Looking for horn sharks in Baja California & Sonora

[scanfield]

Greetings!

I'm a researcher based in Hawaii, and I'm looking for tips and advice re: diving in Baja California and Senora. I'm looking for horn sharks (California and Mexican horn sharks, Heterodontus francisci and H. mexicanus, respectively).

Has anyone seen horn sharks while diving around the peninsula, or in the state of Senora? If so, what was the season? Do you remember the approximate depth? In California (USA), they tend to be shallow (< 40fsw).

I'm considering the following sites:

- La Paz and/or Cabo SJ
- Loreto
- San Quintin
- San Carlos

If anyone has experience diving these sites, intel about horn shark sightings would be mightily appreciated! These aren't my final selections, so if anyone has any recommendations, they would be very helpful. I have my hands on samples from Bahia Tortugas, and I'm trying to spread out my sampling for a good population genetics study.

Many thanks,
Sean

 

[diversteve]

I've never seen any off San Carlos but if I had to pick a likely spot it would be the SW side of San Pedro Island since it's very reminiscent of La Jolla - just less weed cover, But very similar in terms of channels and overhangs - also lots of tasty crustaceans. And shallow - much of it around 60' or less.

Who might really know - the staff at 72 Aquatics in Tucson or El Mar Diving in Mesa Az, both own popular dive boats there and run trips down most weekends in the summer/fall - it's still t-shirt warm in mid-October but cools off fast after that - in winter drysuits are used.

It's our go to warm water diving from Arizona. Marina Terra hotel is decent and you can walk with gear to most of the dive boats moored in the marina behind it.
72 Aquatics | Swim, Snorkel, Scuba, Travel
El Mar Diving Center, Your Arizona Scuba Diving Center

Guaymas is the regional airport and is a $25 cab ride to Marina Terra. There;s probably still regional air flights from Phoenix - maybe American Eagle (AA) post USAir merger.

San Carlos, Sonora, Mexico

 

[scanfield]

I've never seen any off San Carlos but if I had to pick a likely spot it would be the SW side of San Pedro Island since it's very reminiscent of La Jolla - just less weed cover, But very similar in terms of channels and overhangs - also lots of tasty crustaceans. And shallow - much of it around 60' or less.

Who might really know - the staff at 72 Aquatics in Tucson or El Mar Diving in Mesa Az, both own popular dive boats there and run trips down most weekends in the summer/fall - it's still t-shirt warm in mid-October but cools off fast after that - in winter drysuits are used.

It's our go to warm water diving from Arizona. Marina Terra hotel is decent and you can walk with gear to most of the dive boats moored in the marina behind it.
72 Aquatics | Swim, Snorkel, Scuba, Travel
El Mar Diving Center, Your Arizona Scuba Diving Center

Guaymas is the regional airport and is a $25 cab ride to Marina Terra. There;s probably still regional air flights from Phoenix - maybe American Eagle (AA) post USAir merger.

San Carlos, Sonora, Mexico

Hey diversteve,

Thanks, I'll look into it! What you say about San Carlos makes sense. A collaborator in Mexico says it's mostly sandy-bottom there, and horn sharks do prefer rocky reef habitat, especially as adults.

If anyone else has other Intel, again, it would be much appreciated. I'm aiming for this summer, but might be restricted to winter if the permits take too long.

Cheers,
Sean

 

[diversteve]

Not my video but this is in the general area..The boat is Ocean Spirit owned by 72 Aqustics. Usually more crowded than that....

 

[scanfield]

Not my video but this is in the general area..The boat is Ocean Spirit owned by 72 Aqustics. Usually more crowded than that....

That habitat is interesting. Part of me thinks I should be able to find horn sharks there, but I also noticed a lack of typical prey items. On top of that, I need to consider seasonality.

Thanks a lot! I used YouTube videos as a resource a lot when I was scoping out California dive locations. Perhaps unsurprisingly, those spots (Malibu, Redondo Beach, Laguna, and San Diego) had a lot more information published about them. Mexico is proving a lot more difficult!

