*This article was first published by the Cumberland Bird Observers Club in February 2015.
The marriage of farming and wildlife conservation is as captivating as it is necessary. It’s what drives the Bitterns in Rice Project, now in its third season, and it was a key motivation behind the humbling support we received during the Tracking Bunyip Birds campaign in spring last year.
The Australasian Bittern is one of our country’s most threatened birds. They are considered nationally and globally Endangered, perhaps with just two or three thousand remaining. They are also among our most poorly known bird species. The association between the legendary Bunyip and the booming call of breeding males is no coincidence. The sneakiness and near-mythical nature of the species was perhaps best illustrated in 2012 when John Weigel broke the national birding record, held for a decade by Sean Dooley. He travelled extensively and found a whopping 745 species, but he did not find a Bunyip Bird.
A trip to the rice crops of the NSW Riverina would have produced the goods. For decades we’ve known that bitterns use these rice crops, yet only now as a result of extensive surveying are we beginning to appreciate the significance of the population. We continue to crunch the numbers and expand our surveys of randomly selected rice farms, but it’s evident that in most rice growing seasons a population of somewhere between 500 and 1000 descend on the rice in late spring, approximately two months after sowing. We’ve also learned that there is widespread breeding. Encouragingly, from the nests found so far, it appears that there is sufficient time for the chicks to fledge before harvest, which normally peaks around April.
I’ve been chasing bitterns in wetlands across the Riverina since the late 1990s and I’m still coming to grips with the fact that my best results by far have come from agricultural wetlands; completely constructed habitats that produce food and support an impressive biodiversity. I wouldn’t be nearly as excited about the prospect of farming and wildlife conservation working together here if it involved just this one species. However, it doesn’t take much surveying of Riverina rice fields to realise their value for others. Notably, Glossy Ibis and Whiskered Tern occur in their tens of thousands. More familiar waterbirds, such as White-necked Herons and Pacific Black Ducks, are there in big numbers too. Less obvious are the populations of Baillon’s Crakes and Golden-headed Cisticolas, again extending well into the thousands. There are migratory shorebirds like the Sharp-tailed Sandpiper and Latham’s Snipe that also make widespread use of rice fields.
Probably of most interest to birders are the Eastern Grass Owls that we documented roosting in rice crops last season. There were at least five of them. Previously only expected in the north-east of the state, subsequent anecdotes from rice growers suggest these owls may have also been overlooked in rice crops until now. I’m certainly hoping to turn up some more this season. Funnily enough, one was found roosting within metres of a bittern nest and I feared the worst: bittern chicks on the menu. Fortunately, I needn’t have worried, with two ~18 day old chicks relocated on a bank, already 50 metres from the nest. Beyond waterbirds, and speaking of threatened species eating each other, rice crops in parts of the Riverina, such as Coleambally and Wakool, support significant populations of the nationally Vulnerable Southern Bell Frog (also known as the Growling Grass Frog). Peter Menkhorst watched an Australasian Bittern eat 17 of them at Werribee so it’s a reasonable assumption that they’re an important food source for bitterns in some rice crops.
Perhaps just as surprising as the owls has been the use of rice fields by the Australian Painted Snipe (APS), our only other waterbird species considered Endangered at the national and global level. For wader enthusiasts and others interested in more detail, see the forthcoming issue of The Stilt. In a nutshell though, during the 2012-2013 rice season, a total of 87 APS were recorded at eight widely distributed Riverina rice fields. It’s highly likely that they were indicative of many more, probably at least several hundred, because of the limited survey effort and coverage.
So on top of the largest known population of the endangered Australasian Bittern, it’s easy to see the potential for agriculture and conservation – two traditionally separate schools of thought – to work together here. Protected areas like national parks, and the most intact parts of the landscape are vital to conservation, but it’s clearer than ever that alone they’ll be vastly inadequate in waving off the forecast extinctions. The challenges ahead are enormous, and with about 200 000 extra mouths to feed each day on our pale blue dot, population growth and food security are good places to start. Concerted efforts in family planning, the retention of girls in school, reduced meat consumption and food waste, and more food production in urban areas, will all help reduce demand. However, we’ll still need much more food as this century rolls on. Modern history has shown that increased food production almost invariably equals less biodiversity, but this needn’t be the case.
One of the major outcomes of the Bitterns in Rice Project to date has been the development of our first edition of Bittern Friendly Rice Growing Tips. They are based on our key findings so far, such as the preference for early, aerially-sown crops, as opposed to combine/drill-sown crops that have dry phases and delayed permanent water. The tips have been widely distributed and a heartening, growing number of rice farmers are incorporating them into their management. Thanks to the generosity and goodwill of one particular grower this season, we’ve begun a pilot study to test the effectiveness of some of the tips across five 3-hectare bays. One is pesticide free; two with only minor early treatment for bloodworm and barnyard grass; and two with management as normal. We’re looking forward to expanding these trials to include the necessary replication of treatments. Plans are also underway to trial dedicated habitat bays incorporated into a rice field that can be managed independently and beyond the rice growing season. The bitterns are our priority, although we’re mindful of the potentially conflicting habitat preferences of different species. For example, sympathetic management of barnyard grass on the banks between bays may provide roaming bittern chicks with cover and improve breeding success, but be bad news for shorebirds including the APS.
Now let’s get back to the burning question: when these approximately 750 bitterns descend on the rice crops for a summer of breeding, where do they come from, and after harvest, where do they go? Thankfully, following the success of the Tracking Bunyip Birds campaign, all will soon be revealed. Surveys during the off-season last year suggested some stay locally and are quite mobile during these colder months, however it appears the majority of the population leave the Riverina. Soon we’ll have a dedicated Bitterns in Rice Project website, and from here people across the world will be able to follow the movements of “Vin”, “Julia”, “Bully”, “Robbie” and the rest of the gang. We’re hoping to be able to begin tracking our first bitterns before this present rice season finishes, pending permits, approvals and transmitter availability, but we may have to wait until next season. In any case, it’s going to be very interesting and downright exciting. Among other things, we’ll learn which wetlands are important for this significant population during the non-breeding season, and whether or not bitterns recorded in areas like south-western Victoria are the same birds that use the rice.
Crucially, the Bitterns in Rice Project has the support of hundreds of rice growers across the Riverina. They feel the habitat values of rice fields are finally being recognised, and many are delighted with the idea of producing food and conserving threatened wildlife at the same time. Again, the marriage of farming and wildlife conservation is as captivating as it is necessary. The false dichotomies of farming and the environment, the economy and nature, us and them, greenies and farmers, urbanites and country folk, humans and biodiversity, all stymie the path to sustainability and deny the existence of a single superorganism: life on Earth. We’re all in this together.
Matt Herring is a wildlife ecologist at Murray Wildlife, and through the Bitterns in Rice Project (BIRP) he works closely with Neil Bull, Andrew Silcocks, Mark Robb, Anna Wilson, Max O’Sullivan, Keith Hutton and others on the BIRP committee.
For social media users, you can ‘like’ the Bitterns in Rice Project on Facebook for regular updates, or follow Matt on Twitter @Matt_HerringOz
The Bitterns in Rice Project is a collaboration between the Rice Growers’ Association of Australia and Birdlife Australia, with key support from the Riverina Local Land Services (LLS), the Australian Government’s Rural Industries and Research Development Corporation, the Norman Wettenhall Foundation, Coleambally Irrigation, the Murray LLS, Murrumbidgee Irrigation, Murray Irrigation, Murrumbidgee and Coleambally Landcare, the Murrumbidgee Field Naturalists Club, and the NSW Office of Heritage and Environment.