Echidna: Social Structure

Summary: Do echidnas ever get on each others nerves? Join Kiersten as she talks about the social structure of echidnas to find out!

 

For my hearing impaired listeners, a complete transcript of this podcast follows the show notes on Podbean

 

Show Notes: 

Short-beaked Echidna. Bush Heritage Australia, https://www.bushheritage.org.au

Eastern long-beaked echidna, Animalia, https://animlia.bio

“Home Ranges, Movement, and Den Use in Long-beaked Echidnas, Zaglossus bartoni, From Papua New Guinea,” by Muse D. Opiang. Journal of Mammalogy, Volume 90, Issue 2, 14 April 2009, pages 340-346. https://doi.org/10.1644/08-MaMM-A-108.1

Music written and performed by Katherine Camp

 

Transcript 

(Piano music plays)

Kiersten - This is Ten Things I Like About…a ten minute, ten episode podcast about unknown or misunderstood wildlife.

(Piano music stops)

Welcome to Ten Things I Like About… I’m Kiersten, your host, and this is a podcast about misunderstood or unknown creatures in nature. Some we’ll find right out side our doors and some are continents away but all are fascinating. 

This podcast will focus ten, ten minute episodes on different animals and their amazing characteristics. Please join me on this extraordinary journey, you won’t regret it.

This episode continues echidnas and the seventh thing I like about them is their social structure. 

Overall, all species of echidnas are solitary animals. They spend the majority of their lives alone, only coming together during breeding season. Then mothers will remain with the puggles until they are about 7 months old and they are able to leave the den and forage for themselves. Outside of breeding season and puggle-raising duties, echidnas live solitary lives.

We do base this information on what we currently know about this enigmatic creature which, sadly, is not a lot. They are hard to study in the wild because they are typically nocturnal and they often dig dens that they stay in during the day. Researchers haven’t given up and do continue to try and learn as much as we can about their everyday lives. 

A study published in 2009 looked at the home ranges and movement of the eastern long-beaked echidna, Zaglossus bartoni. The study showed that mature adult home ranges did not overlap with each other, but juvenile echidnas occasionally overlapped with female echidna home ranges. It is possible that these juveniles may have been the offspring of the females, but that was not proven.

Home range size was estimated for 11 individual echidnas. Seven were positively identified by sex and 4 were estimated, giving a total of seven females and four males with three juveniles. Researchers strapped telemetry anklets to the subjects to document as many points as possible to estimate home range size. By the end of the research period, home ranges sizes varied from 2.2 hectares to 168.2 hectares. 

If you’re thinking that’s quite a large difference in home range sizes, you’d be right. Let’s look a little closer at these results. The individual with the smallest home range size only had 4 points of reference, so we’d probably throw that one out because of lack of data. The largest home range of 168.2 hectares was a juvenile with 43 points of reference, so most likely this is a good estimate of the home range. Because it’s a juvenile, the researchers believe that it was still trying to decide on a home range and that’s why it was wandering so far and wide. Most likely this is not indicative of a typical echidna home range size. This individual was also the one that overlapped with other home ranges.

The more median size home range is what we’re really interested in. This gives us a better idea of the typical home range size of the average eastern long-beaked echidna. If we add all the home ranges together and divide we get and average of about 25 hectares. This is a pretty good size home range, lots of area to find insects to munch on and a nice place to find a den.

Interestingly, the home range with the most points recorded was a size of 75 hectares for an adult female. Considering this individual was recored with 65 points of reference this might be a more typical home range size, but it could also just be this individual’s preference. This study was incredibly interesting and a great start to mapping out the needs of the eastern long-beaked echidna.

So what makes a good home range? There are a few necessities that a good home range must contain. Food is definitely important. You must have enough food to sustain yourself before you settle down. Water is also important, but echidnas do not rely on standing bodies of water as much as other mammals. They can get water from the food they eat. The last thing that is incredibly important in a home range is a place to make a den.

During this study, 223 dens of long-beaked echidnas were found. 209 of them were underground dens. Of the ones found above ground, it appears that most of them were utilized by juvenile echidnas. Maybe there is a learning curve for how and where a great den is created. Or the juveniles hadn’t established a permanent home range, yet.

When creating a den the echidna will dig out a main resting place with two separate entrances. That’s good thinking there, always have an escape hatch. If at all possible these dens will be located on the side of sloped earth. It may be easier to dig into a sloped mound and it can also help keep the den from becoming flooded. Boy! These echidnas really know how to build the perfect house!

Whenever I find out that an animal that mates with others of the opposite sex leads a solitary life in a fairly large home range, I know I always ask How do they find each other when it’s time to make babies? I asked this question about the echidna. So how do they find each other? Through scent. When breeding season begins both males and females emit a scent that attracts the opposite sex to them.

Most of the responsibility of finding another echidna lies on the male, and as we discussed in the reproduction episode, he’ll travel quite the distance to ensure that he’s the mate for her. The spur that all echidnas have at some point in their life may have originally been used for venom like the male platypus, but now it’s used for secreting a substance that may attract females during mating season.

The last thing we need to discuss about echidna’s social lives is what happens when they encounter each other outside of breeding season. And that appears to be not much. No sources that I’ve used for this series have said anything about echidna on echidna aggression. It seems that when they do encounter each other outside of the breeding season, they just kind of avoid each other. During breeding season, the worst a male will do to another male is push them out of the love train. No blood and guts death matches for echidnas. 

That’s it for the social structure of echidnas. Thanks for listening to this episode because the social lives of echidnas is my seventh favorite thing about them.

 

If you're enjoying this podcast please recommend me to friends and family and take a moment to give me a rating on whatever platform your listening. It will help me reach more listeners and give the animals I talk about an even better chance at change. 

 

Join me next week for another episode about echidnas.    

 

(Piano Music plays) 

This has been an episode of Ten Things I like About with Kiersten and Company. Original music written and performed by Katherine Camp, piano extraordinaire.