The availability of water in the landscape significantly impacts the presence of fauna including the number of beneficials (insects, birds & bats) present to assist in pest management.
Native vegetation near water sources such as water storages, rivers, creeks, wetlands and even channels are generally healthier and have much higher populations of beneficials and other types of fauna than vegetation that is not near water.
Insects generally get their water from rain drops or dew, however in dry periods such as the current drought they rely more on other sources of water. Waterbirds such as Ibis are common on cotton farms spending their time between water habitats and foraging into surrounding crops for insect pests.
Research undertaken by Adam Smith of UNE during 2014-15 recorded over 55 species of waterbirds on water storages within the Namoi & Gwydir valleys. The highest number of individuals and species of waterbirds were found on storages that were shaped and managed such that a range of habitats (e.g. shallow/deep, vegetated/bare) were available simultaneously. Adam’s results showed that water storages are valuable foraging habitat for waterbirds even in dry periods and are important as additions to the core habitat in natural wetlands where the majority of foraging and nesting occurs.
One of the cotton farms which was part of this study was Pip & Susan Swansbra’s farm “Kurrabooma”, a 3300ha mixed farming and grazing enterprise about 75km west of Moree. “Kurrabooma” has a 1500ML water storage (approx. 65ha) with three islands within the main storage area to help reduce erosion from wave action and evaporation losses. What is unique about this storage, and has contributed towards the diversity of beneficials and fauna found on the farm, is the inside banks of the main storage and islands are vegetated.
Recently, Janelle Montgomery from CottonInfo interviewed Pip to learn more about why they made the decision to leave the vegetation and what the impacts have been on both fauna and management.
“We brought the property in 1984, the previous owners had built three on-farm water storages in the early 1980’s”, said Pip.
“Unfortunately when they first filled Storage 3, it was filled too quickly blowing the western wall. I believe the rapid drop in water level must have left a lot of seed behind, as soon after the inside banks and islands became well vegetated. The western wall was redeveloped and Storage 3 continues to be used as a water storage to this day.
“When we bought Kurrabooma in 1984, the trees were virtually suckers, it would have been a big job to remove them so we decided to leave them.”
The main species of native vegetation found within the storage is Coolibah, Wattles, Cumbungi, Lippia and several species of waterplants such as rushes. The Swansbra’s have not had any problems with the storage walls cracking and believe that this is largely due to the fact that the storage has only ever been completely emptied twice since 1984 and the tree roots seek out the water within the water storage not outside.
“The vegetation hasn’t posed any problems with management, except spraying around the storage because of the trees, however the vegetation definitely holds the bank together and we have never had to maintain the inside bank.
“I think our evaporation must be less too as it does stop the wind across the storage surface,” said Pip.
While not avid bird watchers, Pip and Susan get pleasure in observing the seasonal changes of birds on their water storage. Over the past 35 years they have seen many birds utilising the storage for feeding, habitat and nesting such as jabirus, black swans, a variety of ducks, sea eagles, cormorants, egrets, spoonbills and ibis.
“We have often had magpie geese nest on the storages over the years. They push the cumbungi over and build their nests. If there is any dropped grain about on the farm they will find it. In 2016 we had them at the farm workshop! The magpie geese have been noticeably absent this past 12 months,” Pip said.
Pip & Susan like the fact the birds and other native animals use the storage.
“We get a lot of echidna’s down at the storage too. As it's the most western storage on the farm, it’s the last storage to go dry and when we do get rain, its where the tailwater goes.
“I might not be managing the storage specifically for birds and other fauna, but the fact they are there is great, all the better for our farm,” said Pip
Local farmer and bird enthusiast, Patrick Johnston, has been photographing fauna in the Mallawa/Bullarah district for some time and is often found photographing the birds on his neighbor’s farm “Kurrabooma”. To view Pat’s great photos visit www.bullarah-fauna.pictures.
This blog is part of a year long program from CottonInfo, with the themes aligned with the 2019 CottonInfo cotton calendar. For more information, view the calendar, or contact the CottonInfo Technical Lead for Natural Resources, Stacey Vogel. Image of brolgas courtesy Pat Johnston.