Phillips et al Occas Pap 283 reprint

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Occasional Papers
Museum of Texas Tech University Number 283 4 March 2009
Sy S t e m a t i c S o f St e l l e r Se a li o n S (Eu m E t o p i a s j u b a t u s ): Su b S p e c i e S
re c o g n i t i o n ba S e d o n co n c o r d a n c e o f ge n e t i c S a n d mo r p h o m e t r i c S
Ca l e b D. Ph i l l i P s , Jo h n W. bi C k h a m , Jo h n C. Pa t t o n , a n D th o m a s s. Ge l a t t
ab S t r a c t
Previous studies have revealed discontinuities in the distribution of genetic markers that
led to the recognition of eastern, western, and Asian stocks of Steller sea lions (Eumetopias
jubatus). The most profound break separates the eastern and western stocks and is based upon
both nuclear and mitochondrial genetic markers. Here, a morphometric analysis of skulls was
used to re-evaluate geographic variation in light of the genetics data and to possibly identify
characters to distinguish between the eastern and western stocks. For males, three variables
were used in stock assignment to correctly identify 88.13% and 86.59% of individuals from the
eastern and western stocks, respectively. Through the same method the correct identication in
stock assignment using ve selected variables for female eastern and western stock individuals
was 86.27% and 88.1%, respectively. Furthermore, plots from canonical discriminant analyses
clearly separate individuals into stocks with very minimal overlap. Based on the observed mor-
phological differences between these genetically differentiated stocks, we recognize two subspe-
cies of E. jubatus; one includes the Asian and western stocks, and the other the eastern stock.
The vernacular name Loughlin’s northern sea lion is used to signalize the eastern subspecies.
Key words: genetics, morphometrics, Steller sea lions, subspecies, taxonomy
in t r o d u c t i o n
The Steller sea lion, Eumetopias jubatus, ranges
from central California, along the North Pacic Rim
to the Sea of Okhotsk in Russia (Fig. 1; Loughlin et
al. 1987). The observation that the population size of
this species began to seriously decline over the latter
half of the last century (Merrick et al. 1987) led to the
1990 listing of E. jubatus as protected under the U.S.
Endangered Species Act (ESA). Efforts to diagnose
the cause of the decline have produced several pos-
sible explanations, however none unequivocally has
been identied as the chief mediator of the population
reduction and, in reality the decline was likely the result
of a combined effect of multiple inuences. Irrespec-
tive of the reasons for the decline, accurate description
of geographic variation is essential not only to our
understanding the biology of E. jubatus, but also to
provide a reasonable basis for management decisions.
Bickham et al. (1996) were the rst to provide evidence
of a discrete genetic discontinuity at 144°W (based on
mitochondrial DNA (mtDNA) control region sequences

2 oc c a S i o n a l pa p e r S , mu S e u m o f te x a S te c h un i v e r S i t y
Figure 1. Map of the distribution of E. jubatus. Region designations are as follows: OKH = Sea of Okhotsk,
KUR = Kuril Islands, KAM = Kamchatka Peninsula, COM = Commander Islands, WAL = Western Aleutian
Islands, CAL = Central Aleutian Islands, EAL = Eastern Aleutian Islands, WGA = Western Gulf of Alaska,
BER = Bering Sea, CGA = Central Gulf of Alaska, PWS = Prince William Sound, SEA = Southeastern Alaska,
BRC = British Columbia, ORE = Oregon, NCA = Northern California.
from pups sampled at their natal rookeries) in an oth-
erwise nearly continuous distribution. Those authors
recognized eastern and western stocks to either side of
this line. Subsequent studies conrmed this genetic
subdivision and recognized a third population, the
Asian stock, also using the maternally inherited mtDNA
genome (Fig. 2; Bickham et al. 1998; Baker et al. 2005;
Harlin-Cognato et al. 2005). Loughlin (1997) further
legitimized the separation of eastern and western stocks
through phylogeographic methods. A recent study also
validated the genetic subdivision between the eastern
and western stocks utilizing bi-parentally-inherited
nuclear microsatellite markers but the Asian stock was
not well resolved (Hoffman et al. 2006). Based upon a
branding study carried out over 24 years, there is little
indication of exchange between the eastern and western
stocks (Raum-Suryan and Pitcher 2002). In contrast,
Brunner (2002) investigated the geographic structur-
ing across the distribution of E. jubatus using cranial
morphometrics. She found patterns of geographical
partitioning of morphological differences, however
apparently not concordant with previously identied
genetic clines. Rather, she reported specimens from
California to be morphometrically distinct from Alas-
kan eastern and western stock samples. Unfortunately,
adequate specimens do not exist in collections to per-
form a meaningful study of geographic variation and
she only sampled two individuals from southeastern
Alaska. It is clear from the genetics data that Califor-
nian Steller sea lions are not distinct from other eastern
stock populations including southeastern Alaska.
Currently, the eastern and western stocks are be-
ing managed independently largely due to the observed
signicant differences in population trends separating
them. For example, the western stock numbers were
previously observed to decline at a rate of about 5%
per year (Sease and Gugmundson 2002), but now show
potential signs of stabilization and growth (Fritz and
Stinchcomb 2005). In contrast, eastern stock numbers
have been documented as being close to their highest
recorded size (Calkins et al. 1997). Recognizing the

