Down to the sea; 10; Conversations at Sea

What our croakers and their class of fish or a certain fish. Well I think they're a class of fish according to my book because a different program is a different kind of fish and their girl per family. And what is the progress. Sounds like it. Was hard to tell. Hard to take the plane down like a frog. More than anything I know. Do you think it has any. Any meaning to other fish croaking sound or would you suppose it might be a warning or something. Thank you I'm. Going to. Have some. Thanks Tony. Coffee. Or fair thing. That fisherman was recorded on the municipal fishing pier in San Diego is an observation that most everything does talk or communicate in some way is a feeling held by many peculiarly about those animals that walk on this earth with us. But how about the fish of the sea. Do they talk. I think indeed as silent as they might appear to be. Sound in the depths of the ocean

conversations at sea. If you will is the topic of this edition of down to the sea. There are many legends about creatures from the sea carrying on conversations with man and had least in our cultural background. Most of these legends are concerned with seals or seal folk as they were and still are in some cases referred to on the Channel Islands off England and Scotland and in Scandinavia there are widespread stories about silkies the seals that turn into men for short periods of time and there are beautiful legends about Seal ladies lovely women who walk the earth part of the time only to return to the off shore rocks in the guise of a

seal where they frequently sing of their sadness. The seals are in reality children of the King of Lochlann under spells they were so wise and brave and beautiful. Their stepmother hated them. So much did she hate them but she spent seven years with a magician. Learning the dockets. Arts of magic. Until finally she had mastered several spells. She then cast spells upon the children. So that they would be half fish and half human for ever. As long as the wave should be on the shores of Lochlann. Indeed you can tell by looking into the eyes of a seal that it has King in the blood. Three times a year during periods of a full moon. The SEALs turn into humans and wander the land.

It brings a world of envy and sorrow to the heart. To see others ruling the kingdom. Which is their. By right of blood. Long ago but not too long ago. A young man was walking on the shore under the full moon. When he came upon a seal lady Lloyd washing myself in a stream. He immediately fell in love with it and put it into a deep sleep with the charm that he had. Carried her to his cottage where the night was spent. But oh when the awakening paying he had before him a seal. With love in his heart he carried two down to the sea which he swam away to go on people. Which he belonged. And all that night she sang from the league knew that. A man of the islands brought a Sea Lady into his home. But he loved her too much to let her go. And he hit her sealskin so that she could not return to the sea.

How. Hot and tired she got baking bread and churning and wishing all the time that she could enter the beauty as coolness of the sea. One day her wee son his two eyes glowing rushed in to tell him about the strange thing he had fallen and the thing softer than the mists to the touch. It was of her own skin. She quickly put it on and went down the path and into the cool water where she swam all during the day. And when evening came she told her son when bowing by Father already in want setting that off this walk and I would throw into a choice. These will make you grow and make the man pleased with himself. And with that. She disappeared with the seed jug into the deep. The legends of the seal people or people of the sea are certainly colorful but

seals are mammals unknown to all in the sounds they make are familiar. One of the quiet fish of the deep to investigate this subject we contacted a noted oceanographer whose field of primary interest is biology and acoustics or bio acoustics. He is Dr. William Cummings of the Navy's undersea research and development center in San Diego. We began our talk with Dr. Cummings by asking him if the science of recording animal sounds underwater is indeed a relatively new a science. Yes it is. I would say it's quite a new undertaking for us to record certainly the sounds of animals in the water. We've recorded sounds of ships underwater for years but it's only been within the last 20 years or so that we've been recording the sounds of animals on the water. We want to know what sounds animals make on the water and why they make their sounds underwater and when they make the sounds

on the water primarily with a view to understanding their behavior and their biology. It would seem to me that there would be at least when you're recording some species that you hadn't recorded before quite a problem in the isolation of that particular sound from the sounds around it. Yes this is probably the most important problem faced by by orchestrations working. At sea. Often when we are going out to sea to record from a particular species always cite a particular species while on an expedition we want to obtain the sounds from that animal and others or we want to get the sounds from the creature that we're reviewing and nothing else in the sea. And of course this means quite a lot of work in many cases never really certain especially during the first recording of a

particular sound whether or not that sound comes from the animal we're observing. And I know of several cases that have been reported in the scientific literature as well as popular literature of sounds that presumably came from a particular species but whose identity was dotted by other investigators after after the Fed. So this is a very very important aspect of our work the way we normally do it is to make repeated observations of a particular species and the sounds produced by that species are what we think of the sounds produced by that species and if this. Correlation is repeated several times and we have some evidence that the sound is from that animal indeed we went on to ask Dr. Cummings about the possibility of some form of meaningful communication between fish and other forms of sea life. The communication we're talking about is a very very simple communication if

it exists at all. These involve very very simple stimuli which in the case of certain fishes is a courtship display merely meant to attract females to an area. In the case of the whales especially the porpoises we know that they have a tremendous called caribou Larry. But we still after studying these things for 15 or 20 years understand very very little about the significance of these sounds. There has been a lot of talk about communicating with porpoises and porpoises communicating with man. To my knowledge there isn't a single bit of evidence. Towards this towards this end. I think that we should point out here just exactly what we think as scientists the purpose of Papias is a doing in many cases and in fact in all cases as far as I know these involve mimicking

