Big fish stories: analysis of historical newspaper data on size of lake sturgeon (Acipenser fulvescens) in the Lake Michigan basin.
Old newspapers (1850-1915) in the Lake Michigan basin were surveyed for reports of large lake sturgeon ([greater than or equal to] 100 pounds = 45.4 kg). Records of large fish were obtained from throughout the basin. To assess the accuracy of reported measurements, reported weights associated with reported lengths were compared to weights predicted by a weight-length regression developed for a large sample of fish from Lake Winnebago. Although there were a few obvious or likely outliers in the historical Lake Michigan data set, reported and predicted weights were not significantly different. Moreover, although the mean magnitude of deviations between reported and predicted weights, expressed as a proportion of predicted weight, was substantial, it was comparable to natural variability among lake sturgeon due to the effects of differences between sexes, locations, times of year, and reproductive status.
A fish, if such it may be called, was speared with pevies by some log-runners at work on the Sauble river, above the bridge that spans the stream, on Saturday last. In general apperance [sic] it resembaled [sic] a sucker, and but for its colossal dimensions could be taken for such. It measured 18 feet in length by 80 inches in circumferance [sic] in the thickest part. The like of it was never before seen in the stream, and those who viewed it are at a loss what to call it. (St. Joseph Herald & Traveler, May 1, 1880).
There is something about fish which stimulates tall tales, and sturgeon, being the largest of all fish except for a few of the largest sharks, are responsible for their share of "fish stories" (Harkness and Dymond, 1961).
Public and scientific fascination with large freshwater fishes is not new, although widespread concern for the welfare of the freshwater megafauna is relatively recent (e.g., Stone 2007). One of the North American "megafishes" listed by Stone (2007) is the lake sturgeon (Acipenser fulvescens). Like other sturgeon species, the lake sturgeon has declined over much of its range, a decline that began in the late 1800s (Tower 1909), but it has caught the attention of the general public (Schmitt Kline et al. 2009).
Harkness and Dytnond (1961) provided a list of all lake sturgeon over 100 pounds (45.4 kg) in weight for which they had records. Most of their 37 records were obtained from newspaper accounts, and most were post-1920. Only one was caught in the Lake Michigan basin. Becker (1983) provided a few additional records of large lake sturgeon, and a 1903 photograph of a very large specimen from Manitoba, said to be over 400 pounds (181.4 kg), appeared in Stewart and Watkinson (2004).
During an attempt to reconstruct the original geographical distribution and relative abundance of lake sturgeon in tributaries of Lake Michigan, old newspapers (1850-1915) were surveyed for accounts of sturgeon captured by sport and commercial fishers. The purpose of the present report is to provide records of large lake sturgeon ([greater than or equal to] 100 pounds = 45.4 kg) obtained during that survey. Cochran and Elliott (2012) discussed the efficacy of using the newspaper record for obtaining biologically relevant data on sturgeon. Because of the well known tendency for fish sizes to be exaggerated in popular accounts, a second objective of this study was to assess the veracity of newspaper records by examining relationships between reported weights and lengths. If reported weights and lengths are accurate, they should lie close to a weight-length curve that more or less approximates a cube law relationship (Froese 2006).
Newspapers published in cities and towns in the Lake Michigan drainage basin were surveyed, primarily on microfilm. These included 22 newspapers in 12 Wisconsin localities, 20 newspapers in eight Michigan localities, and two newspapers in Indiana. Newspapers varied in their frequency of appearance (most appeared weekly) and in the number of years that they were published. Surveys emphasized the period 1850-1915, during which time lake sturgeon populations in the Great Lakes declined precipitously to the point that catches of individual sturgeon were often newsworthy and described in some detail (Cochran and Elliott 2012). All mentions of lake sturgeon were recorded. Cochran and Elliott (2012) reported that over 90% of known records were recovered by technicians involved in the survey.
To provide for comparison with the data of Harkness and Dymond (1961), I used records of sturgeon with reported weights [greater than or equal to] 100 pounds (45.4 kg). These records were plotted as closely as possible on a map of the Lake Michigan basin. The subset of records for which both length and weight were reported were used to investigate whether reported measurements were consistent with a known weight-length relationship. As a basis for comparison, I used the following equation derived from data for Lake Winnebago lake sturgeon (Bruch et al. 2011):
W = 0.00140*([L.sup.3,307])
where W is weight in g and L is total length in cm. I used this equation to predict weight for each reported historical length and then used a paired t-test to compare predicted and reported historical weights. Note that Bruch et al. (2011) found that the weight-length relationship in Lake Winnebago lake sturgeon is best described in two stanzas based on total length, with one equation for young juveniles (first stanza) and separate equations for males and females >71 cm in total length (second stanza). However, because the sex of sturgeon in the historical newspaper accounts was rarely reported, I used the equation reported by Bruch et al. (2011) for both sexes pooled. Separate analyses were conducted for the data set of Harkness and Dymond (1961) and the Lake Michigan basin data set collected during the present study. Additionally, a set of 10 modern (1953-2007) newspaper records (Green Bay PresS'Gazette, 14 February 2009), purported to be the largest specimens taken in the Lake Winnebago late winter spear fishery, was subjected to the same analysis.
