Fish communication

Fish Communication

Fish aren’t traditionally perceived as having personalities, but they’re anything but the dumb automatons that our ancestors would have us believe.

Underwater organisms don’t have the facial musculature that we as primates have evolved. Quite simply they haven’t needed it, therefore they haven’t acquired it through natural selection.  However they have  been evolving and surviving on this planet for over 500 million years.

And they do communicate to each other.

How do fish sense each other?

In a Darwinian world where survival is paramount, the lateral line has become their first defense and sensory organ. This first level of communicating allows the individual to feel what’s around it. The layer of sensory cells that run along the flanks of most fish, detect the pressure changes in the surrounding environment. This system has evolved to the point where fish react with an almost simultaneous motion to an external stimulus.

silver fish

school-silver-fish-evade-predators-footage-007763027_main_xl.mp4

How do fish school in such dense numbers without colliding?

Fish have a sensory barrier around them, a kind of bubble that they can perceive. This bubble is squashed as objects or animals move around the individuals perception. They can sense their immediate surroundings in this fashion.

Some fish such as the freshwater knife-fish even generate electric fields. These fields are influenced by their surroundings, especially other animals, and the knife-fish react to that reflection of their own electric field and use it to locate prey.

Sharks have an extremely sensitive network of electroreceptors that can detect the smallest electric fields from other animals.

Vision is also important in the depths of the ocean especially in the upper Euphotic zone (where photosynthesis can occur). Most of the longer, lower energy wavelengths are lost quickly, absorbed by the water column. Red light disappears first, then orange, then yellow… leaving only blue as you descend to the furthest depths of the Photic zone (The depth that light can penetrate through water).

How do fish display their intentions?

Contrast over actual color makes a big difference at depth and aquatic animals can use that to their advantage to display their intentions. Humbolt squid for example can change their entire body from red to white and back like you can flick a light switch. They do this at depths far beyond red light can be seen (200m-700m) so appear in this twilight world as if they are going from black to white like individual morse code signals. What they are saying to each other is beyond our understanding.

Closer to the surface we have fish species that utilize many more frequencies of the electromagnetic spectrum including the ultraviolet wavelengths.

underwater fish
The stripes behind the eyes of this saddleback Toby reflect ultraviolet wavelengths.

On a more day to day scenario, most SCUBA Divers and snorkelers who pay attention will have noticed that some species of reef fish can have drastically different colourations. Take the Big eye crescent tail as an example.

school of silver and red fish
The red phase can bleach out to a silver within seconds

When it’s calm an individual will be a deep red, when stressed it can bleach to a silver. Similarly when fish such as the Big-nose Unicornfish visit cleaning stations they can display complex patterning only for it to fade to black once the fish swims away.

When fish think about sex

During spawning aggregations many fish species undergo drastic color changes that signal their readiness to participate. The bumphead parrotfish are pretty obvious during their aggregation as their heads bleach white from the usual green.

Bumphead Parrotfish spawning coloration
Bumphead Parrotfish spawning coloration

In the Caribbean, Nassau groupers migrate in groups to their annual spawning grounds and are often led by an individual who sports a drastically different body patterning. Once at the spawning site they all adopt an even more extreme color change. For further reading see this article.

Bohar Snappers have a variety of different colorations during their spawning aggregations, sometimes two small white spots appear on their dorsal area, others adopt a bleached blue hue rather than their usual russet red. Others adopt a mixture of the two with a red belly, a white stripe down their flanks and a bluish dorsal area. As I pour over the many spawning rushes I’ve filmed of this species I cannot see any distinguishable pattern in whether a female adopts a certain body color prior to her egg releasing rush.  A pattern may emerge after further observations though.

See this clip of a small group interacting in preparation for spawning. The female with the broken dorsal fin is being nudged by a number of males. Maybe this nudging is meant to initiate her egg releasing rush. Maybe it’s the males trying to ascertain if she is ready or not….?

Bohar snapper spawning aggregation
Bohar snapper spawning aggregation

For a really in depth look at this behavior and other similar color changes seen during spawning, Tony Wu has written an excellent series of articles that are well worth a read.

Additional articles and films of Palau’s spawning aggregations can be found here.

Communication between species

It has been shown that fish communicate between species. In the case of the Grouper and Moray Eel, the Grouper will shake it’s head next to the Eel to signal an intention to start hunting. The strategy has been shown to be more successful at catching prey. 

fish communication
Grouper, Moray cooperative hunting. Palau
Underwater acoustics in fish

Underwater acoustics is not just the tool of marine mammals, many fish  are also extremely vocal. Have you ever swum over a reef and heard all the clicking noises? This is a medley of fish and crustaceans each with their own message. Usually the message is “this is my territory, keep out”. Sound is an extremely useful form of communication in the aquatic environment as sound travels much further than light. A fish can remain hidden whilst  letting an intruder know that it’s encroaching. Groupers often growl or rumble from within their hiding place. The behavior across a multitude of species was documented here and demonstrates the rich complexity in coral reefs.

