DOI: 10.5061/dryad.hqbzkh1vg
title: Data from: Wildlife detection dogs effectively survey a terrestrial amphibian, but differ among individuals, weather and habitat

description: The endangered natterjack toad (Epidalea calamita) faces ongoing habitat
 loss, requiring effective conservation measures. Field surveys must
 therefore address their highly variable detectability in terrestrial
 habitats. We investigated the factors influencing capture success
 comparing two methods: artificial cover boards (ACB) and wildlife
 detection dogs (WDD). We first analysed environmental and training factors
 influencing toad detectability for four detection dogs with varying
 experience using a binomial generalized linear model (GLM). Then, we
 compared capture success of ACBs and WDD transects (deploying two dogs)
 considering weather and habitat type using negative binomial
 GLMs. Across 200 tests, each detection dog displayed a unique
 learning curve, with performance influenced mainly by dog behaviour, wind,
 test blindness and insect presence. Detection rates across dogs levelled
 off at 87.2 % (75.7 % – 94.8 %). Capture success of both methods
 under real-deployment conditions was separately analysed for juvenile and
 (sub-)adult toads by calculating a success rate. For juvenile toads,
 capture success was primarily influenced by capture method, habitat type
 and study year, while adult toads capture success mainly depended on
 habitat type and precipitation. Overall, WDDs (mean rate juvenile toads =
 4.15, mean rate adult toads = 5.61) showed higher success rates than ACBs
 (mean rate juvenile toads = 0.51, mean rate adult toads = 4.73),
 particularly in dense and versatile habitats. This study provides
 practical guidance for the selection and implementation of survey methods
 for E. calamita, identifying critical factors to consider when designing a
 study to maximise survey success. Dog handlers should be able to adapt
 search and training strategies to their dogs’ individual pace and
 limitations and keep environmental influences in mind. Both ACBs and WDDs
 are suitable methods for detecting E. calamita in terrestrial habitats,
 however, detection dogs are particularly useful in densely vegetated
 areas, for finding juveniles and for covering larger regions more
 efficiently. Success rates for adult toads increase in favourable habitat
 and climatic conditions, such as warmer temperatures and sufficient
 moisture. Our findings provide a framework that may be extended to the
 monitoring and conservation of other amphibian species.
description: # Wildlife detection dogs effectively survey a terrestrial amphibian, but
 differ among individuals, weather and habitat Authors: Koch, Veronika
 Paulina (a,b); Bolte, Leonard (a,c); Harms, Wiebke (a,b); Henle, Klaus
 (a); Grimm-Seyfarth, Annegret (a,b) a - UFZ – Helmholtz Centre for
 Environmental Research, Department of Conservation Biology, Permoserstr.
 15, 04318 Leipzig, Germany b - Wildlife Detection Dogs e.V., Immenkorv 19,
 24582 Bordesholm, Germany c - University of Leipzig, Institute of Biology,
 Molecular Evolution and Systematics of Animals, Talstrasse 33, 04103
 Leipzig, Germany Contact details:
 [veronika.koch@ufz.de](mailto:veronika.koch@ufz.de) (corresponding author,
 phone: +49 341 60253904, ORCID 0009-0007-7139-8887),
 [leonard.bolte@ufz.de](mailto:leonard.bolte@ufz.de) (ORCID
 0000-0002-6885-5641), [wiebke.harms@ufz.de](mailto:wiebke.harms@ufz.de)
 (ORCID 0009-0009-2390-7258),
 [klaus.henle@ufz.de](mailto:klaus.henle@ufz.de) (ORCID
 0000-0002-6647-5362),
 [annegret.grimm@ufz.de](mailto:annegret.grimm@ufz.de) (ORCID
 0000-0003-0577-7508) ## Data description – dog\_evaluation * This data was
 collected between 2021 and 2023 in Saxony, Saxony-Anhalt and Hesse
 (Germany) * We were granted a nature conservation exemption from the
 prohibitions under §44 para. 1 no. 1 and 2 of the Federal Nature
 Conservation Act (BNatSchG) and §4 para. 1 no. 1 of the Federal Species
 Protection Ordinance (BArtSchV) by the respective responsible lower nature
 conservation authorities (permit number: 364.620/65/15/1) for capturing
 and handling living natterjack toads (*Epidalea calamita*). ## Variable
 description – dog\_evaluation * Date – date of test * Time – time of test
 (NA: not available, was forgotten to note down) * Location – location of
 test * Transect – individual transect plot ID, plot IDs refer to transects
 within the open cast lignite mine (NA: not available, applies mostly to
 training and test data outside the lignite mine) * Dog - dog used in test:
 dog 1, 2, 3 or 4 (for more information see table 1 in the manuscript) *
 Handler – dog handler (Person A, Person B) * Assistant – Person helping
 and assisting, e.g. hiding target odour (NA: not available, either no
 assistant was present (not blind searches) or assistant was forgotten to
 note down) * InclDaysWorked – number of days the dog has been working
 prior to the day of the test * TrainingDay – indicates how many days of
 training the dog has had in total * TrialNumber – the consecutive
 numbering of the tests conducted. The numbering of the tests may differ
 from the total number of tests, as not all tests were included in the
 analysis (e.g. indoor trainings). * SessionDuration - the duration of the
 whole session with each session comprising between 1 and 15 tests and
 occasionally short training units * Temperature - temperature in °C
 measured with a TFA Dostmann thermometer. Temperature data of the
 fieldwork obtained from the meteorological station in Pegau, using daily
 average temperatures * Humidity - Humidity in % (NA: not available, either
 no hygrometer present or forgotten to write down) * Weather – weather