ph i l l i p S e t a l .—Su b S p e c i e S o f St e l l e r Se a li o n S 3
Figure 2. Neighbour-joining trees constructed from Slatkin’s linearized Fst for a) the
mitochondrial control region (Baker et al. 2005; n = 1,568) and b) 13 microsatellite loci
(Hoffman et al. 2006; n = 668). Region designations are as described in Figure 1.

4 oc c a S i o n a l pa p e r S , mu S e u m o f te x a S te c h un i v e r S i t y
Skulls of 61 male and 66 female E. jubatus
were examined from various collections (Appendix).
Forty skull measurements (Fig. 3, Table 1) were taken
using Mitutoyo digital calipers. The measurements
are almost identical to those used by Brunner (2002).
Differences between our measurements and Brunner’s
(2002) pertain to a discrepency in the observed dental
formula of E. jubatus. Apparently, the measurement
description listing and skull illustration is that of the
California sea lion, Zalophus californicus, and this is
observed dissimilarities in population trends and the
genetic differentiation of these two populations (Bick-
ham et al. 1996; Loughlin 1997), the western stock is
now considered endangered while the eastern stock is
listed as threatened under the ESA (Loughlin 1998;
Calkins et al. 1999).
Because numerous genetic studies and contrasting
patterns of population growth have demonstrated the
validity of the population subdivision of E. jubatus, the
purpose of the current study was to further investigate if
the eastern and western stocks differ in skull morphol-
ogy, and if so, to reassess the taxonomy of the species to
reect this major feature of geographic variation. Gray
ma t e r i a l S a n d me t h o d S
(1859) described Arctocephalus monteriensis based on
a skull of a Steller sea lion and a skin of a fur seal and
this name could apply to any recognized taxon related
to the Steller sea lion. Typically the skull is considered
to be most diagnostic in mammalian systematics and it
should represent the type specimen for the taxon. While
there has traditionally been debate over the application
of subspecies designations, it should be apparent that
this rank contains substantial information regarding
geographic variation. Its use is particularly pertinent
when it describes the major patterns of geographic
variability found within a species and when there is
concordance of genetic and morphological patterns
(Avise and Ball 1990).
the basis of our decision to include a new listing and
illustration of measurements in this manuscript rather
than referencing the reader to Brunner (2002). Ad-
ditionally, data collected by Brunner (2002) was not
compiled with data gathered in this study because of
spurious patterns that would likely arise due to compar-
ing measurements taken by different individuals.
Data pertaining to sex and locality was also
recorded for each individual. Only individuals that
Figure 3. Sketch illustrating 40 measurements taken for each skull at dorsal, ventral, and lateral perspectives. See
Table 1 for descriptions of characters.

