Camera loggers are increasingly used to examine behavioural aspects of free-ranging animals. However, often video loggers are deployed with a focus on specific behavioural traits utilizing small cameras with a limited field of view, poor light performance and video quality. Yet rapid developments in consumer electronics provide new devices with much improved visual data allowing a wider scope for studies employing this novel methodology. We developed a camera logger that records full HD video through a wide-angle lens, providing high resolution footage with a greater field of view than other camera loggers. The main goal was to assess the suitability of this type of camera for the analysis of various aspects of the foraging ecology of a marine predator, the yellow-eyed penguin in New Zealand. Frame-by-frame analysis allowed accurate timing of prey pursuits and time spent over certain seafloor types. The recorded video footage showed that prey species were associated with certain seafloor types, revealed different predator evasion strategies by benthic fishes, and highlighted varying energetic consequences for penguins pursuing certain types of prey. Other aspects that could be analysed were the timing of breathing intervals between dives and observe exhalation events during prey pursuits, a previously undescribed behaviour. Screen overlays facilitated analysis of flipper angles and beat frequencies throughout various stages of the dive cycle. Flipper movement analysis confirmed decreasing effort during descent phases as the bird gained depth, and that ascent was principally passive. Breathing episodes between dives were short (<1 s) while the majority of the time was devoted to subsurface scanning with a submerged head. Video data recorded on free-ranging animals not only provide a wealth of information recorded from a single deployment but also necessitate new approaches with regards to analysis of visual data. Here, we demonstrate the diversity of information that can be gleaned from video logger data, if devices with high video resolution and wide field of view are utilized.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6151119PMC
http://dx.doi.org/10.7717/peerj.5459DOI Listing

Publication Analysis

Top Keywords

video loggers
8
marine predator
8
predator yellow-eyed
8
yellow-eyed penguin
8
camera loggers
8
field view
8
prey pursuits
8
seafloor types
8
video
5
high definition
4

Similar Publications

Knowledge of how animals respond to weather and changes in their physical environment is increasingly important, given the higher frequency of extreme weather recorded in recent years and its forecasted increase globally. Even species considered to be highly adapted to extremes of weather, as albatrosses are to strong winds, may be disadvantaged by shifts in those extremes. Tracked albatrosses were shown recently to avoid storms and the strongest associated winds.

View Article and Find Full Text PDF

With increasing use of social housing for dairy calves, there is a need to refine housing management practices that influence animal behavior and may affect welfare. Our aim was to assess the effect of pen space allowance on activity patterns and pen space use. Holstein heifer calves were group-housed (n = 6 pens; 5 calves/pen) at 14 d ± 2.

View Article and Find Full Text PDF

Dairy cows have a partial preference to access an outdoor deep-bedded pack, but the effects of continuous access to an outdoor area on estrous behaviors has not been studied. Our objective was to investigate if access to an outdoor open deep-bedded pack improves the expression of estrus behaviors. We enrolled 60 lactating Holstein cows directly after calving and followed them each for 12 weeks.

View Article and Find Full Text PDF

Hidden rivals: the negative impacts of dolphinfish on seabird foraging behaviour.

Biol Lett

August 2024

Graduate School of Environmental Studies, Nagoya University, Furo, Chikusa, Nagoya 464-8601, Japan.

Marine predators often aggregate at the air-sea boundary layer to pursue shared prey. In such scenarios, seabirds are likely to benefit from underwater predators herding fish schools into tight clusters thereby enhancing seabirds' prey detectability and capture potential. However, this coexistence can lead to competition, affecting not only immediate foraging strategies but also their distribution and interspecies dynamics.

View Article and Find Full Text PDF

Identifying prey capture events of a free-ranging marine predator using bio-logger data and deep learning.

R Soc Open Sci

June 2024

Department of Statistical Sciences, Centre for Statistics in Ecology, Environment and Conservation (SEEC), University of Cape Town, Cape Town 7701, South Africa.

Marine predators are integral to the functioning of marine ecosystems, and their consumption requirements should be integrated into ecosystem-based management policies. However, estimating prey consumption in diving marine predators requires innovative methods as predator-prey interactions are rarely observable. We developed a novel method, validated by animal-borne video, that uses tri-axial acceleration and depth data to quantify prey capture rates in chinstrap penguins ().

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!