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Ecology, management and conservation in natural and modified habitats
RESEARCH ARTICLE (Open Access)

Species-specific spatial and temporal variability in anuran call detection: implications for deploying autonomous recording units

Andrew Hall https://orcid.org/0000-0001-8213-304X A * , Amelia Walcott B , Ali Borrell B , Dale G. Nimmo https://orcid.org/0000-0002-9814-1009 C and Skye Wassens C
+ Author Affiliations
- Author Affiliations

A Gulbali Institute, Charles Sturt University, Albury, NSW 2640, Australia.

B New South Wales Department of Climate Change, Energy, the Environment and Water, 480 Weeroona Road, Lidcombe, NSW 2141, Australia.

C School of Agricultural, Environmental and Veterinary Science, Charles Sturt University, Albury, NSW 2640, Australia.

* Correspondence to: ahall@csu.edu.au

Handling Editor: Adam Stow

Wildlife Research 52, WR24036 https://doi.org/10.1071/WR24036
Submitted: 14 March 2024  Accepted: 20 December 2024  Published: 21 January 2025

© 2025 The Author(s) (or their employer(s)). Published by CSIRO Publishing. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND)

Abstract

Context

Ecosystem assessment using acoustic monitoring technologies can be an efficient method for determining species community composition and breeding activity, but many factors affect the quality of acoustics-data and subsequent level of confidence in derived inferences.

Aims

We aimed to assess variability in detection probabilities of five frog species using autonomous recording units (ARUs) deployed across a single 1 km2 wetland, comprising a lagoon and surrounding area, and subsequently determine the required number of ARUs with 95% confidence in derived presence–absence data.

Methods

Ten ARUs were deployed in two rings around the lagoon’s centroid close to the water’s edge. Occupancy models were used to derive detection probabilities of species calling in the lagoon from data describing the temporal pattern of calling at each site, which were derived using call recognition software.

Key results

Only two of the five target species were detected by all 10 ARUs. All target species’ non-zero ARU detection probabilities varied by a factor of 14, and the coefficients of variation in individual ARU detection probability for each species varied by a factor of seven. Simulations revealed seven or eight ARUs are required to achieve 95% confidence in confirming presence of either of the two species with the highest observed detection probabilities, given they are present and calling. Even with ten deployed ARUs, the probability of successful detection of the other three species known to be calling on any day was less than 40%.

Conclusions

Effective detection was not achieved for all targeted species by several ARUs during a period when hydrology and season suited recruitment activity. Despite all ARUs being deployed at locations favourable for detecting targeted species, stochastic factors drove spatial variability in detection resulting in markedly different data for each ARU and each species.

Implications

Data describing species presence derived from automated recording units may not be representative due to spatiotemporal variability in detection that varies by species. To improve ARU deployment strategies, a priori knowledge of typical detection probabilities and species spatial variability can be used to determine the required number of call recorders for a set level of confidence.

Keywords: ARU, call recorders, community composition, detection probability, frogs, occupancy, phenology, wetland, wildlife management.

References

Anunciação PR, Sugai LSM, Martello F, de Carvalho LMT, Ribeiro MC (2022) Estimating the diversity of tropical anurans in fragmented landscapes with acoustic monitoring: lessons from a sampling sufficiency perspective. Biodiversity and Conservation 31(12), 3055-3074.
| Crossref | Google Scholar |

Balantic C, Donovan T (2019) Dynamic wildlife occupancy models using automated acoustic monitoring data. Ecological Applications 29(3), e01854.
| Crossref | Google Scholar | PubMed |

Bridges AS, Dorcas ME (2000) Temporal variation in anuran calling behavior: implications for surveys and monitoring programs. Copeia 2000(2), 587-592.
| Crossref | Google Scholar |

Brinley Buckley EM, Gottesman BL, Caven AJ, Harner MJ, Pijanowski BC (2021) Assessing ecological and environmental influences on boreal chorus frog (Pseudacris maculata) spring calling phenology using multimodal passive monitoring technologies. Ecological Indicators 121, 107171.
| Crossref | Google Scholar |

Burnham KP, Anderson DR (2002) ‘Model selection and multimodel inference: a practical information–theoretic approach.’ 2nd edn. (Springer–Verlag: New York, N.Y.)

