Know your islands
The West Indian Whistling Duck is the largest of the eight species of Whistling Duck to be found in the world.
It has numerous other common names, including Cuban Tree Duck, Black-billed Whistling Duck, Mangrove Duck, Night Duck, Yaguaza and Gingeon.
Its Latin name, Dendrocygna arborea, means tree-swan, and acknowledges the fact that many of these birds spend large parts of their time perched in trees.
With its long neck and legs, this duck is actually far more closely related to geese and swans, and like those birds, molt just once a year.
The following information was sourced from National Trust Information Sheets available at the Trust or online. Photograph by Frank Roulstone.
The West Indian Whistling Duck has a chestnut brown forehead, with a dark brown/black stripe from the crown down the back of the neck. Its face is pale ginger, fading to grey and white on the chin, throat and neck.
The feathers on the back and tail are medium brown, as are the wings. The primary feathers of the upper wing have silvery buff patches on them. The duck’s sides and flanks are black with distinctive white mottling.
They have black beaks and the legs and feet are dark blue/black. In flight, the duck’s legs trail behind them and are longer than the tail.
Normally a night feeder, the West Indian Whistling Duck spends daylight hours roosting in mangroves, woodlands or swamps. At dusk they fly to their feeding grounds which are usually ponds (fresh, brackish or salt water) surrounded by thick vegetation or seasonally flooded grasslands.
The ducks are largely vegetarian, feeding on fruits and seeds of grasses and other plants.
They also eat freshwater snails, however, and some even develop a taste for tadpoles!
The breeding season varies from island to island.
In Cayman it seems to occur at any time throughout the year, but most commonly at the onset of the rainy season in May/June.
Breeding pairs often stay together for more than one season, and both male and female build the nest. On Grand Cayman, the majority breed in the Central Mangrove Wetland, whereas on Little Cayman they breed throughout the wetlands.
Clutches typically number between five to 13 eggs and both birds take turns every 24 hours to incubate them. When the fledglings hatch, both parents assist in care for several weeks afterwards.
Today, the West Indian Whistling Duck is classed as a vulnerable species: its range is confined to the Cayman Islands, the Greater Antilles, and the Bahamas.
The duck’s natural predators are few, but introduced species such as rats, feral dogs and cats present a very real hazard to its survival.
The serious regional decline in its numbers in recent years is due principally to the rapid development of wetlands, the misuse of pesticides, and hunting.
Hunting of the West Indian Whistling Duck is now illegal in the Cayman Islands, but loss of wetland habitat, followed by poaching and hunting by dogs, remains the biggest single threat to this bird.
Grow Cayman Plants and encourage Cayman Wildlife! You can support native and migratory birds by keeping a natural yard. Plant a variety of native trees (Wild Fig attracts many species) and shrubs. They offer both food and protection for birds. Please control introduced animals – rats, cats and dogs! If you would like to get involved with the many activities in the National Trust’s Know Your Islands Program, please visit www.nationaltrust.org.ky, or call 949-0121.The weekly column from the National Trust is submitted by Marnie Laing, Education Programs Manager at the Trust.
Last week’s answer: In 1794, a great maritime tragedy took place known as “The Wreck of the Ten Sails.”
Trivia question: What fish generally lives in association with the pink-tipped anemone?
Look for the answer in next week’s feature!