TY - JOUR
T1 - Implications of porpoise echolocation and dive behaviour on passive acoustic monitoring
AU - Macaulay, Jamie Donald John
AU - Rojano-Doñate, Laia
AU - Ladegaard, Michael
AU - Tougaard, Jakob
AU - Teilmann, Jonas
AU - Marques, Tiago A.
AU - Siebert, Ursula
AU - Madsen, Peter Teglberg
N1 - Funding: The post-doctoral position for J.D.J.M. was funded by a FNU – Danish Natural Science Research Council grant to P.T.M. This study was also funded by the German Federal Agency for Nature Conservation via the grants “Effects of underwater noise on marine vertebrates” (Cluster 7, Z1.2-53302/2010/14) and “Under Water Noise Effects—UWE” (Project No. FKZ 3515822000). The contribution by T.A.M. was funded under the ACCURATE project (U.S. Navy Living Marine Resources Program, Contract No. N3943019C2176) and CEAUL (funded by FCT—Fundação para a Ciência e a Tecnologia, Portugal, through Project No. UIDB/00006/2020).
PY - 2023/10/2
Y1 - 2023/10/2
N2 - Harbour porpoises are visually inconspicuous but highly soniferous echolocating marine predators that are regularly studied using passive acoustic monitoring (PAM). PAM can provide quality data on animal abundance, human impact, habitat use, and behaviour. The probability of detecting porpoise clicks within a given area ( P ̂ ) is a key metric when interpreting PAM data. Estimates of P ̂ can be used to determine the number of clicks per porpoise encounter that may have been missed on a PAM device, which, in turn, allows for the calculation of abundance and ideally non-biased comparison of acoustic data between habitats and time periods. However, P ̂ is influenced by several factors, including the behaviour of the vocalising animal. Here, the common implicit assumption that changes in animal behaviour have a negligible effect on P ̂ between different monitoring stations or across time is tested. Using a simulation-based approach informed by acoustic biologging data from 22 tagged harbour porpoises, it is demonstrated that porpoise behavioural states can have significant (up to 3× difference) effects on P ̂ . Consequently, the behavioural state of the animals must be considered in analysis of animal abundance to avoid substantial over- or underestimation of the true abundance, habitat use, or effects of human disturbance.
AB - Harbour porpoises are visually inconspicuous but highly soniferous echolocating marine predators that are regularly studied using passive acoustic monitoring (PAM). PAM can provide quality data on animal abundance, human impact, habitat use, and behaviour. The probability of detecting porpoise clicks within a given area ( P ̂ ) is a key metric when interpreting PAM data. Estimates of P ̂ can be used to determine the number of clicks per porpoise encounter that may have been missed on a PAM device, which, in turn, allows for the calculation of abundance and ideally non-biased comparison of acoustic data between habitats and time periods. However, P ̂ is influenced by several factors, including the behaviour of the vocalising animal. Here, the common implicit assumption that changes in animal behaviour have a negligible effect on P ̂ between different monitoring stations or across time is tested. Using a simulation-based approach informed by acoustic biologging data from 22 tagged harbour porpoises, it is demonstrated that porpoise behavioural states can have significant (up to 3× difference) effects on P ̂ . Consequently, the behavioural state of the animals must be considered in analysis of animal abundance to avoid substantial over- or underestimation of the true abundance, habitat use, or effects of human disturbance.
U2 - 10.1121/10.0021163
DO - 10.1121/10.0021163
M3 - Article
AN - SCOPUS:85173220683
SN - 0001-4966
VL - 154
SP - 1982
EP - 1995
JO - Journal of the Acoustical Society of America
JF - Journal of the Acoustical Society of America
IS - 4
ER -
