2020-08-10

BLACK PANTHERS ? WHAT?

Sri Lankan black leopards are not a new species. Many people have that question, which is no wonder because after a long time now Sri Lankan scientists talking about Black Leopards.  Leopards are the top predators in the Island. The Sri Lankan leopard (Panthera pardus kotiya) is a subspecies endemic to the country.


When considering about the color variations of leopards, generally, background color of the pelage of Sri Lankan leopards is light yellowish brown to a slightly darker orange brown (tawny). Black spots are found on the head, neck, shoulders, and legs. On the sides and back, these spots form into broken circles or “rosettes”. An interesting point is that these rosettes only vary rarely have a black central spot.  According to the researchers, there is a direct relationship between the body color of the individuals with their environment and habitats. For example, leopards observed in the dry zone are smaller and lighter in color than those inhibiting upcountry habitats. Leopards in montane forests and wet zone forests have a brighter appearance. They are brighter than dry zone individuals to blend with dark green and dark light conditions. 


Very rarely some melanistic forms known as “Black Panthers” can occur. These melanistic individuals occur due to the mutation which is known as melanism. This name is weird because name is not exactly for the leopards. The term black panther is most frequently applied to black-coated leopards (Panthera pardus) of Africa and Asia and jaguars (P. onca) of Central and South America; black-furred variants of these species are also called black leopards and black jaguars, respectively. This name led people to get the wrong impression about these black leopards as different new species.


Melanism in the leopard is conferred by a recessive allele. Melanistic and non-melanistic animals can be littermates. According to the scientists, they thought that melanism confers a selective advantage under certain conditions since it is more common in regions of dense forest, where light levels are lower. Preliminary studies also suggest that melanism might be linked to beneficial mutations in the immune system. In these black leopards, the typical spotted markings are present but hidden due to the excess black pigments, which is called "ghost rosettes". Frequency of melanism appears to be approximately 11% over the leopard's range. Data on the distribution of leopard populations indicates that melanism occurs in five subspecies in the wild: including Sri Lankan leopard (P. p. kotiya). Based on records from camera traps, carcasses and snared individuals, melanistic leopards occur foremost in tropical and subtropical moist forests.


Apart from that, pseudo-melanistic leopards also can be occurred, these individuals have a normal background color, but the spots are more densely packed than normal and merge to obscure the golden-brown background color. Albinos also occur amongst leopards but none have been reported from Sri Lanka.


The black leopard has been a mystery for many years as sightings have been very rare due to the very low population and the solitary nature of the animals. Black panthers have been reliably reported from Hiniduma, Warakadeniya, Delwala, the Sinharaja forest and Guruthalawa. One of these animals was kept and displayed at the Dehiwala zoo in Colombo. Such melanistic animals can occur In the Dry zone, for example, one individual was shot in Thanamalwila and there is unconfirmed sighting from Dambulla area. 


Unfortunately, we lost already three black leopards during last decade by snares, typically set to trap deer or wild boar for bush meat. The two earlier recorded black leopards were also killed in snares, in 2009 and 2013, in southern Sri Lanka on the border of the Sinharaja Forest Reserve, a UNESCO World Heritage site. The Sri Lankan Black Leopard which was believed to be extinct had been captured on a trap camera in last October in the Central Hills. That was the first time that this type of leopard was captured on camera during research in Sri Lanka. Before that, the dead animals were displayed at the Giritale wildlife museum, as the final trace of the Sri Lankan Black Leopard.


Due to this tragic situation of snares, we lost more than six leopards during the first half of 2020. According to some researchers, 47 leopards were trapped in snares during the past decade. Of the total 79 leopard deaths reported during this period, 42 deaths were caused by snare-induced injuries. So this is not an easy thing to neglect. Therefore it is vital to take actions to mitigate these conflict situations to protect our endangered animals in Sri Lanka.



Chathuranga Dharmarathne

Senior Field Biologist

Felidae Carnivora Project

Sri Lanka

PC- from the internet