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determination of oceanic pelagic fishes: tunas, billfishes, and sharks. U.S. Dept. of Commerce, NOAA Tech.

Rep. NMFS 8.
Orange, C. J., and B. D. Fink. 1963. Migration of a tagged bluefin tuna across the Pacific Ocean. Calif. Fish and

Came, 49(4):307-309.
Rivas, L. R. 1975. Variation in sex ratio, size differences between sexes, and change in size and age composition

in western north Atlantic bluefin tuna ( Thunnus thynnus.) Int. Comm. Cons. Atl. Tunas, Coll. Vol. Sci. Pap.,

5(2):297-301.
Yamanaka, H., et al. 1963. Synopsis of biological data on kuromaguro Thunnus orientalis (Temminck and

Schlegel) 1842 (Pacific Ocean). FAO, Fish. Rep., 6(2):180-217.
Yukinawa, M., and Y. Yabuta. 1967. Age and growth of the bluefin tuna Thunnus thynnus (Liinnaeus) in the North

Pacific Ocean. Rep. Nankai Reg. Fish. Res. Lab. 25:1-18.

— Terry J. Foreman, Inter-American Tropical Tuna Commission, c/o Scripps
Institution of Oceanography, La jolla, California 92093, and Yoshio Ishizuka,
National Research Institute of Far Seas Fisheries, Shimizu, Japan. Accepted for
publication May 1990.



NOTES 187

BOBCAT ELECTROCUTIONS ON POWERLINES

Powerline electrocution of birds has been well documented in the scientific
literature (Anderson 1933, Dilger 1954, Harrison 1963, Boeker and Nickerson
1975, Kothman and Litton 1975, Switzer 1977, Pomeroy 1978, Benson 1981,
Olendorff et al. 1981, Dedon and Colson 1987, Williams and Colson 1989).
However, published accounts of electrocutions of other vertebrate taxa are
extremely rare. Edison Electric Institute (1980) noted that snakes, mice, tree
squirrels, Sciurus spp.; flying squirrels Glaucomys spp.; raccoons;, Procyon
lotor, and black bears, Ursus americanus; occasionally come in contact with
energized electrical equipment and, therefore, are subject to potential electro-
cution. Among wild mammals, squirrels are the most frequent victims of
electrocution because of their penchant for chewing on energized wires
(Commonwealth Edison 1975, Pacific Gas and Electric Company [PG&E]
unpubl. data). There is some evidence that interactions between black bears
and power lines are increasing in number as civilization encroaches on the
species' habitat. In Albuquerque, New Mexico, for example, a tranquilized
black bear that had climbed a power pole to escape capture suffered a non-fatal
electrical burn as it fell into a 7,200-volt powerline (W. R. Pilz, Public Service
Company of New Mexico, pers. comm.). To my knowledge, powerline
electrocutions have not been reported in the literature for any other mammalian
species. This note documents the electrocution of two bobcats. Fells rufus, on
PG&E power poles in north-coastal California.

The carcass of an adult female bobcat was discovered by a PG&E line crew
on 19 September 1988, approximately 8.5 km northwest of Inverness, at Point
Reyes National Seashore. The animal was draped over a transformer attached
to a pole supporting a 12,000-volt powerline (Figure 1). Maggots had infested
the carcass, suggesting that the animal had died several days prior to being
discovered. PG&E linemen reported that a similar bobcat electrocution oc-
curred in the late-1970s, approximately 16 km southwest of Inverness, near the
Point Reyes Light Station. However, no additional details are available on this
earlier mortality.

Bobcat electrocution appears to be an extremely unusual and random event,
as evidenced by the absence of published accounts of powerline interactions.
These animals often climb trees when threatened, or occasionally while hunting
(Chapman and Feldhamer 1982). Where trees are absent, as in the coastal
scrub habitat covering much of Point Reyes National Seashore, it is reasonable
to assume that bobcats will climb utility poles to escape danger or pursue prey.
I speculate that the animals in question may have climbed power poles to
escape the pursuit of dogs originating from the local ranches. This behavior
would be consistent with the well-documented "treeing" response displayed
by bobcats and other felids when pursued by trained hunting dogs. After an
animal climbs a power pole, simultaneous contact with two energized wires or
a wire and a grounded object (e.g., a transformer) would normally be sufficient
to cause a "flashover" of electricity and electrocution of the animal.

