Visual methods

plat bin water DSC_0094 (Colin Green)Platypus sightings

The platypus has distinctive physical features and is often active during the day. The places where it lives – lakes, rivers and streams – are also places where humans like to spend their time. Not surprisingly, people observe platypus on thousands of occasions each year.

The development of on-line options for reporting wildlife sightings means that it’s now easy for persons who see a platypus to record the details for posterity. The main remaining challenge is to weed out those sightings that are probably or definitely in error. This mainly occurs when someone sees an Australian water-rat/rakali and believes it to be a platypus – the two species overlap in size and distribution and are a similar colour when wet. Other kinds of wildlife can also sometimes be mistaken for a platypus, such as diving ducks and even large carp. Experience has shown that around 2% of community-based platypus sighting reports are clearly in error, with mistakes occurring more frequently in places where platypus are relatively rare (so people are less likely to know  what the animals look like in the wild). Another 3-4% of reports are likely to be untrustworthy due to the brief nature of the sighting, etc.

It obviously makes sense for websites that record platypus sighting details to do their best to ensure that faulty or potentially misleading records are not included. The following two strategies can be adopted to keep platypus sighting databases as error-free as possible:

  • Only accept sighting records that are supported by photographic or video evidence (for example, as per Canberra Nature Map).
  • Ensure that sighting reports are vetted by a suitably knowledgeable person before being accepted as valid locality records (for example, as per the Australian Platypus Conservancy sightings reporting system). Particularly if a platypus is seen in an unusual setting or unexpected location, it’s essential that the sighting’s circumstances are documented as soon as possible (including if it was the first time that a platypus has ever been seen by the observer, how the animal behaved, and from what distance and for how long it was seen). The benefits of knowing that all records in a database can be treated with a high degree of confidence are clearly enormous, more than offsetting the time and effort required to evaluate them.

Photo courtesy of Colin Green

Platypus Group Watch

vis Plat obs session Aug08 a revPlatypus Group Watch has been developed by the APC to provide a standardised protocol for teams of volunteers to count the number of platypus (and water-rats/rakali) seen in a given water body, ideally at regular intervals (normally entailing one or preferably more sessions per year). Each session typically involves stationing observers (usually in pairs or trios) at 5 to 12 sites distributed along 0.6-2.5 kilometres of stream or river channel. They then scan for animals for one hour near dawn or dusk. Group Watch sessions are most likely to be informative and rewarding if they are carried out in an area where reasonably high numbers of platypus and/or water-rats occur. The Platypus Group Watch methodology has been adopted successfully by a wide range of Landcare and Friends Groups and other organisations, such as ACT Waterwatch, Upper Murrumbidgee Waterwatch and Wildlife Queensland’s PlatypusWatch program.

Along with contributing to platypus and water-rat monitoring, Platypus Group Watch sessions can be a very rewarding social activity. For more details, please contact the Australian Platypus Conservancy to request a Platypus Group Watch information kit.

Photo: APC

Australian Platypus Monitoring Network

vis PlatSpot A Alb 2010MayThe Australian Platypus Monitoring Network (APMN) provides a way for volunteers to contribute to platypus monitoring by visiting fixed monitoring sites of their own choosing to record the number of animals seen there. It has been designed to be a very flexible program, catering to anyone who routinely walks, jogs, rides a bicycle or otherwise spends time along a creek, river or lake where platypus are known to occur. The program is supported by an app and website to simplify the process of recording results, provide personalised feedback about each participant’s own findings, and make the program’s broader findings immediately available via a mapping interface or (if enough data are available to support detailed analysis) bar charts.

For more information about APMN (including an interactive map that shows current and past monitoring sites), please visit the APMN website: www.platypusnetwork.org.au.

Photo: APC