ph i l l i p S e t a l .—Su b S p e c i e S o f St e l l e r Se a li o n S 5
Variable # Variable description
1 Condylobasal length, from gnathion to posterior of basin
2Gnathion-middle of occipital crest
3Gnathion-posterior margin of nasals
4 Width of anterior nares, from interior of nares at widest point
5Greatest length of nasals, from anterior margin of nasal to posterior margin
6 Breadth of preorbital processes
7Interorbital constriction
8 Breadth at supraorbital processes, measured at widest point
9 Breadth of braincase, measured dorsally at coronal suture
10 Occipital crest-mastoid, from mid-occipital crest to ventral margin of mastoid
11 Palatal notch-incisors, from anterior point of palatal notch to posterior edge of central incisor alveoli; where a
palatal cleft was present, measurement was taken from palatal notch at margin of, but excluding, cleft
12 Distance behind border of canines, from posterior margin of canine alveolus to posterior margin of postcanine 5
alveolis
13 Rostral width, at widest margin of rostrum
14 Gnathion-posterior end of maxilla (palatal)
15 Breadth of zygomatic root of maxilla, maximal breadth anteroposterior from ventral perspective
16 Breadth of palate between postcanine 3, at medial edge of alveoli
17 Breadth of palate between postcanine 4, at medial edge of alveoli
18 Gnathion-caudal border of postglenoid process
19 Zygomatic breadth, at widest point of zygomatic arch, from posterior of squamosals
20 Basion-zygomatic root of maxilla, ventral perspective, from anterior of basion to anterior of zygomatic roots
21 Auditory breadth, greatest distance at auditory bullae
22 Mastoid breadth
23 Basion-bend of pterygoid, from anterior of basion to anterior of pterygoid
24 Height of canine above alveolus, a straight line from the anterior margin of alveolus to the tip of the canine
25 Gnathion-maxillary squamosal suture, from gnathion to ventral margin of suture
26 Height of skull at supraorbital process, from the base of skull at the middle of diastima to the top of the skull at
supraorbital
27 Height of skull at bottom of mastoid, dorsoventrally from skull at base at sagital crest to ventral margin of mas-
toid
28 Height of sagital crest, at greatest height
29 Mesiodistal diameter of alveolus of postcanine 2
30 Length of mandible, from posterior margin of condyle to anterior margin of dentary
31 Length of mandibular teeth row (inclusive of canines), from anterior margin of canine alveolus to posterior margin
of postcanine 6 alveolus
32 Mesiodistal diameter of canines, across base of canine at alveolus
33 Length of lower postconine row, from anterior margin of postcanine 1 alveolus to posterior margin of postcanine
6 alveolus
34 Height of mandible at meatus, from dorsal margin of angularis at meatus to dorsal margin of coronoid process
35 Angularis-coronoideus, from ventral margin of angularis to dorsal margin of coronoid process
36 Length of masseteric fossa, from anterior margin of fossa to posterior margin of coronoid process
37 Breadth of masseteric fossa, dorsoventrally through centre of fossa
38 Gnathion-hind border of preorbital process, from gnathion to posterior margin of preorbital process
39 Length of orbit-from ventral margin of supraorbital process to dorsal margin of the vase of orbit
40 Breadth of orbit-mesiodistal from inside margin of orbit
Table 1. Description of cranial measurements (modied from Brunner 2002).

6 oc c a S i o n a l pa p e r S , mu S e u m o f te x a S te c h un i v e r S i t y
could be identied unequivocally as adults, based
primarily on suture indexing following the methods
of Sivertsen (1954), and when possible from age data
obtained from tooth annulations, were measured to re-
move potential error associated with allometric growth
and size variation of non-adult E. jubatus. Data on the
exact geographic origin of skulls was not available;
therefore specimens were assigned to the eastern or
western stocks based on their collection locality rather
than by afliation with a specic rookery. For purposes
of analysis, 144°W was used to dene the geographic
division between eastern and western stocks.
All analyses were performed using SAS 9.1
software (SAS Institute Inc.). Due to the fragmented
nature of a portion of the skulls available for examina-
tion, 6.05% of the measurements were not taken for
some individuals. A multiple imputation procedure
was performed to predict the missing values (Rubin
1976; Schafer and Graham 2002). Measurements were
standardized prior to analysis. Two-tailed t-tests were
implemented to detect a statistically signicant differ-
ence between males and females and were the basis
for their separation in subsequent analyses. Two-tailed
t-tests were also used to identify sex-specic variables
signicantly associated with stock assignment. Because
the variance of the means of variables between stocks
were found to be unequal for males, the Satterthwaite
method (Satterthwaite 1946) of conducting t-tests was
employed for these samples. This method provides a
t statistic that asymptotically approaches a t distribu-
tion, thus allowing for a t-test to be calculated when
variances are unequal. Pearson correlation matrices
were generated to examine correlations of variables and
variables with stock. Alpha values for t-tests calculated
within each sex and for correlations were set at 0.1.
This value was selected over the traditionally used 0.05
to avoid the exclusion of biologically signicant nd-
ings due to overly strenuous statistical rigor. Because of
the binary nature of the class variable (stock), a logistic
regression with stepwise model selection was used to
determine the optimal combinations of variables that
predict correct stock assignment for each sex. Assess-
ing the predictive power of the selected variables was
done by randomly drawing two-thirds of the popula-
tion to build a logistic regression model that was then
applied to the remaining one-third of the population
for which the failure rate of stock assignment by the
model was retained. This process was iterated 1,000
times and the average failure rate was used as a means
of assessing the predictive power of the selected vari-
ables. Finally, canonical discriminant analysis (CDA)
was implemented as a multivariate variable reduction
method to produce linear combinations of quantitative
variables that summarize between-stock variation. The
resulting orthogonal variables were plotted against each
other to visualize patterns of stock differentiation.
re S u l t S
For males, ten variables yielded signicant values
in t-tests and showed signicant correlation (P = 0.1)
with stock (Table 2). Of these variables, three (15, 16,
22; Fig. 1, Table 1) were chosen through the stepwise
selection procedure of the logistic regression as the best
combination for correctly assigning males to eastern
or western stocks. Through 1,000 iterations of model
building and testing, these variables correctly assigned
male skulls to their stock of origin 88.13% and 86.59%
for the eastern and western stocks, respectively.
Analyses conducted for female sea lions showed
that six variables were signicant in t-tests and showed
signicant correlations with stock (Table 3). Of these
six variables, ve (4, 11, 14, 15, 29, 40; Fig. 1, Table 1)
were also selected in the stepwise selection procedure
of the logistic regression to be the optimal combination
of discriminating variables. Through 1,000 iterations
of model building and testing, these variables cor-
rectly assigned female skulls to their stock of origin
86.27% and 88.1% for the eastern and western stocks,
respectively.
For both sexes, plots of the rst two canonical
variables from the CDA produced two major clusters
of data points with minor overlap representative of the
eastern and western stocks (Fig. 4)

