Therya_notes_142

THERYA NOTES 2024, Vol. 5 : 16-19 DOI: 10.12933/therya_notes-24-142 ISSN 2954-3614

New record of the Neotropical otter (Lontra longicaudis) in the forests of the Río Sapo basin, El Salvador

Nuevo registro de la nutria neotropical (Lontra longicaudis) en los bosques de la cuenca de Río Sapo, El Salvador

Xochilt Pocasangre-Orellana1*, and Francisco S. Álvarez1

1Fundación Naturaleza El Salvador, Departamento de Investigación. Calle Francisco Campos 166, Colonia Escalón, C. P. 01101. San Salvador, El Salvador. E-mail: xochpoca@gmail.com (XP-O); samuel_biologo@hotmail.com (FSA).

*Corresponding author

The Neotropical otter Lontra longicaudis is an understudied species in El Salvador and our knowledge about it is scarce. The aim of this contribution was to record the occasional presence of L. longicaudis in the Río Sapo basin, El Salvador. The fieldwork was carried out between August and September 2022 using 20 camera traps in the Río Sapo basin. We recorded the first photographs and video of 2 individuals of L. longicaudis within the forest in the Río Sapo basin. We confirmed the occurrence of L. longicaudis in the Río Sapo basin using the forest, showing the importance of considering adjacent forests of body waters for the study and monitoring of this species.

Key words: Biological corridor; camera traps; citizen science; conservation; endangered species.

La nutria neotropical Lontra longicaudis es una especie poco estudiada en El Salvador y nuestro conocimiento sobre la especie es escaso. El objetivo de esta investigación fue registrar la presencia ocasional de L. longicaudis en la cuenca de Río Sapo, El Salvador. El trabajo de campo se llevó a cabo entre agosto y septiembre de 2022 usando 20 cámaras trampa en la cuenca de Río Sapo. Reportamos las primeras fotografías y video de 2 individuos de L. longicaudis dentro del bosque en la cuenca de Río Sapo. Confirmamos la ocurrencia de L. longicaudis en la cuenca de Río Sapo utilizando el bosque, mostrando la importancia de considerar bosques adyacentes a cuerpos de agua para el estudio y monitoreo de esta especie.

Palabras clave: Cámaras trampa; ciencia ciudadana; conservación; corredor biológico; especie en peligro.

El Salvador is one of the countries with less forest cover in América and has been severely deforested in the last decades (Carr et al. 2006; Dull 2008), and now, most of their cover is a secondary forest in private land and coffee plantations (Blackman et al. 2012; MARN 2018). In our study area, at the northern Morazán department, many forests were resurged by natural succession on abandoned agricultural and ranching lands during 12 Civil War years (Hecht et al. 2006; Hecht and Saatchi 2007; Valencia et al. 2011; Redo et al. 2012) and now have connected secondary forest (degraded forest) under no protection status where many endangered species live such as Neotropical otter (Lontra longicaudis) and other wildlife species (Morales-Rivas et al. 2020; Rivera et al. 2020). However, these forests are undergoing deforestation due to the rapid development of tourism projects and new human settlements due to the return of owners claiming their lands after the war.

In El Salvador, due to the loss and fragmentation of the landscape, L. longicaudis is classified as endangered (MARN 2015). Also, it is considered a Near Threatened species by the International Union for Conservation of Nature, IUCN (Rheingantz et al. 2021). Despite this species being considered has priority of conservation in El Salvador, L. longicaudis has been little studied, a widespread problem for this species in many countries within its distribution (de Almeida and Pereira 2017). However, to our knowledge, there are only 3 scientific papers published with 14 L. longicaudis records in El Salvador (Owen and Girón 2012; Funes and Pocasangre-Orellana 2020; Rivera et al. 2020) and 1 unpublished record in the online portal of Global Biodiversity Information Facility (GBIF; http://www.gbif.org). This shows gaps in information that make it difficult to understand the basic aspects of the ecology of L. longicaudis and make it difficult to make decisions for the conservation of this species. Therefore, herein we contributed to the knowledge of L. longicaudis in El Salvador and reported the first Neotropical otter record using camera traps in the Río Sapo basin. Also, we make notes on habitat use and make recommendations for the study and protection of the species.

The fieldwork was carried out in the Río Sapo basin, municipality of Arambala, near the town of Arambala (13° 55' 13.34" N; 88° 8' 1.01" W), department of Morazán, El Salvador. The area has a well-defined dry season from November to April and a rainy season from May to October. The biophysical characteristics of the Central American Dry Corridor influence the area. Therefore, it is susceptible to drastic changes such as low precipitations or prolonged periods of drought (Quesada-Hernández et al. 2019). The study area has secondary forests that have resulted from a natural forest recovery process on abandoned agricultural and livestock lands. The predominant vegetation is pine-oak forest and deciduous forest. The fieldwork was part of an exploratory study on mammal activity in the study area and as part of local community people training for biodiversity monitoring in the Río Sapo forests under a citizen science approach. Also, 5 unstructured interviews of local people were carried out to identify wildlife activity in the area. The fieldwork was carried out between August and September 2022. Twenty camera traps were placed within the forest at a minimum distance of 300 m between each camera. The records were added to the database of the National Mammal Collection of the Institute of Biology of Universidad Nacional Autónoma de México (UNAM 2023).

