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USGS2016

Captive propagation, reproductive biology, and early life history of Etheostoma wapiti (Boulder Darter), E. vulneratum (Wounded Darter), and E. maculatum (Spotted Darter)

Reproductive biology and early life-history data are important for understanding the ecology of fishes. In 2008, we conducted captive propagation studies on 3 species of darters of the subgenus Nothonotus : Etheostoma wapiti (Boulder Darter), E. vulneratum (Wounded Darter), and E. maculatum (Spotted Darter). The length of spawning period and associated range of water temperatures for the Wounded Darter exceeded that of the Spotted Darter and Boulder Darter. The mean number of eggs produced per female was lowest for Boulder Darter and highest in the Wounded Darter. The Boulder Darter had the highest percent of eggs hatched, the lowest percent larval to juvenile stage survivorship, and the lowest mean number of juveniles produced per female. Egg diameters at deposition and prior to hatch were smallest for the Spotted Darter. If reproductive biology and early lifehistory information from captive fishes represent that of wild populations, then the data obtained during this study are relevant to development and implementation of conservation and management plans for these closely related darter species.

North Carolina, Tennessee, West Virginia↗

USGS2014

Captive propagation, reproductive biology, and early life history of the Diamond Darter ( Crystallaria cincotta )

Reproductive biology and early life history data are critical for the conservation and management of rare fishes. During 2008–2012 a captive propagation study was conducted on the Diamond Darter, Crystallaria cincotta , a rare species with a single extant population in the lower Elk River, West Virginia. Water temperatures during spawning ranged from 11.1–23.3 C. Females and males spawned with quick vibrations, burying eggs in fine sand in relatively swift clean depositional areas. Egg size was 1.8–1.9 mm, and embryos developed within 7 to 11 d. Diamond Darters were 6.7–7.2 mm total length (TL) at hatch. Larvae ranged from 9.0–11.0 mm TL following a 5–10 d period of yolk sac absorption. Larvae had relatively large mouth gapes and teeth and were provided brine shrimp Artemia sp., Ceriodaphnia dubia neonates, marine Brachionus rotifers, and powdered foods (50–400 µm) but did not appear to feed in captivity, except for one observation of larval cannibalization. Larvae survived for a maximum of 10 d. To increase larval survival and reduce the possibility of cannibalism, other alternative food sources are needed during captive propagation.

Tennessee↗

USGS1999

Reproductive biology and juvenile recruitment of the shinyrayed pocketbook, Lampsilis subangulata (Bivalvia: Unionidae) in the Gulf Coastal Plain

The reproductive biology, glochidial morphology and recruitment of the federally endangered shinyrayed pocketbook, Lampsilis subangulata , were studied from May 1995 to July 1996 in the Flint River system, Georgia. Gravid female L. subangulata were found nine months of the year. On 19 May 1995, a L. subangulata was discovered releasing a superconglutinate, the first record confirming that this species used this specialized reproductive strategy. Superconglutinate release occurred from late May to mid-July in water temperatures ranging from 20.0 to 23.5 C. Laboratory experiments indicated that two fish species served as primary hosts, the spotted bass ( Micropterus punctulatus ) and largemouth bass ( M. salmoides ). Secondary host fish included the eastern mosquitofish ( Gambusia holbrooki ), guppy ( Poecilia reticulata ) and bluegill ( Lepomis macrochirus ). The glochidial morphology of L. subangulata was similar to other lampsiline species. Using quantitative survey methods, no evidence of recent juvenile recruitment was found in the largest known extant L. subangulata population.

