Horn shark Genetics Project 8/8/14-8/12/14

Location: Laguna Beach, California (Crescent bay, Shaw's Cove, Divers Cove, Heisler Park)

By Norbert Lee

     Heterodontus francisci, commonly known as the horn shark is a species of bullhead shark found along the coast of Southern California. They play a key role in the ecology of the kelp forsest ecosystem because of they are one of few species that help preserve the kelp forest from becoming urchin barrens. Evolution has made the hornshark the perfect predators against invertebrates with shells in a couple of ways. First, bullhead sharks have the largest bite force to body ratio of any shark. In addition to the powerful bite, the second ecolutionalry feature of the horn shark is the molar like teeth that is used to grind up shells. With these two powerful weapons combined, the sea urchins that decimate the beautiful kelp forests are easy prey for horn sharks. One way we can see if  horn sharks incorporates urchins in their diet is by looking into the mouth or the horns at the dorsal fin. The teeth or horn of the shark would have a purple or maroon color from the dye of the sea urchins (See picture).

     Now let’s talk about the horn shark habitats and behavior. In order have success in spotting horn sharks, one must be able to understand the best habitat and behavioral patterns of the sharks as well develop a keen eye for spotting prime locations.  The sharks are usually found in shallow waters less than 30 ft in crevices that might have some spiny lobsters or at the base of kelp plants with thick fronds covering the rock. Aside from the habitat horn sharks have high site fidelity, which means they generally do not disperse too far. In fact studies have shown that horn sharks can be found 100 yards from the location that they were tagged. The nice thing about horn sharks that makes it easy to find is the fact that they are mostly nocturnal. Horn sharks typically hunt at night and rest in their hiding spots during the daytime. As a researcher, this made the project eaiser since we did not have to chance after an active swimmer.

     Now that we understand a bit more about horn shark’s let’s dig into the horn shark diving project. I met Sean Canfield, a graduate student from the University of Hawaii at Manoa on the night of the 8th and he explained to me what I can expect from the 4 days of diving. Measuring and clipping fins were easy enough to understand but how to wrangle the sharks was another thing. Sean showed me his bite marks from the horn sharks and explained that they have one of the strongest bite forces for their size compared to other sharks. I was excited and a bit nervous about wrangling the sharks.
 We started the trip of by setting up camp at Caspers Wilderness Park which was not too far from Laguna Beach. We broke the ice with each other and he explained to me the main question of the project. He wanted to create a genetic map of the shark populations around the Southern California coast versus the populations from Catalina Island since there was such a huge distance from the mainland. From this map he hopes to understand the how much genetic differences are there between the populations from the island versus the mainland. This would help us understand if the horn sharks are slowly diverging into a different species from isolation or not.

     It was exciting to ride the surgy and shallow waters of Laguna and wrangling the sharks was fun! (Don't attempt this unless you have a scientific license from the department of fish and game!) The trick was to grab them by the tail and gently wiggle them out of their crevice. The sharks that were bigger 60 cm+ would put up a bigger fight but the small ones were the ones we had to be cautious about. The big sharks could not turn wide enough to bite us, but the little ones can. The little sharks had the sharper teeth and getting bit by one was not that painful but a surprising to say the least. Once we controlled and measure the shark, I clipped a thumbnail size portion of the dorsal fin (which is not too important for their survival) and stored them in tubes. Our quota was 30 but we got 29 since it was actually quite difficult to find them at a certain point.

     Conducting the series of beach dives was fun but safety was the number one concern. Even though we had a deadline and these were a series of working dives, we had to cancel a couple of dives since the conditions were rough to exit and enter. Hopefully you guys will find some horn sharks of your own. There are a lot in the southern Channel Islands of California for everyone to explore! Be safe and keep diving!

OSDT Full Face Mask Demo and Training Day

We will be holding two sessions on August 14 for divers to try out the new Ocean Reef full face mask and underwater communication system

              
Norman S. Johnson pool in Arcadia (find directions at www.oceansafariscuba.com)
Thursday August 14

First session will be from 7:00-8:00pm

Second session from 8:00-9:00pm


We will provide tanks, weights, full face mask and underwater communication system, please bring your skin diving equipment as well as BC, Regulator

Limited to 6 people per session, so call us to sign up ASAP
Cost: $25

 
See you there!