To assess whether reported weights and lengths in the Harkness and Dymond (1961) and Lake Michigan basin data sets approximated cubic law relationships, independent of the previous analysis, simple linear least squares regressions of In(weight) on In(length) were used to estimate the exponents of the weight-length curves. It was expected that slopes would be approximately equal to 3.
Accounts of lake sturgeon appeared in 29 of 44 newspapers. Reports of lake sturgeon [greater than or equal to] 100 pounds (45.4 kg) during the period 1850-1915 (see Appendix) were scattered throughout the Lake Michigan basin (Figure 1). Reported weights (Figure 2) ranged from 45.4 kg (the arbitrary minimum for data to be selected) to 216.8 kg. Reported lengths (Figure 3) ranged from 122 cm (4 feet) to 361 cm (11 feet, 10 inches). Both length extremes are questionable. The lower length would typically be associated with a weight much less than 100 pounds, while the greater extreme would be associated with a much heavier weight than what was reported (see below).
In the historical Lake Michigan data set, there were 22 records for which both length and weight were reported. However, four records were excluded because either length or weight was specified in a vague manner (e.g., "about six feet" or "almost seven feet long"). Reported weight and weight predicted by the regression of Bruch et al. (2011) were highly correlated (r = 0.657, p = 0.003), even with the inclusion of one obvious outlier (Figure 4). Reported and predicted weights were not significantly different, regardless of whether the outlier was included (paired t = -0.607, df = 17, p = 0.552) or excluded (paired t = 0.0.532, df = 16, p = 0.608), although the sign of the mean difference depended on the outlier. The mean difference between reported and predicted weights, expressed as a proportion of the predicted weight, was 0.040 with the outlier included and -0.064 with the outlier excluded. The mean proportional difference between reported and predicted weights with sign ignored (i.e., absolute value) was 0.427 with the outlier included and 0.345 with the outlier excluded.
In the data set of Harkness and Dymond (1961), there were 20 records for which both length and weight were reported, but one was excluded ("about 8 feet long"). Reported lengths ranged from 168 cm to 241 cm, and reported weights ranged from 58.5 kg to 140.6 kg. Reported weight and weight predicted by the regression of Bruch et al. (2011) were highly correlated (r = 0.785, p = 0.000). Reported weights tended to be greater than predicted weights (Figure 5), and the difference was significant (paired t = 7.295, df = 18, p = 0.000), even though mean absolute difference was less than for the historical Lake Michigan data set (i.e., the points were closer to the line of equality). The mean difference between reported and predicted weights, expressed as a proportion of the predicted weight, was -0.265.
The 10 lake sturgeon in the modern data set from the Lake Winnebago spear fishery ranged in reported length from 188 cm to 216 cm and in reported weight from 70.8 kg to 85.3 kg (Figure 6). Reported and predicted weights were not significantly correlated (r = 0.382, p = 0.276), but in all cases reported weight exceeded predicted weight (paired t = 8.091, df = 9, p = 0.000). The mean difference between reported and predicted weights, expressed as a proportion of the predicted weight, was -0.361.
Relationships between reported weight and reported length did not assume a cube law relationship with an exponent approximately equal to 3 for either of the historical data sets. For the Lake Michigan basin data set, exponents were 1.267 and 1.320 when the outlier was included or excluded, respectively. For the data set of Harkness and Dymond (1961), the exponent was 1.875.
Judging from newspaper reports, large lake sturgeon could be encountered throughout the Lake Michigan basin during the period 1850-1915 (Figure 1), at least until stocks declined (Tower 1909; Cochran and Elliott 2012). However, there are reasons why sizes reported in old newspaper stories might be questioned. Before considering the effects of human error or exaggeration on reported measurements, it is important to consider the context of natural variability.