Herein, 3 photographs and 1 video of L. longicaudis were recorded for the first time using camera traps in the Río Sapo basin with catalog number of the video IBUNAM-CFB-78952. The records were taken in the forest (Figure 1), not near the banks of the rivers, streams, or burrows, sites where usually put camera traps in specific otter studies. Two individuals of L. longicaudis of unknown sex were recorded on August 18, 2022, during daylight hours (15:19 hr) at 13° 56' 3.36" N and 88° 6' 22.19" W at an elevation of 720 m. The individuals were recorded moving within the forest at 740 m from the main river, 325 m from a seasonal stream, and 115 m from another small seasonal stream. The individuals did not leave traces of excrement or food scraps. Probably, this record corresponds to 1 female and her cub, evidencing parental care and reproductive activity in the Río Sapo basin. We identified L. longicaudis by the morphological characteristics of the body of a semi-aquatic mammal such as an elongated body, uniformly dark brown fur above and slightly lighter below, long pointed tail, and short ears (Kruuk 2006).

This is the first photographed record of L. longicaudis using the forest within the Río Sapo basin. According to local people, this species has been seen occasionally crossing the forest between rivers. Previous studies in El Salvador about this species only recorded feces, sightings, and photographs in main rivers and streams, but not in the forest (Funes and Pocasangre-Orellana 2020). It is well known that L. longicaudis can use riparian zones for scent marking, holt areas, grooming, or foraging activities (Kruuk 2006; Rheingantz et al. 2017). However, the interactions of this species inside the forest, outside the water, or outside of riverbanks are little understood. Therefore, it is imperative to know the interaction of this species with the forests to formulate better conservation strategies.

Lontra longicaudis distribution has been restricted to a few rivers in El Salvador (Funes and Pocasangre-Orellana 2020). Our record confirms the activity of the species in the Río Sapo basin within the upper Lempa River basin (transboundary basin) near the borders with Honduras (Figure 2), therefore this record can be relevant for the southeastern region of Honduras, a region where not have records yet. Factors such as seasonality probably contribute to the movement patterns of L. longicaudis in our study area (Arellano Nicolás et al. 2012; Santiago-Plata et al. 2013; Cianfrani et al. 2018). Probably during the rainfall season, the otter moves through the forest between rivers and small streams to search for food or shelter or such as activities for parental care. However, more studies will be necessary to determine the factors that affect the movement patterns of this species in the basin. On the other hand, many rivers and streams dry up during the dry season in our study area, then the main river is often used for water extraction and tourism, which is a potential threat to the availability of habitat for the species during the dry season. Also, our study area is located within the Central American Dry Corridor, therefore it is susceptible to drastic changes in precipitation and temperature (Quesada-Hernández et al. 2019). Additionally, climatic phenomena such as ENSO (El Niño–Southern Oscillation) and climate change can influence the habitat availability of the species by reducing river flow due to prolonged periods of drought, decreased precipitation, and increased temperature (Cianfrani et al. 2018). Therefore, it is probable that the species can use forests as a temporary refuge or feeding site during these less favorable conditions.

Therefore, the conservation of adjacent forests and their connectivity will be a key strategy for the conservation of L. longicaudis in El Salvador, specifically in the Río Sapo basin, and will be necessary to create strategies that encourage forest owners to protect these lands and avoid deforestation. Due to the small percentage of Salvadorean protected areas (UNEP-WCMC 2023), conservation strategies based strictly on protected areas will not guarantee the conservation of species such as the Neotropical otter, where the most of records do not occur in protected areas (Funes and Pocasangre-Orellana 2020). Therefore, will be necessary to create conservation strategies that include not only the protection of riparian forests but also the expansion of these areas that allow the establishment of biological corridors (Crespin and García-Villalta 2014) that connect basins and conserve areas that have critical ecological requirements for developing and conserving L. longicaudis (Latorre-Cardenas et al. 2021).

Acknowledgements

We thank Fundación Naturaleza El Salvador for providing camera traps for this research project. Also, we are grateful to S. Amaya, E. Chica, and A. Ramírez for their support in the fieldwork, and we are grateful to private landowners who allowed us to carry out this study on their properties, and 2 anonymous reviewers for their comments that helped improve the first version of the note.

Literature cited

Arellano Nicolás, E., E. Sánchez núñez, and M. A. Mosqueda Cabrera. 2012. Distribución y abundancia de la nutria neotropical (Lontra longicaudis) en Tlacotalpán, Veracruz, México. Acta Zoológica Mexicana (nueva serie) 28:270-279.

Blackman, A., B. Ávalos-Sartorio, and J. Chow. 2012. Land cover change in agroforestry: Shade coffee in El Salvador. Land Economics 88:75-101.