Cee Ray Cabin Sketch by Erica Yeung

Big Sur Trip

Big Sur, California, has got to be one of the most beautiful places in California. Maybe even the whole US. Tourists from around the world flock to this gorgeous gem to see its clear turquoise waters, with majestic rugged coastline, surrounded by tall luscious trees. I first fell in love with this place during my sophomore year of high school (2007) on a school trip. I didn’t even know that such tropical looking waters existed in temperate oceans.

Photo: Haruka Ito, 2007. No color adjustments, no filter. It’s the real thing taken by a little point and shoot I had at the time. Isn’t it beautiful?

 

 When I saw the trip listed on the OSDT 2014 calendar, I couldn’t be more excited. I wanted to be the first one signed up! Who wouldn’t want to dive in that stunning place?

The first day of the trip, we toured another beautiful city in California, Santa Barbara. We visited the Santa Barbara Maritime Museum, where we got a special private tour by Gabriel’s professor from UC Santa Barbara. This museum houses the spectacular lens from the Point Conception lighthouse, hand crafted in the 1800s. A lens like that, built with numerous precise, handmade glass pieces, can no longer be made, even with modern technology. And the modern replacement cannot shine as bright as that one. The museum is filled with history, not only of the lighthouse, but also the history of how Santa Barbara is the birthplace of commercial diving. The exhibit also highlighted surfing, submarines, rowing, and shipwrecks, so pretty much anyone who loves the ocean will enjoy this museum.

After eating at a harbor side restaurant, which used to be Gabriel’s favorite places to treat himself after long study sessions, we headed to Morro Bay where the boat was docked. The boat is nicer than all the usual local boats we charter! It is the biggest boat, and the galley is so wide that no one has to worry about bumping into each other while walking through. We had a small group, so people had a whole table to themselves! There were very nice large shower rooms, not the usual cramped shower with a toilet taking up most of the space. The single bunks were the size of the usual double bunks. The back deck was so large that there was room to leave gear bags right there! They had dryers, freezers, and refrigerators for the guests to use. The food was amazing and probably the freshest meals I’ve ever had on a California dive boat. So should this be considered a local trip or an overseas trip? Well, I think the feel of it is very much like our local trips, but aboard a nice, huge boat with great food and awesome crew (kind of like a small-scale overseas liveaboard). I don’t think our California diving boats can get much better than aboard the Vision.

The dive sites were top notch. We went to pinnacles, underwater caves and canyons, and other hard-to-get-to spots. One of the highlights was swimming through Thomas’s Cave, which is a huge underwater cave with three entrances. After swimming out of the cave, I entered a spectacular little cove, where the light was shimmering through the water to the eelgrass and seaweed bed. My other favorite dive involved finding little pieces of real jade at Jade Cove, where I got a handful of jade that can be easily turned into nice jewelry pieces.

The Big Sur dives are definitely for advanced dive sites, with plenty of surge, swells, and currents (side current, down current, and currents going all directions). This means that life was abundant and the underwater scene was in full action. The reefs were teeming with life, including white plumose anemone, huge lingcod everywhere, nudibranchs I had never seen before, and purple hydrocorals. Since the water is colder, we saw many things that you can only see at deeper depths in the Channel Islands. There were vermillion and lingcod at fairly shallow depths, around 40 feet or less. This area is also unique, because there are two types of kelp in the kelp forest. From Southern California through the Channel Islands, you only see giant kelp. Giant kelp likes the warmer waters, so they’re not found in the colder Northern waters. From Alaska to Central California, you see lots of bull whip kelp that likes the cold waters. Big Sur is unique in that both types of kelp thrive in the same location. This variety of kelp creates a forest that can house a greater diversity of marine creatures. Things that can only live up north and others that can only live in the south meet and live together in unison. Another interesting marine life observation I made were the number of bat stars that scatter the sea floor in Big Sur. You might see some bat stars at Santa Cruz Island, but they are not the dominant sea star species in the Channel Islands. Also, if you are tired of seeing so many sea urchins on the local trips, Big Sur’s lack of sea urchins overtaking the landscape might soothe your eyes. (The sea otters keep the urchin population in check.) Since the Vision is the only dive boat that operates in the area, and only for two weeks out of the year, you can bet that not many people have a chance to dive in these hard-to-access pinnacles and dive sites.

