Dynamic occupancy modelling of Asian elephants (Elephas maximus) reveals increasing landscape use in Nepal.

Large mammals with general habitat needs can persist throughout mixed used landscapes, however, human-wildlife conflict frequently leads to their restriction to protected areas. Conservation efforts, especially for reducing conflicts with humans, can enhance tolerance of humans towards species like Asian elephants (Elephas maximus) in human-dominated landscapes. Here, we examine how elephant use in the Chure Terai Madhesh Landscape (CTML) covering the entire elephant range of Nepal changed between 2012 and 2020 in relationship to protection status and environmental conditions. We systematically surveyed ~ 42,000 km2 of potential habitat, by dividing the study area into 159 grid cells of 15 × 15 km2 and recorded elephant signs during the cool, dry season in three years (2012, 2018 and 2020). We analyzed the survey data in a single-species, multi-season (dynamic) occupancy modeling framework to test hypotheses regarding the influence of environmental conditions and protected area status on landscape use by elephants over time. The best-supported model included protected area effects on initial use, colonization, and detection probability as well as temporal variation in colonization and detection probability. Initial use and colonization rates were higher in protected areas, however elephants increasingly used cells located both inside and outside the protected areas, and the difference in use between protected areas and outside declined as elephants use became prevalent across most of the landscape. While elephant use was patchily distributed in the first year of surveys consistent with past descriptions of four sub-populations, elephant use consolidated into a western and eastern region in subsequent years with a gap in their distribution occurring between Chitwan and Bardiya National Parks. Our manuscript highlights the increasing landscape use by elephants in both protected areas and areas outside protected areas and suggests that management interventions that focus on reducing conflicts can promote greater use of both protected areas and areas outside of protected areas.

Unusual cystic hygromas: Case report.

INTRODUCTION AND IMPORTANCE: Cystic hygromas are congenital lymphangiomas that arise from a developmental anomaly in the lymphatic system. Typically detected in early childhood, their incidence in adolescents and at the chest wall or axillary area is rare. CASE PRESENTATION: We report two cases, a 14-year-old male child (Case I) and a 1-year-old male infant (Case II), who presented with swelling in unusual locations, the right axillary region and the right anterolateral chest wall respectively. Local examination findings were indicative of a cystic hygroma in the first case, while in the second case, characteristic transillumination was not seen due to a complication: hemorrhage within the cyst. The diagnoses were established after a correlation of the patient's history, and clinical findings with radiological investigations. Both underwent surgical intervention and had no complications. Histopathology of the post-operative specimens confirmed the diagnoses. DISCUSSION: The diagnosis of cystic hygroma is made in the totality of thorough history taking, clinical examination, and radiological and histopathological investigations. Though most cases typically manifest before the age of two years and in the cervicofacial area, unusual locations and delayed presentation can occur. Surgical excision is a safe and effective treatment modality for these lesions. CONCLUSION: Although a rare entity, cystic hygroma should be considered a possible differential diagnosis of any swelling in the pediatric population.

Tracking forest loss and fragmentation between 1930 and 2020 in Asian elephant (Elephas maximus) range in Nepal.

Forest cover is the primary determinant of elephant distribution, thus, understanding forest loss and fragmentation is crucial for elephant conservation. We assessed deforestation and patterns of forest fragmentation between 1930 and 2020 in Chure Terai Madhesh Lanscape (CTML) which covers the entire elephant range in Nepal. Forest cover maps and fragmentation matrices were generated using multi-source data (Topographic maps and Landsat satellite images of 1930, 1975, 2000, and 2020) and spatiotemporal change was quantified. At present, 19,069 km2 forest cover in CTML is available as the elephant habitat in Nepal. Overall, 21.5% of elephant habitat was lost between 1930 and 2020, with a larger (12.3%) forest cover loss between 1930 and 1975. Area of the large forests (Core 3) has decreased by 43.08% whereas smaller patches (Core 2, Core 1, edge and patch forests) has increased multifold between 1930 and 2020. The continued habitat loss and fragmentation probably fragmented elephant populations during the last century and made them insular with long-term ramifications for elephant conservation and human-elephant conflict. Given the substantial loss in forest cover and high levels of fragmentation, improving the resilience of elephant populations in Nepal would urgently require habitat and corridor restoration to enable the movement of elephants.