Frontiers of Science: To Catch a Fish

To Catch a Fish

Fishing has always been an important occupation for much of mankind. In fact, several of the Lord’s first apostles were fishermen. Jesus Himself was quite familiar with the ways of the sea. Remember when Christ first met Simon Peter and James and John, the sons of Zebedee? He instructed them to launch out into deep water and let down their nets. The astonished fishermen, who had toiled all night and had caught nothing, obeyed and soon had such a multitude of fish entrapped that their nets began to break. Calling for help to their partners in another ship, they were finally able to get the catch on board; but it was so huge that the two ships actually began to sink!

How did Jesus know where to find such great quantities of fish?

That is a question that a lot of us would like to know the answer to. Scientists also are searching for the answer to such a strange phenomenon. To find out what they are learning, two of my sons and I took a trip to Scripps Institution of Oceanography last March. While visiting the aquarium there, we picked up a pamphlet that listed the times of high and low tides for the area around San Diego. Sandwiched in the center of the booklet was an article called “The Grunion Story.” It described the strange habits of a small silvery fish called the grunion that beaches itself upon the sand in very large numbers about twice each month at certain times of the year. These “runs,” as they are called, can be predicted fairly accurately from a knowledge of the tides. The booklet indicated that a grunion run was expected to begin about one o’clock the following morning. Well, you can probably guess what happened when my boys read that!

In the dead of night, Keith’s wristwatch alarm rang to wake us up. We got dressed and headed outside, where we were greeted by a fog so thick that we could only see a few feet in front of us. Undaunted, we climbed into our car and inched our way down the winding street to the ocean’s edge.

Except for us and a couple of sleepy-looking birds, the beach was deserted. Where is everyone? we wondered. We watched wave after wave roll in and break upon the sand and then recede, but no grunion appeared. I stood watch on a rock a little farther out, where a large wave broke over my feet and filled my shoes with water. But still no grunion. After an hour of fruitless waiting, we gave up and wended our way through the heavy fog back to the motel, where we lapsed into sleep.

Suddenly Keith’s alarm rang again, and we saw that it was light outside. It was almost time for the aquarium to open, so we hustled off without eating breakfast. When we got there, however, the aquarium was still closed. Puzzled, we peered through the glass door to see a large clock on the wall with its big hand on six and its little hand between seven and eight. Keith’s watch also had its big hand on six, but its little hand was between eight and nine. Then we realized the reason for the absence of people and grunion at the beach that night. Keith’s watch was an hour fast. We had arrived an hour early and left just before the grunion run was supposed to start!

Our trip was not entirely in vain, however, for we did discover some interesting ways that scientists are using to find fish. One that is truly out of this world employs satellites circling the globe. Some of these satellites have instruments on board that can detect areas of high chlorophyll content in the water. Such pigment concentrations are due to great masses of algae, among which fish often gather to feed. Other satellites have sensors capable of detecting water surface temperatures. Wherever cold regions are spotted in the midst of larger warm areas, scientists can be fairly certain that there is an area of upwelling or a flow of colder water from the depths of the sea that brings important nutrients with it to the surface. Such an area is a place where large fish and their smaller prey are likely to congregate. Still other satellite sensors can detect the presence of giant kelp beds where many sport fish are apt to be found.

All of this information is collected daily at the Scripps Remote Sensing Facility by a giant antenna that communicates with the satellites as they pass overhead. After the data are analyzed, the pertinent information is sent out to anchovy and tuna fleets off the coasts of California and Alaska as part of a large experiment to evaluate the effectiveness of this information. Scientists still do not know how the Savior could find so many fish, but they can surely do a better job of finding them than we did with the grunion!

[illustrations] Illustrated by Doug Roy

[photo] 1. The pier at Scripps where we tried to capture grunion the night before. (Photo by the Sherwood B. Idso.)

[photo] 2. All we had to show for our efforts was a mass of beached kelp. (Photo by the Sherwood B. Idso.)

[photo] 3. A scientist works in the computer room where information received from the satellites is stored and analyzed. (Scripps Institution of Oceanography photo.)

[photo] 4. The large antenna used by Scripps Remote Sensing Facility to receive data from orbiting spacecraft. (SIO photo.)

[photo] 5. A time exposure showing the Scripps antenna scanning the night sky to receive signals from space. (SIO photo.)

[photo] 6. A picture of sea surface waves obtained by radar on the Seasat satellite. (SIO photo.)

[photo] 7. A picture of sea surface temperatures off the coast of California. (SIO photo.)