Castro I, De Rosa A, Priyadarshani N, Bradbury L, Marsland S (2019) Experimental test of birdcall detection by autonomous recorder units and by human observers using broadcast. Ecology and Evolution 9(5), 2376-2397.
| Crossref | Google Scholar | PubMed |

Clément M, Shonfield J, Bayne EM, Baldwin R, Barrett K (2021) Quantifying vocal activity and detection probability to inform survey methods for barred owls (Strix varia). Journal of Raptor Research 55(1), 45-55.
| Crossref | Google Scholar |

Cordier JM, Aguilar R, Lescano JN, Leynaud GC, Bonino A, Miloch D, Loyola R, Nori J (2021) A global assessment of amphibian and reptile responses to land-use changes. Biological Conservation 253, 108863.
| Crossref | Google Scholar |

Dorcas ME, Price SJ, Walls SC, Barichivich WJ (2009) Auditory monitoring of anuran populations. In ‘Amphibian ecology and conservation: a hand book of techniques’. (Ed. CK Dodd Jr) pp. 281–298. (Oxford University Press)

Fiske I, Chandler R (2011) Unmarked: an R package for fitting hierarchical models of wildlife occurrence and abundance. Journal of Statistical Software 43(10), 1-23.
| Crossref | Google Scholar |

Furnas BJ, Callas RL (2015) Using automated recorders and occupancy models to monitor common forest birds across a large geographic region. The Journal of Wildlife Management 79(2), 325-337.
| Crossref | Google Scholar |

Haupert S, Sèbe F, Sueur J (2023) Physics-based model to predict the acoustic detection distance of terrestrial autonomous recording units over the diel cycle and across seasons: insights from an Alpine and a Neotropical forest. Methods in Ecology and Evolution 14(2), 614-630.
| Crossref | Google Scholar |

Heard GW, Canessa S, Parris KM (2015) Interspecific variation in the phenology of advertisement calling in a temperate Australian frog community. Ecology and Evolution 5(18), 3927-3938.
| Crossref | Google Scholar | PubMed |

Hoffmann EP, Mitchell NJ (2022) Breeding phenology of a terrestrial-breeding frog is associated with soil water potential: implications for conservation in a changing climate. Austral Ecology 47(2), 353-364.
| Crossref | Google Scholar |

Holloway P, Miller JA (2017) A quantitative synthesis of the movement concepts used within species distribution modelling. Ecological Modelling 356, 91-103.
| Crossref | Google Scholar |

Howard SD, Bickford DP (2014) Amphibians over the edge: silent extinction risk of data deficient species. Diversity and Distributions 20(7), 837-846.
| Crossref | Google Scholar |

Howard K, Durkin L, Scroggie M, Ward K (2023) The Living Murray–turtle and frog condition monitoring in Barmah–Millewa forest. Report for the 2022–2023 survey season. Arthur Rylah Institute for Environmental Research Technical Report Series No. 367, Heidelberg, Victoria. Available at https://www.mdba.gov.au/sites/default/files/publications/barmah-millewa-turtle-and-frog-condition-monitoring-report-2022-2023.pdf

Kalan AK, Mundry R, Wagner OJJ, Heinicke S, Boesch C, Kühl HS (2015) Towards the automated detection and occupancy estimation of primates using passive acoustic monitoring. Ecological Indicators 54, 217-226.
| Crossref | Google Scholar |

Kéry M (2002) Inferring the absence of a species – a case study of snakes. The Journal of Wildlife Management 66(2), 330-338.
| Crossref | Google Scholar |

Khalighifar A, Brown RM, Goyes Vallejos J, Peterson AT (2021) Deep learning improves acoustic biodiversity monitoring and new candidate forest frog species identification (genus Platymantis) in the Philippines. Biodiversity and Conservation 30(3), 643-657.
| Crossref | Google Scholar |

Kissling ML, Lewis SB, Pendleton G (2010) Factors influencing the detectability of forest owls in southeastern Alaska. The Condor 112(3), 539-548.
| Crossref | Google Scholar |

Leseberg NP, Venables WN, Murphy SA, Jackett NA, Watson JEM (2022) Accounting for both automated recording unit detection space and signal recognition performance in acoustic surveys: a protocol applied to the cryptic and critically endangered Night Parrot (Pezoporus occidentalis). Austral Ecology 47(2), 440-455.
| Crossref | Google Scholar |

MacKenzie DI, Nichols JD, Lachman GB, Droege S, Royle JA, Langtimm CA (2002) Estimating site occupancy rates when detection probabilities are less than one. Ecology 83(8), 2248-2255.
| Crossref | Google Scholar |

MacLaren AR, Crump PS, Royle JA, Forstner MRJ (2018) Observer-free experimental evaluation of habitat and distance effects on the detection of anuran and bird vocalizations. Ecology and Evolution 8(24), 12991-13003.
| Crossref | Google Scholar | PubMed |

Mathwin R (2024) The establishment of frog monitoring methods and sites to inform ecological targets of the weir pool manipulation strategy: a report to the Department for Environment and Water, Government of South Australia. Rupert.Mathwin.Ecology, Belair, South Australia.

