Relative Condition Parameters for Fishes of Montana, USA
by
, , and
Robert W. Eckelbecker
1,*,
Nathaniel M. Heili
2,
Christopher S. Guy
3 and
David A. Schmetterling
4 1
Montana Cooperative Fishery Research Unit, Department of Ecology, Montana State University, P.O. Box 173460, Bozeman, MT 59717, USA
2
Department of Ecology, Montana State University, Bozeman, MT 59717, USA
3
U.S. Geological Survey, Montana Cooperative Fishery Research Unit, Department of Ecology, Montana State University, P.O. Box 173460, Bozeman, MT 59717, USA
4
Montana Fish, Wildlife & Parks, 3201 Spurgin Road, Missoula, MT 59804, USA
*
Author to whom correspondence should be addressed.
Fishes 2023, 8(1), 28; https://doi.org/10.3390/fishes8010028
Submission received: 16 November 2022
/
Revised: 22 December 2022
/
Accepted: 28 December 2022
/
Published: 31 December 2022
Abstract
:Body condition indices are commonly used in the management of fish populations and are a surrogate to physiological attributes such as tissue-energy reserves. Relative condition factor (Kn) describes the condition of species relative to populations in a geographic area. We developed models to allow for the calculation of Kn in Montana, USA by using the weight–length data collected by Montana Fish, Wildlife & Parks. We generated log10weight–log10length relationships to obtain Montana specific parameter estimates for relative condition equations (W′) for 51 species and three subspecies. We developed separate models by water type (e.g., lotic and lentic) and sex for five species due to varying growth based on sexual dimorphism and varying ecosystem types. Relative condition offers the advantage of describing body condition relative to species in Montana, provides a condition index for species that do not have standard-weight models developed for relative weight (Wr), and affords more information for the global database on weight–length relationships of fishes.
1. Introduction
Weight and length measurements are commonly recorded in fisheries surveys and provide the foundation for research and management [1,2]. Fisheries biologists use weight–length relationships to estimate weight based on length, and vice versa, or to assess the variation from the expected weight for length as an index of relative plumpness of a fish [3]. Because weight is directly related to fish length, ratios between weight and length have been termed condition and are often used as a surrogate to physiological attributes (e.g., tissue-energy reserves) [2,4,5].
Fulton’s condition factor (K), relative condition factor (Kn), and relative weight (Wr) are the three most commonly used metrics to assess body condition in fishes [2]. Relative condition factor (Kn = W/W′), where W is the individual weight of a fish and W′ is the length-specific mean weight of a fish in the population under study and describes the condition of a species relative to populations in a geographic area [6]. This is achieved by comparing the weight of a fish to a standard predicted by a weight–length regression from the geographic area representing where the fish was sampled [3,6]. Geographic areas used to represent average weight–length relationships (W′) can be individual small waterbodies [7,8] or large watersheds and seas [9,10]. Swingle and Shell [6] used the state of Alabama as their geographic area for the development of W′ for 25 species. Here, we aim to replicate Swingle and Shell’s concept of a statewide condition index for Montana specific parameter estimates for relative condition.
2. Materials and Methods
We used fish weight and length data obtained from Montana Fish, Wildlife & Parks spanning the years 1951–2020 for fish sampled within the state of Montana. Each species data were downloaded individually using a query of species identification code, and weight and length greater than zero. Outliers were identified and excluded from future analysis as having an absolute value greater than three from a standardized residual cutoff on the loge weight–loge length linear relationship, which was repeated twice [11]. Due to the high variance in weights on small fish, all individuals below an identified minimum length were excluded from analysis [2]. We used the minimum length specified for species that currently have standard weight equations developed [2,12,13,14,15] and for species without a standard weight equation, a variance to mean ratio was used to find the centimeter length group that had a value less than 0.02 [16,17]. Weight can be predicted from the curvilinear model:
where W is weight, a is a constant, L is length, and b is an exponent that is generally different among species. The curvilinear model can be transformed to the following equation [18]:
where W is weight, L is length, a′ is the log10(a) and the y-intercept, and b is the slope. Using R package MCMC pack [19], an uninformed Bayesian linear regression was used to obtain parameter estimates of a′ and b for 51 fish species and three subspecies in Montana [20]. By using a Bayesian framework, we can infer the probability of varying estimates of a′ and b.
W = aLb,
log10(W) = a′+ b × log10(L),
Average Kn was calculated for the years 1980 and 2020 from the Yellowstone River and Missouri River for rainbow trout Oncorhynchus mykiss and brown trout Salmo trutta.
