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California Fish and Gany is a journal devoted to the conservation of wild-
life. If its contents are reproduced elsewhere, the authors and the California
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Please direct correspondence toi

Robson A. Collins, Editor
California Fish and Gam9
350 Golden Shore
Long Beach, California 90802






Published Quarterly by






CLAIRE T. DEDRICK, Secretary for Resources

BERGER C. BENSON, President, San Mateo


''*^"''°l« Son Francisco *

Los Angeles Cordiff-by-the-Seo ^


E. C. FULLERTON, Director

1416 9th Street

Sacramento 95814


Editorial Staff


ROBSON A. COLLINS, Editor-in-Chief Long Beach <,

KENNETH A. HASHAGEN, Editor for Inland Fisheries Sacramento

CAROL M. FERREL, Editor for Wildlife Sacramento

ROBERT N. TASTO, Editor for Marine Resources Menio Park

STEVEN N. TAYLOR, Editor for Salmon and Steelheod SocramentOi.

HAROLD K. CHADWICK, Editor for Striped Boss, Sturgeon, and Shad Stockton






The Status of Brown Pelicans at Anacapa Island in 1975

Daniel W. Anderson, Ronald M. Jurek and James O. Keith 4

Supplemental data on the food habits of the
Western Cray Squirrel Walter E. Stienecker 11

Effects of Salinity on Larval Growth in the California Killifish, Fundulus

parvipinnis Cirard Teegavarapu R. Rao 22

Detection of Delayed Annulus Formation Among Bluegill Tepomis
macrochirus, Populations at Lake Nacimiento, California

Delores Brown, Edward E. Miller and C. E. von Geldern Jr. 29

'Stomach Contents of Northern California Dungeness Crabs, Cancer

r magister. Daniel W. Gotshall 43

Reactions of Fish Red Blood Cells with Mucus and Sera

* from Other Fish(es) Albert C. Smith 52


Extension of Red Fox Distribution in California Randall L. Gray 58

Acorn Selection by Band-Tailed Pigeons

Michael E. Fry and Charles E. Vaughn 59

Alabama Spotted Bass grow at Record Rate in Lake Perris, California

Delores Brown, Kenneth Aasen and C. E. von Geldern, Jr. 60

Birth of a California Sea Lion on Southeast Farallon Island

Raymond J. Prerotti, David G. Ainley and T. James Lewis 64

Observations on the Breeding Behavior of the Harbor Seal in
'' Humboldt Bay, California Peter M. Knudtson 66

Notes on Some Fishes Collected off the Outer Coast of
Baja California Glenn F. Black 71






Calif. Fish and Came 63 ( 1 ) : 4- 1 0. 1 977.



U.S. Fish and Wildlife Service

Davis, California


Wildlife Management Branch

California Department of Fish and Game

Sacramento, California



U.S. Fish and Wildlife Service

Federal Center, Denver, Colorado

nif hl« °' "7 °" productivity, chemical residues, and eggshell thickness of Califor- ^
n.a brown pel.cans at Anacapa Island and nearby Santa Cruz island suggest that the
Sir? "* '!.'l'r'"?«^'°'" D?T-'elated reproductive failures. The improved pro! ^
of DDE'a'nn«h °n 'fV""*' • ""^ **''°"«'' ""'• "°^*^^'' P'^H^uctivity, resid'^^ '
o ?q74 ^.aa!^ l* wu""' '" l'^^ ^^'^ "«» significantly different from those i
of 1974 suggesting that the rate of improvement has begun to level off Pelican
productivity is still too low for population stability
Chemicals other than DDE are discussed. PCBs were also found at levels of possi-

ized '" '"*'"°"* ''"" (1%9-72), but recent levels seem to have stabS-

Brown pelican colonies will require continued monitoring for some years to come
We recommend that the California brown pelican be retained on the CalifomU^i ,
2 Z nTll' ^'Tk' "^ ' ^ P'^Hl^ctivity exceeds 1.0 young per nest anempTand
2) the numbers of breedmg adults in California waters begin to increase. >

