Monday, November 23, 2009

The Missing Pyramid...

Total missing GPS units from Heppell Lab:

Total number of search dives to recover location of pyramid:

Looking for a small pile of cinderblocks in cold water in a wetsuit on the Oregon coast in the dead of winter with fellow Heppell Lab members:

Shivonne, Scott, Stephanie, Luke, Brittany and Heather. Photo by Ali Dauble.

One of my artificial reef structures, the elusive fifth pyramid (of six), has been "missing" for several months now. Since the pyramid is about 1800 lbs of cinderblocks and mortar inside a large steel frame, it has not moved to another estuary, contrary to popular lab opinion. A recreational boater probably ran over the mooring buoy, so it is not currently marked (aka, "missing").

The artificial structures were constructed and deployed specifically for the purpose of developing an estuarine juvenile rockfish recruitment index, one part of my master's thesis. The structures were originally deployed in February 2008 and have remained in the murky waters of Yaquina Bay on the central Oregon coast ever since. Dive surveys on the structures for the last two years demonstrate that they were extremely successful in recruiting newly settled juvenile rockfish in both 2008 and 200
9, in addition to many other fish and invertebrate species, and will provide us with more information regarding juvenile rockfish settlement rates within an estuary on the Oregon coast.

Does anyone remember "We found the sixth pyramid!"? Stephanie and Heather. Photo by Ali Dauble.

The photos in this post are from one of the search dives in late October where I had a large crew of divers from the Heppell Lab come out with me (and actually remembered my camera during all of the planning). Unfortunately, these search dives were all unsuccessful in locating the fifth pyramid (see photo above). As of now, the current plan is to do some slow trawling with the lab boat, the Marine Team whaler, instead of search dives, continuing sometime in December. This will allow us to cover a lot more ground during slack tide and not kill me organizing more large dive crews.

A special thank you to all who came out to help dive for these search dives and thanks for your volunteer dives over the last two years!

The dive crew on a (surprisingly) beautiful day in Yaquina Bay. Scott, Heather, Shivonne, Ali, Brittany, and Stephanie. Photo by Ali Dauble.

1 comment:

  1. Great photos Ali! I wonder if we'll ever find the pyramid!