This time of year offers the chance to provide a romanticized explanation of autumn on the central coast. I could explain how here at Moss Landing the weather is turning colder, the leaves are changing color, and the storm clouds bring a scented promise of the rains to come. However, we have more important things to discuss: Halloween!
This past weekend was Moss Landing Marine Labs’ annual Halloween Party. Everyone came in costumes and as part of the tradition, each lab or group brought their pumpkin to be judged by the student body in the pumpkin carving contest. Though officially there was only one winner, I think everyone did a great job. What do you think?
Halloween, however isn’t just about carving pumpkins, it also calls for sweet treats and telling tales of the unusual and scary! Ghosts, ghouls, and goblins may be the usual topic of conversation when talking about things that go bump in the night, but my favorite scary creatures to discuss are those truly unusual, and of course, found in the ocean!
One of my favorite “scary” species is the Goblin Shark. Though it is no threat to humans, as it lives very deep, those jaws are a bit spooky!
Another favorite spooky creature of mine is a Bone Worm. These worms feed on skeletons of dead whales! How’s that for an evolutionary adaption?
And last, but certainly not least is the Blobfish. While in water the blobfish has a fairly normal appearance, but out of water – due to low tissue density – its appearance is a bit unusual!
Fellow grad student Catarina Pien and I were lucky enough to visit to the California Academy of Science in San Francisco to check out their extensive museum collection, home to nearly 1.2 million specimens! We were on a mission to observe a variety of sharks, rays and chimaeras and to bring back specimens on loan from the South African Museum. We were greeted on a foggy San Francisco Friday by Dave Catania, the senior collections manager for the Department of Ichthyology.
The California Academy of Science (CAS) Department of Ichthyology houses one of the largest and most important research collections of fish in the world. There are nearly 200,000 jars of preserved fish in the collection, representing nearly 11,000 different species. That is more than a third of fish known to science!
By looking up the unique identification number assigned by CAS, our guide Dave was able to bring us a whole cart of jars filled with old and unique animals. Catarina is working on a project to describe the sharks and rays from Oman, a country to the south east of Saudi Arabia. She photographed several specimens, including this Gulper Shark, to compare to other specimens from the region.
Just like a library, scientists can check out specimens from the museum like a book on loan. I was lucky enough to do just that with a new species of chimaera from the South African Museum. Chimaeras, or ghost sharks, are deep water fish with a skeleton made of cartilage, making them close relatives of sharks and rays.
When a new species is discovered a single animal is chosen, called the holotype, to represent the entire species. From this one animal I will record dozens of body measurements, take photographs and make observations in order to identify this chimaera to other scientists. After the specimen is described it will be added to a museum collection like the one at CAS for other scientists to observe in the future, a process called accession.
Proper identification and detailed observations are very important when describing a species. Take for example these two species of small catsharks from the Indo-Pacific Ocean. They are very similar in size, color and shape, but because they are available for scientists to look at, subtle differences start to emerge. Without detailed records and a holotype, identifying sharks (or any animal for that matter) can be difficult.
With jars in hand and our camera memory cards full, we make our way back to Moss Landing Marine Labs for more photos, notes and measurements.
On Labor Day weekend, Moss Landing Marine Laboratories' own Pacific Shark Research Center (PSRC) had the opportunity to dissect a 14.7 feet long common thresher shark (Alopias vulpinus). The female shark was found washed up on the beach on Moss Landing already dead.
The PSRC is part of the National Shark Research Consortium for the West Coast. Currently there are 7 students enrolled in this department led by the program director, Dr. David Ebert, also a MLML alumni, and a handful of undergraduate volunteers from San Jose State University and California State University: Monterey Bay all who are ready to learn more about elasmobranchs!
The students were pretty amazed to see such small teeth on such a large shark. The teeth on this animal say a lot about what it eats. Schooling fish such as sardines and anchovies, as well as cephalopods are its preferred prey. Thresher sharks are part of the mackerel shark order (Lamniformes) and excel at speed and long distances. A few examples of this order include, the white shark (Carcharodon carcharias), the makos, shorfin mako (Isurus oxyrinchus), longfin mako (Isurus paucus), the salmon shark (Lamna ditropis), and the porbeagle shark (Lamna nasus). These species in particular are endothermic, meaning that they can thermoregulate their own body temperature to several degrees warmer than the ocean water, allowing better foraging opportunities.
They also have big eyes to find prey and large gill slits for oxygen. Since these species are pelagic species, they require a lot of oxygen to keep moving. Lamniformes (mackeral sharks) breathe through ram ventilation, where the animal swims while opening its mouth. These species require constant motion or else they'll drown. However, some sharks have adapted to living life on the bottom, and can actively pump water pass their gills with their spiracles, which are tiny holes usually located behind the eyes on the shark. In larger oceanic species, the spiracles have lost its ability to pump water.
The dissection was a very exciting and rare opportunity, since thresher sharks are pelagic predatory fish, that spend their lives in the open ocean. There are currently only three known species of thresher sharks, the common (Alopias vulpinus), pelagic (Alopias pelagicus), and the big-eye thresher (Alopias superciliosus).
Previously it was thought that thresher sharks used to swing their tails around to catch their prey. However, a new study this summer show that they actually use their long caudal tails to stun their prey. Scientists managed to catch footage of the pelagic thresher shark (Alopias pelagicus) in action.
Students were able to take morphometric data of the shark by measuring everything from body length and fin lengths, counting the vertebrae, and noting of any visible scars or injuries.