The status of brown pelicans {Pelecanus occidentalis californicus) in the**
coastal waters of California and just south into Mexico at Islas Los Coronados
through 1974 was reviewed by Anderson et al. (1975) and Anderson and.
Anderson (1976). In 1971, there was enough concern about the brown pelican
population decline in the Channel Islands area to have the subspecies placed on^
California s list of "endangered wildlife" (Leach 1972, 1974). Although brown
foinf 1 ^''*°^'"' V ^f'^f "ested on other islands in California waters (Gress^
1970), Anacapa sland (lat 34»01'N, long 119'26'W) and nearby Scorpion Rock^
off Santa Cruz Island (lat 34»03'N, long 119°33'W) have been the only nesting
Sites used m California waters since our studies were initiated. The California'
nesting population of brown pelicans has been monitored since 1969 by a team
nTpw^^^f^f M^"^ of Fish and Game (DFG), U.S. Fish and Wildlife Service
(USFWS), U^S. National Park Service (USNPS), and University of California •

I I ! '^^""Jl ^'^ °" ^^^ ^^^^"^ °^ P^''^^" colonies on Anacapa and Santa Cruz.
Islands in 1975. Reasons for the decline of Califomia's brown pelicans will not

' Present address: Division of Wildlife and Fisheries Biology, University of California, Davis 95616.


be reviewed here (see Anderson and Anderson 1976). A significant recovery in
pelican productivity (young fledged per nest attempt) began around 1972 (An-
derson et al. 1975). Productivity in 1974 was significantly better than that ob-
served from 1969 to 1973.

', Owing to the extreme severity of the brown pelican problems formerly caused
by DDT pollution, only DDT and metabolites were reported by Anderson et al.
(1975). In this report, we will also discuss other chemical pollutants found in
brown pelican eggs off Southern California.


Colony surveys were conducted throughout the breeding season from a boat

anchored below the colonies by the Department of Fish and Game and U.S.

J National Park Service on 30 March, 10 April, 22 April, 30 April, mid-June, 8

J August, and 8 September. On most occasions, one or more of us were present

i, on these surveys. No entries were made into the nesting area until all young were

of bandable size. After that, when human presence was no longer hazardous (on

8 August and 8 September), the nesting areas were entered and more accurate

productivity data were obtained. Eggshells and addled eggs were collected. We

found no carcasses in 1975. Young were banded and color-marked.

Our methods of chemical analysis for organochlorine residues are cited by
Anderson et al. (1975). Residue analyses reported here were conducted by the
USFWS, Denver Wildlife Research Center, Denver, Colorado. Residues of or-
ganochlorine pollutants are given as ppm lipid-basis. To convert these to a rough
estimate of ppm fresh-weight basis, multiply our values by 0.05.
I Unfortunately, in 1975 we recovered only four intact brown pelican eggs that
'-were suitable for chemical analysis; three of these were dried and putrified.
Stickel et al. (1965) reported exaggeration of egg residues by as much as eight
times in dessicated eggs. Putrefaction apparently does not decompose the or-
ganochlorines (Mulhern and Reichel 1970), although it is essential to adjust
residues for losses of moisture. Incubation and possibly putrefaction apparently
resulted in the loss of some egg lipids in three eggs ( see Romanoff 1 932 ) to about
0.6 of their normal value. Five to 6% lipid content is normal for fresh brown
pelican eggs (D. W. Anderson unpublished). We therefore corrected residues
' in our 1975 sample for lipid and water loss (Stickel et al. 1973) and then
converted them to a lipid-basis, assuming 5% lipids, so that they would be
comparable with previous years' data. Residues of heavy metals were analyzed
by atomic absorption spectrophotometry according to the methods described
- by i. Okuno, Denver Wildlife Research Center.