3. Results
Weight–length data from 51 species and three subspecies and 2,948,583 individuals were used to create parameter estimates for a′ and b and 95% credible intervals (Figures S1–S7). Lengths varied from 50 to 1,473 mm and weights varied from 2 to 56,246 g (Table 1). Intercept values (a′) varied from −6.962 to −4.157 and slopes (b) varied from 2.603 to 3.716 (Table 2).
Temporal and spatial variability in Kn for rainbow trout and brown trout was observed in two Montana rivers – these rivers were used as an example for illustrating the utility in assessing body condition. A decline in the average Kn was observed for both rainbow trout and brown trout in the Yellowstone River. Rainbow trout decreased from 1.11 in 1980 to 0.96 in 2020 while brown trout decreased from 1.12 in 1980 to 0.95 in 2020. Additionally, Kn for rainbow trout increased in the Missouri River from 0.97 in 1980 to 1.08 in 2020 while brown trout had a slight decline from 1.08 in 1980 to 1.02 in 2020.
4. Discussion
The analysis described here was conducted using data readily available from the statewide standardized web accessible database maintained by Montana Fish, Wildlife & Parks and contributes to the estimate of weight–length relationships for 26 species designated as game fishes in Montana statutes, 34 native fish species, and 19 invasive fish species for the state of Montana [21]. Due to varying growth based on sexual dimorphism and ecosystem type, separate models were developed by water type (e.g., lotic and lentic) for two species and two subspecies (e.g., brown trout Salmo trutta, rainbow trout Oncorhynchus mykiss, westslope cutthroat trout Oncorhynchus clarkii lewisi, and Yellowstone cutthroat trout Oncorhynchus clarkii bouvieri) and by sex for paddlefish Polyodon spathula [22,23,24,25,26]. The relative condition parameter estimates provide insight into growth patterns displayed in fishes and offers the ability to calculate a standardized condition factor for the 15 species that currently do not have standard-weight models developed (e.g., pygmy whitefish Prosopium coulterii).
Using the slope parameter, b, to describe the growth pattern of a fish, allometric growth (b ≠ 3) represents a fish that has less girth as length increases (b < 3) or has an increase in plumpness as length increases (b > 3) [2] and occurs more commonly among fish species compared to isometric growth [27]. Isometric growth (b = 3) describes a fish that grows with an unchanging body form [28]. We identify six species (e.g., green sunfish Lepomis cyanellus, lake chub Couesius plumbeus, longnose dace Rhinichthys cataractae, shorthead redhorse Moxostoma macrolepidotum, Columbia slimy sculpin Uranidea sp. cf. cognata, and stonecat Noturus flavus) as having isometric growth based on the 95% credible intervals of b including 3.0.
Relative condition (Kn) requires parameters of a′ and b to calculate W′ (log10W) and offers fisheries biologists a quantitative approach to assess trends in fish condition as a potential indicator of environmental changes and general state of well-being at a regional level [1,2]. We used the years 1980 and 2020 for the Yellowstone River and Missouri River to demonstrate how comparisons of Kn can be used to assess condition both temporarily and spatially. Relative condition factor comparisons can be further informed with the addition of covariates such as discharge, which can affect fish condition factor by reducing refuge, altering prey abundance, and reducing water quality [29,30]. Furthermore, condition factors can be used as a tool to assess prey abundance or fish density, and the ability to detect changes in condition can help biologists make management recommendations concerning fish populations [1,2].
Thirty-nine species and sub-species will now have a standard weight (Ws) and W′ relationship developed allowing for a regional, Montana, and range-wide index of comparison. One limitation of Kn is that a value of 1.0 is related to the average fish which may not describe a fish in good condition [2]. However, the relationship for W′ was created from fish represented in a regional geographic area. Relative weight (Wr) which uses Ws to assess fish condition on a range wide scale can still be biased based on the geographic distribution and quantity of samples that define the Ws equation [31]. By using relative condition and relative weight, biologist can employ more tools to evaluate and monitor body condition of fishes.
