mapping the house reef

A few days ago I went out with Oksin to do some more mapping of the house reef, and while I was fussing around, he took some candid shots!
Mapping is pretty straightforward and easy to do. First, you take a finger spool and mark it out (it helps if the line is dry enough to to mark with a pen.. this part takes a little bit of pre-planning) I marked my reel in ten foot increments, with the first 20 feet having one foot increment markings as well.
The next part is easier to do with two people, but still feasible by yourself. Have one person stay stationary at one object and have the other swim with the line in hand to the next object. That person can take a compass bearing from the first object to the second, while the second person counts the tick marks on the spool as they reel it back up. For objects that are farther apart, or even just past visibility range, its best if the stationary person keeps the reel, to avoid tangling the line. If the object is farther away than you can see, the swimmer can give a couple of tugs on the line to let the other person know when to start reeling in. For these situations its beneficial to have a preliminary idea of the layout so you have a basic idea where to find everything. :)
As you go along mapping, take a slate and sketch out each object, writing down the compass bearing, length of reel used and a line following the course of the reel. It also helps to take note of the depth at each object as well.
Then, when you get back onto dry land, redraw your underwater map on a piece of paper with a pencil, ruler, and your compass. To make things easier, orient the paper to follow the course of the map ( for example, the house reef generally runs at 30 degrees parallel to land, so I oriented the paper to 30 degrees and drew the map around that).

There you have it, a finished map!