Laidig et al Reactions of fishes to a manned submersible and a remotely operated vehicle 
55 
122’0’0-W 
Figure t 
Map of the area inside and outside of 3 marine protected areas (MPAs) 
off central California that was surveyed in 2007 for our study of the reac- 
tions of fishes to the manned Delta submersible and a remotely operated 
vehicle (ROV). Polygon shapes outline the MPAs, and triangles and circles 
indicate dive locations for the submersible and ROV. Bathymetry is in 
given meters. 
Materials and methods 
Fish surveys were conducted off central 
California (Fig. 1) inside and outside of 3 
recently created marine protected areas 
(MPAs) — Point Lobos, Portuguese Ledge, 
and Soquel Canyon — with the 2-person 
Delta submersible (Delta Oceanographies, 
Torrance, CA) and a Phantom DS4 1 ROV 
(Deep Ocean Engineering, San Jose, CA). 
The manned submersible surveys occurred 
during the period of 20 September-5 No- 
vember, 2007, at depths of 30-365 m, and 
the ROV surveys were conducted during 
the period of 18-23 November, 2007, at 
depths of 71-408 m. All surveys were con- 
ducted during daylight hours from 0800 
to 1700. Each submersible dive comprised 
2-6 transects, each of a 10-min duration. 
The ROV dives were 1-3 h in duration. 
The ROV surveys were conducted along 
the same path of only a subset of the sub- 
mersible transects; in other words, not all 
submersible transects were paired with an 
ROV dive (Fig. 1). 
The Delta submersible (Fig. 2A) was 
launched from the FV Velero IV and op- 
erated by experienced pilots from Delta 
Oceanographies. An experienced scientific 
observer accompanied the pilot inside 
the untethered submersible. This yellow- 
orange submersible was 1.8 m tall, 4.6 m 
long, and from 0.4 m wide at its forward- 
most part to 1.1 m wide at mid-vehicle. 
The submersible was equipped with 2 vid- 
eo cameras: 1) a forward-facing, low-light, 
wide-angle, monochrome camera (Super 
SeaCam 5000, DeepSea Power and Light, 
San Diego, CA), and 2) a starboard-mount- 
ed, custom-built, color zoom camera with 
400 iines of resolution and an illumina- 
tion range of 2-100,000 lux (Yoklavich and 
O’Connell, 2008). The position of the Delta 
submersible was tracked from the support 
vessel with WinFrog integrated navigation software 
(Fugro Pelagos, San Diego, CA) and an ORE Track- 
point-II ultra-short baseline (USBL) acoustic system 
(EdgeTech, West Wareham, MA). The distance traveled 
was estimated with a ring laser gyro and Doppler ve- 
locity log attached to the outside of the submersible. 
A single 24-volt propeller provided thrust. During sur- 
veys, the Delta traveled at an average speed of 0.5 m/s, 
~1 m above the seafloor, following a directional heading 
given to the pilot by scientists aboard the support ves- 
sel. The submersible was equipped with ten 150-watt 
1 Mention of trade names or commercial companies is for 
identification purposes only and does not imply endorsement 
by the National Marine Fisheries Service, NOAA. 
halogen bulbs; only 3 of the starboard lights and 1 of 
the front-mounted forward-facing lights were used to 
illuminate the transect area. 
We also used an unmanned Phantom DS4 ROV 
launched from and tethered to the NOAA Ship Da- 
vid Starr Jordan and operated by experienced pilots 
from the National Marine Fisheries Service, South- 
west Fisheries Science Center, in La Jolla, California 
(Fig. 2B). The ROV had a yellow body and black frame 
and was 1 m tall, 2 m long, and 1.4 m wide. The ROV 
was equipped with a forward-facing, color video cam- 
era (Sony FCB-IX47C, Sony Corp., Tokyo, Japan) with 
470 lines of horizontal resolution and an 18x optical 
zoom. Like the position of the submersible, the position 
of the ROV was tracked with WinFrog software and 