Georgia↗

USGS2002

Reproductive biology of four freshwater mussels (Bivalvia: Unionidae) endemic to eastern Gulf Coastal Plain drainages of Alabama, Florida, and Georgia

The reproductive biology and glochidial shell morphology of three federally endangered freshwater mussels, the fat threeridge, Amblema neislerii; Gulf moccasinshell, Medionidus penicillatus; and oval pigtoe, Pleurobema pyriforme; and one federally threatened mussel, the purple bankclimber, Elliptoideus sloatianus, were studied from May 1995 to June 1997 in the Apalachicola, Flint, and Ochlockonee river drainages of Florida and Georgia. Gravid A. neislerii were found in early June. Laboratory experiments indicated that five fish species served as hosts: weed shiner, Notropis texanus; bluegill, Lepomis macrochirus; redear sunfish, L. microlophus; largemouth bass, Micropterus salmoides; and blackbanded darter, Percina nigrofasciata. Elliptoideus sloatianus were found gravid from late February through mid-April. None of the 14 fish species exposed to E. sloatianus glochidia resulted in the identification of a primary host fish. Medionidus penicillatus were found gravid during September, November, March, and April. The brown darter, Etheostoma edwini, and blackbanded darter, Percina nigrofasciata, were identified as primary host fishes for M. penicillatus. Pleurobema pyriforme were found gravid from March through July. Only the sailfin shiner, Pleronotropis hypsehpterus, was identified as a primary host fish for P. pyriforme. Glochidial shell morphology of A. neislerii, M. penicillatus, and P. pyriforme were similar to other species in their respective genera. The glochidia of the monotypic species E. sloatianus were morphologically most similar to Epioblasma brevidens and E. capsaeformis.

American Malacological Bulletin↗

USGS2007

Reproductive biology of the brown tree snake, Boiga irregularis (Reptilia: Colubridae), during colonization of Guam and comparison with that in their native range

Since their introduction to Guam shortly after World War II, brown tree snakes, Boiga irregularis (Merrem), have seriously impacted the biota and human population of the island. Understanding the biology of this exotic species will likely be important to the success of control programs. We compared the reproductive biology of 782 B. irregularis caught on Guam during the 1980s with results from published studies of native-range populations. Average and maximum sizes of mature snakes on Guam were larger than those from Australian populations. The majority of female brown tree snakes matured at snoutvent lengths (SVLs) of 910-1,025 mm, and most males matured at SVLs of 940-1,030 mm. on Guam. Based on growth rates from the early 1990s on Guam, sexual maturity is estimated to occur during a snake's third or fourth year. Only one female (0.3%) in our data set had oviductal eggs. Clutch size was estimated at 4.3 (SD = 2.2), based on large vitellogenic ovarian follicle (???30 mm in length) and oviductal egg counts. Unlike their Australian counterparts, the Guam population reproduced year-round. Our data offer insights into the likely reproductive patterns of brown tree snakes should they infest other islands in the Pacific region. ?? 2007 by University of Hawai'i Press. All rights reserved.

Pacific Science↗

USGS2025

Reproductive biology of invasive grass carp (Ctenopharyngodon idella) in two North American systems

Grass carp ( Ctenopharyngodon idella ) are nonnative, herbivorous freshwater fish that represent an ecological threat in North American waters. However, data are limited on reproductive biology specific to wild populations in midwestern North America, despite recent concern for grass carp establishment within the Great Lakes. Basic information on reproductive traits could be useful to determine reproductive potential, inform future population modelling and provide information to aid control efforts. Our objectives were to evaluate grass carp age-at-maturity, spawning season timing, fecundity type, developmental timing and spawning strategy. Additionally, we evaluated the reliability of the gonadosomatic index (GSI) as a proxy for identifying mature grass carp and compared body condition across study areas. We sampled grass carp in portions of the Mississippi River watershed within the state of Missouri and within the Lake Erie basin. Based on gonad histological samples ( n = 274), grass carp are batch spawners with indeterminate fecundity and asynchronous ovarian developmental timing. This allows flexibility in their spawning, exemplified by a protracted spawning season in Lake Erie (April to November) in temperatures ranging from 12.3 to 27.3°C. Minimum observed age-at-maturity for females in Missouri and for both males and females in the Lake Erie population was age-3 and age-2 for males in Missouri. Accuracy of GSI as a measure of maturity during the spawning season was 89.7% and 87.5%, for females and males, respectively. Compared to Missouri, grass carp in Lake Erie had a significantly higher body condition, and females ready to spawn had significantly higher GSI values, suggesting that the grass carp in Lake Erie are healthier and more fecund relative to Missouri and, if left uncontrolled, potentially have a high probability of establishment within the Great Lakes. The results of this study will allow managers to identify the reproductive status of grass carp in the field and more accurately estimate populations and reproductive potential.