Natural variability in weight-length relationships of lake sturgeon arises not only from individual variation in condition, but also from the effects of differences between males and females, reproductive stage, time of year, and geographic location. For example, Bruch et al. (2011, their Figure 2) depicted the substantial variability in weight-length data between and within sexes of Lake Winnebago sturgeon. Their regressions for weight-length relationships of female and male sturgeon can be used to predict that, at a length of 2 m, a female will weigh on average 7.85 % more than a male. Harkness and Dymond (1961) depicted weight-length curves for sturgeon from Lake Nipigon and Lake St. Francis that predict that, at a length of 1.15 m, the latter will be on average 40% heavier than the former. Note that in each of these cases, variability among individuals within groups can lead to even greater variability among individuals chosen from pools that include both sexes or both locations. This sort of variability would contribute to scatter about the line of equality in a plot of predicted weight versus reported weight resulting from an analysis such as conducted in the present study (e.g., Figure 4). This is especially true in a case, such as the present study, when the sample of sturgeon is constituted of fish captured over a broad geographic area over a long period of time.
Although weight-length data are expected to approximate cubic law relationships (Froese 2006), small samples with great scatter, such as the historical data sets used in the present study, may result in regression-based estimates of the weight-length exponent that are much lower than the values of 3 or greater that are more typical. The modern data set (Figure 6) would provide another example, with six sturgeon approximately 200 cm in length ([+ or -] 2 cm) varying in weight over a range of 15 kg.
Two anthropogenic sources of error might lead to questionable historical reports of sturgeon sizes. First, it might have been difficult to measure large sturgeon accurately, especially for weight. Inaccuracy in measurements would contribute to variability about the expected line of equality in Figures 4 and 5 (in addition to natural variability due to the effects of sex, reproductive condition, time of year, etc.). Second, a tendency to exaggerate, as suggested by Harkness and Dymond (1961), might lead to sensationalism of the sizes of individual sturgeon in newspaper accounts. Indeed, in the present study, newspaper accounts included such words as "whale," "elephantine," and "monstrous." A tendency to exaggerate either length or weight would result in systematic bias to one side or the other of the line of equality in Figures 4 and 5, as would any tendency for records to include primarily fish of one sex or fish caught during a time of year when they were relatively heavy or light. An example of the latter is provided by the modern newspaper "sample" of 10 large sturgeon from the Lake Winnebago late winter spear fishery; this sample likely consisted of relatively heavy gravid females.
Use of Bruch et al.'s (2011) weight-length relationship for Lake Winnebago lake sturgeon as a basis for comparison with data for sturgeon from a broader range of locations might seem arbitrary. However, 8 of 22 records in the historical Lake Michigan data set were from the Lake Winnebago system. Moreover, Bruch et al. (2011) suggested that the condition or plumpness of Lake Winnebago lake sturgeon was close to the average for North American fish. I obtained qualitatively and statistically similar results when I repeated all comparisons with the Lake Michigan historical data set, the data set of Harkness and Dymond (1961), and the modern data from the Lake Winnebago spear fishery using Bruch et al.'s (2011) regressions for Lake Winnebago females > 71 cm and for gravid females with fully developed eggs.
In the historical data set for the Lake Michigan basin, there was one obvious outlier (Figure 4), a fish reported in the Manistique Pioneer-Tribune (3 June 1898) as having been caught in the bay off Thompson, Michigan. In this case it appeared that the reported length, 11 ft 10 in (361 cm), was greatly exaggerated, so that the reported weight, 314 pounds (142 kg), even though exceptional, was much less than the predicted weight of 882 pounds (400 kg). Otherwise, there appeared to be no consistent exaggeration of reported lengths or weights, with a roughly even scatter of points about the line of equality in Figure 4- Although mean absolute deviations between reported and predicted weights were large, they fell within a range that might be expected due to natural variability.
In contrast, the data provided by Harkness and Dymond (1961) displayed a tendency for reported weights to exceed predicted weights (Figure 5). This might have resulted from a systematic exaggeration of reported weights, a systematic underestimation of reported lengths, or from a tendency to report fish captured at a time of year when they are relatively heavy (e.g., pre-spawning females heavy with eggs). Becker (1983) noted that about one-fifth of a ripe female's weight will be roe. Two reports from the Lake Michigan basin data set mentioned large masses of eggs in female fish: a 178-pound (80.7 kg) fish that contained 46 pounds (20.9 kg) of eggs (Holland City News, 17 May 1890) and an 8-foot, 125-pound (56.7 kg) fish that contained 20.5 pounds (9.3 kg) of eggs (De Pere News, 3 June and 17 July 1912). The reported weight of the latter fish is much less than the 109.7 kg predicted by Bruch et al. (2011), and even further from the weight predicted by their equation for females (112.1 kg), and it would seem to be a case in which length rather than weight was exaggerated. However, because the data set from Harkness and Dymond (1961) included fish captured from throughout the year, it is not likely that ripe females contributed disproportionately to the tendency for reported weights to exceed predicted weights.