I gratefully acknowledge W. Crawley, T. j. McMorrow, and B. E. Perron for
providing background information on the bobcat electrocutions. E. W. Colson,
M. F. Dedon, T. Silver, and B. F. Waters reviewed the manuscript.



188



CALIFORNIA FISH AND CAME




FIGURE 1. Carcass of an adult female bobcat on a 12,000-volt powerline transformer.

LITERATURE CITED

Anderson, A. H. 1933. Electrocution of purple martins. Condor, 35:204,

Benson, P. C. 1981. Large raptor electrocution and power pole utilization: a study in six western states. Raptor

Res., 14:125-126.
Boeker, E. L., and P. R. Nickerson. 1975. Raptor electrocutions. Wildl. Soc. Bull., 3:79-81.
Chapman, |. A., and G. A. Feldhamer. 1982. Wild mammals of Nortfi America. The John Hopkins Univ. Press,

Baltimore MD. 1147 p.
Commonwealth Edison. 1975. Chewing squirrels foiled at Commonwealth Edison. Public LJtilities Fortnightly, Sept.

11, p. 90.
Dedon, M, F., and E. W. Colson. Investigation of bird-caused outages in the Pacific Gas and Electric Company

service area. Pages 34-45 in W. R. Byrnes and H. A. Holt, eds. Proc. fourth symposium on environmental

concerns in rights-of-way management. Purdue Univ., West Lafayette, Ind.
Dilger, W. C. 1954. Electrocution of parakeets at Agra, India. Condor, 56(2):102-103.
Edison Electric Institute. 1980. Compatibility of fish, wildlife, and floral resources with electric power facilities.

Edison Electr. Inst., Washington, DC. 130 p.
Harrison, J. 1963. Heavy mortality of mute swans from electrocution. Wildfowl Trust Ann. Rep. 14:164-165.



NOTES 189

Kothman, C. H., and C. W. Litton. 1975. Utilization of man-made roosts by turkey in west Texas. Pages 159-163
in K. Halls, ed. Proc. of the third national wild turkey symposium.

Olendorff, R. R., A. D. Miller, and R. N. Lehman. 1981. Suggested practices for raptor protection on power lines;

the state of the art in 1981. Raptor Res., Rep. 4. Ill p.
Pomeroy, D. E. 1978. The biology of Marabou storks in Uganda; II. Breeding biology and general review. Ardea,

66:1-23.

Switzer, F. 1977. Saskatchewan Power's experience. Blue lay, 35:259-260.

Williams, R. D., and E. W. Colson. 1989. Raptor associations with linear rights-of-way. Pages 173-192 in Proc.
western raptor management symposium and workshop. Natl. Wildl. Fed., Washington, D.C.

— Richard D. Williams, Technical and Ecological Services, Pacific Cas and
Electric Company, 3400 Crow Canyon Rd., San Ramon, CA 94583. Ac-
cepted for publication June 1990.



190 CALIFORNIA FISH AND CAME

BOOK REVIEWS

MARINE POPULATIONS: AN ESSAY ON POPULATION REGULATION AND SPECIATION

by Michael Sinclair. 1988. University of Washington Press, Seattle, WA. 260 p. $25.00 cloth,
$15.00 paper.

The oceans are a highly dynamic environment. Anyone who has studied planktonic life forms
sooner or later is confronted with the question of "How do these organisms maintain populations
in regions that are conducive to their life history?" Plankton are subjected to currents transporting
them from areas optimal for growth and reproduction to areas that may preclude growth, increase
mortality rates, and not allow for recruitment of these organisms or their progeny back to the
originating population. This question not only relates to phytoplankton and invertebrate zooplank-
ton, but to fishes that have a planktonic life stage. It is this question and its implications that the
author examines in this book.

We know a good amount about the life history of Atlantic herring and the author uses these
populations to show that self-sustaining populations exist in areas of the ocean in which ocean
dynamics can be used to ensure that some portion of the planktonic larval stages will recruit back
to the originating population. In response to ocean dynamics, populations of herring have spawning
periods timed to take advantage of seasonal changes in currents, spawning in the proximity of bays
and estuaries, or the migration of spawning adults to areas in which larval stages will have maximal
survival to a size at which they are capable of returning to the spawning areas. Those that are
carried to regions from which they cannot contribute to the population are lost from the gene pool.

