The Ecology of Dingoes in Queensland
An information bulletin from the Land Protection Branch, Deptartment of Lands.
During recent years there have been several detailed field studies into the ecology of dingoes. These studies produced comprehensive information on the movement of individual dingoes through the use of sophisticated radio tracking equipment. The devices allowed researches to locate individual animals at regular intervals over many weeks.
Dingo bitches come inro oestrus esually in April and may (but this may range from March to july). Aftr a nine week pregnancy, the litter of pups, usually from 4 to 6, is born in a hollow log or cave den. Bitches tend to use the same den each year.
While the pups are small, solid food is brought to them from kills made by the parents.
This food may be dragged or carried back, or part of it swallowed by the parents and later regurditated for the pups. Some litters are reared by both parents and some only by the bitch.
When the pups are large enough to travel, they are taken from the den to kills and eventually other dens are used. The range of the pups is increased as they are moved from one den to the next. It has been observed that some bitches move pups from one den to the next in an order that is repeated each year. It this way the pups are moved around much of the range of the bitch.
Pups may become independant of their parents as
early as six months of age or as late as twelve months. In the former case independance is forced on the pups when the parents abandon them.
Morality of juveniles is high when pups become independant at an early age and few survive to adulthood. Conversely, the pups that become independant around twelve months appear to disperse voluntarily from the parent-offspring group and by then are larger and more experienced, and hence, morality is low.
From the radio tracking studies mentioned earlier, it is understood that the dingo visits the edge of his district or area frequently, thus recognising a boundary. This area, termed a "home range", varies in size depending generally on the productivity of the country.
In dissected and forested areas in northern New South Wales, the home range of adult dingoes was calculated to be between 25 and 50 square kilometers, and in arid parts of Western Australia, home ranges vary from 70 t0 150 square kiometers.
The edge of the home range is commonly associated with a major topographic feature, such as the edge of an escarpment, a major ridge or a major stream.
Dingoes do not use their home range uniformly. The areas most extensively used by dingoes are usually the areas of the highest macropod (food source) density.
The home range is used as a series of sub units, a number of days being soent in each. during each day's activities, a part of the perimeter of the range is usually visited. Movement around the major pathways (tracks, ridges and streams,) i.e., the perimeter of the home range, is rapid and is in contrast to the slow moving, exploratory movement associated with hunting.
These pathways generally correspond with what dingoes describe as the dingoe's regular beat, and are most likely to be associated with sociality and home range boundary maintainance.
Dingoes operate in small groups, the cohesion of which varies in different circumstances.
The group rarely moves as a pack, rather members meet and separate again throughout the day.
Within a group there is a considerable overlap of home ranges. However, the boundaries between the groups are much more rigid, actively defended, and are only infrequently crossed. At high densities, where group cohesion is highest, there appears to be a reduction in the number of females which breed.
Group cohesion is maintained by various means of communication. Olfactory communication
(smell) plays an extremely important role in the social organisation of dingoes. Faeces are dropped along pads in specific areas. These are usually places such as creek or river crossings, intersections of pads and so on, areas where other groups or individuals will encounter them.
It is suggested that these "scent posts" delineate the home range boundary and serve as a "keep out" warning to neighbouring groups and individuals.
Studies into the diet of the dingo have been undertaken from detailed examination of stomach contents or faecal scats. In each case dingoes had taken a wide range of prey. However, macropods (kangaroos and wallabies) consistantly occupied the greater portion of their diet.
Dietry studies suggest that dingo predation on domestic stock is low, ranging from one to seven percent. However, the results of dietry studies must be treated with extreme caution when assessing the impact dingoes have on domestic stock
Studies by the Agriculture Protection Board in Western Australia reported that dingo groups in undisturbed refuge areas, caught and killed kangaroos and ate them stricly according to their needs.
On grazing country, "the dingoes harrassed, bit or killed sheep in large neumbers, often without eating any". the consumption of sheep carcases was the exception rather than the rule. Even kangaroos were sometimes killed by these dingoes as a game, rather than for food.
Furthermore, dingoes at 'play' appear to select individuals that are stronger, more healthier and 'fleet of foot', rather than the weak and feeble. This behaviour is the main economic impact of the dingo. It should be noted that if dingoes only killed sheep and calves for food, their impact would be relatively insignificant.
PEDESTRIAN: A motorist with teenage sons.