Michigan, Missouri, Ohio↗

USGS2022

Lake Superior Kiyi reproductive biology

Objective The Lake Superior Kiyi Coregonus kiyi is an understudied species being considered for reintroduction into Laurentian Great Lakes where it no longer occurs. Herein, we provide descriptions of Kiyi reproductive biology with the intention of guiding potential gamete collections for propagation. Methods Data were collected on Kiyi spawning timing, spawning locations, spawning season catch rates, length at sexual maturity, sex ratios, fecundity, egg size, and larval occurrences in Lake Superior from 1996–2021. These data were compared to observations made a century prior in Lakes Michigan, Ontario, and Superior. Result Contemporary Kiyi spawning occurred between late December and late January when surface water temperatures cooled to <4°C. Spawning Kiyi were caught almost exclusively in 38.1-mm stretch mesh, as compared to larger meshes (50.8–76.2 mm). Capture depths for developing, ripe, running, and spent female Kiyi were similar and ranged from 82 to 221 m. Fifty percent of female and male Kiyi were classified as sexually mature at ~150 mm total length. Fecundity estimates ranged from 1,578 to 6,720 eggs/female. Mean diameter of unfertilized eggs was 1.7 mm. Recently hatched larval Kiyi were collected at the surface during May–July at 62 of the 113 locations sampled throughout the lake in 2019. Conclusion Our work suggests that Kiyi gamete collection efforts from mid-December through January using 38.1-mm gill-net panels set at bathymetric depths of at least 100 m would maximize the collection of spawning Kiyi and reduce the bycatch of other Coregonus species. Future research questions include the following: (1) “Do Kiyi form spawning aggregations at specific spawning areas, or do they spawn indiscriminately across the lake?”; (2) “Do Kiyi spawn near the bottom or up in the water column?”; (3) “What is the relationship between fall lake overturn and Kiyi spawn timing?”; and (4) “Could summer larval and age-0 Kiyi collections provide an opportunity for establishing a captive broodstock?”

Lake Superior↗

USGS2026

Plasticity in the reproductive biology of Yellowstone cutthroat trout Oncorhynchus virginalis bouvieri in Yellowstone Lake following lake trout Salvelinus namaycush invasion

Yellowstone cutthroat trout Oncorhynchus virginalis bouvieri in Yellowstone Lake are the focus of intensive conservation efforts due to the threat of predation by invasive lake trout Salvelinus namaycush . Suppression gillnetting has reduced the abundance of predatory lake trout, and the Yellowstone cutthroat trout population is recovering. Long-term monitoring indicates the size structure of the population shifted following lake trout invasion, suggesting that reproductive demographic rates of Yellowstone cutthroat trout may have changed. Length at 50% probability of maturity, as assessed using histological analysis of gonadal tissue, was 479 mm (95% confidence interval [CI] 467–490 mm) for females and 406 mm (95% CI 386–430 mm) for males, compared to 330 mm for males and females historically. Currently, age at 50% probability of maturity is 6.6 for females and 5.4 for males. The rate of skipped spawning was 3% for females and 38% for males. Mean absolute fecundity was 2897 ovarian follicles/individual at present compared to 1141 ovarian follicles/individual before lake trout invasion. Mean relative fecundity was 2157 ovarian follicles/kg. This research illustrates the plasticity in the reproductive strategies of fishes as a result of an invasive species. Understanding the reproductive biology of fish populations is vital for effective fisheries management, and these results are integral to a population model that can be used to develop new conservation benchmarks for Yellowstone cutthroat trout.

