ON EARTH IS A MEGAPODE?
by Whit Gibbons
March 16, 2008
person interested in ecology should be pleased to see a recent announcement
in Species, the newsletter of the Species Survival Commission of IUCN,
the World Conservation Union. The Megapode Specialist Group formed in
1986 is "very keen to hear from young researchers who would like
to become involved in studying some of the most interesting birds on the
planet." Of course, the first question might be "What in the
world is a megapode?"
include birds called brush-turkeys, scrubfowl, incubator birds, and mound-builders.
Birds in this family bury their eggs in the soil, which may be warm volcanic
sands, sun-heated beaches, or mounds of earth with decaying leaf litter,
all of which generate heat that enhances incubation. Megapodes are noted
for the female's minimal effort at parental care once the eggs are laid.
The mother more or less walks away, leaving the eggs to hatch on their
own, like those of a turtle, snake, or lizard. The male stays in the vicinity
of the mound, attempting to regulate the temperature by adjusting the
amount of litter covering the eggs. When the young hatch, they are fully
mobile and are not fed by the parents. Letting offspring fend for themselves
is common for reptiles around the globe, but such parental indifference
is unusual among birds.
family consists of 22 species of generally brown, gray, or black birds
that resemble turkeys. Megapodes live in Indonesia, Australia, and islands
in the Indian Ocean and Polynesia, most being found in moist tropical
forests. Like turtles and alligators, the sex ratio of the clutch of at
least one species, the Australian brush-turkey, is determined by the temperature
of the nest during incubation, a rare phenomenon among birds.
In the mallee
fowl of Australia, which can weigh more than 30 pounds and is one of the
best known megapodes, the male constructs the nest. He digs a hole in
soft soil that can be three feet deep and more than 10 feet wide. He then
fills the hole and makes a large mound of twigs and other debris. During
the reproductive period of up to a month, the female typically lays one
egg a day on the mound, and the male buries it. The male stays with the
nest for weeks, adjusting the incubation temperature.
two dozen different species does not mean that megapodes are immune to
the many threats faced by modern wildlife. Eight species are considered
to be "at risk" according to the IUCN, the best internationally
known and most respected conservation organization. In practical terms,
"at risk" can be interpreted as "endangered." The
threats to megapodes include predation by natural predators, but megapodes
have evolved to deal with such natural setbacks. Unfortunately, habitat
destruction, a problem faced by wildlife worldwide, and harvesting of
the eggs by people exacerbate the situation. More than one-third of this
fascinating family of birds will soon be extinct unless conditions change.
specialist groups of the IUCN Species Survival Commission provide the
leadership for conservation efforts for specific plant and animal groups,
one of which is the megapodes. According to the IUCN, the biologically
informed and talented people who volunteer for these specialist groups
"contribute to technical and scientific counsel to biodiversity conservation
projects throughout the world." Their influence and impact is truly
global as they "provide advice to governments, international conventions,
and conservation organizations."
who wants to be truly engaged in global-scale conservation efforts, IUCN
is the organization to be involved with. The IUCN mission is "to
influence, encourage and assist societies throughout the world to conserve
the integrity and diversity of nature and to ensure that any use of natural
resources is equitable and ecologically sustainable." And they are
looking for new participants. If you are interested in unusual wildlife
and endangered species, and do not have family obligations, this might
be your opportunity to work with a bird that seems to have forsaken standard
out more about the IUCN Species Survival Commission and how you might
help with megapodes or another specialist group, go to www.iucn.org.
you have an environmental question or comment, email