Water Watch regional facilitator Woo O'Reilly warned the mammals might give up on mating this year entirely.

Dry conditions meant less bugs, a vital food source for platypuses in autumn and winter, Ms O'Reilly said.

"Platypuses eat a third of their body weight in bugs every day," Ms O'Reilly said.

"They may just abandon breeding altogether when the resources haven't been there."

"They may just spread out more to forage and and go into marginal habitats to feed."

Ms O'Reilly said "may" because there was still so much that was unknown about Canberra's platypus population.

Luckily, August is Platypus Month for Water Watch. Ms O'Reilly encouraged Canberrans to get involved in one of the 22 volunteer surveys conducted over the month, with the next being Tuesday, August 6.

No experience is necessary and surveys are being conducted across the capital region as far as Cooma Creek.

Ms O'Reilly said they didn't know what a healthy population locally was, so even if four were spotted along a one kilometre section of river, they had no standard to compare to.

"It would be great to see more dedicated monitoring of platypuses to properly understand the status of the numbers," Ms O'Reilly said.

"We've got a survey method that can only tell you so much."

August tended to be the choice month to survey the animal because bug numbers had thinned out over winter, meaning platypuses spent longer periods foraging.

Ms O'Reilly warned people to clean up after themselves near waterways, with plastic rings from milk bottle caps, discarded fishing line and even used balloons having the potential to kill platypuses.

The Bureau of Meteorology released its report on July on Thursday, noting average maximums and well below average rainfall.

July's long term rainfall average was 40.5 millimetres. This July only saw five millimetres at Canberra Airport.

The mean daily maximum temperature at Canberra Airport was 13.7 degrees, 2.2 degrees above the long term average of 11.5 degrees.

Mean minimum temperatures at Canberra Airport were 0.7 degrees, 0.8 degrees warmer than the long term average of -0.1 degrees.

To date, mean maximum temperatures in Canberra in 2019 have been 2.4 degrees above average.