Daintree Cassowaries

Cassowary

Frequently Asked Questions

1.How large can a Cassowary grow?
A great difference exists between the adult male and female cassowary. The larger female can stand a little over 2 metres and weigh in at over 80 kgs.
2.How do you tell the difference between a male and female Cassowary?
Visually the differences are subtle. Generally the female appears to be a more substantial bird compared to the male. When you see a bird on its own this can be quite a subjective exercise. If you are fortunate enough to be able to measure a cassowary footprint the size can be a good indicator of its sex. The female’s foot is longer than 210 mm while the male has a foot smaller than 210 mm.
3.Are Cassowaries found anywhere else?
New Guinea and some of its surrounding islands play host to 3 species of cassowaries one of which (Southern Cassowary) extends into Northern Queensland.
4.What is the casque for?
Much speculation exists regarding the purpose of the casque. Some biologists have suggested that it aids the bird when moving through the forest (a form of protective helmet), some believe that it is indicative of dominance among other birds (it grows with age) and still others suggest that it enables a cassowary to hear, at great distances, the booming calls of potential mates and rivals. This latter suggestion has gained credence because of the structure of the casque and its proximity to the hearing canal.
5.When is the breeding season?
Like all bird species cassowary breeding is very much influenced by food availability and access to a suitable mate. Breeding generally occurs around May through to October. However chicks have appeared outside these general times.
6.Do Cassowaries make a nest?
The place that a female cassowary deposits her eggs is perhaps best described as a hollow scrape on the ground rather than a nest. As the male sits on the eggs for almost 2 months this depression can become accentuated.
7.How many chicks can they raise?
Male Cassowaries have been seen with up to 6 chicks in the wild. It is however, very rare for them to successfully rear this number and even less likely for anywhere near this number to survive after separation from the male.
8.How long do male Cassowaries tend their chicks?
While much variation occurs we have noted that nine months is pretty average while the longest time is around 18 months. What can greatly influence this parenting time can be the arrival of a female for the next breeding event.
9.At what age is a Cassowary able to breed?
Once a Cassowary reaches three years of age it begins to attain adult plumage, however the bird is usually about five years old before the skin toning about the head and neck is vibrant, which is an indicator that the bird is mature enough to breed.
10.How long do they live?
Cassowaries have been known to live in excess of 60 years in captivity. However in the wild, where life’s stresses can be more extreme, the figure would be much reduced - possibly to about 40 years
11.Do the Cassowary’s wattles have any function?
The wattles appear to have little biological function other than intensifying in colour with the mood of the bird. Females for example “colour up” when agitated and all the head colours intensify.
12.What do Cassowaries do at night?
Cassowaries are a diurnal species feeding and moving around for much of the day. They are known to revisit camp sites for night periods when they sleep.
13.How large is their home range?
Food availability and bird dominance greatly influence home range size. During the day multiple birds are known to visit the same feed trees (often at different times) on a regular basis but will return to a core area that they appear to defend from other birds. These core areas can be as little as a few hectares up to several square kilometres.
14.How many Cassowaries are there in the Daintree?
The figure has been put at about 60 adult birds in the Daintree lowlands between Cape Tribulation and the Daintree River. This figure is much in need of updating as it is based on survey work carried out in the 1990s.
15.Do Cassowaries only eat fruit?
While the Cassowary is primarily a frugivore it can consume a vast range of other foods, occasionally including some strange objects. They have been observed to eat animal parts, (including small fish and crustaceans), fungi, flower parts, ferns, and the new growth of climbers. After Cyclone Yasi an autopsied bird was found to have a significant amount of grass in its stomach.
16.Are they dangerous?
The Cassowary is a large bird and as such has the potential to cause serious injury if agitated. Cassowaries will usually avoid humans unless their normal reactions have been modified by inappropriate behaviour such as hand feeding. Feeding Cassowaries creates a relationship with the bird that can result in a person being injured when they do not produce the expected food. This has happened repeatedly in areas with heavy tourism activity and the bird has had to be relocated somewhere else. It is also certainly prudent to take care not to intrude on a male Cassowary looking after his chicks as he will most certainly defend them from any perceived danger.
17.How many rainforest trees require their seeds to pass through a Cassowary in order to germinate?
Over a 16 year period volunteers at our nursery successfully germinated most rainforest seeds without the benefit of the cassowary digestion. While seed preparation is often time consuming, our results were usually good. However, when a seed has passed through a Cassowary it has not only had most of its outer flesh removed it is sitting in a lovely pile of compost ready to grow.
18.Is the Cassowary Plum (Cerbera floribunda) only eaten by Cassowaries?
Although the fruit is poisonous there is strong evidence that rodents and fruit bats can and do eat the flesh of the fruit.
19.Are Cassowaries the only creatures who are able to move the larger Rainforest seeds such as Cassowary Satinash (Syzygium graveolens) and some of the larger Laurels such as Beilschmiedia volkii and B. Castrisinensis?
While rodents and fruit bats may not move them a great distance they are able to transport them away from the parent tree which is beneficial to the plants dispersal.