A comparison with the Lake Michigan basin data set suggests the possibility that measurements were more accurate by the time that the fish reported by Harkness and Dymond (1961) were captured. Although it was expected that weight would be reported less accurately than length, there is evidence that length was overestimated in some cases in the Lake Michigan basin data set. When sturgeon were harvested commercially, weight was probably more important than length.
Perhaps more than any other freshwater fish, the lake sturgeon may be considered part of the "charismatic megafauna" that has spurred so many conservation efforts. Results of this study indicate that at one time, no one in the Lake Michigan basin lived very far from lake sturgeon of large size. It is hoped that the list of large sturgeon records tied to specific localities provided in the Appendix will serve as a source for examples to inspire local efforts to restore sturgeon populations.
This research was supported in part by Grant No. 2002.256 from the Great Lakes Fishery Trust. The librarians at the Saint Mary's University Fitzgerald Library helped arrange for loans of old news papers on microfilm. I thank students Emily Bartusek, Chad Brusky, Jennifer Cochran, Bridget Emmett, Sarah Kraszewski, William Martin, and Brendon Panke for assistance in surveying old newspapers or sorting records and Kevin Olson for preparing the map.
Saint Mary's University of Minnesota
Becker, G. C. 1983. Fishes of Wisconsin. Madison: University of Wisconsin Press.
Bruch, R. M., K. K. Kamke, and T. Haxton. 2011. "Use of a Modified Form Factor to Compare Condition among North American Sturgeon Stocks." Journal of Applied Ichthyology 27 (Supplement 2): 34-40.
Cochran, P. A., and R. F. Elliott. 2012. "Newspapers as Sources of Historical Information about Lake Sturgeon (Acipenser fulvescens Rafinesque, 1817)." Archives of Natural History 39: 136-146.
Froese, R. 2006. "Cube law, Condition Factor and Weight-Length Relationships: History, Meta-Analysis and Recommendations." Journal of Applied Ichthyology 22: 241-253.
Harkness, J. K. H., and J. R. Dymond. 1961. "The Lake Sturgeon: the History of its Fishery and Problems of Conservation." Toronto: Ontario Department of Lands and Forests, Fish and Wildlife Branch.
Schmitt Kline, K., R. M. Bruch, and F. P. Binkowski, with photographs by B. Rashid. 2009. People of the Sturgeon: Wisconsin's Love Affair with an Ancient Fish. Madison: Wisconsin Historical Society Press.
Stone, R. 2007. "The Last of the Leviathans." Science 316: 1684-1688.
Stewart, K. W., and D. A. Watkinson. 2004- The Freshwater Fishes of Manitoba. Winnipeg: University of Manitoba Press.
Tower, W.S. 1909. "The Passing of the Sturgeon: a Case of the Unparalleled Extermination of a Species." Popular Science Monthly 73: 361-371.
Old newspaper records of sturgeon over 100 pounds that were captured in the Lake Michigan basin during 1850-1915. For records from Lake Michigan proper, the nearest city or town is indicated. Otherwise the river in which a fish was caught is identified. For the purposes of this list, the Upper and Lower Fox Rivers are separated by Lake Winnebago. Weights are indicated in pounds, and lengths are indicated when they were provided.
April 20, 1853, Milwaukee Journal Sentinel, Milwaukee River, over 100 (6 1/2 feet).
June 9, 1854, Milwaukee Journal Sentinel, Fox River, 189.
April 2, 1868, Niles Republican, St. Joseph River, 100 (6 feet).
April 16, 1868, Niles Republican, St. Joseph River, two fish: one 186 (7 feet) and the other over 300.
May 7, 1868, Niles Republican, St. Joseph River, 225 (7 1/2 feet).
June 2, 1870, Oshkosh Northwestern, Lake Winnebago, 108 1/2 (6 feet, 3 inches).
March 20, 1871, Oshkosh Northwestern, Lake Winnebago, 151 (5 feet, 7 inches).
March 13, 1872, Milwaukee Journal Sentinel, Lake Winnebago, 101.
March 13, 1873, Oshkosh Northwestern, Lake Winnebago, 142.
March 24, 1873, The Evening Wisconsin, Upper Fox River, 140.
May 9, 1873, The Evening Wisconsin, Lake Winnebago, 3 fish over 100.