Supplementary Materials
The following are available online at https://www.mdpi.com/article/10.3390/fishes8010028/s1. Figure S1: Scatter plot of log10weight–log10length for arctic grayling, bigmouth buffalo, black bullhead, black crappie, blue sucker, bluegill, brook trout, and brown trout where we propose W′ parameters. Red line represents average fish in Montana as predicted from a Bayesian linear regression. Figure S2: Scatter plot of log10weight–log10length for bull trout, burbot, cisco, Columbia slimy sculpin, common carp, flathead chub, freshwater drum, golden shiner, and golden trout where we propose W′ parameters. Red line represents average fish in Montana as predicted from a Bayesian linear regression. Figure S3: Scatter plot of log10weight–log10length for goldeye, green sunfish, kokanee, lake chub, lake trout, lake whitefish, largemouth bass, largescale sucker, and longnose dace where we propose W′ parameters. Red line represents average fish in Montana as predicted from a Bayesian linear regression. Figure S4: Scatter plot of log10weight–log10length for longnose sucker, mountain sucker, mountain whitefish, northern pike, northern pikeminnow, paddlefish, and pallid sturgeon where we propose W′ parameters. Red line represents average fish in Montana as predicted from a Bayesian linear regression. Figure S5: Scatter plot of log10weight–log10length for peamouth, pumpkinseed, pygmy whitefish, rainbow trout, redside shiner, river carpsucker, rocky mountain sculpin, and sauger where we propose W′ parameters. Red line represents average fish in Montana as predicted from a Bayesian linear regression. Figure S6: Scatter plot of log10weight–log10length for shorthead redhorse, smallmouth bass, smallmouth buffalo, stonecat, tiger muskellunge, Utah chub, walleye, and westslope cutthroat trout where we propose W′ parameters. Red line represents average fish in Montana as predicted from a Bayesian linear regression. Figure S7: Scatter plot of log10weight–log10length for white sturgeon, white sucker, yellow bullhead, yellow perch, and Yellowstone cutthroat trout where we propose W’ parameters. Red line represents average fish in Montana as predicted from a Bayesian linear regression.
Author Contributions
Conceptualization, R.W.E., N.M.H., C.S.G., and D.A.S.; methodology, R.W.E., N.M.H., and C.S.G.; validation, R.W.E., and C.S.G.; formal analysis, R.W.E., N.M.H., C.S.G., and D.A.S.; investigation, R.W.E., N.M.H., C.S.G., D.A.S.; resources, D.A.S.; data curation, R.W.E., N.M.H.; writing—original draft preparation, R.W.E., N.M.H.; writing—review and editing, R.W.E., N.M.H., C.S.G., D.A.S.; visualization, R.W.E.; supervision, C.S.G., D.A.S.; project administration, C.S.G., D.A.S. All authors have read and agreed to the published version of the manuscript.
Funding
This research received no external funding.
Institutional Review Board Statement
Not applicable. Data for this study were from Montana Fish, Wildlife & Parks standardized database. Thus, animal use protocols were based on Montana Fish, Wildlife & Parks guidelines.
Data Availability Statement
Data available upon reasonable request from Montana Fish, Wildlife & Parks.
Acknowledgments
We would like to acknowledge Montana Fish, Wildlife & Parks for allowing access to their fisheries data along with the additional agencies and organizations that have contributed to the scientific records hosted by Montana Fish, Wildlife & Parks. The Montana Cooperative Fishery Research Unit is jointly sponsored by Montana State University; Montana Fish, Wildlife & Parks; and the U.S. Geological Survey. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Conflicts of Interest
The authors declare no conflict of interest.
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Table 1.
Minimum and maximum length and weight used to create weight–length relationship for 51 Montana fish species and three subspecies. All lengths are reported as total length except paddlefish, noted by †, that is measured from eye to fork of caudal fin. Cottidae species are noted with a ‡ as they are being described as new species. Columbia slimy sculpin were previously referred to as slimy sculpin Cottus cognatus and Rocky Mountain sculpin were previously referred to as mottled sculpin C. bairdii.
Table 1.
Minimum and maximum length and weight used to create weight–length relationship for 51 Montana fish species and three subspecies. All lengths are reported as total length except paddlefish, noted by †, that is measured from eye to fork of caudal fin. Cottidae species are noted with a ‡ as they are being described as new species. Columbia slimy sculpin were previously referred to as slimy sculpin Cottus cognatus and Rocky Mountain sculpin were previously referred to as mottled sculpin C. bairdii.