ph i l l i p S e t a l .—Su b S p e c i e S o f St e l l e r Se a li o n S 7
Table 2. Summary statistics for male E. jubatus grouped by stock including means, stan-
dard deviations, parameter estimates for the t-test, Pearson correlation coefcient, and
corresponding parameter estimate. Variables listed were signicant for t-tests and those
demarked with an asterisk (*) were selected through the stepwise procedure of the logistic
regression.
Table 3. Summary statistics for female E. jubatus grouped by stock including means,
standard deviations, parameter estimates for the t-test, Pearson correlation coefcients,
and corresponding parameter estimates. Variables listed were signicant for t-tests and
those demarked with an asterisk (*) were selected through the stepwise procedure of the
logistic regression.
Variable Eastern stock Western stock P Correlation
with stock
P
13 95.04 ± 6.27 88.81 ± 10.31 0.009 0.355 0.005
14 184.33 ± 8.45 179.5 ± 12.74 0.097 0.225 0.080
15* 50.925 ± 3.12 46.494 ± 4.65 0.000 0.501 0.000
16* 57.68 ± 4.75 52.46 ± 7.31 0.003 0.402 0.001
17 61.54 ± 5.13 56.40 ± 7.39 0.004 0.385 0.002
20 261.03 ± 12.26 252.05 ± 18.84 0.038 0.281 0.029
22* 205.30 ± 14.18 196.18 ± 24.88 0.090 0.229 0.076
26 101.06 ± 5.10 95.69 ± 9.28 0.010 0.351 0.006
28 24.939 ± 6.91 17.59 ± 8.84 0.001 0.429 0.000
40 74.84 ± 3.18 72.80 ± 4.52 0.053 0.230 0.043
Variable Eastern stock Western stock P Correlation
with stock
P
4* 32.44 ± 2.54 31.37 ± 2.01 0.07 0.23 0.07
11* 141.20 ± 6.38 144.54 ± 6.44 0.05 -0.24 0.05
14 145.57 ± 6.9 149.78 ± 8.08 0.04 -0.25 0.04
15* 37.77 ± 4.64 36.21 ± 2.28 0.03 0.27 0.03
29* 12.73 ± 0.97 13.39 ± 1.04 0.02 -0.30 0.02
40* 65.77 ± 2.87 64.42 ± 2.60 0.06 0.23 0.06