^ Productivity of Brown Pelicans

At least three periods of nesting activity were apparent during the nesting
• season of 1975 on Anacapa and nearby Santa Cruz. This asynchronous nesting
^ pattern made our surveys more difficult than in previous years, but we are
' confident that out estimates are accurate.

Production on the separate islands was as follows in 1975: Anacapa — 212

nests, 182 young produced; Santa Cruz — 80 nests, 74 young produced. The two

' colonies combined produced 0.88 young per nest attempt. This compares with

^ 0.73 in 1974, 0.14 in 1973, 0.22 in 1972, and 0.007 in the period 1969-71 for the


same colonies (Anderson and Anderson 1976).

Our productivity estimates for 1975 suggest a slight improvement over 1974,
but this was not statistically significant as suggested by the overlap of the 95%
confidence intervals (CIs) of the two estimates (Steel and Torrie 1960): 1975 —
CI = 0.79-1.03, 1974— CI = 0.51-1.05.

Residues in Brown Pelican Eggs
Mean DDE residues in 1975 (ppm lipid-basis) were slightly higher than in
1974 (Table 1), but not significantly so (Wilcoxon two-sample test, P > 0.1,
Sokal and Rohlf 1969:391-394). Eggshell thickness did not differ significantly
between 1974 and 1975 in either intact or broken eggs (Table 1 ).

TABLE 1. Pollutant Residues and Eggshell Thicknesses of Brown Pelican Eggs from Anacapa
island in 1975 Compared with Previous Years' Data from the Same General Area.


Measurements 1969* JWT 7974^ TWT

Chemicals (geometric X, ppm) n = 28 n = 4 n = 39 n = 4

MP'-DDT + M/7'-DDD (lipid-wt.) 54 7 ND ND

M/t'-DDE (lipid-wt.) 853 175 97 113

PCB (lipid-wt.)t 200 43t 146 120

Hexachlorobenzene (lipid-wt.) — — — 0.09

Mercury (wet-wt.) — 0.30 — 0.10

Lead (wet-wt.) — 0.18 — 0.14

Cadmium (wet-wt.) ^ — <0.0S — <0.05

Shell Thickness (arith. X, mm)

Intact eggs, mean ± 95% CI 0.40 0.51 0.48 0.51

±0.02 ±0.07 ±0.02 ±0.04

Intact eggs, sample size 12 4 59 9

Broken eggs, mean ± 95% CI 0.29 0.34 0.38 0.36

±0.02 ±0.03 ±0.03 ±0.06

Broken eggs, sample size 53 26 27 13

* Data on DDT and metabolites are from Anderson et al. (1975). A dash means that the residue was nH

determined, and ND means the chemical was tested for, but not detected. Chemicals are reported for intact

eggs only.
t 1969 PCB residues are from Risebrough (1972) and were quantified on the basis of Arochlor 1254. The 1973-7;"

PCBs were quantified on the basis of Arochlor 1260. Therefore, these residues are not rigorously comparable.

A correction factor of 2.15 (Risebrough and deLappe 1972) was applied to the data, but no statistical test was

X Without one value of 6 ppm, this mean would be 86 ppm.

Residues of PCBs ( polychlorinated biphenyls ) ( Peakall and Lincer 1 970, Dust-
man et al. 1 971 ) , although not associated with eggshell thinning in birds ( Peakall
and Peakall 1973), may be responsible for parental behavior changes observed
in the Anacapa brown pelicans (i.e., reduced nest attentiveness) (Peakall and,
Peakall 1973, Cress 1970). Mean PCB residues (lipid-weight) were around 200
ppm in 93 intact and crushed eggs at Anacapa in 1969 (Risebrough 1972), but
averaged 146 ppm in 1974 and 120 ppm in 1975 (Table 1). Although these
residues were measured by different laboratories, the data suggest that PCBs
may have declined since 1969, but not as dramatically as did DDT and metabo-
lites over the same time period (Anderson etal. 1975) (Figure 1 ). DDE and PCB
residues in eggs appear to have remained essentially unchanged in the last 2'
years, but the possible discrepancies in analyses of PCBs do not allow statistical
testing of the hypothesis of a decline in PCBs since 1969. Young and Szpila


..(1975) have reported a recent decrease in PCBs in mussels {Mytilus califomi-
\\cus) of Southern California; as with pelicans, the decrease in PCBs was less than
I that in DDT compounds.