Can we talk to fish?

So in conclusion, whilst fish and other aquatic organisms like cephalopods might not be able to convey their intentions through facial cues like we can, they are extremely in tune with and aware of their environment. They are able to send messages that even other species can understand. The fact that we might not be able to understand them is perhaps our failure rather than theirs.

Have you had any interesting interactions with aquatic wildlife? I’ve not begun to get started with the marine mammals here, whole different kettle…..so there’s still a load more to talk about. Feel free to leave a comment in the section below. Do you know the difference between a head nod and a shake in Moray Eels, can you predict when a Stingray is about to lift up and depart from it’s resting place? So many more topics and examples for the future.

For more info on filming underwater  and learning about your subjects this article may well be helpful.

Until next time, Cheers!

Richard

 

References

http://jeb.biologists.org/content/216/13/2515

The evolution and development of vertebrate lateral line electroreceptors

Clare V. H. BakerMelinda S. ModrellJ. Andrew Gillis

Underwater photography workshops and training in Palau

Underwater photography is a common art form these days with cameras readily available for reasonable prices. A large proportion of divers now have housed cameras ranging from a cell phone to the latest flagship behemoth “HMS Nikon”. Many also find enjoyment in attending an underwater photography workshop as part of their dive vacation.

Underwater photography is art with a physical challenge too. The best photographer on land could be terrible underwater if they’re not a competent diver.

Underwater cameraman Palau
Sunbursts were the order of the day
Underwater photography should be fun

When everyone has a camera and is “happy” with what they’re doing it’s nice to be asked by someone to help them improve their shooting.

Underwater Photography workshop in Palau
A large school of fish offers the creative underwater photographer a multitude of imaging options.

On this occasion my student wanted help across a range of subjects. Here’s a run down of things we covered:

….and camera basics

Many issues that lead to dissatisfaction in underwater photographers are down to the inherent intelligence of cameras. Especially with point and shoots and the more automatic varieties. What I mean is that cameras are often thinking too much and because they are mostly not designed with underwater photography in mind, they can make it more of a challenge to get the best shots out of them. Auto focus is a big one for this.

underwater wildlife, Palau
Once you find a cooperative subject shoot it in as many ways as possible

Dissecting what the camera is trying to do for you is the first step. Turning off “intelligent” facets of it’s character often requires reading the manual and a little experimentation. Get to know your camera.

Next comes the basic shutter speed/ aperture/ISO balancing knowledge that all photographers worth their salt should have a rudimentary understanding of. It’s not always available but being able to control them in the camera is so much more rewarding….. and challenging…. but that’s what I’m here for.

underwater photography palau
Subjects that don’t move too much and will allow you multiple attempts are good to start with

What will absolutely ruin a good underwater photography dive is when the housing doesn’t perform so I always advocate spending as much time as you can on preparation. All it takes is one o-ring or one connecting rod out of place and you have a camera that won’t work on the dive or worse is flooded. Be prepared.

After that we have the lighting and strobe positioning that is so important underwater. Correct or incorrect strobe use will make or break a shot, so developing the mindset of creating a studio  and moving your lights within it and around your subject will reap great rewards.

Bespoke one on one workshops

Often the student photographer has a certain shot in mind or wants to improve on certain elements of underwater images in general. This time we were going for sun beams through the water as a background to our perfectly placed subject so we focused on that when possible.

underwater photography student palau
Spending the safety stop shooting sun bursts and beams

Overall, it comes down to patience and practice, but with an hour of preparation and coaching before the dives we had the set up and basic operations down, after a few trial shots underwater on stationary objects we have a better feel for strobe power and ball park exposure settings. Then after that it’s about looking for subjects and having fun. A few over the shoulder views by me allows a real time feedback for the student and quick adjustments when necessary. Between dives a more in depth discussion as we review results.

Certainly a faster learning curve than the old slide film days………

Contact Lightning Strikes for availability of courses or workshops, individuals or groups are welcome.

For more underwater media articles follow this link

Cheers

 

Richard

 

Using the 6K RED Epic Dragon in Palau

Richard Brooks shooting with the RED Dragon 6K camera
Filming Manta aggregations in the north of Palau for a cinematic documentary with the RED Dragon. (image: Pete Zuccarini)
Cinematic Palau

Lightning Strikes was called upon to provide location advice and be second camera for a cinematic documentary being shot in Palau. The best RED 6K cameras were used for this large budget shoot in Palau.

To provide amazing footage of Mantas we went up north to film them  aggregating in the northern channels. This is part of their annual migration that occurs at this time of year.

Make it a RED camera Palau

We have been using a RED Epic Dragon with the Arri 8mm prime lens on front for the widest, closest images possible and we were not disappointed.

Late in the day we had Manta barrel feeding in shallow water surrounded by huge schools of fish that reacted in explosive and dramatic fashion as the mantas looped through them.

This footage may well end up in the finish documentary or could find it’s way into other productions. Either way, the 6K sensor from the RED provides incredible Raw footage from this day and many others we have been filming throughout this shoot.