8 oc c a S i o n a l pa p e r S , mu S e u m o f te x a S te c h un i v e r S i t y
di S c u S S i o n
Figure 4. Plots of canonical vaiables 1 and 2 from the canonical discriminant analysis for a) males and b) females.
Results of the statistical analysis for both males
and females show a notable difference in skull morphol-
ogy of the eastern and western stocks of E. jubatus. Se-
lected combinations of variables for males and females
proved to correctly assign individuals to their respective
putative stocks more than 85% of the time.
The observation that all 10 statistically signicant
variables for males were on average larger for eastern
specimens suggests that a major distinguishing mor-
phological characteristic separating the eastern and
western stocks of male E. jubatus is overall size of
skull, with the eastern stock being larger. In addition,
it was observed that each of the statistically signicant
variables for males showed higher levels of within-
stock variation in the western stock relative to the
eastern stock (Table 2). These ndings indicate that
while male western stock E. jubatus on average have
smaller skulls than eastern stock individuals, there is
an elevated level of skull size variation in the western
stock relative to the eastern.
Summary statistics for the females indicate dif-
ferences between stocks to have a shape basis, rather
than one of size, as four signicant variables show
greater mean values in the western stock and two
signicant variables have greater mean values in the
eastern stock.
In the previous study of skull morphology of E.
jubatus, Brunner (2002) observed clustering patterns
for males that grouped Alaskan eastern stock and west-
ern stock specimens together separate from Californian
(eastern stock) specimens and was interpreted as being
discordant with previous genetic ndings; however this
conclusion was based on a sample size of two from
eastern Alaska. Clearly this is insufcient to refute the
highly corroborated genetics ndings (including both
maternally inherited mtDNA and biparentally inherited
nuclear microsatellites) which are also consistent with
the unique population trends of the two stocks. Brun-
ner’s (2002) study also included specimens from the
Asian stock and found them to be morphologically
distinct, showing the largest amount of differentiation
between the western stock and the Asian stock. In the
current study we do not address the relationship of the
Asian stock to the western and eastern stocks as the
degree of genetic differentiation between them is not as
strong as between the eastern and western stocks.
Subspecies are the least inclusive category rec-
ognized with formal taxonomic rank and consist of
geographically dened populations within a species
that differ taxonomically from other populations within
the same species (O’Brien and Mayr 1991). Avise and
Ball (1990) suggested subspecies be recognized using
multiple, independent, genetically based traits. We fol-
low the Turtle Taxonomy Working Group (2007) who
propose that “subspecies classication, if used, should
describe the major patterns of variation found within a
species.” O’Brien and Mayr (1991) also provide some
guidance when diagnosing subspecies by stating that
subspecies should share a “unique geographic range
or habitat, a group of phylogenetically concordant

ph i l l i p S e t a l .—Su b S p e c i e S o f St e l l e r Se a li o n S 9
characters, and a unique natural history relative to
other subdivisions of the species.” Multiple studies
(Bickham et al. 1996; Bickham et al. 1998; Baker et al.
2005; Hoffman et al. 2006) as well as the current study
have established the rst and second criteria, and the
third criterion is apparent due to the different population
trajectories of the eastern and western stocks.
From an evolutionary perspective, Harlin-
Cognato et al. (2006) discovered through nested-clade
analysis that the most ancient subdivision within E.
jubatus is that separating the eastern and western stocks
and that this separation was repeated through multiple
glacial cycles. Furthermore, those authors showed
that the break between the eastern and western stocks
is geographically concordant with phylogeographic
breaks of several other species of marine mammals.
While the evolutionary fate of any subspecies is
unknown (subdivision, extinction, intergradation, or
speciation), the utilization of subspecic taxonomic
designations provides information about geographic
variation in and of itself (Zusi 1982). Although some
taxonomists believe the subspecies category should be
discarded, we feel that because of the importance of
Steller sea lions as an indicator of the environmental
health of the North Pacic Ocean, the endangered
status of the western stock of Steller sea lions, and the
historical importance of subspecies in systematic mam-
malogy, it is appropriate to elevate these populations
to subspecies rank.
The western and Asian stocks will receive the
taxonomic designation of Eumetopias jubatus jubatus
because the type locality for the species is the Com-
mander Islands. The potential that the Asian stock is
a unique subspecies itself should be investigated by
additional research, but currently will be classied with
the western stock based on the their relationship inter-
preted through genetic data. The name Arctocephalus
monteriensis (Gray 1859) is available with the type
locality being Monterey, California, USA. Clearly, the
samples used in this study and by Brunner (2002) cor-
respond to the taxon described by Gray. The appropri-
ate trinomen for the eastern stock becomes Eumetopias
jubatus monteriensis. We propose the vernacular name
“Loughlin’s northern sea lion” to honor Dr. Thomas R.
Loughlin in recognition of his many years of research
on all aspects of the biology of Steller sea lions. We
interpret the distribution of E. j. monteriensis to corre-
spond to that of the eastern stock because of the strong
genetic signal and thus all rookeries east of 144oW are
included in this taxon.
The following synonymy modied from Loughlin
et al. (1987) details the taxonomic changes proposed
in this paper:
Eumetopias jubatus (Schreber 1776)
Steller sea lion or northern sea lion
Synonyms:
Leo marinus Steller 1751:360. No
type specimen; based on description from
Commander Islands; unavailable name (pre
Linnaean).
Phoca jubata Schreber 1776:300, pl.
83b. Type locality “northern part of the Pacic
Ocean,” Russian Commander Islands, Bering
Island. Description based on Steller’s notes
(Scheffer 1958).
Otaria stellerii Lesson 1828:420. A
renaming of Phoca jubata Schreber.
Arctocephalus monteriensis Gr ay
1859:358, 360, pl. 72. Type locality, Monterey,
California. (Based on a skull of Eumetopias
and skin of Callorhinus; we establish the Eu-
metopias skull to be the type specimen.)
Eumetopias jubatus jubatus (Schreber);
western Steller sea lion, distributed from
144oW west to Sea of Okhotsk. (NMML 316
skull is here designated to be the type speci-
men.)
Eumetopias jubatus monteriensis (Gray)
new combination; Loughlin’s northern sea
lion, distributed from central California to
southeastern Alaska.
While the long-term survival of the Steller sea
lion is uncertain, there is indication that the species has
maintained a relatively high level of genetic diversity
in spite of the recent decline in population numbers
(Bickham et al. 1998). In light of this, the management
of E. j. jubatus and E. j. monteriensis as distinct taxa
will help to promote the species’ continued existence
and the stability of the Northern Pacic ecosystem.