^ FIGURE 1. Residue changes of DDE and PCB in intact brown pelican eggs from Southern Califor-
nia. The arrow indicates a major drop in environmental input of DDT. According to
published data, major input of DDT ceased in 1970 (Anderson et al. 1975) and by 1971
it had decreased to about 0.5% of previous levels (Jukes 1974, citing the DDT-manu-
facturing company president). There is some disagreement as to the actual levels of
input before 1970 (jukes 1974).

The Other major organochlorine residue found in pelican eggs at Anacapa
.Island wasdieldrin. The mean dieldrin level (lipid-basis) was 1.29 ppm in seven
of the 1973-74 pelican eggs, but less than 1 ppm (the level of analytical sensitiv-
ity) in the other 36. Fourteen additional eggs of normal shell thickness, collected
in 1973 in the Gulf of California (D. W. Anderson USFWS, unpublished data),
"contained a mean of 0.95 ppm dieldrin. No dieldrin was detected above the level
of analytical sensitivity in our small sample of pelican eggs from 1975. Dieldrin
levels were similarly low at Anacapa in 1969, with a mean of 0.98 ppm lipid-basis
for 1 9 eggs in which the chemical was tested ( R. W. Risebrough pers. commun. ) .
This level was judged to be unrelated to eggshell thinning in Anacapa brown
pelicans (Risebrough 1972).

We also conducted a small number of analyses for residues of mercury, lead,
and cadmium (Table 1 ). All of the levels were low, as were those found in
Anacapa eggs in 1971 (Conners et al. 1972) and in 22 eggs collected in the Gulf
of California in 1973 (D. W. Anderson USFWS, unpublished data). Means were:


0.58 ppm Hg, 0.10 ppm Pb, and <0.05 ppm Cd (all residues of metals expressed
on a ppm fresh-weight basis of egg contents). Sell (1975) has reported that
domestic poultry retain little ingested cadmium (4% after 23 days), and that
virtually none is deposited in either the egg yolk or albumin. Therefore, the low
cadmium levels we report here are difficult to evaluate and probably do not truly
reflect exposure. Lead and mercury, like dieldrin, appear to be unrelated to the
past reproductive-eggshell problems of Anacapa's brown pelicans. Cadmium
levels need to be determined from other tissues, but we do not suspect that levels
in the Anacapa area are unusually high (Martin and Broenkow 1975).


Our 1975 data indicate that the improvement in brown pelican productivity
reported in 1974 (Anderson et al. 1975) is continuing, but with the rate of
improvement leveling off. Our data on eggshell thickness and pollutant residues
support this conclusion (Table 1 ). The continued improvement is encouraging,
but it may be that DDE levels have again "stabilized" in the brown pelicans off
Southern California (Figure 1) and that a complete recovery of reproductive
potential is still some years in the future.

DDE is persistent with an unusually long half-time, it accumulates at low
dietary levels, and mobilizes rapidly and at realistically low laboratory doses
(review by Stickel 1975). The eggshell thinning effect of DDE persists, although '
it lessens, at least 1 year, and likely more (W. H. Stickel pers. commun.), after
experimental birds are placed on clean diets (Haegele and Hudson 1974). The
situation off California might be considered as an acute problem becoming a
chronic one.

