Jacana

The jacana is a family of colorful and long-legged water birds hailing from the tropical wetlands around the world. There are eight documented species, plus several more extinct species known from the fossil record. Collectively, they are part of an order that includes waders and gulls. This article will cover some interesting facts about the identification, behavior, and diet of this unique bird.

Evolution

Fossil evidence of this family of waders, known for their unusual social organization and long digits, has been found in Africa and the Americas. The oldest, originating from Egypt in North Africa, dates back to the Oligocene (23 to 34 million years ago), while the specimen discovered in Florida dates back to the Pliocene (about 2.59 to 5.33 million years ago).

Types and Classification 

The Jacanidae family itself consists of six genera, with eight jacana species:

• African jacana (Actophilornis africanus): Notable for its bronze plumage, darkened wingtips, and bright blue beak, this avian is the bulkiest of all jacana species. Capable of weighing 9.1 oz on average, it can also measure up to 12 inches or slightly more in length.
• Bronze-winged jacana (Metopidius indicus): Found in Southeast Asia, this bird can be recognized by its dark bronze plumage with an emerald glimmer and a yellow-green beak. It is capable of growing to 11 inches in length, making it slightly smaller compared to the African Jacana.
• Comb-crested jacana (Irediparra gallinacea): The key distinguishing features of this bird consist of a fleshy pink wattle on the front portion of its head, a white face and throat, and dark dorsal feathers. The comb-crested jacana also has dark stripes that extend from its eyes, a short dark beak, and white tail feathers.
• Lesser jacana (Microparra capensis): Recognizable by its mottled plumage, the lesser jacana can be found in western, central, eastern, and southern Africa.
• Madagascar jacana (Actophilornis albinucha): Found in eastern Madagascar, this wader can be recognized by a head that is often black or mottled white and black at its upper half and black on its lower half, with dark bronze plumage.
• Northern jacana (Jacana spinosa): Found in Central America and the Caribbean, this species is distinguished by its black head and neck, as well as a rich russet upper body. Its yellow-tipped bill and pale green flight feathers also count among its key distinguishing features. The northern jacana is capable of growing to a length of 8 inches.
• Pheasant-tailed jacana (Hydrophasianus chirurgus): A white head, a slender white neck lined with a tuft of yellow feathers, and white wing feathers which stand out against dark brown plumage are this bird’s key distinguishing features. There’s also that tail too which extends in a slender arch of dark brown. Their range extends from the Middle East to East Asia, and they are the only members of their vast family to migrate, covering extensive distances.
• Wattled jacana (Jacana jacana): Located in the Caribbean and Latin America, this wader can be distinguished by its black and russet plumage and flight feathers, which are yellowish with a hint of green. It also has a yellow beak, which blends into a fleshy plate at the front of its head. Wattled jacanas are capable of growing to 10 inches or slightly longer.

Where to Find the Jacana

The jacana can be found in warm tropical locations all over the world, including Africa, southern Asia, Australia, Mexico and Central America, and South America. It also sometimes wanders as far north as the United States. They are specifically adapted to life in swamps, marshes, lagoons, and shallow lakes.

Nests

The female constructs a simple nest from the available plant material on floating islands.

Size, Appearance, and Behavior

The jacana is a medium-sized bird, measuring anywhere between six and 12 inches tall. The most prominent feature to aid with identification is the long, spindly legs (the feet, toes, and claws look a bit like twigs and branches). These birds come in all manner of different colors, including brown, cinnamon, white, and black, sometimes accompanied by yellow or green flight feathers. Females can measure up to twice the size of the males, but their plumage is otherwise almost identical, making identification somewhat difficult. Some species also have little red wattles or crowns near the beak.

The jacana is very well-adapted for the wetland ecosystem in which it lives. Their long legs and feet enable them to walk across lily pads and other floating vegetation without sinking. When threatened by a predator, they can stay underwater for long periods with the bill sticking above the surface to breathe properly. While they aren’t capable of long, sustained, powerful flights, they do glide gently for short distances over the surface of the water. The feathers also provide insulation to keep the bird warm and comfortable.

The jacana’s social system is notable for its complexity, particularly the polyandrous mating system in which females may have multiple male partners, and both sexes exhibit territorial behaviors. They complete much of their foraging and hunting alone, but they come together for breeding. These are also highly noisy birds that make a variety of different calls. Whether soothing a chick or spotting a predator, its verbal repertoire includes squeaks, whistles, cackles, coos, and twitters.

Diet

The jacana is an omnivore, although its diet mainly consists of insects, other invertebrates, and seeds, with occasional consumption of small fish.

What does the jacana eat?

The jacana feeds mostly on small insects. It supplements this with snails, worms, crabs, fish, mollusks, and seeds. They use their beaks, toes, and claws to turn over aquatic vegetation in search of food.

Predators, Threats, and Conservation Status

Seven of the eight species are classified by the IUCN Red List as of least concern. Only the Madagascar jacana is endangered. The greatest threat is the loss of its natural wetland habitat to agriculture and livestock. Wetlands are some of the most vulnerable ecosystems on the planet.

What eats the jacana?

This bird is preyed upon by otters, turtles, crocodiles, snakes, birds of prey, and large fish. As mentioned previously, these birds can run away or hide underwater upon sensing danger. The wattled jacana of the Americas also has sharp claws or spurs on the elbow wing to provide extra defense, and the bare, fleshy area on the front of the body may reflect light to provide camouflage.

Reproduction, Young, and Molting

One of the most fascinating facts about the jacana is that it has evolved a polyandrous breeding relationship in which the female keeps multiple mates at a time, rather than the opposite. Only the lesser jacana forms entirely monogamous breeding pairs. After mating, the female will produce a clutch of three or four eggs at a time. These glossy eggs have complex markings to help keep them safe and camouflaged among the vegetation. The father then assumes much of the responsibility of care, literally taking the eggs under his wing to keep them warm, while the female will often choose to mate again with another male to prepare the way for a new brood.

After an incubation period lasting anywhere between 22 and 28 days, the babies will emerge from the eggs, fluffy and striped. They will soon learn how to walk, swim, and dive within the first few hours after hatching. The babies will continue to stay with the father and learn how to forage for about 40 to 70 days. If the nest starts to sink under the water, then he will take them to a new site under his wings. The lifespan of this bird is currently unknown. However, about half of the chicks do not survive into adulthood.

What causes gender role reversal in jacana birds?

In an interesting reversal of the usual polygamous gender roles, the female jacana is the one who maintains a harem (an exclusive mating group) of up to four males at a time. All of the males who remain within her large territory (which can reach up to two football fields long) are considered to be part of her harem. The males provide most of the incubation and food, while the female defends the nest and the babies from threats. This allows the female to mate with as many males as possible in a short time. The jacana may have evolved this mating strategy to compensate for the extraordinary number of chicks lost to predators before adulthood.

Population

Population numbers are difficult to estimate and depend on the species. According to the IUCN Red List, there may be anywhere between 5 million and 50 million mature wattled jacanas in the wild. On the other hand, there may only be 800 to 1,600 mature Madagascar jacanas remaining.