Species Fact Sheet Hutton tui chub Gila bicolor ssp.
STATUS: THREATENED CRITICAL HABITAT: NONE
Hutton tui chub potentially occurs in these Oregon counties: Lake (Map may reflect historical as well as recent sightings)
The Hutton tui chub was listed as threatened in 1985. A recovery plan
was published in 1998. There is no critical habitat designation.
The Hutton tui chub is an undescribed subspecies of Gila bicolor,
a widespread minnow found in the arid western United States. The
Hutton tui chub is robust, with the greatest depth of body immediately
behind the head. This subspecies is distinguished from other tui
chubs in adjacent basins by morphology of the head. The head has
a convex outline, is longer, deeper, and the distance between
the eyes is greater than other tui subspecies.
Historic Status and Current
The Hutton tui chub is the only fish found in the Alkali Subbasin
in southwestern Oregon. Prehistorically, Alkali Lake likely reached
a maximum depth of 82.5 meters (270.7 feet) and covered about 2,331
square kilometers (1,448.4 square miles). Since that time the water
level has fluctuated, but with a drying trend. In 1977, the distribution
of the Hutton tui chub included only two springs in the Alkali subbasin,
Hutton Spring and an unnamed spring. Attempts to find this unnamed
spring in 1996 were unsuccessful and this population may have been
The Hutton tui chub occurs in Hutton Spring, Lake County, Oregon.
The size of the springhole of Hutton Spring varies with excavations
made by the owner. It has ranged from 6 meters (20 feet) to nearly
12 meters (40 feet) in diameter, and is about 4.5 meters (15 feet)
deep in the center. Hutton Spring is occupied in part by tules (Scirpus
Other vegetation present includes sedge (Carex sp.), saltgrass
and squirreltail (Sitanion hystrix). The fish use the vegetation
and whatever debris is present for cover. Some of the larger individuals
use the deep spring hole as cover. The recorded water temperature
is 64º F. (17.7º C), during the summer (May to October). The
outflow from the spring forms a small area of wetland adjacent
to the sources. This is occupied by grasses, water parsley, and
sedges. The spring is in a grassy area bordered to the north and
west by shrubby rangeland and to the east and south by the lake
bed of pluvial (rain-influenced) Alkali Lake. A low dry ridge with
sagebrush is immediately south of the spring area. Elevation at
the site is 1,371.6 meters (4,500 feet).
Reasons for Decline
The isolation of the Hutton tui chub is due to the
desiccation of pluvial Alkali Lake. Present status is in part
a result of past access by cattle to Hutton Spring. Threats to
tui chubs include: pumping of water from the springs, which occurred
in the past but is not occurring now; contamination of groundwater
by dispersal of chemicals from a herbicide manufacturing residue
disposal site 2.8 kilometers (1.75 miles) south of Hutton Spring;
and, modification of the springs (via heavy equipment - which in
turn causes other problems such as siltation, erosion, vegetation
cover loss, water diversion and drawdown).
Hutton Spring is privately owned and the habitat is in good condition
primarily due to conscientious long-term land stewardship by the
landowner. This habitat is currently fenced to exclude cattle
and is in stable condition. The Oregon Department of Environmental
Quality (DEQ) is currently monitoring groundwater contamination
from the chemical disposal site to the south of Hutton Spring.
The DEQ has determined that the contaminated plume is spreading
from east to west away from Hutton Spring and thus does not currently
constitute a threat to the water quality in Hutton Spring.
Bills, F.T. 1978. Taxonomic status of the isolated populations
of tui chub referred to as Gila bicolor oregonensis (Snyder).
MS Thesis, OR State Univ.
Bond, C.E. 1974. Endangered plants and animals of Oregon: I,
Fishes., OR Agricultural Experiment Station Special Report 205:
Snyder, J.O. 1908. Relationships of the fish fauna of the lakes
of southeastern Oregon. Bulletin of the U.S. Bureau of Fish XXVII
U.S. Fish and Wildlife Service. 1985. Determination of threatened
status for Hutton tui chub and Foskett speckled dace. FR
U.S. Fish and Wildlife Service. 1985. Special
take of Hutton tui chub and Foskett speckled dace. Federal Register