10 oc c a S i o n a l pa p e r S , mu S e u m o f te x a S te c h un i v e r S i t y
li t e r a t u r e ci t e d
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Baker, A. R., T. R. Loughlin, V. Burkanov, C. W. Matson,
R. G. Trujillo, D. G. Calkins, J. K. Wickliffe, and
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jubatus). Journal of Mammalogy 77:95-108.
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in Marine Mammals and the Exxon Valdez (T.
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ac k n o w l e d g m e n t S
We thank those who were so amiable in allowing
access to collections used in this study, especially Jim
Thomason, Raymond Bandar, Maureen Flannery, Jim
Patton, and Bruce Patterson. We also thank Russell
Long, the Director of Project Assessment for Purdue
University’s Engineering Education Department for
statistical advice. NOAA Fisheries’ Alaska Fisheries
Science Center provided funding for this research.
Dr. Al Gardner and Dr. Hugh Genoways generously
provided advice on issues of taxonomy and nomen-
clature. Finally, we are highly indebted to Dr. Thomas
Loughlin who led for many years the Steller sea lion
research program for NOAA. His dedication to the
research, conservation, and management of this spe-
cies is unmatched.
July 2003 and 2004. NOAA Technical Memoran-
dum NMFS-AFSC-153. 56 p.
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Spaniards, on the coast of California. Proceedings
of the Zoological Society of London 1859:357-
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Addresses of authors:
ca l e b d. ph i l l i p S
Center for the Environment and Department
of Forestry and Natural Resources
Purdue University
West Lafayette, IN 47907
phillip6@purdue.edu
Jo h n w. bi c k h a m
Center for the Environment and Department
of Forestry and Natural Resources
Purdue University
West Lafayette, IN 47907
bickham@purdue.edu
Jo h n c. pa t t o n
Center for the Environment and Department
of Forestry and Natural Resources
Purdue University
West Lafayette, IN 47907
jcpatton@purdue.edu
th o m a S S. ge l a t t
National Marine Mammal Laboratory
National Marine Fisheries Service, NOAA
7600 Sand Point Way, NE
Seattle, WA 98114
tom.gelatt@noaa.gov