Apparently, the non-DDT residues examined in brown pelican eggs are either
at low levels or not changing rapidly. Some of these pollutant levels may repre-
sent additional, less acute, and less obvious ecological problems off Southern
California, such as those that might be manifested by low levels of PCBs or
combinations of DDE and PCB (Risebrough and Anderson 1975). These and the
heavy metal residues will be difficult to evaluate ecologically and physiological-

We estimate that current productivity is still 10-30% below what it should be
to maintain long-term population stability, depending on how the data are
interpreted. A "recruitment standard" has been postulated to estimate the
necessary productivity for brown pelicans by Henny (1972) based on a small
sample size of band recoveries for the eastern subspecies. Based on more recent
field studies on productivity (D. W. Anderson and R. W. Schreiber USFWS,
unpublished data, Schreiber 1975) the figure postulated by Henny (1.2 to 1.5)
seems too high.

For example, the populations of brown pelicans in Florida are relatively sta-
tionary (Williams and Martin 1970, Schreiber and Schreiber 1973, Schreiber
1976). One colony on the west coast of Florida has been monitored for 7 years
by R. W. Schreiber (pers. commun.); this colony has produced an average of
about 1.0 young per nest (range = 0.3 to 1.7) from 1969 to 1975 (Schreiber
1975). This colony, colonies on the west coast of Florida, and colonies through-
out Florida have not shown any trend of decline (Schreiber and Schreiber 1 973 ) .
Only long-term studies will reveal what constitutes the average productivity or
recruitment that will interact with mortality and immigration to produce popula-


tion stability or increase in the brown pelican.

Also, as Anderson et al. (1975) pointed out, different proportions of the total
adult pelican population breed from year to year. Thus it becomes difficult to
estimate if a population is increasing or decreasing on the basis of short-term
colony census data. There is no doubt that the population of brown pelicans
breeding off Southern California is currently much smaller than it was prior to
1949 (Anderson and Anderson 1976), and there is no doubt that productivity
has improved since 1971. Recruitment of new breeders from the 1974-75 pro-
duction probably will not be seen until recently-produced pelicans are 3-5 years
old (Anderson and Anderson 1976). Only time will tell if the breeding popula-
tion increases because of the improvement.

Long-term productivity above about one young per nest attempt, coupled
with a sustained increase in the breeding population of brown pelicans off
California, should be the minimum criteria in judging whether to remove brown
pelicans from the State's list of endangered fauna. In conclusion, we recommend
that the brown pelican be retained on the California list of endangered fauna,
since the State's only viable pelican colonies on Anacapa and Santa Cruz are
still not reproducing sufficiently for population stability (Anderson et al. 1975).


Our studies have been coordinated by H. R. Leach (DFG), and we are grateful
for his continuing support. The USNPS, Channel Islands National Monument,
has provided continual aid in the field. W. H. Ehorn and F. Jacot have cooperated
in our research and continually responded to our management recommenda-
tions for Anacapa Island. The USFWS, Denver Wildlife Research Center has also
provided continuous support for brown pelican research on the West Coast. We
are grateful to H. H. Hoover for continuing assistance. R. E. White and the
laboratory at the Denver Wildlife Research Center conducted our chemical
analyses. R. W. Schreiber and W. H. Stickel made valuable comments on the

In 1976, productivity on Anacapa declined to 0.67 young per nest (n-about
4(X) nests). There was no pelican nesting on Santa Cruz in 1976. Visits into the
Anacapa colony were too late to obtain eggshells and addled eggs, but analysis
of two young found dead on the colony (A.L. Bischoff pers. commun.) indicated
low organochlorine residues. The poor 1976 productivity was at least in part due
to a failure as suggested by: 1 ) badly emaciated dead young in the colony, and
2) low numbers of adults in or near the colony on 25 July (19 compared to
around 1,000 in previous years). Young were produced in 1976, but the nesting
season was asynchronous and many young starved on the colony before fledg-
ing. Surveys will continue in 1977. — D.W.A.


Anderson, D. W., and I. T. Anderson. 1976. Distribution and status of brown pelicans in the California Current.
American Birds, 30(1): 3-12.

