Speciation of the Wandering Shrew Part 3

=Sorex vagrans sonomae= Jackson

_Sorex pacificus sonomae_ Jackson, Jour. Mamm., 2:162, August 19, 1921.

_Type._--Adult female, skin and skull; No. 19658, Mus. Vert.

Zool.; obtained on July 2, 1913, by Alfred C. Shelton, from Gualala, on the Sonoma County side of the Gualala River, Sonoma Co., California.

_Range._--Coastal California from Point Reyes north to Point Arena.

_Diagnosis._--Size large; average and extreme measurements of 3 topotypes are: total length, 141.7 (141-143); tail, 59 (54-63); hind foot, 17 (17-17). Color reddish in summer, somewhat grayer in winter.

[Ill.u.s.tration: FIG. 16. Probable geographic ranges of 16 subspecies of _Sorex vagrans_.

Guide to subspecies

1. _S. v. shumaginensis_ 2. _S. v. obscurus_ 3. _S. v. alascensis_ 4. _S. v. soperi_ 5. _S. v. isolatus_ 6. _S. v. setosus_ 7. _S. v. bairdi_ 8. _S. v. permiliensis_ 9. _S. v. yaquinae_ 10. _S. v. pacificus_ 11. _S. v. sonomae_ 12. _S. v. longiquus_ 13. _S. v. parvidens_ 14. _S. v. monticola_ 15. _S. v. neomexica.n.u.s_ 16. _S. v. orizabae_ ]

_Comparisons._--Differs from _S. v. pacificus_, with which it intergrades to the north, in average smaller size and somewhat darker color; differs from the sympatric _S. v. vagrans_ in much larger size and more reddish color in both summer and winter.

_Remarks._--This subspecies inhabits the Transition Life-zone below 300 feet, and occurs on moist ground in forests and beneath dense vegetation.

_Marginal records._--CALIFORNIA: Point Arena (Grinnell, 1933:82); Monte Rio (Jackson, 1928:144); Inverness (Grinnell, 1933:82).

=Sorex vagrans pacificus= Coues

_Sorex pacificus_ Coues, Bull. U. S. Geol. and Geog. Surv.

Terr., 3 (3):650, May 15, 1877.

_Sorex pacificus pacificus_, Jackson, Jour. Mamm., 2:162, August 19, 1921.

_Type._--Adult, s.e.x unknown, skin and skull; No. 3266 U. S. Nat. Mus.; date of capture unknown; received from E. P. Vollum and catalogued on March 8, 1858; obtained at Ft. Umpqua, mouth of Umpqua River, Douglas Co., Oregon.

_Range._--Coast of California and Oregon from Mendocino north to Gardiner.

_Diagnosis._--Size large, largest of the species; average and extreme measurements of 8 specimens from Orick, Humboldt Co., California, are: total length, 143.1 (134-154); tail, 65.5 (59-72); hind foot, 17.5 (16-19). Color reddish in summer, browner or grayer in winter.

_Comparisons._--See account of _S. v. sonomae_ for comparison with that subspecies; averaging larger in all dimensions than _S. v.

yaquinae_ with which it intergrades to the north; much larger and has more reddish than the sympatric _S. v. vagrans_.

_Remarks._--This subspecies occurs in the Canadian and Transition life-zones below 1500 ft. where there is found moist ground in or adjacent to heavy forests.

_Specimens examined._--Total number, 76.

OREGON: _Douglas Co._: Umpqua, 1 BS. _Coos Co._: Marshfield, 1 BS; Myrtle Point, 1 BS. _Josephine Co._: Bolan Lake, 1 SGJ.

CALIFORNIA: _Del Norte Co._: Smith River, 2 BS; Gasquet, 4 BS; Crescent City, 17 BS. _Humboldt Co._: Orick, 13 BS; 1 mi. N Trinidad, 18 FC; Trinidad Head, 1 BS; Carson's Camp, Mad River, Humboldt Bay, 5 BS; Arcata, 3 BS; Cape Mendocino, 2 BS; 5 mi. S Dyerville, 1 BS.

_Mendocino Co._: Mendocino, 6 BS.

_Marginal Records._--OREGON: Marshfield; Umpqua. CALIFORNIA: Gasquet; 5 mi. S Dyerville; Mendocino, thence up coast to point of beginning.

=Sorex vagrans yaquinae= Jackson

_Sorex yaquinae_ Jackson, Proc. Biol. Soc. Was.h.i.+ngton, 31:127, November 29, 1918.

_Sorex pacificus yaquinae_, V. Bailey, N. Amer. Fauna, 55:364, August 29, 1936.

_Type._--Adult female, skin and skull; No. 73051 U. S. Biol. Surv.

Coll., obtained on July 18, 1895, by B. J. Bretherton, from Yaquina Bay, Lincoln Co., Oregon.