| Length (mm) | Weight (g) | Kn | |||||
|---|---|---|---|---|---|---|---|
| Species | Scientific Name | Min | Max | Min | Max | Min | Max |
| Acipenseridae | |||||||
| Pallid sturgeon | Scaphirhynchus albus | 325 | 1472 | 94 | 15,876 | 0.64 | 1.40 |
| White sturgeon | Acipenser transmontanus | 701 | 1460 | 1160 | 17,222 | 0.76 | 1.39 |
| Catostomidae | |||||||
| Bigmouth buffalo | Ictiobus cyprinellus | 163 | 905 | 73 | 13,450 | 0.76 | 1.29 |
| Blue sucker | Cycleptus elongatus | 437 | 884 | 680 | 7100 | 0.68 | 1.45 |
| Largescale sucker | Catostomus macrocheilus | 110 | 647 | 10 | 2774 | 0.66 | 1.55 |
| Longnose sucker | Catostomus catostomus | 90 | 597 | 6 | 2767 | 0.66 | 1.53 |
| Mountain sucker | Catostomus platyrhynchus | 100 | 246 | 9 | 181 | 0.45 | 2.30 |
| River carpsucker | Carpiodes carpio | 130 | 762 | 27 | 7711 | 0.70 | 1.43 |
| Shorthead redhorse | Moxostoma macrolepidotum | 100 | 581 | 9 | 2675 | 0.69 | 1.47 |
| Smallmouth buffalo | Ictiobus bubalus | 201 | 870 | 150 | 11,067 | 0.68 | 1.45 |
| White sucker | Catostomus commersonii | 100 | 564 | 8 | 2259 | 0.69 | 1.44 |
| Centrarchidae | |||||||
| Black crappie | Pomoxis nigromaculatus | 100 | 396 | 9 | 960 | 0.59 | 1.72 |
| Bluegill | Lepomis macrochirus | 80 | 254 | 5 | 572 | 0.50 | 2.02 |
| Green sunfish | Lepomis cyanellus | 61 | 226 | 5 | 260 | 0.40 | 2.40 |
| Largemouth bass | Micropterus salmoides | 150 | 520 | 40 | 2630 | 0.67 | 1.50 |
| Pumpkinseed | Lepomis gibbosus | 53 | 260 | 3 | 317 | 0.53 | 1.93 |
| Smallmouth bass | Micropterus dolomieu | 151 | 561 | 27 | 3500 | 0.60 | 1.67 |
| Cottidae | |||||||
| Columbia slimy sculpin | Uranidea sp. cf. cognata ‡ | 90 | 138 | 6 | 43 | 0.54 | 1.63 |
| Rocky mountain sculpin | Uranidea sp. cf. bairdii ‡ | 90 | 597 | 6 | 2767 | 0.66 | 1.53 |
| Cyprinidae | |||||||
| Common carp | Cyprinus carpio | 200 | 851 | 90 | 10,610 | 0.69 | 1.45 |
| Esocidae | |||||||
| Northern Pike | Esox lucius | 102 | 1118 | 5 | 13,617 | 0.62 | 1.61 |
| Tiger muskellunge | Esox masquinongy x lucius | 254 | 1270 | 68 | 14,515 | 0.71 | 1.45 |
| Hiodontidae | |||||||
| Goldeye | Hiodon alosoides | 100 | 505 | 9 | 1501 | 0.68 | 1.48 |
| Ictaluridae | |||||||
| Black bullhead | Ameiurus melas | 130 | 353 | 20 | 850 | 0.60 | 1.66 |
| Stonecat | Noturus flavus | 90 | 269 | 5 | 272 | 0.56 | 1.78 |
| Yellow bullhead | Ameiurus natalis | 124 | 360 | 20 | 750 | 0.71 | 1.41 |
| Leuciscidae | |||||||
| Flathead chub | Platygobio gracilis | 100 | 272 | 9 | 213 | 0.40 | 2.37 |
| Golden shiner | Notemigonus crysoleucas | 71 | 452 | 5 | 1021 | 0.52 | 1.91 |
| Lake chub | Couesius plumbeus | 50 | 183 | 2 | 73 | 0.41 | 2.63 |
| Longnose dace | Rhinichthys cataractae | 110 | 168 | 10 | 54 | 0.54 | 2.22 |
| Northern pikeminnow | Ptychocheilus oregonensis | 250 | 642 | 92 | 2988 | 0.67 | 1.48 |
| Peamouth | Mylocheilus caurinus | 102 | 414 | 7 | 778 | 0.68 | 1.47 |
| Redside shiner | Richardsonius balteatus | 90 | 193 | 4 | 70 | 0.54 | 2.01 |
| Utah chub | Gila atraria | 109 | 462 | 14 | 1061 | 0.63 | 1.61 |
| Lotidae | |||||||
| Burbot | Lota lota | 200 | 914 | 36 | 4649 | 0.57 | 1.77 |
| Percidae | |||||||
| Sauger | Sander canadensis | 84 | 676 | 5 | 3400 | 0.64 | 1.62 |
| Walleye | Sander vitreus | 150 | 856 | 18 | 7475 | 0.70 | 1.44 |
