Abstract
Monitoring wildlife population trends is essential for resource management and invasive species control, but monitoring data are hard to acquire. Citizen science projects may monitor species occurrence patterns in time and space in a cost-effective way. A systematic management program of exotic wild boar (Sus scrofa) and axis deer (Axis axis) in a protected area of northeastern Argentina (El Palmar National Park) provided a framework for implementing a wildlife monitoring system based on park-affiliated hunters. We assessed the level of agreement between three indices of relative abundance: hunter sightings and camera trapping for wild boar, axis deer, capybaras (Hydrochoerus hydrochaeris), brown brocket deer (Mazama guazoubira), and crab-eating and pampas foxes combined (Cerdocyon thous and (Lycalopex gymnocercus), and catch per unit effort (CPUE) for both exotic ungulates only. Most (74%) hunting parties participated in the monitoring program and contributed to its sustainability. Bland-Altman plots displayed large levels of agreement between methods across species, with larger systematic differences between sighting and camera-trapping indices for native species. Restricting camera-trapping to the same time window as hunter sightings substantially increased the agreement between methods across species. Sighting and CPUE indices revealed similar temporal trends and large variations in spatial patterns between species. Comparison of the number of sighted and killed exotic ungulates indicated that, on average, 17% of wild boar and 75% of axis deer escaped hunters. The three indices were appropriate metrics for management purposes and corroborated the sustained, high-level abundance of axis deer and low numbers of wild boar in recent years.
Data availability
The data that support the findings of this study are available from the corresponding author upon reasonable request.
Code availability
No custom codes were developed during the study. All image processing and analysis were conducted using pre-built tools. Please refer to the methods section for further details.
References
Allen ML, Roberts NM, Bauder JM (2020) Relationships of catch-per-unit-effort metrics with abundance vary depending on sampling method and population trajectory. PloS one 15(5):e0233444
Anderson DR (2003) Response to Engeman: index values rarely constitute reliable information. Wildl Soc Bull 31:288–291
August TA, Fox R, Roy DB, Pocock MJO (2020) Data-derived metrics describing the behaviour of field-based citizen scientists provide insights for project design and modelling bias. Sci Rep 10:1–12
Batista W, Rolhauser A, Biganzoli F, Burkart S, Goveto L, Maranta A, Pignataro A, Morandeira N, Rabadán M (2014) Las comunidades vegetales de la sabana del Parque Nacional El Palmar (Argentina). Darwiniana, Nueva Serie 2:5–38
Bland MJ, Altman DG (1986) Statistical methods for assessing agreement between two methods of clinical measurement. Lancet 327:307–310
Bland JM, Altman DG (1999) Measuring agreement in method comparison studies. Stat Methods Med Res 8:135–160
Blossey B (1999) Before, during and after: The need for long-term monitoring in invasive plant species management. Biol Invasions 1:301–311
Burton AC, Neilson E, Moreira D, Ladle A, Steenweg R, Fisher JT, Bayne E, Boutin S (2015) Wildlife camera trapping: A review and recommendations for linking surveys to ecological processes. J Appl Ecol 52:675–685
Cannon AR, Chamberlain DE, Toms MP, Hatchwell BJ, Gaston KJ (2005) Trends in the use of private gardens by wild birds in Great Britain 1995–2002. J Appl Ecol 42:659–671
Cattadori IM, Haydon DT, Thirgood SJ, Hudson PJ (2003) Are indirect measures of abundance a useful index of population density? The case of red grouse harvesting. Oikos 100:439–446
