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Whale Primer With Special Attention to the California Gray Whale

Whale Primer
With Special Attention to the California Gray Whale
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Title: Whale Primer With Special Attention to the California Gray Whale
Release Date: 2019-01-15
Type book: Text
Copyright Status: Public domain in the USA.
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Whale Primer: With Special Attention to the California Gray Whale
NATIONAL PARK SERVICE

WHALE PRIMER

With Special Attention to
THE CALIFORNIA GRAY WHALE

by
Theodore J. Walker

Published by
the
Cabrillo Historical
Association
1962

National Park Service, Department of the Interior

Produced in cooperation
with the National
Park Service

Copyright© Cabrillo Historical Association
1962

Second Printing 1965
Third Printing 1967
Fourth Printing 1969

Contents

INTRODUCTION 1
TWO GENERAL MIGRATION ROUTES 2
WHALE WATERS—SUMMER AND WINTER 5
FEEDING—FILTER WHALES 6
EVOLUTION OF WHALES 10
Breathing Adaptations 10
Swimming Adaptations 11
WHALE TYPES 15
Porpoises and Dolphins 15
Squid Eaters 18
Filter Whales 18
SIGNIFICANCE OF BLUBBER 19
Heat Conservation 19
Buoyancy 20
Food Storage 20
SEXUAL MATURITY 21
LIFE SPAN 21
WHALE INTELLIGENCE 23
WHALE SENSES 23
Sight 23
Hearing 23
Smell 24
HABITS 24
ENEMIES 25
Killer Whales 25
Parasites 25
WHALE ABNORMALITIES 26
INADEQUATE KNOWLEDGE OF WHALES 26
CALIFORNIA GRAY WHALE 28
Evolutionary Place 28
Geographic Distribution 29
Shore Habits 30
Scientific Description 31
Reaction to Whaling 33
How Do They Sleep? 33
Migration Groupings 34
Breaching 35
WHALING 36
Whalers As Explorers 37
Prehistoric Whaling 37
Historic Whaling 39
Modern Whaling 42
EXAMPLE OF UNREGULATED WHALING 47
California Gray Whale 47
GRAY WHALE PROTECTED 48
VALUE OF GRAY WHALE 48
Esthetic 48
Scientific 49
Commercial 49
NATURAL POPULATION CONTROLS 51
CURRENT SCIENTIFIC INQUIRY 52
Life Expectancy 52
Age Determination 52
Distribution and Population Rise 53
APPENDIX 55

Migration routes of the California gray whale. The Korean herd may now be extinct.

1

Introduction

The WHALE PRIMER provides a brief introduction to one of nature’smost interesting creations, the whale. The principal star of the handbookis the California gray whale which in recent years has become a majortourist attraction in southern California. Notwithstanding the extremeinterest, no concise interpretation of the migration has been prepared.Although there is a tremendous number of technical and popular writingsabout whales, there is still great mystery about them. Whales carry onpractically their entire lives below the surface of the sea out of reach ofman, so that most of our knowledge has been pieced together from thestudy of the bodies of slaughtered whales. The literature abounds in partialtruths, misinterpretations and technicalities which confuse even thespecialists. Many of the sources of information require translation.

Furthermore, many of these papers were published in journals of limiteddistribution. Others are long since out of print, and much of the primaryhistoric records can be found by examination of records which exist onlyin one particular library. In the preparation of this manuscript, hundredsof books and over 4,000 papers were catalogued, of which the most importantwere available, and examined. The author was particularly fortunateto have Japanese and Russian friends who gave gladly of their timeto insure coverage of these important papers.

The author deliberately made an extreme condensation of the facts inorder to prevent the reader from being overwhelmed by details that merelyobscure the broad picture. It is hoped that the reader will gain an awarenessof the extreme mastery by whales of the marine environment. Otherbasic concepts of biology, which are clearly illustrated by the natural historyof whales, are developed.

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The intense interest and pleasure which the sight of the migrating whalecreates clearly overshadows the brief monetary benefit that the whalingindustry might gain from slaughtering it. We hope that you will be stimulatedto join forces with those of us who feel that man should preservethose forms of life which add so much interest, beauty, and knowledge toman’s awareness.

Two General Migration Routes

The migration of the California gray whale is one of the most remarkablenatural history events in the world today. The majority of thesewhales journey southward just off the shore of southern California andLower California during January and February. Although a few earlymigrants may pass San Diego early in December, they are not abundantuntil Christmas. An occasional straggler can be sighted in March.

Only 20 years ago this species was so rare, that little hope was held thatit could ever recover. Today the species appears out of danger, thanks tointernational cooperation among the whaling nations which stopped theslaughter of this truly unique whale. Now it is not at all unusual to seebetween 50 and 75 whales a day during the peak of the migration.

One of the finest locations for viewing this migration is the CabrilloNational Monument which commands an almost aerial view of the coastline.Here individual whales can be watched for at least 1 hour, as theyhove into view from the north and at last recede to the southeast alongthe Silver Strand. The first and only public observatory for whales wasestablished at the monument in 1951. The naturalist on duty not onlykeeps a plot of the whales passing by, but also helps visitors find their firstwhale. The observatory is one of the most popular wintertime attractionsin southern California. With so many pairs of eyes on hand, it is not surprisingthat the count of whales is remarkably complete. There is no othermarine animal which can be seen with such certainty in its naturalelement.

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Migrating gray whales off Point Loma, Calif. Photograph by Burky Reeves.

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Migrating gray whale passing San Diego, Calif. Courtesy Scripps Institute of Oceanography.

