By Emily Weekes
While fish-landing statistics in Queensland have been collected since the 1940s, they only provide an indication of what was caught and processed and do not include many of the other forms of data available such as fishing reports in newspapers or magazines.
The introduction of individual logbooks in 1988 has provided more detailed information in recent years about the where, when and how of harvests, but longer-term data is seen as critical to the success of future fisheries management.
Details of past catch rates, average fish size and changes in the marine environment can be used to improve future stock-assessment models.
Longer-term perspectives can help reduce uncertainty when projecting historical catch levels and historical fishery trends can provide valuable information to help improve management strategies.
Ruth Thurstan and Sarah Buckley at the University of Queensland have embarked on the challenge to piece together a more detailed picture of the state’s fisheries history.
To do so, they are interviewing experienced fishers, both young and old, and scouring old newspapers, archival records from the Queensland Fish Board and local fishing communities, focusing on two iconic Queensland fish species: Snapper (Pagrus auratus) and Spanish Mackerel (Scomberomorus commerson).
“We’re hoping to provide insights from the past and a context for the trends we’re seeing today,” Ruth Thurstan says.
“If we can also produce good-quality, high-resolution data, then we might be able to help inform stock-assessment processes by sharing our research with managers and fishing communities.”
A 2009 stock assessment declared Snapper to be ‘overfished’, making it a perfect candidate for the project. The species had been popular for decades, much longer than the existence of landing statistics. Offshore Snapper fisheries records date back to the 1870s when it became a popular recreational pursuit.
Spanish Mackerel also has a long history as a popular target for fishers along the east coast of Queensland. This transient species spawns in the north, near Townsville, and migrates south to the New South Wales border. While other species are also worthy of attention, focusing specifically on two species became essential to make the project manageable.
Landing statistics gathered by the Queensland Fish Board (replaced by the Queensland Fish Marketing Authority) offer insight into the numbers caught and processed, but they rarely tell the whole story.
Archival sources, by comparison, allow researchers a window into 19th and 20th-century fishing practices, while interviews with different fishers help flesh out observations from the more recent past.
Assisted by the FRDC, Ruth Thurstan and Sarah Buckley have travelled across Queensland interviewing current and retired commercial, recreational and charter fishers. The breadth of interviews has evolved over the past year, as fishers suggest new leads for interviewees and locations.
At the same time, the researchers are sifting through microfiche reels of archival material, from newspaper extracts and articles to fishing club records and even personal records.
Several online digitised sources have proven valuable, as have local history archives, offering information not as widely known.
Ruth Thurstan says since the late 1990s archival sources have been recognised as increasingly valuable in generating historical trends, largely due to a surge of interest in the marine environment and a dearth of available data.
The difficulty in placing contemporary trends into perspective, when faced with a lack of long-term knowledge, has led researchers to investigate a wider variety of sources.
Similarly, fisher recollections have proven valuable in a growing number of studies, she says. While not yet a common approach, interviews have been used in the US and the UK in the field of historical ecology.
“They’re all incredibly valuable pieces of information. We thought that if we used as many data sources as possible, then it would be a good way to gather this information and get people involved.”
Ruth Thurstan says archival material does raise certain challenges.
Researchers must be aware of bias when interpreting each source. Even the reporting of fish catches in newspapers, a seemingly reliable historical source, can reveal a level of uncertainty when studied more deeply.
“Are they reporting average catches or are they actually representative of what was being caught or perhaps even an overestimation?” Ruth Thurstan asks. “I don’t doubt that the numbers of fish they said they were catching are correct, but it might be that they weren’t reporting the poor catches, only the good catches.”
One strategy to mitigate the murky influence of bias is to use as many different data sources as possible and comb for trends across a large and varied sample size. The challenge then is to find a way to link these together and form a timeline of the fisheries.
Some archival sources have already revealed riches. Extracts of Snapper catches from the 1870s record landings of Snapper by the hour, by the fisher or by the boat.
To date, more than 300 individual sources have provided catch rates for a particular period and location – up to seven decades prior to the start of landing statistics that show only overall landings.
The project aims to sample geographically as broadly as possible and to speak to as many fishers as time allows. The study of Spanish Mackerel spans as far north as Cairns and encompasses the major population areas south to the NSW border.
The Snapper research is focused from Brisbane to Gladstone, where significant catches have been known to occur. The study could potentially continue south into NSW as these fish are part of the same Snapper population.
This would provide a picture of the wider trends along the east coast; Snapper are at the northern-most point of their range in Queensland waters.
As the project unfolds, other factors may be considered, such as the impact of development along the coast and changing environmental conditions.
Ruth Thurstan says the response to the project, to date, has been positive. Fishers have been happy to participate and have understood the need for information.
The researchers plan to share their findings with the participating communities next year. Once the data is released and has been analysed, discussions can begin about how to incorporate this into fisheries management.
“We’re not looking for anything in particular, because we don’t really know what’s there, until we find it,” Ruth Thurstan says. “When you don’t know what you’re going to find, that can be quite exciting.”
News story on Spanish Mackerel from a 1982 edition of Fishing News.
Ruth Thurstan trawling through newspapers in the State Library of Queensland. (Photo: Sarah Buckley)
FRDC Research Code: 2013-018
Ruth Thurstan, 0450 586 263