Outing Report: March 2017: Wyreema Wetlands

Our morning at Wyreema was an excellent follow-up to Mick Atzeni’s talk of Friday night. The whole project was much easier to conceptualise when we could see the true scale of it, and get a feel for the lie of the land.

John Mills from Toowoomba Regional Council was kind enough to come and explain to us the ins and outs of sewage treatment generally, and what the changes in Toowoomba’s sewage management mean for the Wyree-ma wetland. It was particularly interesting to have him explain just why it was a good idea to pipe sewage all the way to Wetalla. Apparently Toowoomba previously had a poor record of letting too much nitrogen and phosphorus flow into the Murray-Darling river system, and was a major contributor to the serious problem of blue-green algae. Major changes to Wetalla’s processing method mean that we can now be proud of the clean water that we send down the river. John also brought up the subject of increased “hard-pan” – the increasing area of land under hard surfaces, such as buildings, roads, and driveways – which results in increased stormwater run-off. This will affect the wetlands site.

The Wyreema plant still has a function. It receives the sewage from Wyreema and Cambooya, and sends it on to Wetalla, so a small corner of the site will continue to be involved in this. TRC’s decision is still to be made as to what can be done with the remaining area, which consists of a large area of open land, the old sewage ponds, and the dam which now collects Wyreema’s stormwater run-off.  The stormwater dam will continue to attract birds, but it is still to be decided to what extent TRC might feel able to support the restoration of the area to the high-quality wetland it was, when the sewage treatment ponds were in use.

These shallower ponds provided excellent shallow-water feeding-ground for wading birds. We could also see that unlike the steeper-sided stormwater dam, they provided an excellent habitat for rushes and sedges, which in turn provided nesting sites and shelter for birds.

Members discussed several issues with John, including the TRC’s perceived need to remove sludge from the ponds as part of the process of restoring the land to an acceptable state. John pointed out that sewage works are subject to requirements in this regard, similar to those for mines.

Members queried the necessity of this, considering that birds had been using the habitat, without apparent harm, for 20 years. They also suggested that increasing the pond area, and therefore the seepage area, could be a way of contributing a local solution to the problem of reduced groundwater recharge because of rapidly increasing hard-surfacing of the land. As the increasing local difficulty of accessing bore water demonstrates, it may be that sending all that potential recharge water away downstream is not the happiest solution. Meanwhile, the birds would benefit from the resultant wetlands. Thank you to both John and Mick, for a morning which was both enjoyable, and left us feeling much better-informed about the Wyreema Wetlands issues.

Visiting by Yourself

It is possible to look at the wetland’s birds from outside the fence at any time. This only gives a view of one of the ex-sewage ponds, but because it is shallow, it is the best one for wading birds. The deeper stormwater dam can only be seen from inside the fence, but you can ONLY enter the precinct if you follow certain Toowoomba Regional Council requirements. If you would like to do it, would you please contact Mick Atzeni first to find out about them? It would be helpful to the success of the project, if you could let Mick know of any birds you see there. His email address is: tiddalac@gmail.com

(Report by Patricia Gardner)

Birds, Frogs and Dragonflies List compiled by Al Young

Yellow rumped Thornbill (or 'butter bum')
having a bath at Wreema (photo: Al Young)

Birds – Pacific Black Duck, Grey Teal, Straw-necked Ibis, White-faced Heron, Black-shouldered Kite, White-headed (Black-winged) Stilt (1),  Masked Lapwing, Black-fronted Dotterel (8), Rock Dove (Feral Pigeon), Crested Pigeon, Nankeen Kestrel, Brown Falcon (Hodgson Cr), Cockatiel, Red-rumped Parrot, Pale-headed Rosella, Yellow-rumped Thornbill, Grey Butcherbird, Pied Butcherbird, Australian Magpie, Black-faced Cuckoo Shrike (Hodgson Cr), Willie Wagtail, Magpie-lark, Torresian Crow, Golden-headed Cisticola, Zebra Finch and Australian Pipit. (Taxonomy follows the International Ornithological Congress, 6.3, 2016)

Frogs: Two species of frogs were heard calling in a patch of rushes in Hodgson Creek. They were Spotted Grass Frog (Limnodynastes tasmaniensis) and Striped Marsh Frog (Limnodynastes peroni). The call of the Spotted Marsh Frog is like a short machine gun burst –‘Burrup Burrup’, whereas the Striped Marsh Frog makes a soft ‘toc-toc’ call.

Dragonflies along Hodgson Creek, Cambooya:

There was a considerable amount of dragonfly activity, mostly associated with ‘begetting’, near the remaining pools of water in Hodgson Creek. Males were actively patrolling their territories with some males and females flying in tandem thus allowing the females to deposit eggs into the water. I managed to identify four different species of dragonflies with a further two or three species of medium-sized dragonflies unidentified because they didn’t perch to allow a photo to be taken. Interestingly there were no damselflies present.

Australian Emperor (Hemianax papuensis)
Male and female flying in tandem

Blue Skimmer (Orthetrum caledonicum)

Scarlet Percher (Diplacodes haematodes)
No dark markings on a scarlet
abdomen

Wandering (Common) Percher
(Diplacodes bipunctata). Note: dark
markings on a reddish orange abdomen

(Photos by Al Young)

THE GRASSLAND AT WYREEMA WETLAND

(Article and photo by Patricia Gardner)

At our March meeting, Rod Hobson and Bruce Lawrie told us that the vegetation around the ponds might include some good quality Queensland Bluegrass grassland, a Regional Ecosystem type (11.8.11), which is classified as “of concern”. Because of the dry weather, they found it difficult to be sure when they visited, a few weeks ago. They remarked on the importance of grasslands as ecosystems and the tendency for them to be undervalued in comparison with treed ecosystems. They expressed the hope that if further investigation showed the Wyreema wetland to have value as a grassland, any planting of trees would be carefully restricted to prevent damaging it.

On our outing, we found it similarly difficult to get a good idea of the full range of plants there, though because of the recent rain it was looking a little healthier than when Rod and Bruce saw it. Given that many of our local grassland plants either die back to their perennial underground roots in dry times, or have seed that won’t germ-inate until good rain comes, there are likely to be more species there than we saw.

Blushing bindweed (Convolvulus erubescens

There was certainly plenty of Queensland bluegrass Dichanthium sericeum there. Other grasses included Yabila grass (star grass) Panicum queenslandicum. There were very few native trees, but we saw Mountain coolibah, Eucalyptus orgadophila and Sally Wattle, Acacia salicina. These species, and their very sparse distribution, are both typical of R.E. 11.8.11.

Healthy grasslands always contain a good population of

wildflowers. We saw blushing bindweed Convolvulus  erubescens; sensitive plant Neptunia gracilis; plover Daisy Leiocarpa brevicompta; tah vine Boerhavia dominii; yellowtop daisy Senecio pinnatifolius (AKA Senecio lautus) and maloga bean Vigna vexillata (the little yellow pea). We also saw a good scattering of Austral cornflower Rhaponticum australe (AKA Stemmacantha australe), the vulnerable plant mentioned by Mick on Friday night. These little grassland forbs are all good butterfly host plants.