I was finishing my dinner as the sun began to peek through the laurel trees and tall grasses that line the banks of the creek I call home. Having lived here for the past 6 years there have been many alterations to the banks of the creek, and to the level of the water. The banks have become more populated with tall grasses and weeds and the trees have grown taller. The weather has also changed, we got so much rain this season! Some of my buddies decided to head for the lake after all this rain in hopes of finding more tasty prawns and invertebrate critters to munch on. I can’t complain though, the amount of twigs and other debris blown in by the rain and flooding was a real blessing for lining my burrow.
We started the morning perched on the banks of the Peterson Creek located in Yungaburra, Australia. Our goals were to determine how many platypus were potentially in the creek and what their patterns of behavior were. Equally spread along the creek in groups of two, we observed our stretch of the creek three times for an hour and a half each time, hoping to see a platypus. Suddenly, this famous Australian endemic species was spotted peering back at us through the lenses of our binoculars. After the initial excitement of seeing our first monotreme, or egg-laying mammal, subsided, we got to work collecting dive time information. In order to do this successfully, we needed to monitor the timing of the platypus’ movements, specifically the amount of time spent underwater and on the surface.
*Why can’t I hold my breath more than a few minutes?!* I resurfaced for a breath of air before returning to my feeding grounds; again- and again- and again. Ruling this site barren, I made my way around the creek bend in hopes of more success…
After two early mornings and one afternoon of observation, we concluded our time at the creek with a conservative platypus count of four. Compared to past studies at the same site in 2013 and 2017 which recorded six and nine platypus respectively, our results seemed to be conspicuously lower than previous years. Furthermore, the ratio of time underwater to time on the surface was rather large (3.63 seconds:1 second), suggesting a lack of efficiency in feeding, especially compared to the 2017 study ratio of 1.95:1 at the same site. This could be the result of multiple factors, one of which includes the adverse impacts of recent flooding on the abundance of food resources during the annual wet season. Another possible explanation for the decrease in numbers could be the dispersal of individual platypus to the connected dam, which was replenished by the increased rainfall.
I felt the muscle contractions of my prey through the tingling electroreceptors on my bill, indicating that there were aquatic invertebrates and prawns nearby, just waiting to be eaten. I used my agile webbed feet and paddle-like tail to dive to the bottom of the creek to catch them. As I was resurfacing to mash my catch I glimpsed those pesky humans watching me! I swear I see more and more of them each year.
Having had the extraordinary opportunity to encounter these magnificent mammals, we have been overcome with the desire to ensure many others will have this same opportunity. The town of Yungaburra feels similarly; to better accommodate more visitors, they revitalized the creek in the 1990s with improved walking trails, tree plantings, and a viewing platform. With ongoing maintenance, Yungaburra has been able to increase awareness and ensure this ecosystem can continue to sustain a healthy population of platypus. This dedication and the educational opportunity it provides to the general public will help keep them off the threatened species list.
The heat of the sun beat down on my back, which meant it was time to hit the burrow. I waved goodnight to my neighbor down the bank, to the humans in the brush, and slowly made my way to my home-sweet-mud hole on the bank.