12 oc c a S i o n a l pa p e r S , mu S e u m o f te x a S te c h un i v e r S i t y
ap p e n d i x
General information for specimens of E. jubatus used in the analysis. Acronym prexes included in
specimen accession numbers refer to the museum from which they were obtained. CAS = California
Acadamy of Sciences; MVZ = Museum of Vertebrate Zoology, University of California, Berkeley;
NMML = National Marine Mammal Laboratory, Washington; RB = Ray Bandar’s home collec-
tions.
Specimen accession no. Sex Date collected Collection locality
CAS1120 f 28 June 1915 San Mateo Co., CA
CAS13818 f 24 February 1966 San Mateo Co., CA
CAS13819 f 31 July 1966 Pacica Co., CA
CAS21393 f 17 August 1973 Pacica Co., CA
CAS21394 f 7 August 1973 Sonoma Co., CA
CAS21395 f 22 June 1975 Marin Co., CA
CAS21397 f 16 September 1972 Marin Co., CA
CAS21398 f 2 August 1973 Marin Co., CA
CAS21755 f 26 May 1977 Marin Co., CA
CAS23005 f 29 December 1987 Marmot Island, AK
CAS23013 f 3 August 1988 Mendocino Co., CA
CAS23167 f 27 September 1989 San Francisco Co., CA
CAS23964 f 8 July 1996 San Mateo Co., CA
MVZ118620 f 23 July 1956 Monterey Co., CA
MVZ172086 f 26 February 1982 Sonoma Co., CA
MVZ186326 f 16 September 1999 San Mateo Co., CA
MVZ191004 f 4 March 1902 Marin Co., CA
MVZ4114 f 29 September 1908 Monterey Co., CA
MVZ4770 f 1 April 1906 Seward, AK
MVZ4967 f 1 April 1906 Seward, AK
MVZ88876 f 15 August 1939 Clatsof Co., OR
NMML1296 f 2 February 1977 Port Fidalgo, AK
NMML1297 f 28 April 1977 Kodiak Island, AK
NMML1300 f 8 October 1982 Akutan Island, AK
NMML1313 f 21 March 1984 Shelikof Strait,AK
NMML1523 f 28 April 1977 Cape Ugak, AK
NMML1535 f 11 October 1976 Sea Otter Island, AK
NMML1536 f 12 October 1976 Marmot Island, AK
NMML1542 f 14 October 1976 Marmot Island, AK
NMML1545 f 11 February 1977 Goose Island, AK
NMML1546 f 12 February 1977 Port Fidalgo, AK
NMML1549 f 12 February 1977 Port Fidalgo, AK
NMML1550 f 16 February 1977 Pleiades Islands, AK
NMML1554 f 22 March 1977 Outer Island, AK

ph i l l i p S e t a l .—Su b S p e c i e S o f St e l l e r Se a li o n S 13
Specimen accession no. Sex Date collected Collection locality
NMML1561 f 23 May 1977 Latex Rocks, AK
NMML1562 f 26 May 1977 Marmot Island, AK
NMML1563 f 26 May 1977 Marmot Island, AK
NMML1565 f 13 November 1977 Glacier Island, AK
NMML1566 f 14 November 1977 Chernabura Island, AK
NMML1572 f 21 March 1977 Cape St. Elias, AK
NMML1573 f 25 March 1977 Cape St. Elias, AK
NMML1574 f 19 April 1978 Wide Bay, AK
NMML1576 f 27 June 1978 Wide Bay, AK
NMML1630 f 21 October 1985 Marmot Island, AK
NMML1631 f 25 October 1985 Izhut Bay, AK
NMML1633 f 27 October 1985 Sea Otter Island, AK
NMML322 f 14 July 1958 Chernabura Island, AK
NMML323 f 20 June 1958 Chernabura Island, AK
NMML324 f 20 June 1958 Chernabura Island, AK
NMML331 f 11 July 1958 Chernabura Island, AK
NMML332 f 9 July 1958 Chernabura Island, AK
NMML333 f 11 July 1958 Chernabura Island, AK
NMML339 f 1 June 1958 Chernabura Island, AK
NMML343 f 27 June 1958 Chernabura Island, AK
NMML344 f 18 July 1958 Chernabura Island, AK
NMML347 f 22 July 1958 Chernabura Island, AK
NMML353 f 1 July 1958 Chernabura Island, AK
NMML355 f 27 July 1958 Chernabura Island, AK
NMML356 f 24 July 1958 Chernabura Island, AK
NMML357 f 19 July 1958 Chernabura Island, AK
NMML362 f 20 June 1958 Chernabura Island, AK
NMML363 f 9 July 1958 Chernabura Island, AK
NMML367 f 3 March 1958 Pigeon Point, AK
NMML372 f 5 June 1960 Little Kondiaji Island, AK
NNML1538 f 12 October 1976 Ecola State Park, OR
CAS1118 m 26 June 1915 San Mateo Co., CA
CAS21399 m 6 September 1973 San Mateo Co., CA
CAS23213 m 3 August 1988 Marin Co., CA
CAS23735 m 17 July 1992 Marin Co., CA
CAS23862 m 16 September 1994 Mendocino Co., CA
CAS24451 m 3 July 1999 San Mateo Co., CA
CAS3683 m 4 April 1909 St Paul Island, AK
ap p e n d i x (c o n t .)

