Last weekend we had boat dives out of Hout Bay, to two of the lesser dived sites (the Sentinel and Die Josie). Maori Bay was very green but we found lovely visibility right up against the mountains.
The water in False Bay is very clean and cold right now. Sadly, the wind for Saturday is at the limit of what I think will be pleasant. Sunday’s wind will be way too strong. Furthermore, the Navy Festival this weekend spells traffic chaos as well as parking issues for boat trailers and tow cars.
These reasons induce me to skip diving over the weekend and plan boat dives for Tuesday, which is a public holiday. The Atlantic will again be cool, flat and clean so we will launch from Hout Bay, nice and early. Text or Whatsapp me if you want to be updated on meeting times and dive sites.
It is certainly going to be the best weekend in a while, as far as diving goes. There has not been too much of that recently! There are light winds and a 3 metre swell, but it is a westerly swell so I don’t think it will affect False Bay too much.
We seem set for a week of pleasant conditions. That rates as a good early Christmas present in my book. On Saturday and Sunday we will launch from Simon’s Town early to finish a few Advanced and Nitrox courses.
On Monday we will do shore dives to continue with Open Water courses, and the rest of the week will be for fun diving. Let me know where you want to go and when you’re free, and I will see if we can make it happen.
Stuck for Christmas presents? Check out our 2015 gift guide. It’s still pretty fresh, but to it I would add Into a Raging Sea, by Andrew Ingram and Tony Weaver, commemorating 50 years of the NSRI. Available at all good bookshops!
Saturday and Sunday: To be confirmed depending on what the wind does!
The day time temperatures are getting to a point where T shorts and shirts are a common sight. Despite the odd off day the sun has been doing good work and the water temperature is nearly 17 degrees in False Bay… In most places. Lest we forget, the south easter also makes itself known again at this time of year, and this weekend is a good example.
It blows hard all day tomorrow and lets up a little for Saturday and a little more for Sunday. It is likely to be last minute call as to whether we head to Hout Bay or False Bay for the some dives. If you want to be on the list for either Saturday or Sunday get in touch and I’ll keep you posted.
Diversnight is next Saturday, 5 November! Charge your torches!
The weather for warm, sunny diving is here – almost! As I’m sure you noticed, we had a day or two of temperatures in the high twenties which is my kind of weather. False Bay has been pleasant this week, with some visibility and not much swell to go with the sunny days. It won’t be quite that warm this weekend but conditions will definitely be worth diving.
We will shore dive at Long Beachon Saturday and launch for boat dives from the Simon’s Town jettyon Sunday. Both boat dives will be to a maximum depth of 18 metres as they will be first boat dives for a few students. Sites will be chosen on the day.
Saturday and Sunday: early launches (around 7 am), location to be confirmed
I am working through some student dives as we enter the final quarter of the year, so am planning launches for both Saturday and Sunday. They will likely be early double tank dives, around 7.00 am, because the wind is forecast to pick up later in the day. The location – Hout Bay or False Bay – will be confirmed tomorrow afternoon when it’s clear which of all the contradictory weather forecasts are accurate! Want to dive? Let me know.
The days are getting longer and the daytime temperatures are slowly creeping upwards… Well, on some days. Saturday looks like a better bet for False Bay with Hout Bay being an option on Sunday. The water colour off Dungeons has improved slightly today.
Tomorrow I am shore diving students at Long Beach at 10.00 am. On Saturday we will do an early False Bay double tank dive at 7.00 am. Let me know if you’d like to get wet.
As part of First Thursdays, you can attend the opening of the Birdlife Oceans of Life photographic exhibition at the South African Museum on the evening of Thursday 6 October. There’s information here (facebook) – this year’s exhibition includes a retrospective of the last few years’ best images.
Diversnight is on Saturday 7 November, so start charging your torches!
A long period 3 metre swell arrives tomorrow, drops on Saturday and then builds again on Sunday. I am planning two launches early on Saturday morning as I have several students to certify. We will meet in the car park at False Bay Yacht Club at 8.00 am. Destination unknown and weather dependent. If you’re keen on a magical mystery tour, drop me an email, text or Whatsapp.
Maritime archaeologist John Gribble is speaking at the auditorium of the South African Astronomical Observatory on Wednesday 17 August, 4.30 for 5.00 pm. His talk is entitled “From Shipwrecks to Hand Axes: An Introduction to South Africa’s Maritime and Underwater Cultural Heritage” and is described as follows:
South Africa’s maritime and underwater cultural heritage is surprisingly diverse and extremely rich. Although shipwrecks are the most obvious elements of this rich heritage resource, there are a range of pre-colonial maritime heritage resources that are less well known. This talk will introduce South Africa’s maritime and underwater cultural heritage, highlight the archaeological importance of this resource, and touch on a few examples of interesting, local historical wrecks.
There is no need to book, the event is free to the public.
Staying with our informal theme of the last few weeks’ (admittedly sporadic) posts, let’s look at a recent article from the New York Times Magazine. Not solely focused on marine animal studies, the article explains how technology has enabled even the general public to directly observe and learn about the migrations of birds, sharks and other animals. The utility of this kind of information is obvious:
By discovering the precise routes animals take during migration, scientists can assess the threats they face, like environments altered by habitat loss and overhunting.
The article’s author is brilliant nature writer Helen MacDonald, who wrote H is for Hawk, and she goes on to muse about the meaning of the relatively few individually tagged and named animals which become icons of their species as they appear to transverse a simplified, borderless planet in solitude. (The OCEARCH sharks on their satellite map refer!) It is easy to lose sight of the rigours of the environments they move through, but easy to become invested in the future of particular individuals.
Did you pick up the July edition of National Geographic to read about great white sharks, or read the article online? (Pro tip: you should.)
The article’s author, science writer Erik Vance, contributes to a blog that I follow called The Last Word on Nothing. I was delighted to read a follow-up he posted to his National Geographic feature, explaining how scientists count sharks. At the heart of the method is a beautiful piece of statistics (a model) that allows scientists to draw conclusions about the size of a population – some of whom are tagged or marked – based on only a sample of the individuals, and what proportion of those sampled individuals is tagged.
Why is it important to know how many great white sharks (or cowsharks, or whale sharks, or or or…) there are? The most obvious answer relates to conservation: if we have a baseline population estimate, we can then determine whether it is increasing or decreasing over time. What is the status of the population? Are these animals endangered, or flourishing? Are conservation measures necessary? Are they effective?
Go and read about counting sharks here. An important thing to pay attention to when you are reading any scientific model is what the underlying assumptions are, because they will show you the circumstances under which the model will fail.