Carr, D., et al. 2006. Agricultural change and limits to deforestation in Central America. Pp. 91-107 in Agriculture and Climate Beyond 2015: A New Perspective on Future Land Use Patterns. Environment & policy vol. 46. Springer. Dordrecht, The Netherlands.

Cianfrani, C., et al. 2018. More than range exposure: Global otter vulnerability to climate change. Biological Conservation 221:103-113.

Crespin, S. J., and J. E. García-Villalta. 2014. Integration of land-sharing and land-sparing conservation strategies through regional networking: the Mesoamerican Biological Corridor as a lifeline for carnivores in El Salvador. Ambio 43:820-824.

de Almeida, L. R., and M. J. R. Pereira. 2017. Ecology and biogeography of the Neotropical otter Lontra longicaudis: existing knowledge and open questions. Mammal Research 62:313-321.

Dull, R. A. 2008. Unpacking El Salvador’s ecological predicament: Theoretical templates and “long-view” ecologies. Global Environmental Change 18:319-329.

Funes, G., and X. Pocasangre-Orellana. 2020. New records of Lontra longicaudis (Olfers, 1818) (Carnivora, Mustelidae) in El Salvador. Check List 16:1329-1335.

GBIF.org. 2023. GBIF Occurrence Download. https://doi.org/10.15468/dl.dxdy8n. Accessed on October 14, 2023.

Hecht, S. B., et al. 2006. Globalization, forest resurgence, and environmental politics in El Salvador. World Development 34:308-323.

Hecht, S. B., and S. S. Saatchi. 2007. Globalization and forest resurgence: changes in forest cover in El Salvador. Bioscience 57:663-672.

Kruuk, H. 2006. Otters: ecology, behaviour and conservation. Oxford University Press. New York, U.S.A.

Latorre-Cardenas, M. C., et al. 2021. Do landscape and riverscape shape genetic patterns of the Neotropical otter, Lontra longicaudis, in eastern Mexico? Landscape Ecology 36:69-87.

Ministerio de Medio Ambiente y Recursos Naturales (MARN). 2015. Listado oficial de vida silvestre amenazada o en peligro de extinción. El Salvador. https://www.ambiente.gob.sv. Accessed on June 25, 2023.

Ministerio de Medio Ambiente y Recursos Naturales (MARN). 2018. Inventario Nacional de Bosques de El Salvador. El Salvador. https://www.ambiente.gob.sv. Accessed on June 20, 2023.

Morales-Rivas, A., et al. 2020. Big cats are still walking in El Salvador: first photographic records of Puma concolor (Linnaeus, 1771) and an overview of historical records in the country. Check List 16:563-570.

Owen, J. G., and L. Girón. 2012. Revised checklist and distributions of land mammals of El Salvador. Occasional Papers, Museum of Texas Tech University 310:1-32.

Quesada-Hernández, L. E., et al. 2019. Dynamical delimitation of the Central American Dry Corridor (CADC) using drought indices and aridity values. Progress in Physical Geography 43:627-642.

Redo, D. J., et al. 2012. Asymmetric forest transition driven by the interaction of socioeconomic development and environmental heterogeneity in Central America. Proceedings of the National Academy of Sciences 109:8839-8844.

Rheingantz, M. L., V. M. Santiago‐Plata, and C. S. Trinca. 2017. The Neotropical otter Lontra longicaudis: a comprehensive update on the current knowledge and conservation status of this semiaquatic carnivore. Mammal Review 47:291-305.

Rheingantz, M., et al. 2021. Lontra longicaudis. The IUCN Red List of Threatened Species 2021:e.T12304A164577708.

Rivera, J. G. A., et al. 2020. A community-based survey of mammals in the Río Sapo basin, El Salvador. UNED Research Journal 12:e3015-e3015.

Santiago-Plata, V. M., et al. 2013. Aspectos ecológicos de la nutria neotropical (Lontra longicaudis annectens) en el camino La Veleta en la Laguna de Términos, Campeche, México. Therya 4:265-280.

Universidad Nacional Autónoma de México (UNAM). 2023. IBdata: Base de Datos de las Colecciones Biológicas del Instituto de Biología, UNAM (en línea), Instituto de Biología, Universidad Nacional Autónoma de México. México. Colección de Fotocolectas Biológicas; número de catálogo: IBUNAM-CFB-78952.

UN Environment World Conservation Monitoring Centre (UNEP-WCMC). 2023. Protected Area Profile for El Salvador from the World Database on Protected Areas, November 2023. Available at: www.protectedplanet.net. Accessed on June 5, 2023.

Valencia, D. H., et al. 2011. Tropical forest recovery and socio-economic change in El Salvador: An opportunity for the introduction of new approaches to biodiversity protection. Applied Geography 31:259-268.

Associated editor: Jesus R. Hernández Montero.

Submitted: July 11, 2023; Reviewed: December 11, 2023.

Accepted: January 23, 2024; Published on line: February 12, 2024.