 during the test. Sunny: no clouds visible; partly cloudy: clouds visible
 but cover less than ¾ of the sky without rain; cloudy: clouds cover at
 least ¾ of the sky without rain; drizzle: drizzling rain; raining: more
 than drizzling rain; snowy rain: partly rain, partly snow * Wind – Wind
 condition during the test. Wind condition checked by scattering some baby
 powder and observing trees following Isyumov and Davenport (1975); none,
 slight, intermittent, moderate, or severe, referring to Beaufort scale
 0-1, 2, 3, 4, 5 or more, respectively * Terrain - predominant microhabitat
 type of the search area; grassland, high herbs: grassland with high grass
 / herbs above 20 cm height; grassland, low herbs: grassland with low grass
 / herbs up to 20 cm height; shrubland: almost no trees, many shrubs;
 forest, open understory: forest with up to ¼ of the search area covered
 with shrubs; forest, dense understory: forest with more than ¼ of the
 search area covered with shrub; plaines, sands and rocks: plaines with
 less than 50 % herbs and grasses, sandy ground and rocks; anthropogenic:
 any kind of anthropogenic habitat with concrete, no parks * Slope -
 inclination change and slope: level: no inclination (&lt;0.5°); slight:
 slight inclination throughout the search area (0.5-10°); medium:
 intermediate inclination throughout the search area (11-20°); steep: high
 inclination throughout the search area (&gt; 20°); mix: only some parts of
 the search area with inclination * Insect presence - quantity of flying
 insects present: none, few, or many, referring to no, single, or clouds of
 individuals, respectively * Leash – indicates whether the dog was without,
 on a short or long leash during the test * SearchArea - size of the area
 searched by the dog in m2 * Blindness – referring to the blindness of the
 test. Not blind: the handler and the assistant knew the position of the
 natterjack toad in the test; single blind: only the assistant but not the
 handler knew the position of the natterjack toad in the test; double
 blind: neither the assistant nor the handler knew the position of the
 natterjack toad in the test * Site - Surface on which the target odour
 (natterjack toad) was placed * Visibility - invisible: the placed
 individual toad was not visible to the handler and the dog upon alert;
 visible: the placed individual toad was visible to the handler and the dog
 upon alert * ToadCondition - alive: training or wild toad was alive; dead:
 training toad was dead * ToadAge - age categories based on size (adults
 &gt; 47 mm SVL, subadults 30 - 47 mm SVL, juveniles &lt; 30 mm SVL) *
 ToadSex – female, male or individual of unknown sex * FoundFirstAttempt –
 the toad was found by the dog at the first attempt, i.e. after covering
 the search area once * FoundSecondAttempt – the toad was found by the dog
 at the second attempt, i.e. after covering the search area twice (NA: not
 available as the dog found the target at first attempt) *
 FoundThirdAttempt – the toad was found by the dog at the third attempt,
 i.e. after covering the search area three times (NA: not available as the
 dog found the target at first or second attempt) * Alert – indicates
 whether the dog alerted independently or assisted, strong or light at the
 target odour (NA: not available, dog did not find the target i.e. no
 alert) * DogBehaviour - cooperative: dog obviously showed targeted
 searching with an upright posture and without panting during the search;
 distracted: dog did not clearly show targeted searching and also showed
 other behaviour (this could include listening to noises, observing
 people/dogs or obviously sniffing other traces such as those of other dogs
 or game); fatigued: dog showed targeted searching but without an upright
 posture and / or with panting during the search as well as a slower
 movement; unresponsive: dog would stop searching at all (Grimm-Seyfarth,
 2022) ## Data description – method\_comparison * This data was collected
 between 2021 and 2023 in Saxony and Saxony-Anhalt (Germany) * We were
 granted a nature conservation exemption from the prohibitions under §44
 para. 1 no. 1 and 2 of the Federal Nature Conservation Act (BNatSchG) and
 §4 para. 1 no. 1 of the Federal Species Protection Ordinance (BArtSchV) by
 the respective responsible lower nature conservation authorities (permit
 number: 364.620/65/15/1) for capturing and handling living natterjack
 toads (*Epidalea calamita*). ## Variable description – method\_comparison
 * date – date of the survey * year – year of the survey * survey_nr –
 number of the survey * method – method of the seurvey, ACB: artificial
 cover board, WDD: wildlife detection dog transect * habitat – habitat type
 of the survey, 1: open ground, low herb layer (mean = 17 cm), few plots
 with higher tree density, some shrubs as well as few hiding places, 2:
 open ground, higher herb layer (mean = 37 cm), some individual trees and
 shrubs as well as few hiding places, 3: little open ground, very rich in
 vegetation with high herb layer (mean = 38 cm), some hiding places * inds
 - number of individuals found * age – referring to size classes of toads
 (“juveniles” &lt; 30 mm snout-vent-length (SVL) and “adults” ≥ 30 mm SVL)
 * prec – precipitation on survey day in mm * prec_1, prec_2, prec_3,
 prec_4 - accumulated rainfall over one, two, three or four days prior to
 the survey * temp – temperature in °C, obtained from the meteorological
 station in Pegau, using daily average temperatures * number of
 plots/habitat/day - number of surveyed plots per habitat per day * success
 – success rate, calculated as number of individuals caught per method,
 habitat type and day divided by the number of plots surveyed in these
 categories and multiplied by 100