Chandler M, See L, Copas K et al (2017) Contribution of citizen science towards international biodiversity monitoring. Biol Conserv 213:280–294
Crall AW, Jarnevich CS, Young NE et al (2015) Citizen science contributes to our knowledge of invasive plant species distributions. Biol Invasions 17:2415–2427
Crespo JA (1982) Introducción a la ecología de los mamíferos del Parque Nacional El Palmar, Entre Ríos. Anales de Parques Nacionales (Argentina) 15:1–34
Cretois B, Linnell JDC, Grainger M, Nilsen EB, Rød JK (2020) Hunters as citizen scientists: contributions to biodiversity monitoring in Europe. Glob Ecol Conserv 23:e01077. https://doi.org/10.1016/j.gecco.2020.e01077
Cusack JJ, Dickman AJ, Rowcliffe JM, Carbone C, Macdonald DW, Coulson T (2015) Random versus game trail-based camera trap placement strategy for monitoring terrestrial mammal communities. PLoS One 10:1–14
Danielsen F, Burgess ND, Balmford A et al (2009) Local participation in natural resource monitoring: A characterization of approaches. Conserv Biol 23:31–42
Davis NE, Bennett A, Forsyth DM et al (2016) A systematic review of the impacts and man- agement of introduced deer (family Cervidae) in Australia. Wildl Res 43:515–532
De Mattos Vieira M, Von Muhlen E, Shepard G (2015) Participatory monitoring and management of subsistence hunting in the piagaçu-purus reserve, Brazil. Conserv Soc 13:254–264
DeCesare NJ, Newby JR, Boccadori VJ et al (2016) Calibrating minimum counts and catch-per-unit-effort as indices of moose population trend. Wildl Soc Bull 40:537–547
Delaney DG, Sperling CD, Adams CS, Leung B (2008) Marine invasive species: validation of citizen science and implications for national monitoring networks. Biol Invasions 10:117–128
Dobson ADM, Milner-Gulland EJ, Aebischer NJ et al (2020) Making messy data work for conservation. One Earth 2:455–465
El Bizri HR, Fa JE, Lemos LP, Campos-Silva JV, Vasconcelos Neto CF, Valsecchi J, Mayor P (2021) Involving local communities for effective citizen science: determining game species’ reproductive status to assess hunting effects in tropical forests. J Appl Ecol 58:224–235
Engeman RM (2005) Indexing principles and a widely applicable paradigm for indexing animal populations. Wildl Res 32:203–210
Evans C, Abrams E, Reitsma R, Roux K, Salmonsen L, Marra PP (2005) The neighborhood nestwatch program: Participant outcomes of a citizen-science ecological research project. Conserv Biol 19:589–594
Gilbert N, Clare JDJ, Stenglein JL, Zuckerberg B (2021) Abundance estimation methods for unmarked animals with camera traps. Conserv Biol. https://doi.org/10.1111/cobi.13517
Gürtler RE, Izquierdo VM, Gil G, Cavicchia M, Maranta A (2017) Coping with wild boar in a conservation area: impacts of a 10-year management control program in north-eastern Argentina. Biol Invasions 19:11–24
Gürtler RE, Rodríguez-Planes LI, Gil G, Izquierdo VM, Cavicchia M, Maranta A (2018) Differential long-term impacts of a management control program of axis deer and wild boar in a protected area of north-eastern Argentina. Biol Invasions 20:1431–1447
Harley SJ, Myers RA, Dunn A (2001) Is catch-per-unit-effort proportional to abundance? Can J Fish Aquat 58:1760–1772
Hess SC, Muise J, Schipper J (2015) Anatomy of an eradication effort. Removing Hawaii’s illegally introduced deer. Wildl Prof 9:26–29
Hofmeester TR, Rowcliffe JM, Jansen PA (2017) A simple method for estimating the effective detection distance of camera traps. Remote Sens Ecol Conserv 3:81–89
Hone J (2002) Feral pigs in Namadgi National Park, Australia: dynamics, impacts and management. Biol Conserv 105:231–242
Hope RM (2013) Rmisc: Ryan Miscellaneous. R package version 1.5. https://CRAN.R-project.org/package=Rmisc