Melo I, Llusia D, Bastos RP, Signorelli L (2021) Active or passive acoustic monitoring? Assessing methods to track anuran communities in tropical savanna wetlands. Ecological Indicators 132, 108305.
| Crossref | Google Scholar |

Muñoz MI, Halfwerk W (2022) Amplification of frog calls by reflective leaf substrates: implications for terrestrial and arboreal species. Bioacoustics 31(4), 490-503.
| Crossref | Google Scholar |

Penman TD, Lemckert FL, Mahony MJ (2005) A cost-benefit analysis of automated call recorders. Applied Herpetology 2(4), 389-400.
| Crossref | Google Scholar |

R Core Team (2022) ‘R: A language and environment for statistical computing.’ (R Foundation for Statistical Computing: Vienna, Austria) Available at https://www.R-project.org/

Raulings EJ, Morris K, Roache MC, Boon PI (2010) The importance of water regimes operating at small spatial scales for the diversity and structure of wetland vegetation. Freshwater Biology 55(3), 701-715.
| Crossref | Google Scholar |

Schalk CM, Saenz D (2016) Environmental drivers of anuran calling phenology in a seasonal neotropical ecosystem. Austral Ecology 41(1), 16-27.
| Crossref | Google Scholar |

Scott Brandes T (2008) Automated sound recording and analysis techniques for bird surveys and conservation. Bird Conservation International 18(S1), S163-S173.
| Crossref | Google Scholar |

Sugai LSM, Silva TSF, Llusia D, Siqueira T (2021) Drivers of assemblage-wide calling activity in tropical anurans and the role of temporal resolution. Journal of Animal Ecology 90(3), 673-684.
| Crossref | Google Scholar | PubMed |

Swiston KA, Mennill DJ (2009) Comparison of manual and automated methods for identifying target sounds in audio recordings of Pileated, Pale-billed, and putative Ivory-billed woodpeckers. Journal of Field Ornithology 80(1), 42-50.
| Crossref | Google Scholar |

Szantoi Z, Escobedo FJ, Abd-Elrahman A, Pearlstine L, Dewitt B, Smith S (2015) Classifying spatially heterogeneous wetland communities using machine learning algorithms and spectral and textural features. Environmental Monitoring and Assessment 187(5), 262.
| Crossref | Google Scholar | PubMed |

Thomas A, Speldewinde P, Roberts JD, Burbidge AH, Comer S (2020) If a bird calls, will we detect it? Factors that can influence the detectability of calls on automated recording units in field conditions. Emu - Austral Ornithology 120(3), 239-248.
| Crossref | Google Scholar |

Turgeon PJ, Van Wilgenburg SL, Drake KL (2017) Microphone variability and degradation: implications for monitoring programs employing autonomous recording units. [Variabilité et dégradation des microphones: implications pour les programmes de surveillance utilisant des unités d’enregistrement autonomes]. Avian Conservation and Ecology 12(1), 9.
| Crossref | Google Scholar |

Ulloa JS, Aubin T, Llusia D, Courtois ÉA, Fouquet A, Gaucher P, Pavoine S, Sueur J (2019) Explosive breeding in tropical anurans: environmental triggers, community composition and acoustic structure. BMC Ecology 19(1), 28.
| Crossref | Google Scholar | PubMed |

Walls SC, Hardin Waddle J, Barichivich WJ, Bartoszek IA, Brown ME, Hefner JM, Schuman MJ (2014) Anuran site occupancy and species richness as tools for evaluating restoration of a hydrologically-modified landscape. Wetlands Ecology and Management 22(6), 625-639.
| Crossref | Google Scholar |

Wimmer J, Towsey M, Roe P, Williamson I (2013) Sampling environmental acoustic recordings to determine bird species richness. Ecological Applications 23(6), 1419-1428.
| Crossref | Google Scholar | PubMed |