| Yellow perch | Perca flavescens | 101 | 569 | 9 | 3470 | 0.59 | 1.68 |
| Polyodontidae | |||||||
| Paddlefish † | Polyodon spathula | ||||||
| Overall | 711 | 1473 | 4990 | 56,246 | 0.68 | 1.46 | |
| Female | 914 | 1473 | 12,247 | 56,246 | 0.72 | 1.37 | |
| Male | 711 | 1143 | 4990 | 25,855 | 0.73 | 1.39 | |
| Salmonidae | |||||||
| Arctic grayling | Thymallus arcticus | 150 | 477 | 23 | 1139 | 0.56 | 1.82 |
| Brook trout | Salvelinus fontinalis | 120 | 562 | 11 | 1846 | 0.59 | 1.69 |
| Brown trout | Salmo trutta | ||||||
| Lentic | 140 | 777 | 27 | 6056 | 0.63 | 1.59 | |
| Lotic | 140 | 820 | 20 | 6000 | 0.68 | 1.46 | |
| Bull trout | Salvelinus confluentus | 120 | 900 | 10 | 7306 | 0.66 | 1.53 |
| Cisco | Coregonus artedi | 102 | 463 | 9 | 918 | 0.63 | 1.57 |
| Golden trout | O. mykiss aguabonita | 124 | 566 | 23 | 1724 | 0.51 | 1.94 |
| Kokanee | Oncorhynchus nerka | 121 | 676 | 14 | 2957 | 0.69 | 1.46 |
| Lake trout | Salvelinus namaycush | 280 | 1110 | 145 | 11,225 | 0.67 | 1.49 |
| Lake whitefish | Coregonus clupeaformis | 100 | 650 | 5 | 3098 | 0.65 | 1.57 |
| Mountain whitefish | Prosopium williamsoni | 140 | 577 | 16 | 2014 | 0.65 | 1.55 |
| Pygmy whitefish | Prosopium coulterii | 90 | 235 | 4 | 116 | 0.70 | 1.41 |
| Rainbow trout | Oncorhynchus mykiss | ||||||
| Lentic | 122 | 808 | 18 | 6144 | 0.63 | 1.60 | |
| Lotic | 120 | 829 | 13 | 7469 | 0.67 | 1.50 | |
| Westslope cutthroat trout | O. clarkii lewisi | ||||||
| Lentic | 130 | 597 | 15 | 2400 | 0.67 | 1.50 | |
| Lotic | 130 | 546 | 14 | 1735 | 0.64 | 1.56 | |
| Yellowstone cutthroat trout | O. clarkii bouvieri | ||||||
| Lentic | 132 | 632 | 14 | 2500 | 0.55 | 1.82 | |
| Lotic | 131 | 608 | 16 | 2415 | 0.67 | 1.48 | |
| Sciaenidae | |||||||
| Freshwater drum | Aplodinotus grunniens | 114 | 680 | 20 | 4800 | 0.67 | 1.53 |
Table 2.
Parameter estimates for a′ and b used for W′ for 51 Montana fish species and three subspecies with 95% credible intervals in parentheses. Equation parameters for metric units are in millimeters and grams and values for English units are in inches and pounds. All lengths are reported as total length except paddlefish, noted by †, that is measured from eye to fork of caudal fin. Asterisks (*) on minimal total length indicate values obtained from standard-weight, Ws, equations [2]. Cottidae species are noted with a ‡ as they are being described as new species. Columbia slimy sculpin were previously referred to as slimy sculpin Cottus cognatus and Rocky Mountain sculpin were previously referred to as mottled sculpin C. bairdii.
Table 2.
Parameter estimates for a′ and b used for W′ for 51 Montana fish species and three subspecies with 95% credible intervals in parentheses. Equation parameters for metric units are in millimeters and grams and values for English units are in inches and pounds. All lengths are reported as total length except paddlefish, noted by †, that is measured from eye to fork of caudal fin. Asterisks (*) on minimal total length indicate values obtained from standard-weight, Ws, equations [2]. Cottidae species are noted with a ‡ as they are being described as new species. Columbia slimy sculpin were previously referred to as slimy sculpin Cottus cognatus and Rocky Mountain sculpin were previously referred to as mottled sculpin C. bairdii.