). R. Jehl, Jr., R. W. Risebrough, L. A. Woods, Jr., L. R. DeWeese, and W. C. Edgecomb. 1975. Brown

pelicans: improved reproduction off the Southern California coast. Science, 190(4216): 806-808.

Conners, P. C, V. C. Anderlini, R. W. Risebrough, J. H. Martin, R. W. Schreiber, and D. W. Anderson. 1972.
Heavy metal concentrations in brown pelicans from Florida and California. Cal-Neva Wildl., 1972: 56-64.


Dustman, E H., L. F. Stickel, L. ) Blus, W. L. Reichel, and S. N. Wiemeyer. 1971 The occurrence and

significance of polychlorinated biphenyls in the environment. N. Amer. Wildl. Nat. Res. Conf., Trans, 36:

Cress, F. 1970. Reproductive status of the California brown pelican in 1970, with notes on breeding biology and

natural history. Calif. Dept. Fish and Came, Wildl. Manage. Br. Admin. Rep., 70-6. 21 p., mimeo.
Haegele, M. A. and R. H. Hudson. 1974. Eggshell thinning and residues in mallards one year after DDE

exposure. Arch. Environ. Contam. Toxicol., 2: 356-363.

Henny, C ). 1972. An analysis of the population dynamics of selected avian species: with special reference to
changes during the modern pesticide era. U.S. Fish Wildl. Serv. Wildl. Res. Rep., 1: 41-46.

jukes, T. H. 1974. Insecticides in health, agriculture, and the environment. Naturwissenschaften, 61: 6-16.

Leach, H. R. 1972. Our endangered wildlife. //?.• At the crossroads: a report on California's endangered and rare
fish and wildlife, January 1972. Calif. Dept. Fish and Came. 99p.

1974. Birds and mammals. In: At the crossroads 1974: a report on California's endangered and rare

fish and wildlife, January 1974. Calif. Dept. Fish and Came. 112p.

Martin, J. H., and W. W. Broenkow. 1975. Cadmium in plankton: elevated concentrations off Baja California.
Science, 190 (4217): 884-885.

Mulhern, B. M., and W. L. Reichel. 1970. The effect of putrefaction of eggs upon residue analysis of DDT and
metabolites. Bull. Environ. Contam. Toxicol., 5(3): 222-225.

Peakall, D. B., and J. L. Lincer. 1970. Polychlorinated biphenyls: another long-life widespread chemical in the
environment. BioScience, 20(17): 958-964.

and M. L. Peakall. 1973. Effect of a polychlorinated biphenyl on the reproduction of artificially and

naturally incubated dove eggs. J. Appl. Ecol., 10(4): 863-868.

Risebrough, R. W. 1972. Effects of environmental pollutants upon animals other than man. Berkeley Symp. on
Math. Statist, and Probability, Proc., 4: 443-464.

, and D. W. Anderson. 1975. Some effects of DDE and PCB on mallards and their eggs. J. Wildl.

Manage., 39(3): 508-513.

and B. deLappe. 1972. Accumulation of polychlorinated biphenyls in ecosytems. Environ. Health

Perspectives, 1(1): 39-45.

Romanoff, A. L. 1932. Fat metabolism of the chick embryo under standard conditions of artificial incubation.
Biological Bull., 52(1): 54-62.

Schreiber, R. W. 1975. Reproductive success of the brown pelican [Pelecanus occidentalis) , Tarpon Key,
Pinellas County, Florida 1969-1975. Proc. 93 Stated Meeting A.O.U.

1976. Brown pelican species account. Florida Comm. on Rare and Endangered Plants and Animals.

, and E. A. Schreiber. 1973. Florida's brown pelican population: Christmas Bird Count Analysis.

American Birds, 27(4): 711-715.

Sell, J. L. 1975. Cadmium and the laying hen: apparent absorption, tissue distribution and virtual absence of
transfer into eggs. Poultry Sci., 54(5): 1674-1678.

Sokal, R. R., and F. J. Rohlf. 1969. Biometry: the principles and practice of statistics in biological research. San

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