Best time to dive Perth & Rottnest Island
When is the best time of year to go diving in Perth and surrounding areas?
Most people would imagine that the best time to dive in Perth is summer. Whilst this is a fairly good assumption because it is always warm and the sky is clear, this is not always the case. Being in a “temperate” zone we can enjoy great conditions all year round, albeit at some times of year it may be a bit cooler.
The best time of year in my opinion is autumn. This time of year we have usually nice warm weather and the water temperature is at its warmest coming out of summer. (The water temperature can range from 17 degrees to 26 degrees around Perth and can go as low as 12 degrees in Esperance and rarely over 21 degrees there also.)
The other advantage of diving in autumn is that the sea breezes are less intense so the afternoons aren’t too windy for the trip back to shore after a boat dive or two.
Cooler water usually gives us better visibility and winter gives us a diverse mixture of marine life as this is when we see the biggest changes in water temperature. Warmer water creatures generally migrate and cooler water species begin to turn up in the later months of autumn. Visibility can improve by 10 to 15 metres more in winter than in summer. The only down side of winter is that it generally tends to be colder out of the water than in it and that puts a lot of divers off diving. Solutions to this is no different to what we do in Winter as opposed to summer with clothing… we either layer up (under suits underneath our wetsuits) or we can wear Dry Suits. These are like a wetsuit only they seal around your feet, neck and wrists to prevent water from getting into the suit. This means that you can dive in your tracksuit pants and jumper and stay toasty warm and then when the dive is over, jump out of the suit and you are dry and ready to go for your next adventure!
Adding this to the visibility and often calmer seas without the strong afternoon sea breezes, you are in for a great time diving in winter. (Don’t forget too – the best time to dive for Prawns in the river is also during winter, because the fresh water runoff flushes the prawns out and gives you much more chance of getting a good feed in just a singl
Spring is another favourite time of year for me to go diving. The water is getting warmer and is still clear from winter, the sun is starting to get some warmth to it making it nicer to get changed into wetsuits without getting cold and the skies are clear. Marine species and varieties start to change too. We also see more marine life around spring at Rottnest due to the Demersal fishing bans (15th of October to 15th of December) which allows the bigger fish to reproduce and gives them a chance to increase in numbers. This shows in areas just outside of Marine Sanctuaries which always have a good quantity and diverse range of fish.
This is by far the busiest time of year for dive shops and for diving in general. This is when getting in the water is a relief from the hot days and being able to experience what Western Australia has to offer in ocean adventures is what makes living in WA so awesome!
During summer we get flat calm oceans on the back of light easterly winds which level things off and often give glass like ocean conditions. Visibility improves by 3 to 5 metres on every consecutive day of easterly winds and heading out on boats is amazing!
During summer we generally get to take out pick of all of the sites Rottnest Island has to offer. The only down side to Summer diving in Perth is the Sea Breeze (Fremantle Doctor) which tends to pick up in the afternoons making most “later in the day” trips back to shore a bit wobbly and wet. It’s still all, part of the adventure though and getting back to Fremantle with plenty of time and daylight to be able to enjoy a drink or two and a nice meal by the ocean side is a great way to top of a fantastic day of diving.