Visual leopard identifications performed with camera traps using the capture–recapture method only consider areas of the skin that are visible to the equipment. The method presented here considered the spot or rosette formations of either the two flanks or the face, and the captured images were then compared and matched with available photographs. Leopards were classified as new individuals if no matches were found in the existing set of photos. It was previously assumed that an individual leopard’s spot or rosette pattern would not change. We established that the spot and rosette patterns change over time and that these changes are the result of injuries in certain cases. When compared to the original patterns, the number of spots may be lost or reduced, and some spots or patterns may change in terms of their prominence, shape, and size. We called these changes “obliterate changes” and “rejig changes”, respectively. The implementation of an earlier method resulted in a duplication of leopard counts, achieving an error rate of more than 15% in the population at Yala National Park. The same leopard could be misidentified and counted multiple times, causing overestimated populations. To address this issue, we created a new two-step methodology for identifying Sri Lankan leopards. The multi-point identification method requires the evaluation of at least 9–10 spot areas before a leopard can be identified. Moreover, the minimum leopard population at the YNP 1 comprises at least 77 leopards and has a density of 0.5461 leopards per km².

The study examines alloparental care and adoption in the Sri Lankan leopard population at Yala National Park, Sri Lanka. Using the multi‐point leopard identification method, it documents a remarkable instance: a leopard cub initially adopted by its maternal aunt and later by an unrelated female with no prior connection to the cub. The cub had a sibling litter mate, who was not seen in the park after the initial adoption ended by the maternal aunt. We consider this behavior noteworthy in especially solitary animal species such as leopards. Our study was conducted for a period of 2 years and 5 months (from February 2021 to July 2023). Our observations highlight the dynamics of these adoptions and the behaviors exhibited. Altruistic acts, such as feeding, brushing, and shielding the cubs, were observed. These inspections challenge the conventional knowledge regarding leopard behaviors. Notably, the adoption of the cub by unrelated females, despite the absence of genetic ties, exemplifies a form of mutually beneficial reciprocal altruism, offering advantages to both parties. The following study explains leopard adoptions using evolutionary theories like kin altruism and reciprocal altruism. It suggests factors such as genetic relatedness, mutual dependency, and possible misidentification influenced the act of adoption. These rare altruistic acts benefit the leopard population. Our study opposes traditional concepts of solitary Sri Lankan leopards. Altruistic behaviors, influenced by genetic relatedness and reciprocal benefits, emphasize social dynamics in predator populations. These findings enhance the understanding of evolutionary mechanisms and cooperative behaviors in maintaining population fitness in the Sri Lankan leopard population.

Introduction: The Sri Lankan leopard (Panthera pardus kotiya) is a sub species of the Panthera pardus family. It inhabits a variety of island’s habitats ranging from tropical rainforests to arid zone scrublands. This report documents the rare sighting of a newborn Sri Lankan leopard cub observed with its mother in a tree hole within Yala National Park, Sri Lanka. Results: On April 7, 2023, a female leopard and a newborn cub, estimated to be less than 10 days old, were sighted in a tree hole located approximately 15 feet above ground level. The mother leopard was observed nursing and grooming the cub, exhibiting relaxed yet vigilant behavior. The interaction was captured through high-resolution photography, capturing this rare display of maternal care and habitat use. Subsequent observations, including a follow-up sighting in 2024, indicated that the cub has continued to thrive, highlighting successful mother-cub bonding and survival. Discussion: This sighting marks the youngest leopard cub ever documented in the Yala National Park, Sri Lanka and highlights the suitability for leopard breeding within the ecosystem. These observations contribute to understanding critical aspects of leopard maternal care and habitat requirements, which impact the cub survival during early life. Continued conservation and research in Sri Lanka’s protected areas are essential to ensure the survival of this vulnerable species and its future within the island’s ecosystems.

Background: The study examines alloparental care and adoption in the Sri Lankan leopard population at Yala National Park, Sri Lanka. Using the Multi Point Leopard Identification Method, it documents a remarkable instance: a leopard cub [YM 67] initially adopted by its maternal aunt [YF 46], and later by another female [YF 15] with no prior connection to the cub. We consider this behaviour is noteworthy in especially solitary animal species such as leopards. Methods: Our study was conducted for a period of two years and five months (from February 2021 to July 2023). Our observations highlight the dynamics of these adoptions and the behaviours exhibited. Altruistic acts, such as feeding, brushing, and shielding the cubs, were observed. These inspections challenge the conventional knowledge regarding leopard behaviours. Notably, YF 15’s adoption of YM 67, despite their lack of genetic relatedness, exemplifies a form of mutually beneficial reciprocal altruism, benefiting both parties. Discussion: The following study explains leopard adoptions using evolutionary theories like kin altruism and reciprocal altruism. It suggests factors such as genetic relatedness, mutual dependency, and possible misidentification influenced the act of adoption. These rare altruistic acts benefit the leopard population. Conclusion: Our study opposes traditional concepts of solitary Sri Lankan leopards. Altruistic behaviours, influenced by genetic relatedness and reciprocal benefits, emphasize social dynamics in predator populations. These findings enhance the understanding of evolutionary mechanisms and cooperative behaviours in maintaining population fitness in the Sri Lankan leopard population.