Recent Expeditions

Expeditions

Bali 2015

South Africa 2006

South Africa 2004

Taiwan 2000

Our team is investigating the Molidae through two complementary approaches–pop-off satellite archival tagging of individuals and genetic analysis of global populations.

Select a topic below to read more...

TAGGING

Our tagging work involves special tags called pop-up archival transmitting (PAT) tags. PAT tags are secured using a plastic anchor inserted at the posterior base of the dorsal fin. While attached, the tag records and logs temperature, depth and light intensity. From light intensity, day length and local noon are calculated. This information in conjunction with sea surface temperature measurements is used to document location. After a pre-programmed time, the tag releases floats to the surface and uploads its data to satellite. Thus, daily information on movements and behaviors are obtained without having to relocate either the fish or tag. Should the tag release early or the fish die and sink, the satellite tag will automatically surface and initiate transmission. (For more information on satellite tags see http://www.wildlifecomputers.com/Satellite%20Tags/PAT.htm)

Our team has tagged Mola mola off San Diego (California), Capetown (South Africa), Kamogawa (Japan) and Queensland (Australia).

We have also tagged Masturus lanceolatus off Hua Lien (Taiwan).

To date, six tags have reported and we are in the midst of analyzing our data. We’ll be posting our exciting results soon so stay tuned. The sunfish have some dark secrets to divulge.

The mola team recently returned from a successful tagging trip to Japan where 2 more tags were deployed on Mola mola with the help of the Kamogawa SeaWorld and the Fisheries Cooperative Association of Kamogawa. These tags are due to release on Halloween 2003. Whilst over in Japan, the team also discovered a 1996 record of a Japanese Mola mola that appears to be a new world record! Check out: http://news.nationalgeographic.com
/news/2003/05/0513_030513_sunfish.html.
The mola team is also planning to tag more sunfish this July and August off the coast of California. And come December, theyll be heading to South Africa.

GENETICS

Hundreds of tissue samples have been analyzed from mola populations spanning the globe. Some striking differences between certain populations are emerging. We may even have two new species of giant ocean sunfish. So stay tuned on the genetics front as well.

COMMERCIAL IMPORTANCE and EDIBILITY

While unpopular in Europe and the United States, molas are eaten throughout Asia. Taiwan and Japan are the largest markets. All parts of the mola are eaten including the skin, fin muscles, backbone, testes, and gut which is viewed as a delicacy. In Taiwan, the gut is served as "Dragon Intestines."

Fish Scientist Humor - YouTube

Unlike their pufferfish relatives, e.g. Fugu, molas do not carry the deadly neurotoxin, tetratrodotoxin (Saito et al 1991).

BYCATCH

Mola mola is the most common bycatch of the drift net fishery, which targets broadbill swordfish of California and Oregon. According to reports from the National Marine Fisheries Society Southwest Region, between 1990-1998, 26.1% of the drift net catch consisted of the common mola, which translates to a catch of 26,503 individuals. 42.1% of the total discards were mola (Rand Rasmussen, pers comm).

In the Spanish driftnet swordfish fishery on the Mediterranean side of the Gibraltar Straits, Mola mola constituted 71% of the entire catch in 1992, 93% in 1993 and 90% in 1994 (Silvani, L. et al, 1999).

Until we establish baseline data on these fishes, we have no way of gauging how such capture rates are affecting the wild stock.

Claire searching for sunfish Photo by T. Thys

Brett and Marina investigate mola food on the beach of Langaban

Cape fur seal ( Arctocephalus pusillus) posing as a sunfish
Photo by B. Hobson

January 06 Tag Team
From the right, Brett Hobson, Tierney Thys w/Marina Hobson, Michael Farquhar, Timony Siebert, Claire Taylor, Vince Calder
Photo by Two Oceans Staff (click for larger image)

Vince and Tierney searching for sunfish. Photo by M. Farquhar

Measuring the sunfish with Timony holding the fin. Photo by N. Townsend

Tagged sunfish with Capetown in the background
Photo by N. Townsend

From the left: Kevin Olivier, Natasha Townsend, Gerhard Beukes, Timony Siebert, Toshiki Matsuyama, Kaoru Satonh. Bottom: Michael Farquhar
Photo by Kentaro Amemiya
(click for larger image)

Tag Teams

In January 2006, members of the US mola team (Tierney Thys, Brett Hobson and Marina Hobson) traveled to Capetown, South Africa to assist Two Oceans Aquarium staff in satellite tagging two Mola mola as part of a PADI Project Aware Foundation grant awarded to Two Oceans.

Tierney
Tierney calling all molas
Photo by M. Farquhar

During this visit Thys presented results from the 2004 South Africa tagging expedition where 2 Mola mola yielded strong datasets. The 2004 expedition was funded in part by National Geographic and a AAAS grant for Women's International Science Collaboration. Thys also met with Samantha Petersen from Birdlife International. Petersen and her fisheries observers including Zoe McDonell have been recording large numbers of sunfish caught as bycatch in South Africa's mid water trawling operations for horse mackerel (Trachurus trachurus capensis). McDonell is currently writing up these data as part of her Masters thesis with the University of Capetown.

While the trip proved fruitful on many accounts, tagging proved difficult. Water temps were consistently low (hovering around 10 C) and winds were high. Only three sunfish were encountered during the search days of January 4th-10th and none of them proved taggable.. Tagging would have to wait until later in the year.

On March 10th, conditions proved perfect and the staff from Two Oceans took to the water. Water temps were between 12 and 13 C and two good sized mola were tagged by Mouille Point and Bantry Bay. The South African team this year was comprised of skipper Michael Farquar, divers Claire Thomas, Vince Calder, Timony Siebert, Gerhard Beukes, Kevin Olivier and Zaid Manquest, photographer Natasha Townsend and Patricio Garratti who lent vital shore support. Toshiki Matsuyama, Kentaro Amemiya and Kaoru Satoh from Tokyo Sealife Park also joined the fun as able assistants.

These tags are due to release on August 24th 2006. So stay tuned!

Getting ready to tag. Photo by N. Townsend

Smooch! Photo by N. Townsend