at how research in this and similar methods are affecting the field of applied ecology today.

jane13012-toc-0001-mAdvances in technology have allowed for small electronic loggers and transmitters to be developed not only for biomedical monitoring for humans (think of the tech we can use for monitoring hearts, blood sugar) but also for monitoring the broader animal kingdom and our environments. In ecology, researchers use diverse electronic logging technologies to locate, track, and monitor species, and to evaluate species’ movements, physiology, and behaviour.

In a recent Journal of Animal Ecology Special Feature, researchers from around the world showcase novel developments in biologging – the use of miniaturized animal-attached tags for logging and/or relaying data about an animal’s movements, behaviour, physiology or environment. These studies collectively advance our understanding of animal behavioural ecology, community ecology, and functional ecology, and present approaches for handling large data in relation to statistical ecology. Below, I highlight several studies from the biologging Special Feature under these broader areas of study and share a recent collection of papers from Journal of Applied Ecology that complement the work presented.

In terms of behavioural ecology, Campioni et al. focus on migration; a behaviour that remains poorly understood across most animals. Their study provides evidence for how long-lived animals (such as Cory’s Shearwaters, the focal species in the study) can acquire a migratory strategy. The authors show that young birds follow more exploratory routes than older birds – showing that learning, memory, and experience can play a key role in the development of migration behaviour.

To better understand niche overlap in three species of fulmarine petrels, Dehnhard et al.  combined a large tracking dataset with stable isotope analysis to reveal that generalist foraging strategies can be advantageous in some environments. The observed strategies by the three fulmarine petrels are contrasting to niche partitioning exhibited by other Southern Ocean seabirds and advance our understanding of foraging behaviour in community ecology.

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Biologging in action. Photo: Luca Borger

Related to our understanding of functional ecology are the questions of how and when animals move and how much energy they expend? This can be challenging in field-based research because of the need for prolonged observations. Benoit et al.  addressed this challenge in one way by coupling body acceleration and distance travelled, data collected from biologgers, as a proxy for energy expenditure. Their findings show that in fragmented landscapes, such as those with high road densities, transient phases of dispersal for roe deer are costlier and that those costs are highest primarily at dawn.

Lisovski et al. present a ‘How-To’ guide on using light-based geolocators, a specific biologging technology. This paper shares strategies for effective use of light-based geolocators, and for handling and manipulating resulting data. The authors provide links to online resources, provide data standards, archiving guidelines, and encourage data reporting structures to facilitate ease of sharing and comparison between studies.

To complement the showcase of research on biologging in Journal of Animal Ecology, I wanted to highlight several recently published articles in Journal of Applied Ecology that bring together similar, but different, methods to those presented in the Special Feature to advance our understanding of community and functional ecology [anyone who knows me can also appreciate that I wanted to highlight an article focused on a fish species within this school of studies focused on birds!].

That said, I’ll start with the work of Gamble et al. , who combine a suite of methods, including bird tracking, to determine whether Brown Skuas are involved in the spread of a bacterium that causes avian cholera in other nearby seabird colonies, such as albatross and penguins. By combining moving and epidemiological studies, the authors demonstrated the importance of considering the behaviour and epidemiological status of both predators and scavengers in disease dynamics. They found, through movement data, that Brown Skuas could be spreading the bacterium in question among and within different seabird colonies in their study area, Amsterdam Island. Like the work of Dehnhard et al. Gamble and colleagues demonstrate how linking tracking tools and technologies with methods from other fields of study can help us to better understand complex interactions within and among species.

Infrastructure, such as dams, and those associated with roads, such as culverts, bridges, and fords can impede fish movement between aquatic habitats. Different species abilities to overcome this infrastructure is related to environmental and infrastructure characteristics, as well as the physiology, morphology and behaviour of species and individuals. To better understand links between behavioural and functional ecology, and potential human effects on these, Goerig et al.  carried out an experimental study that depended on transponders to monitor fish movements. The authors tracked brook trout movements and measured morphological characteristics to determine how body shape influenced fish attempt rates to overcome road culverts and their passage success. They found that a ‘streamlined’ body shape was associated with increased motivation to enter and ascend culverts, and to a lesser extent, to the probability of fish successfully passing through the culvert. They also found that the density of other fishes below the culvert, time of day, body size and water velocity influenced motivation to overcome and successfully pass through culverts. Their findings highlight an important connection between individual behaviour and morphological traits, and that human-induced modifications such as culverts, in our waterscapes could interact with those connections to act as agents of selection on behaviour and morphology in different fish populations.

The collection of studies in Journal of Animal Ecology and Journal Applied Ecology provides a broad overview of current knowledge and advances in biologging technology and related tools and methods, as well as some challenges that remain. For example, many studies are single species focused, and there remains limited understanding about how findings from one species or group of related species are transferable to other species, if at all. Finally, as Börger et al. highlight, it is encouraging to see the potential, and value for, creative application and development of biologging methods through collaborations in different areas of ecology and disciplines that will ultimately help us to better understand animal ecology, and how animals are responding and potentially adapting to human-mediated global changes.