| Intercept (a′) | Minimal Total Length | |||||
|---|---|---|---|---|---|---|
| Species | Scientific Name | Metric | English | Slope (b) | (mm) | n |
| Acipenseridae | ||||||
| Pallid sturgeon | Scaphirhynchus albus | −6.397 (−6.501, −6.292) | −4.377 (−4.428, −4.327) | 3.329 (3.290, 3.367) | 320 | 464 |
| White sturgeon | Acipenser transmontanus | −6.692 (−6.895, −6.487) | −4.497 (−4.604, −4.390) | 3.454 (3.384, 3.522) | 700 * | 328 |
| Catostomidae | ||||||
| Bigmouth buffalo | Ictiobus cyprinellus | −5.130 (−5.229, −5.031) | −3.401 (−3.450, −3.352) | 3.122 (3.086, 3.157) | 150 * | 312 |
| Blue sucker | Cycleptus elongatus | −5.850 (−6.068, −5.631) | −3.903 (−4.014, −3.792) | 3.277 (3.200, 3.353) | 240 * | 807 |
| Largescale sucker | Catostomus macrocheilus | −5.134 (−5.146, −5.122) | −3.509 (−3.514, −3.504) | 3.048 (3.043, 3.053) | 110 | 26,035 |
| Longnose sucker | Catostomus catostomus | −5.012 (−5.020, −5.004) | −3.433 (−3.437, −3.430) | 3.015 (3.012, 3.018) | 90 | 43,717 |
| Mountain sucker | Catostomus platyrhynchus | −4.633 (−4.748, −4.517) | −3.267 (−3.307, −3.226) | 2.864 (2.810, 2.917) | 100 | 2030 |
| River carpsucker | Carpiodes carpio | −5.134 (−5.159, −5.109) | −3.434 (−3.445, −3.422) | 3.102 (3.092, 3.111) | 130 * | 14,017 |
| Shorthead redhorse | Moxostoma macrolepidotum | −4.964 (−4.976, −4.952) | −3.407 (−3.413, −3.402) | 2.999 (2.994, 3.004) | 100 * | 26,877 |
| Smallmouth buffalo | Ictiobus bubalus | −4.621 (−4.675, −4.567) | −3.157 (−3.184, −3.130) | 2.933 (2.914, 2.953) | 200 * | 2945 |
| White sucker | Catostomus commersonii | −5.243 (−5.248, −5.237) | −3.512 (−3.514, −3.510) | 3.123 (3.121, 3.125) | 100 * | 134,086 |
| Centrarchidae | ||||||
| Black crappie | Pomoxis nigromaculatus | −5.150 (−5.173, −5.128) | −3.387 (−3.396, −3.378) | 3.147 (3.137, 3.157) | 100 * | 16,650 |
| Bluegill | Lepomis macrochirus | −5.435 (−5.502, −5.368) | −3.388 (−3.410, −3.365) | 3.349 (3.317, 3.380) | 80 * | 4770 |
| Green sunfish | Lepomis cyanellus | −4.702 (−4.820, −4.584) | −3.155 (−3.194, −3.117) | 2.993 (2.936, 3.049) | 60 * | 1613 |
| Largemouth bass | Micropterus salmoides | −5.178 (−5.217, −5.140) | −3.407 (−3.423, −3.391) | 3.152 (3.136, 3.168) | 150 * | 4448 |
| Pumpkinseed | Lepomis gibbosus | −4.998 (−5.050, −4.946) | −3.220 (−3.237, −3.203) | 3.157 (3.132, 3.182) | 50 * | 5164 |
| Smallmouth bass | Micropterus dolomieu | −5.302 (−5.321, −5.282) | −3.474 (−3.482, −3.466) | 3.192 (3.184, 3.200) | 150 * | 19,325 |
| Cottidae | ||||||
| Columbia slimy sculpin | Uranidea sp. cf. cognata ‡ | −5.488 (−6.065, −4.907) | −3.529 (−3.701, −3.356) | 3.286 (2.994, 3.574) | 90 | 260 |
| Rocky mountain sculpin | Uranidea sp. cf. bairdii ‡ | −5.012 (−5.020, −5.004) | −3.433 (−3.437, −3.430) | 3.015 (3.012, 3.018) | 80 | 43,717 |
| Cyprinidae | ||||||
| Common carp | Cyprinus carpio | −4.787 (−4.800, −4.773) | −3.280 (−3.287, −3.273) | 2.964 (2.959, 2.969) | 200 * | 33,650 |
| Esocidae | ||||||
