But Tasmanian researchers have discovered the spiky mammals aren't particularly careful at all. Gemma Morrow from the University of Tasmania has spent three years digging up echidnas and using ultra sound to study their mating habits.
As well as having echidna orgies, some male echidnas try to mate with females who are still hibernating. Co-researcher Stewart Nicol says the project has uncovered important information about how egg laying mammals reproduce. It's hoped the information gathered by the research can be used to help conserve their relatives, the endangered long beaked echidnas, in Papua New Guinea.
It might also protect echidnas if they one day succumb to a deadly illness like the Tasmanian devils' facial cancers. This article is more than 5 years old. Echidnas are found all over Australia but are difficult to track because they live in dens.
Men who kidnapped Piggie the echidna had hoped to find crocodiles. Think you know everything there is to know about short-beaked echidnas? Test your knowledge with these fun facts. South Australia is home to lots of amazing native species , and these guys are no exception. Here are some fun facts:. Believe it or not, the spines you see on an echidna are actually long, tough, hollow hair follicles.
Of the 4 young that were radiotracked, 2 died before reaching 24 months of age. Little is known about young echidnas after they leave the nursery burrow. Dispersal from the natal area is a logical strategy for new recruitment and genetic mixing. On Kangaroo Island, belts of remnant vegetation exist that allow dispersing animals to move great distances in relative safety.
We found 17 1- to 2-year-old subadults during the course of our study. We concluded that that was a true indication of recruitment through migration because marked subadults hatched in the area were not found in the study site after dispersal.
Further, all subadult echidnas in a study conducted in Western Australia dispersed from the study area when they were 12—16 months of age Abensperg-Traun Our findings clearly support this dispersal theory.
Six of the 17 recruited subadults died within the study period. If we hypothesize that young whose fate were unknown survived to disperse, recruitment nearly equaled the number of young that left the area.
Little is known about naturally occurring illnesses in echidnas Griffiths ; McOrist and Smales Dissection and necropsy showed no internal abnormalities or parasites. Two other recruited subadults were killed by cats, and we speculated that the remaining 2 deaths were caused by chemicals.
In 1 part of the study area, a color-marked herbicide targeting a feral plant was used for 2 years. During the spraying program, 2 subadults Table 6 and 3 adults, not mentioned in this study, that foraged extensively in the sprayed area died. Cause of death could not be verified conclusively, but all dead animals had spotty discolored livers and enlarged spleens.
Effects of herbicides and pesticides on echidna food sources, namely invertebrates, are unknown. No relationship was found between body mass of the female and number of suitors in a train.
We have yet to identify the existence of a relationship between body mass and success of breeding males Table 3.
In 14 of 15 trains examined in an earlier study, the female had the greatest body mass Rismiller Our current, long-term study showed that this pattern may vary annually. For males, the greatest body mass loss was during the breeding season. Maximum body mass of reproductively active males and females ranged from 3, to 4, g. However, females that were lactating and carrying a young had a slight drop or leveling off of body mass toward the end of the year. One exception was the largest female, whose minimum body mass was greater than the maximum of other females.
Another female's body mass increased toward the end of the year after her young was killed by a cat. In both sexes, highest body masses were reached in January—March. Fluctuations in seasonal body mass in echidnas living in a cold climate were slightly shifted, with the peak occurring in April and the low in November Beard et al.
The significance of body mass fluctuation in the breeding ecology of echidnas is not clearly understood. What physiologic factors and environmental signals cue reproductive responses in echidnas are still unknown.
Loss of a young before weaning does not influence sexual activity of a female in the next breeding season.
Size, number, and duration of trains do not seem to play significant roles in reproductive success. We would not expect an environmental cue such as rainfall to influence reproduction because echidnas throughout Australia breed in June—September, which is the wet season in the southern part of the country and the dry season in the north.
However, reproduction may be related to photoperiod because both free-ranging echidnas in Australia and those kept in captivity in the northern hemisphere have highest reproductive activity between the winter solstice and the spring equinox.
Our study reinforces the fact that Tachyglossus demonstrates a high degree of adaptability and individualism. This study shows that 7 years is not sufficient to conclusively determine frequency of breeding, survival rates of juveniles, recruitment of subadults, or effects of feral predators on population dynamics of echidnas. However, we propose that infrequent breeding, dispersal of young, and predation in our study are indicative of conditions for populations of short-beaked echidnas throughout Australia.
This project was supported by Earthwatch Institute throughout its duration. We gratefully acknowledge technical support of Biotelemetry Tracking and Canon Australia. We appreciate the helpful comments from reviewers on an earlier draft of this manuscript. Abensperg-Traun M. A study of home range, movements and shelter use in adult and juvenile echidnas Tachyglossus aculeatus Monotremata: Tachyglossidae in Western Australian wheatbelt reserves. Australian Mammalogy 14 : 13 — Google Scholar.
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