Aside from diving, you can’t help but stare at the beautiful coastline. We passed by one the most photographed bridge one the West Coast (due to the beautiful design and location that makes it easy to photograph from land). This bridge, the Bixby Creek Bridge, is also the tallest single-span concrete bridges in the world. We also visited McWay Falls in Julia Pfeiffer Burns State Park. This waterfall is the tallest freshwater waterfall (84 feet) that cascades straight into the ocean on the Pacific coast. Hundreds of tourists visit the waterfall, but since there is no beach access allowed, they go on a paved walkway and view the waterfall from high above the falls and far away enough to take in the whole scenery with the turquoise cove. Unlike those tourists, the Vision went straight into the cove, and saw the waterfall up close. I’ve seen the waterfall from the far away viewpoint. To see the waterfall from sea level was one of the most memorable and special moments of the trip.

There’s just so much to do on this trip, from touring Santa Barbara, sightseeing, diving, and simply enjoying the cruise. They also have kayaks on board, if just looking at the coastline isn’t good enough. What an extraordinary trip! You’d better not miss the next opportunity to go dive at this special gem in California, aboard the most comfortable local dive boat, the Vision.

 

Photo: Haruka Ito, 2012. View of McWay falls that tourists see

 

Photo: Haruka Ito, 2014. View of McWay falls aboard the Vision

 

Dive Blog May 4, 2014 Anacapa Island

Explorer Cabin Sketch by Erica Yeung

Dive Blog May 4, 2014 Anacapa Island

Today’s dive trip to Anacapa Island on the Explorer included new personal records, challenging sites, rescue practice, and as usual, a wonderful experience with divers, crew, and dive-sites alike!

The first dive of the day holds my current deepest dive! 115 feet! At first, I was nervous about the depth, on top of the low visibility and current. But when I found myself comfortable at 85 feet, my anxiety subsided. I was excited to see the plane wreck; unfortunately, the anchor was placed too far to safely reach the wreck. Even though I was a little disappointed, I was still thrilled to have dove so deep without any complications. The excitement didn’t end there; I practiced important rescue skills after.

When we got to the next site, Fish Camp, Luis helped refine our rescue towing skills. It was a nice chance to do some surface swimming and practice my kicks. I noticed that my kicks were too small and frequent, so I ended up wasting energy that I could have used to tow my buddy back to the boat. After successfully saving our victims, we had time to practice our pike dives.

The group didn’t seem to have a problem going under. One person (Ian) was even able to get sand from 25 feet deep. I on the other hand, could barely break the surface. I felt like a Margikarp helplessly splashing around. Thankfully, Luis told me that I needed to bend my top half of my body straight down , lift my legs, then kick. I was able to go down, but still had trouble going deeper than 5 feet. Again, Luis helped my techniques. Since we had to return to the boat after, I didn’t get the chance to practice again. However, I was able to practice another skill during the next dive.

At the same site, we enjoyed the vibrant environment while looking for a shallow area to practice our E.S.A. (Emergency Swimming Ascent). This skill was rather easy to carry out; however, I was shocked to have forgotten how to put on my weight belt while in the water! A basic skill that I seldom used needed to be refreshed.

For our last dive, our group faced the most challenging conditions of the day: surge, current, and low visibility. Also, we briefly discussed how to pull unconscious people out of the water. I need to work on my control because I kept hitting/crashing into other divers or rock formations. I also need to build up my stamina because the current pushed us back and our group had to swim for a long time until we returned to the boat.

Overall, this trip showed me that even though I felt okay with my diving, I have lots of room for improvement.  I had lots of fun talking, eating, diving, and sleeping. I am looking forward to more fun diving and skill refining in the near future! Happy diving!

Written by Kristiana Rendon

Illustration by Erica Yeung