Blue Heron Bridge Trolls III

[Scuba_Jenny]

Been thinking about the seahorses at BHB vs finding them off the beach. Am thinking there are enough people combing through the little things that surely they would be seen if out there. So, wondering if off the beach they are transient and at the bridge residents?

 

[Green Frog]

I don’t know, but for all of them I HAVEN‘T been able to see, they must pass through faster than Seabiscuit!

 

[tarponchik]

Love those Juvenile Gray Angelfish. I can’t remember the last time I got to see them myself in the water, but used to see them all the time. It took me some hard study to learn how to distinguish Julie Grays from Frenches.

Assorted juvenile angels couple of weeks ago.

 

[tarponchik]

I've left a couple of welk shells that I found on the ocean side of Singer for local hermits, hope they can use them.

 

[Pipehorse]

Been thinking about the seahorses at BHB vs finding them off the beach. Am thinking there are enough people combing through the little things that surely they would be seen if out there. So, wondering if off the beach they are transient and at the bridge residents?

I don’t know, but for all of them I HAVEN‘T been able to see, they must pass through faster than Seabiscuit!

Blue Heron Bridge is one of the most top three surveyed sites in the REEF database, 2641 surveys. Molasses Reef in Key Largo has about the same number, and Bari Reef in Bonaire has a 3900 surveys.
Since there is a lot of data for the site we don't necessarily have to guess about the presence or absence of a particular species, in this case Lined Seahorse. I apologize for the crudeness of the chart below, I have not used excel for awhile.

Sighting frequency is a percent of how often a specific species is observed against the total surveys for a given area. I did twelve separate queries of the database by month from July 22, to June 23 to find the corresponding sighting frequency for Lined Seahorse. The horizontal axis of the chart is date, corresponding to below
1=Jul 22
2=Aug 22
3=Sept 22
You get the idea
Vertical Axis is the sighting frequency.

So according to the chart Jan, Feb, and March are when you have the best chance of seeing Lined Seahorse. Sightings taper off dramatically in April dropping to zero during the summer with the exception of July being an anomaly, and start to pick back up in October. What would be interesting is an overlay of temperature. Temps do start to drop in October hit a low in January and start to rebound around April, seems as if the seahorse prefer colder temps. So temperature vs. sighting frequency graph added.

Also habitat probably plays a key role here. Most of the Lined Seahorses I find at the bridge are in water shallower than 10 feet, and situated among the algae.

From this I would argue that Lined Seahorse are transient, and not year round residents. I would also argue that temperature seems to play a large role in their presence. What is not included here is a similar chart of Long Snout Seahorse which have lower sighting frequencies than Lined Seahorse.

 

[Green Frog]

Thanks @Pipehorse. Either I’ve been looking in the wrong places or in the wrong way. I guess I’ll have to slow down in likely places and look more carefully.

 

[Green Frog]

Thanks to you @tarponchik. I’ve always had a soft spot for juvenile anythings (except maybe delinquents!) Must be related to why I got into teaching. Those are some very nice pix.

 

[Scuba_Jenny]

Thanks @Pipehorse. Either I’ve been looking in the wrong places or in the wrong way. I guess I’ll have to slow down in likely places and look more carefully.

When people ask how to find stuff at the bridge, I always tell them to slow down. Then slow down some more. And more... Problem is most people are not weighted correctly, or have poor buoyancy skills which means moving keeps them from sinking or floating.
Not accusing you of poor skills. Heck, I've never met you.. If I did meet you and you plow through the water, I would discuss privately...

 

[Scuba_Jenny]

Blue Heron Bridge is one of the most top three surveyed sites in the REEF database, 2641 surveys. Molasses Reef in Key Largo has about the same number, and Bari Reef in Bonaire has a 3900 surveys.
Since there is a lot of data for the site we don't necessarily have to guess about the presence or absence of a particular species, in this case Lined Seahorse. I apologize for the crudeness of the chart below, I have not used excel for awhile.

Sighting frequency is a percent of how often a specific species is observed against the total surveys for a given area. I did twelve separate queries of the database by month from July 22, to June 23 to find the corresponding sighting frequency for Lined Seahorse. The horizontal axis of the chart is date, corresponding to below
1=Jul 22
2=Aug 22
3=Sept 22
You get the idea
Vertical Axis is the sighting frequency.

So according to the chart Jan, Feb, and March are when you have the best chance of seeing Lined Seahorse. Sightings taper off dramatically in April dropping to zero during the summer with the exception of July being an anomaly, and start to pick back up in October. What would be interesting is an overlay of temperature. Temps do start to drop in October hit a low in January and start to rebound around April, seems as if the seahorse prefer colder temps. So temperature vs. sighting frequency graph added.

Also habitat probably plays a key role here. Most of the Lined Seahorses I find at the bridge are in water shallower than 10 feet, and situated among the algae.

From this I would argue that Lined Seahorse are transient, and not year round residents. I would also argue that temperature seems to play a large role in their presence. What is not included here is a similar chart of Long Snout Seahorse which have lower sighting frequencies than Lined Seahorse.


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Circumstanial findings of seahorses confirms this is mostly true with the anomonly being the summer of '22 when seahorses were present for months then all suddenly disappeared. The reddish one was within about 10' diameter for 6 weeks or longer. They definately do come and go with the seasons.

 

[Green Frog]

Thanks @Scuba_Jenny. As stated in my previous post I’d already come to that conclusion. You have definitely confirmed my beliefs. Now that I’m almost halfway through my seventh decade I’m tending to slow down anyway. In fact, my next trip will probably involve finding one likely patch reef and spending my dive examining it in excruciating detail. I’ve been wanting to go back to some close up work anyway.

Back in my early days with Nikonos V about (1995 or so) I picked up a cheap add on close up lens. I made one or two very fruitful dives and got some really nice pictures, but then I caught big-fish-itis and put that lens aside never to use it again. Now I’m older and wiser (or maybe just slower) and getting up close and personal is more attractive once again!

Thanks again!