Take for example a mynah bird or a parrot. These animals are capable of mimicking the man's voice and they sound very humanoid in their in their. Production of sound certain syllables. I have heard a few tapes that were made of a porpoise type of sounds that were somewhat similar to man's language but in those cases the porpoises were trained to do this. I think that that we have a. Long long way to go before we can show that. That there could be communication between man and porpoises. Do they not have a very keen sense of direction and do they not rely to a considerable extent on something akin to sonar. Oh yes indeed. In fact this is one of the reasons why we study the sounds of porpoises Tom. They have a tremendous

sense of hearing and also of sound production. They rely heavily upon these modes of behavior for their existence in the sea. So we have a great deal to learn. Yes indeed. Dr. Cummings went on to explain how different forms of sea life actually make the sounds that have been recorded. A particular example of invertebrate sound that I mentioned the snapping shrimp is produced by the. Little claws of the animals. They have a pest all like arrangement whereby the. Keeley are snapped together producing the snapping sound. It is almost like one firing a gun pulling the trigger and having the hammer come down on the receiver of the. Overpass. In fact these are often called the pistol shots.

And this by the way is an example of snapping shrimp sound as recorded off San Diego here. And the strokes were recorded at approximately what depth. All these were recorded after San Diego just off the kelp beds and about 80 feet of water. And this is the type of sound that you say is so very common and it's often such a problem when you're trying to isolate some other sound in the same area. Yes indeed it is a problem Tom. Well how does a fish for instance as opposed to a shrimp maker make whatever sound it makes. Well the fish have evolved a number of different methods for producing sound in many cases it involves the so-called gas bladder This is the gas but you see up against the edge of the backbone as you clean a fish with a bowl of.

What is called extrinsic in intrinsic intrinsic musculature and. That actually vibrates the bladder so that the bladder produces the main portion of the of the sound energy. A good example for instance of a gas bladder type of sound is that produced by the toadfish. A good example of playing back sounds to fish is followed by response is the work done at the University of Rhode Island by Dr. James fish. In the next sound that we played back for you you'll hear the responses made by toadfish have been Narragansett Bay to toadfish sounds that were actually played back

into the water through a loudspeaker. The first sound that you hear will be the playback sound followed by the responses. Jim also found that it was possible to suppress calling of toadfish is by playing back a continuous tome will play now a series of 200 cycle per second tomes where there are half second breaks soon. The fish is suppressed so much that it tries to squeeze in its sounds during these breaks. So after the two hundred Hertz tones with the clean breaks you'll hear cases where the fish actually inserted it is

a boat whistle sound. During these half second breaks. Oh. Now what we heard there were 200 cycle tones in between each of the tones was actually the sound of this toadfish is recorded underwater is that correct this right time. That's certainly very interesting project. Yes it is and it was done in the natural environment. Now of course we also of we also record the sounds of whales and playback of these sounds to

other whales in the area. We've often been interested in the effect of predation by whales such as a killer whale on other whales. And the great whale as you know is one that migrates from the Aleutian area all the way down to the low dunes of Mexico to breed each year. And. Roll up in the Aleutians and all the way down to San Diego in fact. It. It. Has been attacked and to be attacked by killer whales and so we thought that we'd like to find out whether or not the grey whale is capable of recognizing the presence of killer whales. By the sound of the killer whale in the runner. And this is an example. In fact this is the the actual sound that we have used this past year playing back into the water in the presence of gray whales This is from the killer whale.

Or her with her. At her what her. That's the sound of a killer whale and you played this back in the presence of grey whales during their migration down the coast of California. What was their response when they heard the sound of a killer whale in the area even though there was no actual killer whale there. Well we. Felt as a result of playing the sound back that they did indeed recognize the presence of a predator

on some of the gray whales are turned around and proceeded northward and others swam into the kelp and others averted the ship by going out to sea as the whales dispersed after hearing the sound of the killer whale did they make any sounds that you picked up on your recording devices. Well we were monitoring the sound production by gray whales at the same time. And we've picked up our low frequency moans but couldn't detect any difference between this type of moaning sound and and produced when sounds are not being played back. Here again a good example of how much we have to learn about the significance of these sounds. They may be very very minor differences in the characteristics of a particular sound that are important as signals to other great whales.

