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When the Ghost Gum Peels, Bull Sharks Are Fat in the River

When the Ghost Gum Peels, Bull Sharks Are Fat in the River

By Emma Woodward

With indigenous knowledge being lost, six Aboriginal language groups have documented up to 13 “seasons” that can be used by scientists to evaluate the impact of climate change.

Aboriginal and Torres Strait Islander knowledge of their environments combines meteorological, hydrological, biological and spiritual observations to create a knowledge system that is unique and complementary to a western scientific understanding of the world around us.

A common feature of this indigenous understanding of the environment is the connection between seemingly unrelated plant and animal species. For example, speakers of the Ngan’gi languages of the Daly River in the Northern Territory look for the flowering of the red kapok tree to tell them that freshwater crocodiles are laying their eggs and it is time to go and dig them up. Once the seed pods of the same tree turn brown and crack, the crocodile eggs are hatching and the collection season has finished.

In contrast to the Gregorian calendar, which follows pre-set calendar dates for months and seasons, indigenous seasons are defined by one or more events that herald the arrival of a new season. These events, or seasonal cues, can be a combination of ecological, meteorological or metaphysical observations.

For example, eight of the 13 seasons in the Ngan’gi seasonal calendar follow the lifecycle stages of the local speargrass species (Sorghum intrans), and are therefore directly correlated to annual variability in rainfall. Seasonal cues like this inform indigenous people about the availability of specific food resources and guide subsequent harvesting behaviour.

For the past 5 years I have worked with the senior elders of six Aboriginal language groups from tropical Western Australia and the Northern Territory to document indigenous seasonal knowledge. As a result of the work, a portion of each of the language groups’ knowledge of the annual cycle of seasons has been captured in six seasonal calendars that show the key plants and animals hunted and gathered through the year, specific uses for different bush resources, and techniques for their collection and preparation.

Indigenous ecological knowledge is built from acute observation of the local environment, and includes knowledge of the life-cycle stages of the local plant and animal species, local weather patterns and the hydrology of nearby rivers and water holes. This ecological knowledge base is unique to each language group, and has been built over long periods of time and handed down from generation to generation.

Common to each language group is a detailed set of ecological indicators that act as cues for the targeting of specific plant and animal resources, with many falling into the category of phenological knowledge. Phenology is the term used to describe biological seasonality, including the observation of life cycle events and changes in specific plant or animal species.

Phenological events generally occur in consistent order, with the arrival of one event predicting the onset of another. As such, they can be thought of as stable biological timepieces that respond to seasonal variation between years.

Indigenous people use phenological events to predict the timing of growth stages in other species, as well as to shape conceptions of time as they relate to seasonal change and spiritual beliefs about the cause-and-effect relationships of seasonal change.

Phenological knowledge is of particular interest to western scientists because of its direct link to meteorological patterns and its potential use in indicating climate change. It is also attracting interest worldwide as a monitoring tool for broader environmental change.

The six language groups that worked on the calendars were the Gooniyandi and Walmajarri from the Fitzroy River area in the Kimberley region of Western Australia, the Ngan’gi, Malakmalak and Wagiman from the Daly River region in the Northern Territory, and the Gulumoerrgin/Larrakia from the Darwin region.

I came to work with these language groups as part of a larger Tropical Rivers and Coastal Knowledge research project that sought to understand how Aboriginal people value Australia’s tropical rivers, and how these values might be included in government water planning processes. Such values include significant social, cultural and economic benefits.

The research found that Aboriginal people in the Daly and Fitzroy catchments, where the research primarily focused, target specific plant and animal species in an annual cycle of hunting, fishing and collection of bush foods. What captured my interest was the seasonal cues and other environmental observations that Aboriginal people drew on to make decisions about when to hunt and fish the varied habitats of their local environment.

Given the oral nature of traditional Aboriginal culture, this was the first time that much of the participants’ environmental knowledge had been articulated into English and put down on paper. Elders of each language group were motivated to engage in the research process through a grave concern that their knowledge was being lost as older generations passed away. For many language groups, fewer young Aboriginal people are being skilled up in this knowledge, a result of fewer opportunities to spend time learning about country with older family members.

The way in which the seasonal knowledge might be displayed, as a highly visual circular wheel of environmental knowledge and seasonal understanding, also drew strong interest from participants. The colourful poster format is particularly useful for engaging younger generations.

So what exactly does this knowledge look like?

The Ngan’gi Seasonal Calendar

The Ngan’gi seasonal calendar from the Daly River region includes the following seasonal resource use indicators.

During the season known as Ngunguwe, which translates to “mirage”, it is very hot and humid, with no rain. Mirages can be seen during the day and the ghost gum bark starts peeling, letting you know that bull sharks are fat in the river. The river is really low now and the depth of the river indicates it is a good hunting time for stingrays and sawfish.

Following the first rains of the wet season, speargrass seeds begin to germinate and people know that Misyawuni, the bush potato, is available for gathering.