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Migrating animals have always fascinated man who considered themharbingers of the seasons. Man continues to puzzle over the mysteries ofhow these animals are able to navigate so precisely and how they are ableto maintain such timetables. Whereas other migrating animals pass broadlythrough an area, the California gray whales, at least on the final part ofthe route, are passing along just outside the surf zone, virtually single file!It is hard to realize that 3 months earlier these whales started off fromtheir summer quarters in the Arctic Ocean and the Bering Sea, as well asalong the shore of Siberia and Kamchatka en route to their winter quartersin the lagoons and harbors along the outer coast of Lower California. Betweenthese two areas lie 6,000 miles of seemingly trackless ocean. Withthe advent of spring the whales must be on their way back again to theirsummer grounds.

Although all the large whales make such extensive travels, except thebowhead, only the gray whale spends so much time in sight of land. Theother species are truly oceanic at all times, and never seem abundant becauseof the vastness of the oceans. Like the gray whale they congregatein polar seas during the summer months, moving into temperate and subtropicalwaters for the winter months. To this day, much of the migrationroute is unknown. Perhaps some day a scientist will attempt to trail agroup of whales along the entire route. The tendency of the gray whale tohug the coast is manifest only within 600 miles of the destination. Thismay be a precautionary routing which prevents the whales from makingtheir landfall south of the lagoons. Such an error in navigation would notonly prolong the migration, but leave the whales on the horns of adilemma—to swim on south or turn back?

Whale Waters—Summer and Winter

One cannot help but be impressed with the remarkable utilization oftime by the whales whose lives seem to be divided into two principal seasons,a summer feeding period and a winter period of reproduction. Eachof these major activities is preceded by a tremendously long migration.Nearly half of every year must be devoted to this activity. Considering theextreme length of the migration, whales cannot wander aimlessly or carelessly.Whales which summer in the Antarctic continue to do so as do thewhales in the Arctic waters, and only rarely does one pass through the widebelt of equatorial water to venture into the other hemisphere.

Once on the summer grounds the whales occupy themselves with feedingalmost continuously during the long polar day. Even though the foodis patchy, the whales seem to find it quickly, spending a minimum of timein search. By the onset of autumn, they are fat, and all the babies areweaned.

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It is uncanny that the various species all manifest the instinctive reactionto vacate this region at the proper time, thus avoiding almost certaindeath by the freezing of the sea’s surface. Again the seeming miracle ofaptness is evident, for the whales swim unerringly out of the dangerousareas toward warmer and calmer seas. Because of the extremely wide bandof winter storms, whales must move at least below 30° latitude to be clearof the areas of stormy seas. Migration stops as soon as they are sufficientlyclear of these. Whales then undertake the other essential link in the chainof life, reproduction. By spring the babies are strong enough and fatenough to accompany their mothers.

Feeding—Filter Whales

Whales do not feed extensively while migrating. For the most partthere is not time enough, nor is the food plentiful enough to make itworth the effort. However, in the polar seas the whale’s food is plentifulenough to discolor the water. On close examination, the discolorationproves to be caused by thousands of tiny shrimps which are very slenderand less than one-half inch in length. These creatures congregate inswarms near the surface to feed on microscopic plants known as diatoms.The whales need only swim back and forth through these cloudlike aggregationsto fill their mouths quickly with water and shrimp. With eachmouthful, the water is expelled between the jaws through a mat of fiberswhich hangs down from the upper jaw. The shrimps, which are retainedon the mat, fall down onto the tongue and are swallowed. The work ofpushing out several tons of water with each feeding is done by the tremendoustongue.

The fiber mats are the frayed inner side of enormous hornlike plateswhich grow down from the palate. The main body of each plate is placededgewise to the outgoing water so that many plates are required to completethe mat which runs from the tip of the jaw to the corner of themouth. These plates vary in size and stiffness from species to species. Someof the plates from the mouth of the bowhead whale are 12-14 feet inlength, whereas in the finback whale the plates are 2-4 feet. There can beover 200 plates per side in the filtering structure. The frayed inner edge7is constantly breaking off and the plates keep growing and fraying toprovide the necessary thickness for the mat. Technically, these plates arecalled baleen. They were called whalebone by the whalers, and that is thename which is still used in commerce. The plates have no relationship tobones, nor could they be mistaken for them. The whalebone was assiduouslycollected and sold to be made into a variety of objects such as umbrellastays, corset stays, buggy whips and other articles which today are madeof steel or plastic. There was a great demand for the product and a bowheadwhale produced over a ton and one-half of whalebone valued backin the 17th century at over 400 English pounds, equivalent to about$10,000 today.

It has been observed that the coarseness and thickness of the baleen issuited to the size of the food which is filtered. For example, the rorqual orSei whale, which feeds on tiny shrimp species, has a filtering surface whichresembles fine wool. The blue whale, which feeds on the largest of shrimpsand on fish, has the coarsest filter. Generally, fish occur only in the dietsof the blue, finback and other rorqual which swim fast enough to engulfthem. Here, the fish are weak-swimming, schooling fishes. The gray whale,unlike the other filter feeders, feeds on bottom-frequenting crustaceansknown technically as amphipods. These organisms, occurring principallyin shallow water, keep the gray whales close to the shores of Siberia andKamchatka.

In order for a whale to be able to exist on a 3 to 4 month feeding period,it must have not only ample food, but time in which to collect it. Althoughthe whales may not all be far enough north to have a 24-hour day, thereis enough twilight to let them feed the clock around. In order to take advantageof the prodigious amounts of food available, whales have a hugefour-chambered stomach. It

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