Chadwick Ecological Consultants, Inc.
5575 South Sycamore Street, Suite 101, Littleton, Colorado 80120
(303) 794-5530, Fax: (303) 794-5041, e-mail:
DRAFT
MEMORANDUM
TO: Jerry Raisch and The Temperature Group
FROM: Steve Canton, Chadwick Ecological Consultants, Inc., with Assistance from John Young, ASA Analysis & Communications, Inc.
DATE: April 22, 2005
RE: Review of Temperature Standards in Colorado=s Water Quality Standard for Temperature Implementation Guidance Draft 3
This memorandum provides a review of the temperature standards proposed in the Colorado Department of Public Health and Environment (CDPHE) document Colorado=s Water Quality Standard for Temperature Implementation Guidance Draft 3 (Guidance Document) dated April 5, 2005, and the CDPHE Basic Standards Proponent=s Prehearing Statement. Chadwick Ecological Consultants, Inc. (CEC), with assistance of John Young, ASA Analysis & Communication, Inc., conducted this review on behalf of the Temperature Group.
This memorandum has four main parts. First, we discuss the decision by CDPHE to remove the coolwater qualifier, which was contained in their original notice, and the resulting changes to the warmwater maximum weekly average temperature (MWAT) and Daily Maximum (DM) values. Second, the proposed rate of change associated with thermal shock is discussed. Third, the use of information regarding heat shock proteins as a basis for determining their proposed rate of change is discussed. Fourth, issues related to appropriate use of spawning criteria are discussed.
Deletion of the Coolwater Qualifier
Jerry Raisch and The Temperature Group Chadwick Ecological Consultants, Inc.
Page 9 DRAFT April 22, 2005
In the Prehearing Statement, the CDPHE states that the proposal for a coolwater qualifier was removed because it did not take into account that some coolwater species commonly occur in warmwater segments in Colorado, and Awould not be protected by the proposed warmwater temperature standards@. The CDPHE gives the example of the white sucker as a coolwater species that occurs in the lower reaches of the South Platte, the Arkansas River, and the Colorado River. This example given by CDPHE apparently comes from comments received from the Colorado Division of Wildlife (CDOW), which singles out creek chub, central stoneroller, white sucker, longnose dace, and yellow perch as species from the coolwater database which are found in warmwater segments.
The response of the CDPHE to the fact that coolwater species are sometimes found in warmwater segments was to remove the coolwater use qualifier. This decision is inappropriate and fails to address the underlying biology of the species listed as examples. The classification of species into cold, cool, and warmwater species underlying the CDPHE original notice was based on published literature, which generally relies on data regarding physiological optimum temperatures to classify a particular species into one of these three categories. The coolwater species noted by CDPHE as occurring in warmwater segments; i.e., creek chub, white sucker, and longnose dace, also commonly occur in coldwater segments in Colorado. If CDPHE believes it is necessary to use these species to calculate warmwater standards, then by the same logic, they should also include these species in the calculation of coldwater standards. In our opinion, the inclusion of a coolwater qualifier is still the most ecologically sound option.
The example of the white sucker found in warmwater segments used by CDPHE only points out that the white sucker is adapted to live in a broad temperature range - not that higher warmwater criteria would be detrimental to the white sucker. The white sucker is widely distributed in North American and can be found from the Rocky Mountains to the Atlantic Ocean and from the Arctic Circle south to New Mexico and northern Georgia (Scott and Crossman 1973, Lee et al. 1980, Baxter and Stone 1995). Research involving temperature and white suckers has shown upper incipient lethal temperatures for white suckers ranging from 26 to 35C, although preferred temperatures ranged from 14 to 27C (Wismer and Christie 1983). Additionally, white suckers have been shown to be very tolerant to a wide variety of anthropogenic stress reflecting the adaptability of this species (Trautman 1981, Ohio EPA 1987, Schrader 1989, Crumby et al. 1990, Bramblett and Fausch 1991, Simon and Emery 1995, Frenzel and Swanson 1996, Lyons et al. 1996, Emery et al. 1999, Halliwell et al. 1999, Jennings et al. 1999, Mundahl and Simon 1999, Niemela et al. 1999, Smogor and Angermeier 1999).
Jerry Raisch and The Temperature Group Chadwick Ecological Consultants, Inc.
