Sep 24, 20183 min read

Swimming with the Fishes

Updated: Jul 10

As I'm sure most of you have figured out by now, I'm doing shark research! It's easy to explain to people that we collect data in the field as well as on sharks we have in the lab. The one place people get lost is how they get from the ocean, into our tanks. It's not too difficult of an answer though. We go fishing! Although I do think it should be called sharking since we're fishing for sharks.

The sharks that we bring back to the lab are generally under a meter in length and are our common catsharks. These guys (and gals) are found swimming along the bottom of rocky or sandy sea floors. Our most frequent visitor is the Dark Shyshark which only gets up to 60cm. Our biggest one is the Pyjama catshark which can reach up to 120cm. For most of the ones that we catch, the sharks are fairly docile once we grab them.

One such method of catching sharks is snorkeling. We will put out a bait canister in the middle of our snorkeling area about 20min before we get in the water so that it has time to spread around and attract the sharks. When we get in, it's a game of hide and seek tag. We'll snorkel around trying to find them and once one is spotted, we dive down and attempt to grab it. If we don't catch it on the first try, they normally swim a couple rocks away and settle back down, giving us another shot. Once we have them, they might wriggle around for a second but then become complaisant and often even curl up in a ball making our job easier. We then just swim back to the shore and put it in a bucket to transfer them into the tanks.

On days that we are hoping to catch a lot, we bring out the "shark elevator." It's a converted lobster trap with weights on one side and a buoy on the other and a one way net in the middle. We put it around where the sharks normally hang out so that it's close by for the catch. This allows us to continue to collect sharks without swimming all the way back to shore after every one.

The other methods we use are various forms of fishing. Handlining is a reel of fishing line that we drop into the water over the rocks or at a dock. Rod and Reel is the typical fishing with a (you guessed it) rod and reel. This method generally catches bigger sharks since it reaches greater distances. The third common method we use is long lining which is a long line (makes sense) with a cement block on each side of the line to hold it under the water. There are around 15 hooks on the line about 3 to 5 meters apart. The line gets left in the water for about an hour to an hour and a half and then slowly gets pulled in. These sharks are often on the bigger side so we often take measurements and tag it then let it go. During the hour or two that we're on the boat waiting for the longline, we will also handline to pass the time.

Whatever method we use and however long we get to keep them, each new shark becomes the new favorite. During every release, we'll stand there watching our babies swim off into the deep blue, just hoping we'll catch them again some day.