January 10, 1874, The Milwaukee Journal Sentinel, Sheboygan, 120.
February 6, 1874, Milwaukee Journal Sentinel, Lake Winnebago--140.
March 15, 1875, The Milwaukee Journal Sentinel, Menomonee River, Milwaukee, 100 (4 feet).
May 22, 1875, De Pere News, Wolf River, 125.
June 11, 1875, Kewaunee Enterprise, Wolf River, 123.
June 19, 1875, Oconto County Reporter, Green Bay of Lake Michigan, 478 (9 feet, 2 inches).
June 30, 1876, The Milwaukee Journal Sentinel, Milwaukee, 100 (about 6 feet).
May 3, 1877, Oshkosh Northwestern, Lake Winnebago, 100.
June 2, 1877, Manistee Advocate, Pere Marquette River, sometimes as much as 100 pounds.
April 26, 1878, Muskegon Chronicle, Whitehall, 100 (over 5 feet).
April 14, 1881, Fond du Lac Journal, Lake Winnebago, 297 (9 feet).
May 27, 1881, Kewaunee Enterprise, Lake Winnebago, 100 (over 6 feet).
September 17, 1881, De Pere News, Racine, 169 (5 feet, 6 inches).
November 2, 1882, Oshkosh Northwestern, Lake Buttes des Morts, 125 (6 1/2 feet).
July 2, 1885, Grand Traverse Herald, Traverse City, 110.
April 29, 1886, Oshkosh Northwestern, Upper Fox River, Berlin, 125.
May 12, 1887, Oshkosh Northwestern, Upper Fox River, Berlin, 100.
May 11, 1889, De Pere News, Lower Fox River, 100, over 100.
June 1, 1889, De Pere News, Lake Winnebago, 120.
May 17, 1890, Holland City News, Grand Haven, 178 (46 pounds of eggs).
May 31, 1890, De Pere News, Lower Fox River, over 160.
May 27, 1894, Menominee Herald, Menominee River, 120 (81 inches)
May 19, 1894, County Herald (Sheboygan), Sturgeon Bay, 148.
June 9, 1894, De Pere News, Lower Fox River, 134.
June 29, 1895, The Iron Port (Escanaba), Green Bay of Lake Michigan, 210 (8 feet, 2 inches).
May 15, 1896, Oconto County Reporter, Oconto River, 107.
May 14, 1897, Oconto County Reporter, Oconto River, 120.
May 15, 1897, Peshtigo Times, Menominee River, 175.
May 29, 1897, Holland City News, Grand Haven--130.
June 26, 1897, County Herald, Sheboygan, 140.
May 18, 1898, De Pere News, Lower Fox River, 115.
May 20, 1898, Holland City News, Grand Haven--200 pounds (almost 7 feet long).
June 1, 1898, De Pere News, Lower Fox River, 104, 140.
June 3, 1898, Manistique Pioneer-Tribune, Thompson, 314 (11 feet, 10 inches).
June 11, 1898, County Herald, Sheboygan, 100, 150.
May 4, 1899, Muskegon Weekly Chronicle, Muskegon River, at least 150.
May 13, 1899, Port Washington Star, Lake Winnebago, over 100.
May 27, 1899, Allegan Gazette, Kalamazoo River, 120, 119.
June 3, 1899, Port Washington Star, Port Washington, 100.
April 28, 1900, Port Washington Star, Upper Fox River, 124.
June 23, 1900, Port Washington Star, Port Washington, 117.
May 17, 1902, St. Joseph Saturday Herald, Green Bay near Menominee, 128.
May 21, 1902, Peshtigo Times, Mud Bay, Door County, 412.
June 4, 1903 -Manitowoc Citizen, Manitowoc, 137.
June 26, 1903, Kewaunee Enterprise, Upper Fox River, 209 (9 feet, 3 inches).
May 4, 1904, De Pere News, Lower Fox River, 125.
September 7, 1904, De Pere News, Lower Fox River, 170.
May 6, 1905, St. Joseph Saturday Herald, Kalamazoo River, 138.
June 13, 1907, Manitowoc Citizen, Manitowoc, 127 (6 feet).
May 16, 1908, Daily Herald-Leader, Menominee, Menominee River, 125.
June 3, 1912, De Pere News, Lower Fox River, 125 (8 feet).
June 26, 1912, De Fere News, Ellison Bay, 178.
August 13, 1913, De Pere News, Lake Winnebago, 187.5 (6 feet).
July 22, 1914, De Pere News, Lake Winnebago, 176 (6 feet, 8 inches).
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