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The creek chub is also widely distributed in North American and is the most common stream cyprinid in eastern North America (Scott and Crossman 1973). The creek chub can be found from the Rocky Mountains (eastern Montana, Wyoming, Colorado, and New Mexico) to the Atlantic Ocean and is absent only from most of Florida and the Coastal Plain of the southeastern states (Scott and Crossman 1973, Lee et al. 1980, Baxter and Stone 1995). Research involving temperature and creek chub has shown upper incipient lethal temperatures ranging from 25 to 33C (Wismer and Christie 1983). Creek chubs have also been shown to be very tolerant to a wide variety of anthropogenic stress and are often pioneering species which move into disturbed stream reaches before other species can recolonize (Ohio EPA 1987, Crumby et al. 1990, Simon and Emery 1995, Frenzel and Swanson 1996, Lyons et al. 1996, Halliwell et al. 1999, Jennings et al. 1999, Mundahl and Simon 1999, Niemela et al. 1999, Smogor and Angermeier 1999, Thoma 1999).
The central stoneroller is a common minnow found throughout the central and eastern United States (Lee et al. 1980). The western edge of this species range includes eastern Wyoming, Colorado, and New Mexico, and extends as far north as northern Minnesota and as far south as south central Texas (Woodling, 1985, Baxter and Stone 1995). Research involving temperature and central stonerollers has shown upper optimum temperatures ranging from as low as 13C to as high as 29C (Cherry et al. 1977, Coutant 1977, Spotila et al. 1979, Houston 1982). Such a wide range of optimum temperatures indicates a species with a high temperature tolerance range.
The longnose dace is another widespread minnow in North America that occurs from the Pacific to the Atlantic coasts across the northern United States, with a southern extension into Texas (Scott and Crossman 1973, Lee et al. 1980, Baxter and Stone 1995). Populations of longnose dace in Colorado represent the southern extension of the species along the Rocky Mountains. Populations are not present in bordering states to the west or the east (Lee et al. 1980). Research involving temperature and longnose dace has shown upper optimum temperatures of 21.2C and a critical maximum of 31.4C (Brazo et al. 1978, Wismer and Christie 1983).
Jerry Raisch and The Temperature Group Chadwick Ecological Consultants, Inc.
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The last species noted by CDPHE is the yellow perch. Yellow perch is native to the northcentral and northeastern United States and much of Canada. Yellow perch have been introduced in Colorado and are an important game fish in some reservoirs in Colorado. However, this species is uncommonly found in Colorado rivers and streams and is not an important game fish in these systems. Temperature data on yellow perch is extensive and demonstrates a wide range of upper optimum temperatures (Spotila et al. 1979, Carlander 1997), again demonstrating the wide range of temperatures many coolwater species can not only tolerate, but often thrive in.
Thus, the CDPHE decision to remove the coolwater qualifier is based on one introduced species and four native species with extremely wide temperature tolerance ranges. This decision to move these species into the warmwater database results in an MWAT value of 24.4C and a DM value of 29.9C. These values are 3C to 4C lower than the warmwater standards originally noticed by the CDPHE would be without inclusion of coolwater species. This creates an unnecessarily restrictive standard for warmwater streams. Such a standard will only cause the need for many site specific criteria and unnecessarily increase the number of 303(D) water bodies.
A more prudent course of action for the CDPHE would be to consider a wider range of waters for coolwater designation. Previously, the CDPHE indicated that coolwater segments would be designated where coldwater and warmwater segments currently are adjoined. The CDPHE should not be so rigid, but rather examine waters on a case by case basis and allow for the coolwater designation wherever it can be shown that such a designation would be appropriate (e.g., spring-fed plains streams). This would afford protection to coolwater species while not creating unrealistic standards for all lower elevation water bodies in eastern and western Colorado. The current standards in the Guidance Document are applying a coolwater standard to all warmwater segments of the state, which is not only overly conservative, but will also be impossible for many waters to meet under ambient conditions.
Other Issues
The calculated MWAT and DM values for several species have changed in the Guidance Document from that used for derivation of values in the original notice. For example, the CDPHE presents an MWAT of 24C for the creek chub, when the CDPHE database did not previously have sufficient data to establish an MWAT for this species. If CDPHE has obtained additional data, especially on a contentious species (coolwater species added to the warmwater database), MWAT and DM values should be independently examined and verified.