| Northern pike | Esox lucius | −5.618 (−5.636, −5.600) | −3.839 (−3.848, −3.830) | 3.158 (3.151, 3.164) | 100 * | 17,788 |
| Tiger muskellunge | Esox masquinongy x lucius | −6.009 (−6.107, −5.911) | −4.041 (−4.090, −3.993) | 3.292 (3.257, 3.327) | 240 * | 365 |
| Hiodontidae | ||||||
| Goldeye | Hiodon alosoides | −4.834 (−4.857, −4.810) | −3.399 (−3.409, −3.388) | 2.913 (2.903, 2.922) | 100 | 26,257 |
| Ictaluridae | ||||||
| Black bullhead | Ameiurus melas | −5.174 (−5.233, −5.115) | −3.401 (−3.424, −3.378) | 3.154 (3.128, 3.179) | 130 * | 3157 |
| Stonecat | Noturus flavus | −5.038 (−5.126, −4.948) | −3.467 (−3.501, −3.433) | 3.009 (2.970, 3.049) | 90 | 2609 |
| Yellow bullhead | Ameiurus natalis | −5.442 (−5.531, −5.353) | −3.528 (−3.564, −3.491) | 3.254 (3.217, 3.291) | 60 * | 1462 |
| Leuciscidae | ||||||
| Flathead chub | Platygobio gracilis | −4.453 (−4.561, −4.345) | −3.257 (−3.294, −3.219) | 2.743 (2.693, 2.793) | 100 | 3146 |
| Golden shiner | Notemigonus crysoleucas | −4.261 (−4.398, −4.123) | −3.117 (−3.166, −3.067) | 2.706 (2.642, 2.768) | 50 * | 454 |
| Lake chub | Couesius plumbeus | −4.760 (−5.002, 4.517) | −3.331 (−3.402, −3.260) | 2.908 (2.785, 3.031) | 50 | 275 |
| Longnose dace | Rhinichthys cataractae | −4.703 (−5.207, 4.197) | −3.338 (−3.506, −3.169) | 2.863 (2.623, 3.102) | 110 | 303 |
| Northern pikeminnow | Ptychocheilus oregonensis | −5.630 (−5.655, 5.604) | −3.753 (−3.765, −3.742) | 3.227 (3.217, 3.237) | 250 * | 10,663 |
| Peamouth | Mylocheilus caurinus | −5.552 (−5.569, 5.536) | −3.718 (−3.725, −3.711) | 3.197 (3.190, 3.204) | 100 | 45,476 |
| Redside shiner | Richardsonius balteatus | −5.864 (−5.997, 5.730) | −3.723 (−3.768, −3.677) | 3.416 (3.353, 3.478) | 90 | 1463 |
| Utah chub | Gila atraria | −5.155 (−5.176, 5.133) | −3.444 (−3.453, −3.436) | 3.109 (3.100, 3.118) | 90 * | 15,394 |
| Lotidae | ||||||
| Burbot | Lota lota | −4.944 (−4.968, 4.920) | −3.540 (−3.551, −3.528) | 2.891 (2.882, 2.900) | 200 * | 14,913 |
| Percidae | ||||||
| Sauger | Sander canadensis | −5.606 (−5.628, 5.583) | −3.774 (−3.785, −3.764) | 3.195 (3.186, 3.204) | 70 * | 15,293 |
| Walleye | Sander vitreus | −5.688 (−5.695, 5.681) | −3.780 (−3.784, −3.777) | 3.249 (3.247, 3.252) | 150 * | 73,814 |
| Yellow perch | Perca flavescens | −5.507 (−5.518, 5.496) | −3.573 (−3.578, −3.569) | 3.268 (3.263, 3.273) | 100 * | 94,512 |
| Polyodontidae | ||||||
| Paddlefish † | Polyodon spathula | |||||
| Overall | −7.010 (−7.090, 6.929) | −4.424 (−4.467, −4.381) | 3.732 (3.705, 3.758) | 280 * | 7200 | |
| Female | −5.274 (−5.481, 5.066) | −3.480 (−3.592, −3.367) | 3.169 (3.101, 3.236) | 280 * | 3785 | |
| Male | −4.530 (−4.692, 4.366) | −3.119 (−3.205, −3.032) | 2.896 (2.841, 2.950) | 280 * | 3,379 | |
| Salmonidae | ||||||
| Arctic grayling | Thymallus arcticus | −5.696 (−5.721, 5.671) | −3.781 (−3.792, −3.770) | 3.254 (3.244, 3.265) | 150 * | 14,668 |
| Brook trout | Salvelinus fontinalis | −5.248 (−5.256, 5.240) | −3.527 (−3.530, −3.524) | 3.117 (3.113, 3.120) | 120 * | 84,064 |