The dry season has truly started when the wind blows from the east and speargrass seeds have turned brown and start falling to the ground. This season is known as Wurr bengim miyerr. It is the dragonflies that indirectly bring the wind, as their arrival wakes the big black kangaroo (Agurri) that lives in the hills who then sings the wind, blowing it from the east. The appearance of dragonflies (Ayiwisi) tells people it’s a good time for barramundi (Atyalmerr) fishing.

During the wet period, access to hunting and fishing places is limited due to flooding. Animals also disperse within the flooded landscape, making them more difficult to hunt. Less availability of food resources results in fewer phenological events and thus fewer season names for this part of the seasonal calendar.

According to the Ngan’gi seasonal calendar, hunting and gathering of resources starts in earnest toward the end of the wet season with the collection of fruits during the season of Wudupuntyurrutu, when the river rises following heavy rains. During this time saltwater crocodiles, echidnas and rock pythons are also actively hunted.

The dry season is coming when the speargrass stalks start to die and turn a reddish colour. This season is known as Wurr wirribem filgarri, and is when people actively hunt for prawns in the river and creeks.

Wurr bengin derripal is a season name that literally translates to “it’s knocked the grass into a bent over position”. It refers to the times of the year when storms push the speargrass over. It is still raining, and is a good time for harvesting magpie goose eggs as there is still a fair amount of water around to support the floating goose nests. This time of the year is known to be good for catfish, but is not yet time for hunting other fish.

Resource collection starts to ramp up with the arrival of the season known as Wirirr marrgu. The dry season is now in full swing; the speargrass is being burnt and black ash is on the ground. Dagum, the fog and dew that are present in the mornings, is seen now. The fog is a good sign to go fishing for black bream, archer fish, mullet, cherabin and prawns.

The Gooniyandi Seasonal Calendar

According to the Gooniyandi language group of the Kimberley region in far north-western Australia, the rain events that arrive in their country from four different directions are generated by four spiritual snakes of different skins or clan groups. The detailed observations of different winds, clouds and storms types in the Gooniyandi seasonal calendar are tied to key resource-harvesting events and are explained via a complex cycle of linked events.

Barndiwiri is the first rain storm of the wet season. It is associated with the Jangala snake and arrives from the north. People know that this storm will make the rivers run.

The flowers of Girndi, the black plum, fall to the ground with the first light rain of the wet season. The fruits grow in the initial wet season rains, and the flickering of fireflies at this time of the year (who share the same name as the plum) are said to “cook” the fruit, making it ripe.

Gooloowa is the rain that falls after the monsoons have finished and as Ngamari (the female cold season) starts. Fish are said to shut their mouths when the Moongoowarla wind starts blowing from the east and the weather cools. This can be a difficult time for fishing.

As the wet season rains finish, the wind changes direction and the Garrawoorda wind blows from the south. The water is high, and this is a good time for catching sawfish. The appearance of red dragonflies at this time also tells you the sawfish are fat. This is in contrast to the hunting time indicated in the Ngan’gi seasonal calendar, and is partly a reflection of the contrasting hydrology of the Daly and Fitzroy river systems.

Wirayi are the boomerang-shaped clouds that can be seen at the end of the very hot weather of Barrangga season. Wirayi clouds warn of a big storm coming, while Manyboo are the white “cotton wool” clouds that originate in the spring country during the middle of Yidirla, the wet season.

Towards the end of the period of mild cold weather known as Girlinggoowa, the “crocodile tree” Bambira flowers, signalling that freshwater crocodiles are laying eggs and it is time to go and collect them. Once the hot season of Barrangga arrives, the flowers fall to the ground, the eggs have hatched and the collection season has finished.

The diversity of indigenous seasonal understanding in northern Australia is driven by many factors, including the diversity of climatic drivers, which dictate to a degree the resulting vegetation and animal communities. However, four factors interconnect within each of the seasonal knowledge systems: a focus on resource use; knowledge of complex ecological indicators and phenology to facilitate resource collection; knowledge of meteorological phenomena; and a strong metaphysical/spiritual component to their understanding.

Phenological knowledge is a significant aspect of many indigenous knowledge systems around the world and is drawing interest from non-indigenous people due to its potential as a new way of monitoring for environmental change. A disassociation or disconnection between previously linked life cycle stages of two species could trigger an early warning of higher level disturbances or changes within an ecosystem, whether they are due to climatic variation or other environmental perturbation.

There is great opportunity for indigenous seasonal knowledge, maintained through continuous local observation of the environment, to be adopted in formalised local monitoring for environmental and climatic change. Further investigation into how indigenous knowledge might play a role in such monitoring and early detection of environment change over longer time scales, or multiple annual cycles, could be of great benefit in the management of Australia’s environment.

Emma Woodward is a researcher with CSIRO Ecosystem Sciences based at the Tropical Ecosystems Research Centre in Darwin.