Howe EJ, Buckland ST, Després-Einspenner ML, Kühl HS (2017) Distance sampling with camera traps. Methods Ecol Evol 8:1558–1565
Hulme PE (2006) Beyond control: wider implications for the management of biological invasions. J Appl Ecol 43:835–847
Jenks KE, Chanteap P, Damrongchainarong K, Cutter P, Cutter P, Redford T, Lynam AJ, Howard JG, Leimgruber P (2011) Using relative abundance indices from camera-trapping to test wildlife conservation hypotheses - an example from Khao Yai National Park, Thailand. Trop Conserv Sci 4:113–131
Jeschke JM (2008) Across islands and continents, mammals are more successful invaders than birds. Divers Distrib 14:913–916
Lancia RA, Bishir JW, Conner MC, Rosenberry CS (1996) Use of catch-effort to estimate population size. Wildl Soc Bull 24:731–737
Lizarralde M (2016) Especies exóticas invasoras (EEI) en Argentina: categorización de mamíferos invasores y alternativas de manejo. Mastozool Neotrop 23:267–277
Lowe S, Browne M, Boudjelas S, De Poorter M (2004) 100 of the world’s worst invasive alien species: a selection from the global invasive species database. Invasive Species Specialist Group, Auckland
Marrocoli S, Nielsen MR, Morgan D, van Loon T, Kulik L, Kühl H (2019) Using wildlife indicators to facilitate wildlife monitoring in hunter-self monitoring schemes. Ecol Indic 105:254–263
Mayor P, El Bizri HR, Bodmer RE, Bowler M (2017) Assessment of mammal reproduction for hunting sustainability through community-based sampling of species in the wild. Conserv Biol 31:912–923
McKinley DC, Miller-Rushing AJ, Ballard HL et al (2017) Citizen science can improve conservation science, natural resource management, and environmental protection. Biol Conserv 208:15–28
Meek PD, Ballard G, Claridge A et al (2014) Recommended guiding principles for reporting on camera trapping research. Biodivers Conserv 23:2321–2343
Merino ML, Carpinetti BN, Abba AM (2009) Invasive Mammals in the National Parks System of Argentina. Nat Areas J 29:42–49
Nichols JD, Williams BK (2006) Monitoring for conservation. Trends Ecol Evol 21:668–673
Noss A, Oetting I, Cuéllar RL (2005) Hunter Self-monitoring by the Isoseño-Guaraní in the Bolivian Chaco. Biodivers Conserv 14:2679–2693. https://doi.org/10.1007/s10531-005-8401-2
Pacifici K, Reich BJ, Miller DA, Pease BS (2019) Resolving misaligned spatial data with integrated species distribution models. Ecol 100:e02709
Palmer MS, Swanson A, Kosmala M, Arnold T, Packer C (2018) Evaluating relative abundance indices for terrestrial herbivores from large-scale camera trap surveys. Afr J Ecol 56:791–803
Parker RA, Weir CJ, Rubio N et al (2016) Application of mixed effects limits of agreement in the presence of multiple sources of variability: Exemplar from the comparison of several devices to measure respiratory rate in COPD patients. PLoS One 11:1–15
Pebesma E (2018) Simple features for R: standardized support for spatial vector data. The R Journal 10, 439-446. https://doi.org/10.32614/RJ-2018-009
QGIS.org (2021) QGIS Geographic Information System. QGIS Association. http://www.qgis.org/
R Core Team (2020) R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. https://www.R-project.org/
Rist J, Milner-Gulland EJ, Cowlishaw GU, Rowcliffe M (2010) Hunter reporting of catch per unit effort as a monitoring tool in a bushmeat-harvesting system. Conserv Biol 24:489–499
Rowcliffe JM, Field J, Turvey ST, Carbone C (2008) Estimating animal density using camera traps without the need for individual recognition. J Appl Ecol 45:1228–1236
Ruiz Selmo R, Minotti PG, Scopel A, Parimbelli M (2007) Análisis de la heterogeneidad fisonómico-funcional de la vegetación del Parque Nacional El Palmar y su relación con la invasión por leñosas exóticas. In ‘Teledetección–Hacia un mejor entendimiento de la dinámica global y regional’. Ed. Martin, Buenos Aires, pp 257-263