Following this analysis, the author defines the "member/vagrant hypothesis". This hypothesis
leads to several tenants. Populations (which have a planktonic life stage) are found in
"geographical settings . . . within which the species' life cycle is capable of closure". Population
size for the most part is limited by the geographical area that allows for closure — those animals
spawned outside of the area (or time period) are lost to the population. For such organisms food
may seldom be a limiting factor. Likewise intraspecific competition may seldom come into effect.
Recruitment success or failure becomes primarily a function of ocean dynamics. A weakening of
currents may result in high recruitment despite lower productivity because more larvae remain in
the geographical area that allows closure. Conversely stronger currents with higher net productivity
may increase larval survival but if most of these are carried away never to recruit back to the
population we have recruitment failure. Once populations become limited to specific geographical
areas by ocean dynamics, a mechanism for speciation becomes apparent. We now have isolated
spawning groups.

The author goes on with further examples of populations, both fishes and invertebrates, in which
the hypothesis is apparently working. The more I read, the more excited I became. In the last
several chapters, the author questions a number of ecological generalizations (food is a limiting
factor, etc). Likewise certain aspects of evolutionary theory, primarily that populations are
self-regulating and therefore competition is a strong factor in natural selection, are not applicable
to animals whose populations are controlled by ocean dynamics.

If any of these statements pique your curiousity, by all means read this book. I hope that the
arguments put forth here are given serious thought. All too often we tend to sit back and assume
an understanding of phenomena because a theory exists or a simple explanation is given, i.e., that
factor is density dependent, when in fact we do not really know the underlying relationships.
Perhaps this is why a number of fisheries today are in trouble. If many of our pelagic fisheries are
limited by ocean dynamics, then it comes as no surprise that our population dynamics models have
not served us well.

The next question then becomes "What do we do now?" Hopefully this work will lead to
advances in fishery management as well as a re-examining of ecological and evolutionary
mechanisms when the old explanations fail. I would hope that anyone interested in population
dynamics and certainly students now taking such courses would read this book.

— John j. Geibel

BATTLING THE INLAND SEA: American Culture, Public Policy, & the Sacramento Valley,

1850-1986

By Robert Kelley. 1989. University of California Press, Berkeley, CA, 416 p., $35.00

This book presents an excellent history of flood control efforts in the Sacramento valley primarily
from the 1850's through 1920, when the present flood control system had been adopted and its



BOOK REVIEWS igi

implementation was well underway. Events from 1920 through the flood of 1986 are described
briefly. The author describes the interrelationships between flood control, swampland reclamation
and hydraulic mining. It is a story of repeated failures but eventually largely successful conclusion,
as the largest flood of record was contained with minimal harm.

The author is a historian, and an important feature of the book is how he has interwoven flood
control activities with the underlying social and political events. Among the latter is the evolution
from a constitutional requirement that governmental actions be prescribed in detail in law to the
acceptance of laws delegating considerable discretion to the executive branch to act within broad
policy. Also of interest, are the shifts back and forth between populist driven local control and
centralized professional management, depending primarily on whether the Democrats or Repub-
licans controlled government.

In the Preface the author acknowledged that reclamation of the valley "ended in the destroying
of a large natural environment". He, however, makes no attempt to describe the resources which
were lost. Nevertheless, those interested in the evolution of our present society in the Sacramento
valley will find the book worth reading.

— Harold K. Chadwick

ARIZONA GAME BIRDS

By David E. Brown. 1989. The University of Arizona Press, Tucson, AZ. 307 p., illustrated.

$19.95 cloth.

I have been an avid consumer of information about upland game birds for over twenty years, as
both a hunter and researcher. Unfortunately, good books about western upland game birds have
been few and far between. I am most pleased to report that this is a good one and will no doubt
become a standard for personal libraries.

The author uses his experience as a wildlife manager with the Arizona Department of Came and
Fish, a naturalist, and a hunter to provide the reader with an informed and insightful treatment of
Arizona game birds. Each chapter covers the distribution, habitat, life history, management history,
population dynamics, and hunting of one of the thirteen game birds. The material is detailed enough
to be of value to the professional, yet not so detailed as to be laborious to read. The text is well
referenced, although the literature is only effectively cited up to 1985. However, it still provides an
efficient and easy way to enter the scientific literature. The book was interesting to read and I
recommend it highly.