I'm wondering if you've recorded any sounds of fish or other sea life in captivity and if so what they might sound like and what their responses might be. Yes this gives us a wonderful opportunity for singling out the sounds of a particular species a moment ago we were talking about the problem in determining whether or not a particular sound comes from these species we think that it does. And in this particular case where we deal with captive animals we're sure that the only there is only one species in the tank of course we know it's identity are an example of this type of thing which is the work that we're doing on sound production by Garibaldi's know garam body is a very very beautiful orange fish protected by law. From being a spirit caught off California waters and we're interested in its sound production and the significance of a sound production and so this sounds a little strange type of sounds picked up in a captive situation.

You'll hear a thumping type of sound which is a little lower in frequency than the snap type of sound produced by these Garibaldi's as they fed and as they circled one another in a tank. In the in the open sea. Do you find that they should see life. Him it sounds at a particular time of day or is this some level more or less continuous and what has been your experience with recording various forms of sea life at one time. Well yes fish actually produce sound at a particular time of day depending upon the behavior associated with sound production. For instance. Usually during the early morning hours during sunrise and late in the day during sunset.

Most fishes are very active feeders and we have the appearance of several sounds that we believe are associated with feeding during these times of the day. In fact if one looks at. The broad spectrum of sounds produced by a native population of fishes such as that which exists over a. Coral Reef for instance you'll find that sound production actually picks up at sunrise and at sunset and they follow sunrise at Sun and sunset times very very closely within a matter of a minute or a fraction of a minute for instance a particular chorus will start up all and there will peak up. Hearing songs for instance that I recorded when I was working in the Bahamas. We set up a bio Christic station there. Dr. Steinberg on the faculty at the University of Miami at the time

and myself. Set up this station and we had a television set there and we could sit in our comfortable laboratory and actually see fish produce sounds such as these. Nice the sound of a chorus as you called it a fish off the Bahamas. Yes it is. This particular chorus is what we call a sunset chorus. This is composed of the sounds of several different species of coral reef fishes at sunset one of the sea sounds that anyone who's lived near the coast is familiar

with is the sound of the common seal. What if you don't along the line of investigating these sounds. Well we always take the opportunity to record sounds from sea lions Tom. I think that one of the newest undertakings has been an investigation that was long suspected and that is the ability of sea lions to do their barking underwater completely submerged. Now some years ago we had recorded the ruckus barks from Bull sea lions as they protected their harems along the shore along the rocky shores and we picked these up very nicely on the hydrophones and suspected that perhaps some of the sounds might be produced on the water but I think that through association we just couldn't believe that such a sound could be produced when the head was completely submerged and so a number of us had the impression that.

The sound got into the water through a coupling of the chest cavity in the throat with the with the water while the actual mouth was out of the water. These particular sounds Tom were recorded from a hydrophone quite far out to sea. San Diego. Notice how well the barks of the sea lions carry through the water. Crisis sound of sea lions recorded underwater. Yes that's right. This particular sound is made while the bull is near its harem and they are females. It's a territorial type of sound primarily although they do make it at other times. Sea lions make sounds other than the typical barking type of sound.

They do produced produced series of clicks. We don't know for sure whether or not these are used in Echo ranging as purposes use them but certainly it is an echo ranging like sound. These are clicks from sea lions that were recorded off the coast of California. That sound made by the sea lions is one that you speculate might be involved in their echo ranging. Some have speculated this but the work is still under investigation at Stanford Research Institute. What is the future now of your bio acoustic work. What can we look forward to in the coming years and perhaps you'd like to take a step even fry

their head in there. I think that most of our efforts in the future. All well involve just the kinds of problems that we've been talking about today. We want to know why these animals produce sound it's no longer a mystery as to what sounds exist in the ocean we can at any time Flora hydrophone into the water and pick up all sorts of interesting sounds from biological sources. But we want to know why these animals produce the sounds and what just what is the level of their communication. Through continued research and improved techniques and equipment man will no doubt unravel much of the mystery of underwater sounds in the years ahead. But there was a great deal of work to do. The sound you are listening to right now are of unknown origin. What do they mean. What pattern of life do they

explain. More questions for the modern oceanographer to answer as he goes down to the sea. Thanks. Down into the sea is a production of public radio station FM at San Diego State College. On this edition Our guest was Dr. William cumming Violet station with the Navy undersea research and development center in San Diego. Thank you want. To prepare for the program

five. Times. An audio technician also at the undersea center. Thank his programs were written and prepared for broadcast by a Vost atomic menace with the assistance of Ken Kramer traditional music of the sea was arranged and performed by Sam Hinton. And special narrative and poetic passages are read by Cliff Kirk. Production of down to the sea was made possible by a grant from the Corporation for Public Broadcasting. This is the national educational radio network.