Relationships between water temperatures and upstream migration, cold water refuge use, and spawning of adult bull trout from the Lostine River, Oregon, USA

Abstract

Understanding thermal habitat use by migratory fish has been limited by difficulties in matching fish locations with water temperatures. To describe spatial and temporal patterns of thermal habitat use by migratory adult bull trout, Salvelinus confluentus, that spawn in the Lostine River, Oregon, we employed a combination of archival temperature tags, radio tags, and thermographs. We also compared temperatures of the tagged fish to ambient water temperatures to determine if the fish were using thermal refuges. The timing and temperatures at which fish moved upstream from overwintering areas to spawning locations varied considerably among individuals. The annual maximum 7-day average daily maximum (7DADM) temperatures of tagged fish were 16-18°C and potentially as high as 21°C. Maximum 7DADM ambient water temperatures within the range of tagged fish during summer were 18-25°C. However, there was no evidence of the tagged fish using localized cold water refuges. Tagged fish appeared to spawn at 7DADM temperatures of 7-14°C. Maximum 7DADM temperatures of tagged fish and ambient temperatures at the onset of the spawning period in late August were 11-18°C. Water temperatures in most of the upper Lostine River used for spawning and rearing appear to be largely natural since there has been little development, whereas downstream reaches used by migratory bull trout are heavily diverted for irrigation. Although the population effects of these temperatures are unknown, summer temperatures and the higher temperatures observed for spawning fish appear to be at or above the upper range of suitability reported for the species.

An ecohydraulics virtual watershed: Integrating physical and biological variables to quantify aquatic habitat quality

“…Furthermore, it can also be influenced by behavioural cues and life history; developmental and migratory stage may have different thermal tolerances. Although ideal bull trout survival and reproduction temperature is less than 15 o C, Hillman and Essig () and Howell et al () have shown that they can adapt their life cycle to a wide range of temperature thresholds. The Environmental Protection Agency recommends a temperature range between 12 and 14 o C, which differs from the 4 to 10 o C optimal temperature for juvenile bull trout growth and rearing habitat.…”

“…Bull trout is a cold water obligate species and sensitive to temperature change (Fraley & Shepard, 1989;Rieman & Mclntyre, 1993); thermal requirements may vary with geographic area and life-history expression (Anglin et al, 2004;Hillman & Essig, 1998;Howell, Dunham, & Sankovich, 2010;Poole et al, 2001;Selong, McMahon, Zale, & Barrows, 2001). Furthermore, it can also be influenced by behavioural cues and life history; developmental and migratory stage may have different thermal tolerances.…”

“…Furthermore, it can also be influenced by behavioural cues and life history; developmental and migratory stage may have different thermal tolerances. Although ideal bull trout survival and reproduction temperature is less than 15 o C, Hillman and Essig (1998) and Howell et al (2010) Previous studies concluded that daily maximum temperature (DMT) above a critical threshold may be the major indicator for distribution of aquatic species (Olden & Naiman, 2010). Therefore, we used DMT as a metric for temperature suitability index (SI t ) for our study (Abatzoglou, Barbero, Wolf, & Holden, 2014).…”

Behavioural thermoregulation and bioenergetics of riverine smallmouth bass associated with ambient cold‐period thermal refuge

“…Depending on the system, thermal refuge may be available in the form of a tributary, varying water depth, outflow of a hydroelectric dam, discharge from a power plant cooling operation, hyporheic flow or groundwater discharge from a spring (Nielsen et al 1994;Peterson & Rabeni 1996;Torgersen et al 1999;Cooke et al 2004;Young & Isely 2007). Much of our current knowledge about thermal refuge use by fishes is based on salmonids (Torgersen et al 1999;Ebersole et al 2001;Howell et al 2010), but many other species of fish use thermal refuge (Peterson & Rabeni 1996;Labbe & Fausch 2000). Juvenile Coho salmon (Oncorhynchus kisutch) that thermoregulate in streams grew faster by moving between cold habitats with abundant food and warmer habitats that provided metabolic and assimilative benefits (Armstrong et al 2013).…”

Climate Change Simulations Predict Altered Biotic Response in a Thermally Heterogeneous Stream System

“…At a coarse spatial scale, groundwater can influence the distribution and abundance of aquatic organisms [23], [24] and reduce the occurrence of temperature fluctuations that may result in reproductive failure of certain species [25]. At fine spatial scales, some fishes show behavioral responses to thermal refuges by selecting spawning locations [26], [27], avoiding ice break up and frazil ice [28], or thermoregulating by occupying groundwater influenced areas during warm or cool water periods [16], [19], [20], [29].…”