One noticeable wound was the large propeller strike that was near the end of her body.
They also took tissue samples of the shark's muscles, reproductive organs, and liver to detect mercury levels. Since sharks are apex predators, meaning they eat at top of the food chain, toxins and heavy metals can bioaccumulate which can cause detrimental health problems if they are in high concentrations. Stay tuned to see if we found something revealing on what may have caused her death.
Contrary to Hollywood’s portrayal of gigantic man-eating sharks, the three largest species of shark spend their time peacefully roaming the ocean's surface munching on the ocean’s smallest creatures. Basking Sharks, the second largest species of shark, cruise the seas in search of plankton, filtering up to 2,000 tons of water across its gills per hour. Reaching lengths of thirty five feet, this shark exists worldwide, yet very little is known about how they live or where they go.
To discover more information about this vulnerable species, scientists from the Pacific Shark Research Center (PSRC) and the National Marine Fisheries Service (NMFS) have begun a new type of shark hunt. Unlike the crazed and frantic scenes from the JAWS movie, this shark hunt only requires a boat, camera and telephone! The Spot a Basking SharkProject enlists the help of local sea-farers to uncover the demographics and distribution of the California Basking Shark.
Once common along the California coast, these gentle giants are now a rare sight. In the past, these social creatures were seen in schools of hundreds or thousands; however since 1993 no more than three basking sharks have been spotted together. Fishing and eradication efforts by fishermen who believed them to be ‘man-eaters’ contributed heavily to their population decline. Despite the fishery closure in the late 1950s, Basking Shark numbers have remained low, mostly due to human impacts like vessel strikes, fisheries bycatch and illegal shark fining. Based on the decline of Basking Shark numbers and lack of species information, the International Union for Conservation of Nature (IUCN) has listed this species as endangered.
If you see a Basking Shark, the PSRC and NMFS want to know! These sharks can be identified by their large size, pointed snouts, and large gill slits that encircle the head. Basking sharks have dorsal fins up to three feet tall that are visible as they slowly swim along the surface with mouths wide open catching plankton. If you see a Basking Shark, call or email the PSRC with your location, date and time of the sighting and any photos or videos. Your information helps the PSRC document and understand these majestic and peaceful creatures.
Celebrate the return of the Grey Whales to the Monterey Bay at the Whalefest Monterey 2013 event this weekend Saturday, January 26th and Sunday, January 27th !
This event aims to bring public awareness to the marine non-profits that influence the Monterey Bay Marine Sanctuary by offering a variety of fun activities, events, and exhibits from over thirty organizations.
Our very own Pacific Shark Research Center will have a booth set up this weekend! Find us at the Causeway at Old Fisherman’s Wharf from 9am to 5pm.
The new Wave from Friends of Moss Landing Marine Labs is here! Inside are stories on the Drop-In Blog, PSRC’s Spot a Basking Shark Project, and the new Ichthyology faculty Dr. Scott Hamilton. To download a copy, click the front-page image above, or click here.
If you found out about the Drop-In from your copy of the Wave and are visiting our blog for the first time, welcome! We hope you’ll enjoy reading about our adventures. Click on the bullets below to find the stories written about in the Wave:
It’s amazing how many people are scared of sharks. I have over 500 dives over four years on the west coast and have only seen one large shark. It was such a neat experience to see a ten foot shark in the water – most likely a sixgill shark, which are not dangerous. During Open House the sharks will all treat you with respect (as you should them!). All the sharks we have are preserved, not living specimens, but it is neat to see them and appreciate them up close. This year we’ll have a salmon shark on display – be sure to come check it out!
French international student and shark lover Marie Cachera cuddles a leopard shark from the MLML collection. Marie conducted a diet study on the starry skate as part of her Master’s thesis while visiting MLML for five months in 2009. Despite our location in a podunk town, the caliber of research of Moss Landing Marine Labs has attracted scientists and students from all over the world. Read an interview with MLML’s current international student Edem Mahu from Ghana.
There are fewer rude awakenings for a sleepy Pacific Sleeper Shark than to get hauled up in a net during a government fishing survey. But for fish biologists, it’s an incredible opportunity to get a photo with the “big one!” Ichthyology student Erin Loury poses with the unexpected catch while volunteering with the National Marine Fisheries Service groundfish survey as part of a partnership with MLML’s Pacific Shark Research Center. Don’t worry, the shark was released alive – but probably a little grumpy.
The gulls first caught my attention, a small flock in a tight swarm above the waves just beyond my surfboard. Others floated on the surface below. Suddenly the sea below them erupted, and the birds on the surface took flight. A frothy pink spray of water shot into the air; there was blood in the water. As the water calmed the gulls swooped and dove, feeding. A few seconds later the scene repeated itself, another violent splash of bloody water. My instincts were screaming, telling me turn and paddle in, to get out of the water.
My curiosity got the better of me, and I sat transfixed as something was being ripped to pieces only a few hundred yards away. Other gulls were making a beeline to join in the feast, and the flock grew. I watched the attack for another minute, until at last a large black fin broke the horizon and my suspicions were confirmed. This was no sea lion or orca, but a large white shark, eating lunch.
I swung towards the beach, catching my last wave on the way in. As I crested the dunes to get a better vantage, I saw the shark hit twice more. I ran to the parking lot to grab my binoculars. By the time I looked back to sea, the gulls had stopped flying, all were swimming on the surface. I peered through the lenses for a few more minutes, but the attack had ended. I walked back down to my car, relieved that I had been a witness to a raw display of nature’s brutality, rather than an unwilling participant.