ADP Journal: Beach Survey 9/2/06

Filed under: — Anastasia @ 3:32 pm

In case 10 weekends of wall-to-wall ADP wasn’t enough, we were all given a project for September: on our own time, divide into groups and do a beach survey. This shall entail:

  • Getting a group together on a free weekend. This is quite a task in and of itself, logistics-wise.
  • Selecting a beach everyone is interested in.
  • Writing up everything there is to know about said beach
  • Diving at the beach, AND
  • Conducting a formal survey of a roughly 200′ by 50′ patch of underwater, using lines, buoys, and slates to record depths, substrates and marine life on a grid.

I joined up with a bunch of folks who decided Old Marineland, on the south side of Palos Verdes, would be a fun dive. None of us had actually dived it before, but OML is a famous dive spot among locals; it tends to have nice conditions and really cool stuff to see, if you can manage to get in the water. There’s a bit of a hike down (and hence, back up), and the most popular entry is off some rather tricky boulders. A slightly easier entry is offered at a cobblestone beach, out from which there’s mostly sand.

Cobblestone beach, as seen from the walk down – that’s us with our float:

I remember this dive site as the location of one of my first beach dive attempts with the Sole Searchers, where I was roundly scared away by the surf pounding on the slimy boulders (at entry #1) and the surf tossing around all the loose rocks (at entry #2). Jeff and I huffed all the way down and back up without actually diving.

This time, we had better conditions. Eight of us gathered in the parking lot above OML, and were ready to hit the water by 10am or so (downright late in the morning by ADP standards). We spent a bit of time coordinating logistics of the survey in the parking lot: how to stay in formation, how to signal each other when we were done taking readings, whether or not to lug the floats along with us (we did), etc. Then it was down the once-scary hill, which didn’t seem as hard as I remembered it, and onto the cobblestone beach (not wanting to wrangle the floats over the already-tricky boulders), which didn’t look as scary as I remembered it. So far, so good.

And it stayed that way. Meca and I were first into the water with a float (with Mike’s help ‘tossing’ it out to us), which we dropped towards the west end of the cove. Then we hit the bottom and started unspooling line in the direction of the reef (west towards the boulders). Even with my fancy new PVC line spool, assembled the night before, working with lightweight line underwater was a bit of a bitch. We persevered, and laid out 100′ of line over… sand. Boring, boring sand. We finally hit a bit of rock at the end, where the reef appeared to just be starting.

Back on the surface, we were joined by Sam and David sporting float #2, which they anchored at the end of our line. We decided instead of doing either side of a single line, we’d just go straight down the middle of one long line, and hopefully catch some actual topography. Sam and David dropped down with their own 100′ marked line and laid it out over a slightly more interesting section of reef than the first line.

By this time, the remaining two buddy teams had joined us at float #1. We broke into groups of 4, each on one side of the line, and headed out to survey the area.

It’s incredibly easy to do this on land. Put a line down on the grass. Line up perpendicular to the line, everyone arms’ length apart. Take 2 steps forward. Write down what you see. 2 more steps. Repeat. Etc.

It’s a bit nastier underwater, because of surge pushing you back and forth, so every 5 feet in each direction becomes more like “5 feet plus or minus another 5 feet.” Additionally, keeping even 4 divers in a straight line is – well – damn near impossible. We didn’t use a buddy line because we thought there would be kelp (there wasn’t). Passing the “stop, go” signals back and forth was also a little tricky due to difficulties getting each other’s attention, so everyone wound up with a slightly different number of readings.

Our site survey area, on a Google Maps pic of OML:

Still, I had a really fun dive, even just checking out the “boring” side of Old Marineland. We saw plenty of fish, including a big school of jack mackerel and a rainbow seaperch (my first). Spanish shawls, sea hares, keyhole limpets and chestnut cowries all made appearances, as did a few soles in the sand. Mike spotted a batray in the shallows on his way out. So, despite our less-than-scientific underwater survey, we all had a good time – and learned a few things for the next time we try a site survey.

1 Comment

  1. Wow, Anna … good for you! The entry alone looks like a problem! Congratulations!!!

    Comment by Kathy Brantley — 9/12/2006 @ 8:08 am

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