Schaller GB (1967) The deer and the tiger. University of Chicago Press, Chicago
Schaus J, Uzal A, Gentle LK et al (2020) Application of the Random Encounter Model in citizen science projects to monitor animal densities. Remote Sens Ecol Conserv 6:514–522
Simberloff D, Martin JL, Genovesi P et al (2013) Impacts of biological invasions: what’s what and the way forward. Trends Ecol Evol 28:58–66
Skalski JR, Ryding KE, Millspaugh JJ (2005) Analysis of Population Indices. In: Wildlife Demography, 1st edn. Elsevier, pp 359–433
Sullivan BL, Wood CL, Iliff MJ, Bonney RE, Fink D, Kelling S (2009) eBird: A citizen-based bird observation network in the biological sciences. Biol Conserv 142:2282–2292
Swanson A, Kosmala M, Lintott C, Simpson R, Smith A, Packer C (2015) Snapshot Serengeti, high-frequency annotated camera trap images of 40 mammalian species in an African savanna. Sci Data 2:1–14
Tennekes M (2018) tmap: Thematic Maps in R. J of Statistical Softw 84:1-39. https://doi.org/10.18637/jss.v084.i06
Toms MP, Newson SE (2006) Volunteer surveys as a means of inferring trends in garden mammal populations. Mammal Rev 36:309–317
Walters C (2003) Folly and fantasy in the analysis of spatial catch rate data. Can J Fish Aquat Sci 60:1433–1436
Warton DI, Blanchet FG, O’Hara RB, Ovaskainen O, Taskinen S, Walker SC, Hui FK (2015) So many variables: joint modeling in community ecology. Trends Ecol Evol 30:766–779
Wickham H (2016) ggplot2: Elegant Graphics for Data Analysis. Springer-Verlag, New York
Wickham et al (2019) Welcome to the tidyverse. J of Open Source Softw 4(43), 1686. https://doi.org/10.21105/joss.01686
Acknowledgments
We acknowledge with thanks the valuable assistance of park rangers: R. Achilli, C. Croci, A. Delaloye, L. Loyza, E. Munich, C. Sosa, J. Yone, and J. Zermathen; members of the UBA-sponsored volunteer program: M. Bongianino, V. Lopez Emprin, A. de Miguel, M. Burgueño, S. Spilzbarg. W. Cabascango, T. Chomarat, B. Galharret, L. Rosin, and L. Santoni; and members of the Hunting Club for Conservation “Tierra de Palmares”: C. Bonato, D. Chervo, J. Fabre, C. Gómez, Celso and Ceferino Jacquet, H. and S. Larrachao, M. Morend, E. Portillo, and A. Tisoco.
Funding
Field activities were supported by the volunteer university students’ program of the Federal Ministry of Education (2016) and UBANEX (2017). The participation of REG was supported by University of Buenos Aires (UBACYT 20020170100779BA) and Agencia Nacional de Promoción Científica y Técnica of Argentina (PICT-2015-2921). The funders had no role in study design, data collection and analysis, decision to publish and preparation of the manuscript.
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GN, LIRP and REG designed the study, GN, LIRP, AM and AAM acquired the data, GN, LIRP and REG analyzed the data, GN, LIRP and REG drafted the document, GN, LIRP, AM, AAM and REG edited the document.
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All applicable international, national, and/or institutional guidelines for the care and use of animals were followed. All procedures performed in studies involving animals were in accordance with the ethical standards of the institution or practice at which the studies were conducted.
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Nicosia, G., Rodríguez-Planes, L.I., Maranta, A.A. et al. Combining citizen science and recreational hunters to monitor exotic ungulates and native wildlife in a protected area of northeastern Argentina. Biol Invasions 23, 3687–3702 (2021). https://doi.org/10.1007/s10530-021-02606-4
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DOI: https://doi.org/10.1007/s10530-021-02606-4