 

[AZTinman]

For what it's worth, I've no doubt that you're having difficulty finding a location in Mexico where horn sharks are numerous; this is particularly true of locations in the Gulf of California. The species is present, but probably not in the numbers you'll find in locations off the Pacific Coast.

Personally, I've done quite a few dives off San Carlos from the Ocean Spirit (Ocean Sports boat) and Pesquita (El Mar Dive Center's boat). So far, I've never seen a horn shark. Again, this is not to say that the species isn't there somewhere. You'll spend a lot of time looking unless someone knows of an area in the Gulf that's frequented by horn sharks.

-AZTinman

 

[Azur Salino]

I live in Loreto and run a dive shop here, so I get to explore the depths often
We do see horn sharks around the south side of the National Park, the other day we found several horn shark eggs. In the next weeks I'll be exploring a few other reefs where I heard you can find these easy. Will keep you posted!

 

[AZTinman]

I received an alert concerning this thread when Azur posted a response today. Azur's post about finding horn sharks in the Loreto area is great information.

The potential presence of horn sharks and the actual range of the species in the Gulf of California interests me. While I've never seen a horn shark while diving on the Sonoran side of the Sea of Cortez, I have found a reference to the species in a 1980's publication with an extremely poor photograph of one taken off Isla San Pedro Martir. The island is located just south of Isla San Esteban in the Midriff Islands. The location is north of San Carlos, Sonora and Isla San Pedro Nolasco.

I'll be doing a trip down to Bahia de Los Angeles in a few weeks. In addition to seeing what I can find, I'll visit with some locals to see what insights they may offer. Horn sharks tend to be one of those species that prefers to be active at night and lay low during daylight hours.

-AZTinman

 

[scanfield]

I live in Loreto and run a dive shop here, so I get to explore the depths often
We do see horn sharks around the south side of the National Park, the other day we found several horn shark eggs. In the next weeks I'll be exploring a few other reefs where I heard you can find these easy. Will keep you posted!

Oh, I just saw this after posting a reply to you in another thread! Thanks so much!

 

[scanfield]

I received an alert concerning this thread when Azur posted a response today. Azur's post about finding horn sharks in the Loreto area is great information.

The potential presence of horn sharks and the actual range of the species in the Gulf of California interests me. While I've never seen a horn shark while diving on the Sonoran side of the Sea of Cortez, I have found a reference to the species in a 1980's publication with an extremely poor photograph of one taken off Isla San Pedro Martir. The island is located just south of Isla San Esteban in the Midriff Islands. The location is north of San Carlos, Sonora and Isla San Pedro Nolasco.

I'll be doing a trip down to Bahia de Los Angeles in a few weeks. In addition to seeing what I can find, I'll visit with some locals to see what insights they may offer. Horn sharks tend to be one of those species that prefers to be active at night and lay low during daylight hours.

-AZTinman

Thanks so much!

What I've found is that they're really, really good at hiding. There have been several sites where a handful of people told me I wouldn't find horn sharks, but because I had time, I went and looked anyway, with great success. That's not to say I doubt what you're saying here at all - but I do weigh it against those experiences a little bit. Unless people are looking for them carefully and specifically, they're incredibly easy to miss. That said...there have absolutely been sites where people said I would find them, and I found none (*cough* Malaga Cove, CA *cough*)! And, due to budget constraints, I've got to be careful about spending too much time on dud sites, so these insights are especially valuable.

Honestly, I may skip Sonora (to focus on the Baja Peninsula as a barrier to dispersal by itself), and focus my sampling efforts on the following sites:

- San Quintin (< this may involve cooperation from fishermen at fishing camps/villages)
- Magdalena Bay (they're well-documented here)
- Cabo San Lucas (questionable...)
- La Paz
- Loreto

I really appreciate you taking the time to respond, and maybe even report back. I can't tell you how helpful that is. I thought I was flying blind in California...this is a whole different beast.

- Sean