2013 diary summary Richard Underwood Nature Refuge
A drier year
This year was drier than recent times, with the Richard Underwood Nature Refuge receiving 200mm of rain—only a third of the average annual rainfall of about 600mm. Wombats are well adapted to dry conditions due to their slow metabolism and low energy expenditure. Hence, the wombats found plenty to eat and maintained their good weight and a healthy body condition through the year.
A trial of providing supplementary feed for wombats began in the latter part of the year in preparation for the drier months ahead. It is better to slowly introduce the wombats to a new food source so they are familiar with the type of feed that will be offered if drought conditions persist. The wombats have shown little interest in the supplementary feed, instead preferring to forage for their food.
With summer daytime temperatures in excess of 40 degrees and night-time temperatures in the high 20’s, the wombats displayed low levels of activity; emerging late in the evenings to take advantage of the coolest hours for foraging.
Over the summer months, the wombats were observed spending an increased amount of time lying down and sleeping at the front of their burrows throughout the night. Lying in freshly dug earth assists the wombats with cooling down.
Another behaviour that peaked over the summer months was dust-bathing; the wombats throw dirt over themselves and sometimes even roll in the dust. This behaviour probably helps the wombats to relieve the symptoms of parasites such as ticks and fleas that are common during the warmer months.
Monitoring biodiversity at the nature refuge
As well as managing for the needs of wombats, Richard Underwood Nature Refuge is also managed for biodiversity. It is important to maintain the biodiversity of the site, including all the species of plant and animal that naturally occurs there.
As part of the biodiversity monitoring, periodic fauna surveys are undertaken in order to document species presence, abundance and diversity. The presence or absence of species acts as an indicator of the overall health of the ecosystem. Undertaking fauna surveys at regular intervals enables any changes to be detected over time.
During summer, a number of departmental employees undertook an extensive fauna survey within the nature refuge. A number of new species were recorded for the site, including reptiles, amphibians, birds, mammals and insects.
Monitoring wombat habitat
Monitoring the habitat quality at Richard Underwood Nature Refuge is as important as monitoring the wombat population. With the potential for introduced buffel grass (Cenchrus ciliaris) to out-compete native grasses, long-term monitoring of the changes in pasture quality and habitat structure is essential.
In 2013, a survey was undertaken to record the current vegetation biomass at the nature refuge. This carries on from survey work initially completed by the Queensland Herbarium around the time Richard Underwood Nature Refuge was gazetted in 2008. The location of each survey site has been permanently recorded, so they can be resurveyed every few years.
Taking photographs of each survey site will assist with documenting changes in vegetation quality over time. The most recent survey recorded an average ground covering of 33% native grasses, 37% buffel grass and 30% bare ground. This long-term biomass survey is in the early stages and it is too soon to report on changes in the vegetation structure.
A quiet year for wombats
Surveillance camera footage continues to be collected daily at Richard Underwood Nature Refuge to monitor wombat health and behaviour. Following the losses in 2012, there was no apparent conflict between wombats in 2013 and all observations are of a more harmonious wombat population at Richard Underwood Nature Refuge. In 2013 there were no births or losses in the colony; maintaining a status quo for the time being.