31 March 2016
Researchers have analysed a year’s worth of video imagery from the popular Entrance Point boat ramp, adjacent to the Broome Fishing Club, to explore the factors affecting the launching of recreational boats, as part of a broader WAMSI study looking at Human Use in the Kimberley.
In total, 6057 recreational boat launches were recorded by the Western Australian Department of Fisheries camera at Entrance Point during the 12 month study. The figure shows that, despite the town of Broome only having a relatively small resident population of about 13,000 people, boating is a popular activity.
To put it into context, the total at Entrance Point is equivalent to about 22 per cent of the total number of launches per year at Hillarys boat ramp which is one of the busiest in the Perth Metropolitan area.
On a seasonal basis, 60 per cent of all boat launches at Entrance Point occurred during the dry, winter season (May to October) and on a monthly basis, July and August had the highest numbers of boat launches (totals of 825 and 882, respectively).
The average number of boat launches per day generally showed an increase on weekends although from July to September there were increased numbers of launches on weekdays as well.
Throughout the year, the peak in boat launching took place in the morning between 6 am and 10 am.
|Mean hourly boat launch rate per month at Entrance Point boat ramp, Broome, from November 2012 to October 2013.|
“The results support the original hypothesis that there would be an increase in boat launches during the dry, winter season when there are known to be more visitors (especially ‘grey nomads’) to Broome,” project leader Murdoch University’s Professor Lynnath Beckley said. “However, consistent launching of boats during the wet, summer season (40 per cent of all launches) clearly indicates the importance the residents of Broome place on recreational boating.”
The boat launching data were also explored relative to environmental factors like air and sea temperature, wind speed and direction, rainfall, barometric pressure and tides as well as time of day, day type (weekday, weekend or public holiday) and school holidays.
Time series analyses of the hourly launch data showed that day type, time of day, school holidays and tidal height were significant predictors that together described the most variation in the launches on a daily cycle. For the weekly cycle, only day type and wind speed were significant predictors.
“The Entrance Point boat ramp is only one of several sites from where recreational boats are launched in Broome and this may have some bearing on the patterns found,” Professor Beckley said. “For example, during the winter mornings when there can be strong easterly winds, many boats are launched instead from the southern end of Cable Beach which is more protected from these winds.”
|Entrance Point boat ramp at Broome in peak season (Lynnath Beckley)|
The $30 million Kimberley Marine Research Program is funded through major investment supported by $12 million from the Western Australian government's Kimberley Science and Conservation Strategy co-invested by the WAMSI partners and supported by the Traditional Owners of the Kimberley.