HabCam Part II—A Closer Look at Our Science and Technology
A skate spotted alongside scallops on the seafloor. Photo Credit: HabCam Group.
A close-up of the HabCam before being submersed in the water. Photo Credit: HabCam Group.
July 11, 2012
Let’s take a closer look at the Habitat Camera Mapping System (HabCam) to see what exactly it can accomplish and divulge about the seafloor.
More Images, Better Estimates
Snapping up to 500,000 images of the seafloor per day, the HabCam takes roughly six images per second. And what develops is significant.
“The HabCam leads to a better estimate of scallops, which then significantly influences the total allowable catch that is set,” NOAA fishery biologist Laura Oremland said. Fishery Management Councils set the total allowable catch which dictates how much biomass—or the number of scallops in an area converted to weight—fishermen are allowed to bring in, and it’s an extremely important number.
Ultimately, more accurate estimates lead to more accurate catch estimates—which lend better assessments for fishery management. If the biomass is off, then the catch limits are off, and this could mean a huge chunk of revenue is not available to the fishing community.
Getting a Better Look at the Ocean Floor
HabCam images are far more than just a surveying tool. For scientists, they’re a window into species interaction and habitat characterization. They shed light on the behavior of scallop predators like sea stars and whelk, and symbiotic scallop relationships, like red hake.
While scientists recognize that juvenile red hake find shelter inside the scallop’s shell, HabCam photographs reveal a lesser known fact: the adult red hake are often found in the vicinity of a sea scallop, and are sometimes observed to curl around a scallop. While there is a very limited commercial fishery for red hake, commonly marketed as “ling,” the main management implication of the hake’s association with scallops is that the increase in scallops gives hake more favorable habitat and probably better survival, especially during their juvenile stages.
The camera has also been useful in counting flounder, hake, and skate species, which can be difficult to assess by other means. With this new seafloor coverage, scientists can learn more about the scallop population and much more about what’s going on at the bottom of the ocean.
“Not only does HabCam tremendously increase the spatial range of coverage, because data is collected in continuous strips, it gives us an opportunity to understand how deep sea organisms are distributed at all scales,” said NOAA Operations Research Analyst Deborah Hart, Ph.D. Using the dredge and HabCam methods in tandem increases both survey efficiency and the accuracy of estimated scallop biomass. Unlike a dredge, which only captures some of the scallops it travels over, a camera can reveal all the scallops.
“As with any sampling system, HabCam measurement errors do occur,” said Woods Hole Oceanographic Institute scientist Scott Gallager. “But unlike other approaches, the HabCam is well calibrated so the source and magnitude of errors are known and minimized.”
HabCam gives scientists a different, in-depth look at the ocean floor. Although HabCam does not replace the dredge, which remains essential for specimen collection, together they provide the best available science to inform fisheries management and aid in NOAA’s fight to end overfishing. That’s one powerful picture for the future.
For more information about this technology, explore HabCam Part I: An Innovative (or A Better) Way to Survey Scallop Habitat.