Tailor - Fraser Island monitoring
Each year, in late winter and spring, large numbers of anglers gather along the ocean beaches on Fraser Island to fish, mainly for tailor. Fisheries Queensland conducts surveys on Fraser Island during this period to collect biological information for beach-caught species including tailor.
Surveys typically run for five days, with two to three surveys being conducted each year since 1999. Scientists measure approximately 1000 fish per survey, although in years when a survey coincides with great fishing conditions, this can exceed 2500 fish. Scientists also collect large numbers of fish frames (i.e. their skeletons) as these provide additional information to complement the length data.
A mobile field laboratory is set up on the island to allow processing of fish frames soon after they are collected. Scientists record length and sex, and remove otoliths (ear bones) from a sub-sample of the fish frames donated. The otoliths are examined under a microscope to estimate the age of the fish .
The data collected during surveys on Fraser Island are collated with data collected year-round from recreational and commercial fishers at other locations. Collectively, this information allows Fisheries Queensland to assess the sustainability of the tailor stock. Tailor is currently classified as Sustainably Fished .
Monitoring results: size
The majority of tailor caught are between 35 and 50 cm TL. The Fraser Island surveys have shown large fish (e.g. >50 cm) comprise a larger percentage of the catch later in the fishing season (i.e. Survey 3, Figure 2), compared to earlier in the fishing season (i.e. Survey 1, Figure 2).
Monitoring results: Fish age
Scientists can often estimate a fish’s age from its ear bones (Figure 1). Tailor are fast growing and relatively short-lived predators. They reach maturity between 1-2 years of age and can reach a maximum of 13 years of age.
In the 1990s the majority of tailor caught were one or two year old fish (Hoyle et al. 2000). The reliance of the fishery on these very young fish caused great concern about the long-term sustainability of the fishery, resulting in a range of changes to management being made to address that concern (see Table). Over time, the percentage of the catch consisting of older fish (especially three year olds) has increased. This is a positive change in the age structure of the fishery.
The fishery for tailor has had a series of changes to management since the early 1990s (Table). These changes were put in place to protect breeding stock or to lower fishing mortality. It is difficult to determine the benefit of each of these measures in isolation; however, together they are successful in supporting a sustainable fishery for tailor.
|Year||Summary of management changes related to tailor|
|1990||Minimum size limit of 30 cm Total Length (TL) introduced|
|1990||Seasonal closure on Fraser Island in September around Indian Head introduced|
|2001||Commercial net fishing catch limits in NSW began|
|2002||Seasonal closure on Fraser Island expanded to include August and September|
|2002||Possession limit of 20 fish introduced (30 for fishers staying >72 hrs on Fraser Island)|
|2002||Total allowable catch (quota) of 120 tonnes for commercial fishers introduced|
|2003||Commercial fishing restricted on eastern beach of Fraser Island|
|2010||Minimum size limit of 35 cm TL introduced; possession limit of 20 for all fishers|
How old is your fish?
It is possible to estimate the approximate age of a fish from its length. To obtain the best estimate of age, measure the total length of the fish (you can find this length on the horizontal axis of the graph in Figure 4) and determine the estimate of the fish’s age.
Support and assistance
Thank you to the fishers who assist our monitoring efforts by allowing us to measure their fish or by donating their fish frames whilst on Fraser Island or other sampling locations.