| Brown trout | Salmo trutta | |||||
| Lentic | −5.133 (−5.161, 5.105) | −3.510 (−3.523, −3.498) | 3.046 (3.035, 3.057) | 140 * | 6381 | |
| Lotic | −4.783 (−4.786, 4.781) | −3.353 (−3.354, −3.352) | 2.910 (2.909, 2.911) | 140 * | 841,787 | |
| Bull trout | Salvelinus confluentus | −5.125 (−5.133, 5.117) | −3.525 (−3.528, −3.522) | 3.030 (3.027, 3.034) | 120 * | 26,930 |
| Cisco | Coregonus artedi | −5.513 (−5.529, −5.498) | −3.677 (−3.684, −3.671) | 3.198 (3.192, 3.205) | 100 * | 31,244 |
| Golden trout | O. mykiss aguabonita | −4.713 (−4.834, −4.591) | −3.326 (−3.377, −3.274) | 2.879 (2.829, 2.928) | 120 * | 972 |
| Kokanee | Oncorhynchus nerka | −5.206 (−5.217, −5.195) | −3.549 (−3.554, −3.544) | 3.071 (3.067, 3.075) | 120 * | 56,706 |
| Lake trout | Salvelinus namaycush | −5.301 (−5.326, −5.276) | −3.635 (−3.647, −3.622) | 3.078 (3.068, 3.087) | 280 * | 9714 |
| Lake whitefish | Coregonus clupeaformis | −5.834 (−5.847, −5.820) | −3.858 (−3.864, −3.853) | 3.297 (3.292, 3.302) | 100 * | 17,893 |
| Mountain whitefish | Prosopium williamsoni | −5.226 (−5.234, −5.219) | −3.559 (−3.562, −3.556) | 3.079 (3.076, 3.081) | 140 * | 170,721 |
| Pygmy whitefish | Prosopium coulterii | −6.044 (−6.098, −5.990) | −3.916 (−3.934, −3.898) | 3.406 (3.380, 3.432) | 90 | 2965 |
| Rainbow trout | Oncorhynchus mykiss | |||||
| Lentic | −4.906 (−4.926, −4.886) | −3.398 (−3.407, −3.389) | 2.965 (2.957, 2.973) | 120 * | 18,967 | |
| Lotic | −4.841 (−4.844, −4.839) | −3.370 (−3.371, −3.369) | 2.939 (2.938, 2.940) | 120 * | 780,901 | |
| Westslope cutthroat trout | O. clarkii lewisi | |||||
| Lentic | −5.322 (−5.344, −5.301) | −3.578 (−3.587, −3.569) | 3.133 (3.124, 3.142) | 130 * | 12,006 | |
| Lotic | −5.086 (−5.092, −5.080) | −3.480 (−3.483, −3.478) | 3.034 (3.032, 3.037) | 130 * | 94,520 | |
| Yellowstone cutthroat trout | O. clarkii bouvieri | |||||
| Lentic | −5.260 (−5.292, −5.227) | −3.577 (−3.591, −3.562) | 3.089 (3.076, 3.102) | 130 * | 11,308 | |
| Lotic | −4.958 (−4.967, −4.949) | −3.421 (−3.425, −3.417) | 2.985 (2.981, 2.989) | 130 * | 44,958 | |
| Sciaenidae | ||||||
| Freshwater drum | Aplodinotus grunniens | −5.161 (−5.193, −5.130) | −3.454 (−3.468, −3.439) | 3.107 (3.094, 3.119) | 100 * | 6155 |
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MDPI and ACS Style
Eckelbecker, R.W.; Heili, N.M.; Guy, C.S.; Schmetterling, D.A. Relative Condition Parameters for Fishes of Montana, USA. Fishes 2023, 8, 28. https://doi.org/10.3390/fishes8010028
AMA Style
Eckelbecker RW, Heili NM, Guy CS, Schmetterling DA. Relative Condition Parameters for Fishes of Montana, USA. Fishes. 2023; 8(1):28. https://doi.org/10.3390/fishes8010028
Chicago/Turabian StyleEckelbecker, Robert W., Nathaniel M. Heili, Christopher S. Guy, and David A. Schmetterling. 2023. "Relative Condition Parameters for Fishes of Montana, USA" Fishes 8, no. 1: 28. https://doi.org/10.3390/fishes8010028