— Sonke Mastrup



192 CALIFORNIA FISH AND CAME

MISCELLANEA

The following excerpts are from early issues of California Fish and Game:



Forests, water power, and wild game are three of California's greatest resources. They are ours
to use but not destroy.

— from cover of Volume I, Number 7 — October 1914



The writer has been observing the fisheries of southern California for nearly thirty years. In that
time the supply has dropped off to a menacing extent, due to lack of laws, lack of protection, and
over-fishing where fishes should be protected.

— Charles Frederick Holder, Volume 1, Number 1 — October 1914



Students of natural history have become fully aware that as the country is settled marked changes
take place in its bird life. A few of our species, such as the linnet and mockingbird, have become
more numerous than they were in the early days. But many more have become noticeably scarcer;
some have disappeared altogether. Bird life as a whole has diminished in quantity to an alarming
degree.

— Joseph Grinnell, Volume 1, Number 1 — October 1914



Everyone owns a share in the natural resources of this state. The protection and conservation of
game is, therefore, to the interest of every citizen.

— /-/. C Bryant, Volume 1, Number 3— April 1915



Only a little study of the conservation situation in America is sufficient to show we have allowed
certain parties at interest to take more than their rightful share of the resources of wild nature which
as a matter of simple justice belong, not only to all the people now living, but also to the generations
of the future indefinitely.

—W. P. Taylor, Volume 1, Number 4— July 1915



Two sea otters were seen basking in the sun in the kelp beds off Del Monte wharf on October
22, 1916. They were apparently an old and young one, and the theory is that the old one came back
to look for one of her young which was caught in a sea bass net last year.

—P. H. Oyer, Volume 3, Number 2— April 1917



The sea urchin, which is quite abundant on our coast, will some day be an article of economic
importance. A few are gathered and the meat eaten by Japanese in California and by natives in
Alaska.

— John N. Cobb, Volume 3, Number 3 — July 1917



INSTRUCTIONS TO AUTHORS

EDITORIAL POLICY

California Fish and Game is a technical, professional, and educational journal
devoted to the conservation and understanding of fish and v/ildlife. Original manu-
scripts submitted for consideration should deal with the California flora and fauna
or provide information of direct interest and benefit to California researchers and
managers. Authors should submit the original manuscript plus two copies, including
tables and figures.

MANUSCRIPTS: Authors should refer to the CBE Style Manual (Fifth Edition) and
a recent issue of California Fish and Game for general guidance in preparing their
manuscripts. Some major points are given below.

1. Typing — All text submitted, including headings, footnotes, and literature cited
must be typewritten doublespaced, on white paper. Papers shorter than 10
typewritten pages, including tables, should follow the format for notes. Letter
quality computer print-out is acceptable.

2. Citations — All citations should follow the name-and-year system. The "library
style" is used in listing literature cited.

3. Abstracts — Every article must be introduced by a concise abstract. Indent the
abstract at each margin to identify it.

4. Abbreviations and numerals — Use approved abbreviations as listed in the CBE
Style Manual. In ail other cases spell out the entire word.

TABLES: Each table should be typewritten with the heading margin left justified.
Tables should be numbered consecutively beginning with "1" and placed together
in the manuscript following the Literature Cited section. Do not double space tables.
See a recent issue of California Fish and Game for format.

FIGURES: Consider proportions of figures in relation to the page size of California
Fish and Game. The usable printed page is 1 17 by 191 mm (4.6 by 7.5 in.). This must
be considered in planning a full page figure, for the figure with its caption cannot
exceed these limits. Photographs should be submitted on glossy paper with strong
contrasts. All figures should be identified with the author's name in the upper left
corner and the figure numbers in the upper right corner. Markings on figures should
be made with a blue china marking pencil. Figure captions must be typed on a
separate sheet headed by the title of the paper and the author's name.

PROOF: Galley proof will be sent to authors approximately 60 days before publi-
cation. The author has the ultimate responsibility for the content of the paper and
is expected to check the galley proof carefully.

PAGE CHARGES AND REPRINTS: All authors will be charged $35 per printed page
and will be billed before publication of manuscripts. Reprints may be ordered
through the editor at the time the proof is submitted. Authors will receive a reprint
charge schedule along with the galley proof.



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Online LibraryCalifornia. Dept. of Fish and GameCalifornia fish and game (Volume 76, no.3) → online text (page 7 of 7)