To see other work check out the main website here

Watch other posts in this behind the scenes blog here

Cheers

Richard

Spawning aggregation dives in Palau

As natural events go, very little compares to fish spawning aggregations and it’s the time of year again to be diving Peleliu. Both the Sailfin Snapper (Symphorichthys spilurus) and Red Snapper (Lutjanus bohar) are starting to aggregate along the east reefs of Yellow Wall and Peleliu Express to the corner.

For those intrepid divers, early morning dives just before the full moon will find them spawning in their thousands. Also making an appearance are the predators such as Bull Sharks and Oceanic Black Tips.

How to find the aggregations

I joined Dari Divers for this trip as they know exactly where and when to jump in, even once on the reef they can interpret the fishes behavior and know how to approach them. Check out the edited short film from this year:

 

Check out last years showreel with footage from the Red Snapper spawning dives here.

Watch this space for updates as we return to document this impressive natural event.

 

Cheers

 

Richard

 

Palau diving with the best

Promoting the best

Over the last few months I’ve been diving with Dari Dive Palau. Together we are planning on showing all the cool fish, sharks and mantas at new locations they know. As well as showing the best in Palau diving, they asked me to put together a short film of the regular features such as the spawning dives, aggregations, Blue Corner, Blue Holes, German Channel etc to begin with, which you can see here:

I have found Dari Divers to be particularly good. Apart from offering Nitrox, great lunches and taking small groups to the best sites, I’m finding that they have a deep understanding of the timing of natural events. This rich knowledge enables them to put their divers in the water at exactly the right time on the right day to witness nature at it’s best.

See another film I produced on another trip with them here.

Palau diving with the best

After diving at a professional level for close to 20 years, in a wide variety of locations and shops around the world, I hope I can say that I have a reasonable amount of experience in the business of recreational diving. Many shops are very busy always running at 150% (great for business/bad for customer satisfaction). Some cut corners and the customers are left with substandard guides, poor rental equipment, boats that break down etc. It’s a fine blend of personal attention and the excitement of discovery and adventure that for me makes Dari Divers stand out for a great diving experience in Palau.

Palau Diving
Side-mount diving Palau

 

Making the film

All the underwater stuff is shot on the Canon 5D3 running Magic Lantern  capable of outputting 4K Raw footage. For more info on this set up see this post

Aerials were shot using the DJI Inspire 1, hand launched and caught from the bow of the boat during the surface intervals.

For the editing I looked at a different aspect ratio this time. 2.35:1 instead of the usual 16:9. This trial is to see how it holds up over time and initially I like the look. To me it makes the screen bigger even though it’s actually smaller…..go figure. It’s a trend that’s becoming more prevalent lately.

Let me know in the comments section below what you think to the film and whether or not the 2.35:1 ratio works for this sort of thing.

Watch out for new media coming from this new collaboration as well as views from new as yet undisclosed sites around Palau.

See Dari Dive website here

 

Cheers

Richard

 

How to become a professional underwater cameraman

 How do I become an underwater cameraman?
how to become a professional underwater cameraman. Underwater Cameraman Palau. Underwater photography
Underwater filmmaking needs you! Photo courtesy Eric Goh

I get a lot of e-mails asking me how to become a professional underwater cameraman, or to use a professional underwater camera or even how I’ve got to where I am with my underwater photography career. So I thought I’d put together a short blog to help all those aspiring shooters.

Unfortunately there is no one course or definite route. The more successful underwater camera operators you meet the more varied the stories  you’ll get. For the sake of this, here are some recurring similarities.

Most of it may seem like common sense but hopefully my contribution offers you some insight.

If any readers have ideas that they can offer, things that I haven’t encountered or mentioned it would be great to hear from you. Please leave a comment at the bottom to help every aspiring shooter out there.

how to become a successful underwater cameraman. Underwater Cameraman Palau
Waiting for the sun to set before filming a Grouper spawning aggregation, Little Cayman, circa 2005

Continue reading “How to become a professional underwater cameraman”

Why you should dive Balicasag Island

Should you find yourself in the Bohol/Panglau region of the Philippines and you’re a diver, there is a place I can thoroughly recommend. Even if you’re not a diver, this place could possibly persuade you to be one.
Every dive shop in the area offers trips there, because it is so good, it’s unavoidable in fact I would say. As soon as the weather is good enough they said, “we’ll go”.
So, with a recommendation like that and a shop like Philippine Fun Divers providing me with good rental gear, a great boat taking me there and expert guides I couldn’t really refuse.
Good thing I didn’t, because even though the weather was still a bit….”marginal” the diving was anything but that.
Once the Banka boat had approached the low lying sand fringed island, myself and the 2 other divers got geared up, had a briefing from our DM Greg and we got in. Almost immediately I’m seeing stuff I’d not seen before or multitudes of critters I see rarely. One of my favorites is the little Tobies or Pufferfish.

The little Tobies and Pufferfish often have highly reflective markings that when hit by your lights really shine.

Continue reading “Why you should dive Balicasag Island”