Jerry Raisch and The Temperature Group Chadwick Ecological Consultants, Inc.
Page 9 DRAFT April 22, 2005
Thermal Shock - Rate of Change
The Guidance Document proposes a rate of change of no more than 4 C per hour (not to exceed 12C in 24 hours). The Prehearing Statement indicates that this number represents the lower end of the tempering range (i.e., acclimation rate) used by CDOW when hatchery fish are stocked into Colorado waters. The rational for using the more conservative rate was that Astocking of any given fish is a one-time event@ and Aan additional level of protection is appropriate where the fish community could experience these changes on a daily basis.@
Using this logic, the CDPHE is apparently suggesting that acclimated fish in natural environments are more susceptible to thermal shock than unacclimated, hatchery reared fish. This logic is flawed as fish raised in natural environments are already adapted and acclimated to changes in temperature associated with the natural thermal regime of the water body. However, hatchery fish are reared at nearly constant temperatures, which would make them more susceptible to thermal shock. Hatchery reared fish are then exposed to temperature changes varying from 4.2C to 13.2C per hour as part of the stocking process. Yet, despite this rapid change in temperature, hatchery-reared fish generally do not experience catastrophic die off soon after stocking, indicating that wild fish should handle such temperature changes readily. There is no reason why the CDPHE should assume that wild fish should be harmed by temperature changes in this range. The CDPHE should allow the rate of change for temperature of at least the intermediate value of 8.7C/hr from the CDOW protocol. As long as the temperature change does not increase temperatures to the point of the DM standard or result in the MWAT being exceeded, fish populations will be protected with this rate of change.
Thermal Shock - Heat Shock Proteins
The CDPHE justifies their initial proposal of 1C per hour and their revised proposal of 4C per hour based on Arates of 15C per hour, heat shock proteins have been shown to form in the tissues of rainbow trout@. The CDPHE gives no explanation on how it determined that the rate of change of temperature should be only 4C per hour or why a rate of change of 8.7C per hour would be inappropriate.
Jerry Raisch and The Temperature Group Chadwick Ecological Consultants, Inc.
Page 9 DRAFT April 22, 2005
Heat stress proteins (HSP) are a family of proteins that exist in the cells of all organisms. Some HSPs are formed during routine cell growth and development. Additional HSPs are synthesized when an organism is under environmental, chemical or physiological stress. The stress response has been mainly studied in mammalian cell lines or organisms normally maintained under constant laboratory conditions. There is much less information on the stress response of animals, such as fish, that have adapted to tolerate large fluctuations in environmental and internal conditions.
HSPs are thought to protect organisms from environmentally induced cellular damage. Both the magnitude and duration of the heat shock are important in determining the intensity of heat shock gene induction (Buckley and Hoffmann 2004). Expression of stress proteins in response to elevated temperatures has been associated with increased thermal tolerance in many cell lines, developing embryos, and adult organisms (DiIorio et al. 1996).
The role that HSPs play in influencing thermal tolerance of a whole animal is not clearly understood (Place and Hofmann 2001, Nakano and Iwama 2002). HSPs are believed to contribute to thermal adaptation in fishes through genetic interactions specific to particular environments (DiIorio et al. 1996). Some less thermally sensitive species may enhance thermal tolerance by having a large pool of cellular HSPs, allowing them to inhabit areas with relatively large and unpredictable fluctuations in environmental variables (Nakano and Iwama 2002).
Several families of heat shock proteins have been proposed as indicators of a generalized stress response at the cellular level. Recent findings that HSP levels, in various fish tissues, respond to a wide range of stressors have supported the use of these proteins as indicators of stressed states in fish. However, the cellular stress response is complex and varied. For example, different stressors evoke different HSP responses. Responses also vary by species and even organ tissue (Iwama et al. 2004). Care must be taken when interpreting the results of studies looking at a particular protein response in a particular tissue of a particular organism subject to a particular set of environmental factors, as changes in any of the variables would likely yield different results. Therefore, HSP use as indicators of stress in fish has been determined to be premature at present (Iwama et al. 2004) and not a dependable line of evidence to be used by the CDPHE to set rates if temperature change.
Jerry Raisch and The Temperature Group Chadwick Ecological Consultants, Inc.