Linking population effects to animal movements

DEPONS was developed to make it possible to simulate how the North Sea harbour porpoise population is influenced by windfarm construction noise. Noise influences individual animals by scaring them away, which causes them to forage less. This may influence their survival and reproduction, and potentially the population size. The effect of building windfarms in different areas can be tested using DEPONS, which makes it possible to minimize the negative impacts of offshore constructions.

Carefully calibrated for porpoises – but flexible

The current version of DEPONS simulates how harbour porpoises (Phocoena phocoena) respond to pile-driving activities in the North Sea, making it possible to test population consequences of wind farm construction scenarios. But the model can also be calibrated to assess the impacts of other disturbances for other species and in other areas.

The project that made development of DEPONS possible

DEPONS was developed by a team of researchers at Aarhus University as part of the DEPONS project. The objective of the project was both to extend an earlier model developed for the inner Danish waters to simulate population effects of pile-driving in the North Sea, and also to obtain field data to ensure that all aspects of the model were simulated realistically. This included collection of porpoise movement data, analysis of aerial survey data and observations of how porpoises responded to construction noise.

DEPONS literature

Stalder D, van Beest FM, Sveegaard S, et al (2020) Behavioural state modelling of long-term harbour porpoise movement data and the influence of environmental variability. Mar Ecol Prog Ser. doi:10.3354/meps13412
van Beest FM, Teilmann J, Hermannsen L, Galatius A, Mikkelsen L, Sveegaard S, et al. Fine-scale movement responses of free-ranging harbour porpoises to capture, tagging and short-term noise pulses from a single airgun. R Soc Open Sci. 2018;5: 170110. doi:10.1098/rsos.170110
van Beest FM, Teilmann J, Dietz R, Galatius A, Mikkelsen L, Stalder D, et al. Environmental drivers of harbour porpoise fine-scale movements. Mar Biol. 2018;165: 95. doi:10.1007/s00227-018-3346-7
Nabe-Nielsen J, van Beest FM, Grimm V, Sibly RM, Teilmann J, Thompson PM. Predicting the impacts of anthropogenic disturbances on marine populations. Conserv Lett. 2018;11: e12563. doi:10.1111/conl.12563
Tougaard J, Dähne M. Why is auditory frequency weighting so important in regulation of underwater noise? J Acoust Soc Am. 2017;142: EL415–EL420. doi:10.1121/1.5008901
Dähne M, Tougaard J, Carstensen J, Rose A, Nabe-Nielsen J. Bubble curtains attenuate noise from offshore wind farm construction and reduce temporary habitat loss for harbour porpoises. Mar Ecol Prog Ser. 2017;580: 221–237. doi:10.3354/meps12257
Nabe-Nielsen J, Harwood J. Comparison of the iPCoD and DEPONS models for modelling population consequences of noise on harbour porpoises. 2016. Available:
Gilles A, Viquerat S, Becker EA, Forney KA, Geelhoed SC V., Haelters J, et al. Seasonal habitat-based density models for a marine top predator, the harbor porpoise, in a dynamic environment. Ecosphere. 2016;7: e01367. doi:10.1002/ecs2.1367
Cartwright SJ, Bowgen KM, Collop C, Hyder K, Nabe-Nielsen J, Stafford R, et al. Communicating complex ecological models to non-scientist end users. Ecol Modell. 2016;338: 51–59. doi:10.1016/j.ecolmodel.2016.07.012
van Beest FM, Nabe-Nielsen J, Carstensen J, Teilmann J, Tougaard J. Disturbance effects on the harbour porpoise population in the north sea (DEPONS): status report on model development. 2015.
Hermannsen L, Tougaard J, Beedholm K, Nabe-Nielsen J, Madsen PT. Characteristics and propagation of airgun pulses in shallow water with implications for effects on small marine mammals. Miller PJO, editor. PLoS One. 2015;10: e0133436. doi:10.1371/journal.pone.0133436
Nabe-Nielsen J, Sibly RM, Tougaard J, Teilmann J, Sveegaard S. Effects of noise and by-catch on a Danish harbour porpoise population. Ecol Modell. 2014;272: 242–251. doi:10.1016/j.ecolmodel.2013.09.025
Sibly RM, Grimm V, Martin BT, Johnston ASA, Kułakowska K, Topping CJ, et al. Representing the acquisition and use of energy by individuals in agent-based models of animal populations. Murrell D, editor. Methods Ecol Evol. 2013;4: 151–161. doi:10.1111/2041-210x.12002
Nabe-Nielsen J, Tougaard J, Teilmann J, Lucke K, Forchhammer MC. How a simple adaptive foraging strategy can lead to emergent home ranges and increased food intake. Oikos. 2013;122: 1307–1316. doi:10.1111/j.1600-0706.2013.00069.x
Nabe-Nielsen J, Tougaard J, Teilmann J, Sveegaard S. Effects of wind farms on harbour porpoise behavior and population dynamics. Danish Centre for Environment and Energy, Aarhus University; 2011.