_Diagnosis._--Size large for the species; average and extreme external measurements of 11 specimens from Oakridge, Lane Co., Oregon, are: total length, 125.3 (11-136); tail, 55.1 (49-61); hind foot, 14.9 (14-16). Color reddish in summer, browner or grayer in winter.

_Comparisons._--See account of _S. v. pacificus_ for comparison with that subspecies. Larger and more reddish than _S. v. bairdi_ with which it intergrades to the north and east. Much larger and more reddish than the sympatric _S. v. vagrans_.

_Remarks._--The name _yaquinae_ actually applies to a population of intergrades between _pacificus_ and _bairdi_. There is much variation over the range of the subspecies, and individuals from the western and southern parts are larger than those from the west slope of the Cascades. Specimens from Vida and McKenzie Bridge are smaller than those from Mapleton, Mercer, and the type locality but still seem closer to _yaquinae_ than to topotypes of _bairdi_. Between Marshfield and Umpqua on the one hand, and the Columbia River and the Cascade Mountains on the other, the size of _Sorex vagrans_ decreases quite rapidly from the large_ pacificus_ to the smaller _permiliensis_. Size decreases less rapidly northward along the coast than it does eastward toward the mountains; consequently, at any given lat.i.tude, coastal shrews are larger than mountain shrews. In this area of rapid change in size it is difficult to draw subspecific boundaries between _pacificus_, _yaquinae_, and _bairdi_, and this must be done somewhat arbitrarily.

Jackson (1928:141) remarked upon the possibility that intergradation between _pacificus_ and _yaquinae_ took place. He noted also the close resemblance between _yaquinae_ and _bairdi_, and stated (_loc. cit._) that specific affinity between the two might be demonstrated with more specimens. He had a series of eight specimens from Vida, Oregon, seven of which he a.s.signed to _S. o. bairdi_ and one to _yaquinae_. I have examined these specimens and find no more variation between the largest and the smallest than would be expected in any normally variable series of shrews. Vernon Bailey (1936:364) arranged _yaquinae_ as a subspecies of _pacificus_ without giving his reasons for so doing.

_Specimens examined._--Total number, 65. OREGON: _Lincoln Co._: type locality, 2 AW. _Benton Co._: Philomath, 2 BS. _Lane Co._: Mable, 1 OU; Vida, 4 BS, 1 OSC, 3 OU; McKenzie Bridge, 8 OSC, 3 AW, 17 OU, 2 SGJ; Mercer, 1 OSC, 1 OU; Mapleton, 3 BS; Oakridge, 11 OU. _Douglas Co._: Gardiner, 2 BS; Elkhead, 1 BS. _Klamath Co._: Crescent Lake, 3 OU.

_Marginal Records._--OREGON: Yaquina Bay; _Philomath_; McKenzie Bridge; Prospect (Jackson, 1928:140); Crescent Lake; Gardiner.

=Sorex vagrans bairdi= Merriam

_Sorex bairdi_ Merriam, N. Amer. Fauna, 10:77, December 31, 1895.

_Sorex obscurus bairdi_, Jackson, Proc. Biol. Soc. Was.h.i.+ngton, 31:127, November 29, 1918.

_Type._--Adult female, skin and skull; No. 17414/24318, U. S. Biol.

Surv. Coll.; obtained on August 2, 1889, by T. S. Palmer, from Astoria, Clatsop Co., Oregon.

_Range._--Northwestern Oregon, south to Otis and east to Portland.

_Diagnosis._--Size medium for the species; average and extreme external measurements of 6 specimens from the type locality are: total length, 126.3 (124-130); tail, 55.0 (52-57); hind foot, 15.0 (14-15).

Color Fuscous to Sepia in summer, darker in winter, underparts buffy.

_Comparisons._--For comparisons with _yaquinae_ see account of that subspecies. More reddish and larger than _permiliensis_ with which _bairdi_ intergrades to the east; specimens from Portland show evidence of such intergradation. Some specimens from southern Tillamook County show an approach to _yaquinae_.

_Remarks._--_S. v. bairdi_ lives primarily in forests as do _yaquinae_ and _pacificus_.

_Specimens examined._--Total number, 39. OREGON: _Clatsop Co._: type locality, 12 BS; Seaside, 3 BS. _Tillamook Co._: Netarts, 1 OU; Tillamook, 2 OSC; Blaine, 1 AW; Hebo Lake, 1 SGJ; 5 mi. SW Cloverdale, 1 AW. _Multnomah Co._: Portland, 6 USNM. _Lincoln Co._: Otis, 7 USNM; Delake, 1 KU. _Lane Co._: north slope Three Sisters, 6000 ft., 4 BS.

_Marginal Records._--OREGON: type locality; Portland; north slope Three Sisters; Taft (Macnab and Dirks, 1941:178).

=Sorex vagrans permiliensis= Jackson