14 oc c a S i o n a l pa p e r S , mu S e u m o f te x a S te c h un i v e r S i t y
Specimen accession no. Sex Date collected Collection locality
CAS3684 m 4 April 1909 St. Paul Island, AK
CAS6 m 30 June 1919 San Mateo Co., CA
CAS7659 m 19 July 1933 San Mateo Co., CA
CAS8 m 4 April 1909 Santa Cruz Co., CA
MVZ101430 m 5 September 1948 San Mateo Co., CA
MVZ119669 m 25 April 1959 Marin Co., CA
MVZ138679 m 9 June 1972 Monterey, Co., CA
MVZ138680 m 25 July 1925 San Mateo Co., CA
MVZ186325 m 26 August 1996 San Mateo Co., CA
MVZ4112 m 2 July 1907 San Mateo Co., CA
MVZ4117 m 2 July 1907 Monterey Co., CA
MVZ8821 m 30 June 1907 Santa Cruz Co., CA
MVZ91069 m 19 June 1940 Alameda Co., CA
NMML1321 m 28 March 1984 Shelikof Strait,AK
NMML1553 m 22 March 1977 Outer Island, AK
NMML1559 m 23 May 1977 Sugarloaf Island, AK
NMML1614 m 14 March 1982 Marmot Island, AK
NMML1640 m 26 April 1989 Camando Island, AK
NMML1641 m 17 December 1991 Shi Shi Beach, AK
NMML1660 m 5 August 1993 Seaview Beach, AK
NMML316 m 22 June 1950 St Paul Island, AK
NMML325 m 7 July 1958 Cherndabura Island, AK
NMML326 m 1 July 1958 Cherndabura Island, AK
NMML327 m 1 June 1958 Cherndabura Island, AK
NMML329 m 27 June 1958 Cherndabura Island, AK
NMML335 m 19 July 1958 Cherndabura Island, AK
NMML336 m 8 July 1958 Cherndabura Island, AK
NMML338 m 28 June 1958 Cherndabura Island, AK
NMML33O m 13 June 1958 Clubbing Rocks, AK
NMML341 m 1 July 1958 Cherndabura Island, AK
NMML342 m 7 July 1958 Cherndabura Island, AK
NMML346 m 1 July 1958 Cherndabura Island, AK
NMML351 m 22 July 1958 Cherndabura Island, AK
NMML352 m 3 July 1958 Clubbing Rocks, AK
NMML354 m 5 July 1958 Cherndabura Island, AK
NMML359 m 24 July 1958 Clubbing Rocks, AK
NMML360 m 1 July 1958 Cherndabura Island, AK
NMML361 m 19 July 1958 Cherndabura Island, AK
ap p e n d i x (c o n t .)

ph i l l i p S e t a l .—Su b S p e c i e S o f St e l l e r Se a li o n S 15
Specimen accession no. Sex Date collected Collection locality
NNML1298 m 13 November 1977 Glacier Island, AK
NNML350 m 2 July 1958 Cherndabura Island, AK
RB1029 m 1 July 1967 Cape Blanco Lighthouse, OR
RB2386 m 1 June 1976 San Mateo Co., CA
RB26609 m 18 July 1964 Marin Co., CA
RB2721 m 1 June 1979 Humboldt Co.,CA
RB2853 m 1 July 1980 Del Norte Co., CA
RB2854 m 1 July 1980 Humboldt Co., CA
RB3337 m 1 July 1986 Marin Co., CA
RB3451 m 1 July 1988 San Mateo Co., CA
RB3630 m 1 June 1991 San Mateo Co., CA
RB3805 m 1 October 1983 Marin Co., CA.
RB5152 m 1 July 1903 Marin Co., CA
RB5651 m 1 July 1905 Sonoma Co., CA
RB5654 m 1 June 1905 Marin Co., CA
RB5739 m 1 July 1906 Sonoma Co., CA
ap p e n d i x (c o n t .)

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