JaguaRS
- Tracking and monitoring jaguars in Costa Rica over time and space
- Identifying and documenting each individual detected
- Gathering and analyzing precious data for jaguar conservation
America’s largest wildcat
The jaguar (Panthera onca) is America’s largest wildcat, but due to its elusive behavior, it remains one of the least known. This powerful cat spends most of its time hidden in the heart of the tropical rainforest. Active during both day and night, it uses its spotted fur as camouflage, and its ability to swim and climb to stalk its target without being detected. With the most powerful jaw of all carnivores, it has a unique hunting technique: piercing its prey’s skull and killing it instantly.
As an APEX predator, it sits at the top of the food chain, playing the role of regulator by preventing the proliferation of its prey and thus maintaining the balance of the ecosystem. Furthermore, it is an 'umbrella species,' which means that its needs encompass those of many other species.
Since its development requires a perfectly healthy environment, protecting the jaguar means protecting the entire ecosystem of which it is part.
Jaguars POPULATIONS
Threats
Costa Rica, once widely populated by jaguars, was considered one of the best places to observe them. But the privilege of sighting a jaguar first-hand has become extremely rare. Today, only a fraction of the population remains, detected by wildlife monitoring camera traps and identified by their unique patterns.
Since colonization and especially during the years 1960-1970 (when an estimated 18,000 were killed yearly for skin trade), jaguars have lost over 46% of their original territory and their numbers have decreased by half, threatening the species, mainly in Central America. Depending on the period and the region, the reasons for that decline differ:
Poaching
- Skin, canines and organs trade
- Resale to collectors
- Livestock protection
- Sport hunting
- Poaching of their prey
Deforestation
- Agriculture
- Cattle farming
- Urbanization
- Rare woods illegal trade
genetic
impairment
- Geographic isolation
- Decreasing population
- Inbreeding
Nonetheless, this situation is not irreversible. Slowly, awareness is growing and most of the Costa Rican South Pacific is still covered by pristine rainforest. It is therefore one of the last natural spaces that jaguars could win back, a key zone that would greatly favor the survival of the species in Central America. The preservation of the last jaguars of the Osa Peninsula is a major argument justifying the need to create biological corridors between already protected areas, becoming a model of interconnected conservation.
BLACK JAGUARS
Rarer than the yellow-coated individuals, black jaguars (or melanistic jaguars) are estimated to represent less than 6% of the total jaguar population. Throughout their range, these mysterious felines have fueled various legends and rumors since ancient times.
What is melanism?
Melanism refers to a condition in which an individual is darker than others of its species. This phenomenon results in a black or dark coloration and is caused by a genetic mutation that leads to abnormally high production of melanin in the skin and fur. They still display spots, also known as rosettes, which are visible depending on the light, although they may be less pronounced than on their yellow-coated counterparts.
Why do some individuals exhibit melanism?
One hypothesis is that this genetic characteristic is more common in individuals inhabiting higher altitudes, such as the Talamanca Mountain Range in Costa Rica, where the climate is much colder than in lowland forests. Their black coloration would allow them to absorb more light and retain more heat. It would also enable the black jaguar to better camouflage itself in the darkness of these dense forests, often shrouded in mist, providing them with an advantage for hunting. Therefore, the environment is believed to be a key factor in the occurrence of melanism in jaguars.
A matter of genetics
For each of its characteristics, every living being has two genes inherited from each parent, and only one of the two is expressed. In jaguars, the melanistic gene is dominant, which means it prevails over the recessive yellow color gene. Regardless of their color, if two jaguars each carry the yellow color gene and the black color gene, their offspring would have a 3 in 4 chance of being black and a 1 in 4 chance of being yellow. To simplify, two black jaguars could potentially give birth to a yellow offspring, whereas two yellow jaguars could not give birth to a black one.
Myths
Contrary to popular belief, the melanistic jaguar often referred as the black panther is not a separate species. Two species that exhibit melanism are commonly referred to as black panthers: the jaguar (found exclusively in the Americas) and the leopard (found in Africa and Asia).
It is also said that black jaguars are larger and more aggressive than the yellow individuals. However, these assumptions are not based on any scientific evidence and are more related to popular belief.
Prey
Jaguars are APEX predators with a diverse diet, preying on over 85 different species. They are known for their incredible strength and hunting abilities, often targeting large prey such as peccaries, tapirs and sea turtles. Their powerful jaws allow them to pierce through the skulls of their prey, enabling them to hunt unexpected animals like caimans and boas. In addition, jaguars also consume smaller animals such as monkeys, birds, and fish.
This varied diet highlights their adaptability and crucial role in maintaining the ecological balance of their habitats, making their conservation essential for the health of the ecosystems they inhabit. Jaguars' hunting success rates, which vary based on region and prey availability, are generally high compared to other big cats, typically ranging from 50-60%.
Nonetheless, some of these prey, such as the white-lipped peccary (Tayassu pecari) and the Baird’s tapir (Tapirus bairdii), are endangered due to poaching. Their decline puts the survival of jaguars at risk.
Reproduction
Jaguars typically reach sexual maturity around two to three years of age. The mating season can occur year-round, although there may be regional variations. Female jaguars signal their readiness to mate through vocalizations and scent markings.
After a gestation period of approximately 93-105 days, a litter of one to three cubs is born in a secluded den. The cubs are born blind and helpless, relying entirely on their mother for warmth, protection, and nourishment. They begin to explore their surroundings at around two weeks old and are weaned by six months.
However, they stay with their mother for up to two years, learning essential hunting and survival skills before venturing out on their own. The extended period of maternal care ensures that jaguar cubs are well-prepared to thrive in their natural habitats.
Jaguar cub mortality rates are high, with about 40-50% not surviving to adulthood. Primary causes include predation by other large carnivores such as pumas or other male jaguars, and natural hazards like flooding or falling from trees.
Detecting jaguars vocalizing, mating or with cubs are extremely rare events making these footages captured by Las Oncas’ camera traps, highly valuable.
OUR JAGS
Want to make a difference in jaguar conservation? Adopt a jaguar today!
Negro
El Dorado
Male 15
Lupo
Panatico
Female 7
Female 6
El Renco
Batman
Encanto
Leonidas
Tala
Female 5
Don Jag
Nubosa
Lwazo
Evander
Lada
Pinto
Gallo
Shāhdosa
Tico
La Quinta
Rüka
Scientific contributions