Wyoming↗

USGS2012

Age, growth, and reproductive biology of three catostomids from the Apalachicola River, Florida

Riverine catostomids can show a wide range of interspecific variation in life-history characteristics. Understanding these differences is an important consideration in evaluating the sensitivity of these fishes to disturbance and in formulating effective conservation strategies, particularly when dealing with an assemblage consisting of multiple species within a watershed. We collected Apalachicola redhorse Moxostoma n. sp. cf. poecilurum ( n = 125), spotted sucker Minytrema melanops ( n = 94), and quillback Carpiodes cyprinus ( n = 94) to determine age, growth, and reproductive biology of spawning catostomids in the Apalachicola River, Florida, during 2007. Quillback was the smallest in total length at age; longest-lived; most fecund; and produced the smallest eggs. Apalachicola redhorse was the largest in body size; had an intermediate life span; and produced the fewest yet largest eggs. Spotted sucker was more similar to Apalachicola redhorse in most characteristics. Growth during ages 1-3 in all three species seemed to be negatively related to the proportion of observations of extreme flow, both high (Q 90 ) and low (Q 10 ), per year and a positive response in growth rate to high flows (>Q 75 but < Q 90 ). However, Apalachicola redhorse and spotted sucker growth was more sensitive to flow conditions than that of quillback. Our results suggest the life histories and ecological response of Apalachicola River catostomids to flow regulation are important components for developing strategies that incorporate the needs of these fishery resources into an ecosystem-based management approach.

Florida↗

USGS2024

Age, growth, and reproductive biology of Achilles tang (Acanthurus achilles) around Hawai'i Island, USA

A culturally important food fish in Hawai'i, Achilles tang ( Acanthurus achilles Shaw), recently experienced sharp declines in biomass, density, and average length in west Hawai'i Island. In December 2022, State resource managers placed a 2-year moratorium on the Achilles tang fishery in west Hawai'i Island so that the cause of the collapse could be explored. The lack of life-history information for Achilles tang from Hawai'i, or elsewhere in its range, has been noted as an impediment to decision-making. Therefore, our objectives were to characterize this population’s age, growth, and reproductive biology. In working with community fishers, we collected 363 individuals ranging 69 – 264 mm in fork length (FL) and 0 – 39 years in age based on estimates from otoliths. Achilles tang in Hawai'i exhibit a high growth rate, reaching 138 ± 11 mm FL (mean ± SE) in their first year, and exhibit relatively little growth after their second year (< 5 mm yr −1 ). The majority of males (92.0% of n = 101) and females (73.6% of n = 159) were classified as spawning capable or actively spawning, without annual or lunar periodicity. Our study highlights that the basic biology of Achilles tang poses unique challenges to fisheries managers looking to ensure its sustainable harvest. Future research will aim to characterize the susceptibility of recruits’ habitat to local environmental stressors and the relative connectivity of juvenile and adult habitats.

Hawaii↗

USGS2015

Reproductive biology of Ambystoma salamanders in the southeastern United States

Reproductive aspects of Ambystoma salamanders were investigated at sites in Louisiana (2010–12) and Mississippi (2013). Three species occurred at the Louisiana site, Spotted Salamander ( A. maculatum ), Marbled Salamander ( A. opacum ), and Mole Salamander ( A. talpoideum ), whereas only Spotted Salamanders were studied at the Mississippi site. A total of 162 and 71 egg masses of Spotted Salamanders were examined at the Louisiana and Mississippi sites, respectively. Significantly more Spotted Salamander eggs per egg mass were observed at the Mississippi site (x̄ = 78.2) than the Louisiana site (x̄ = 53.8; P < 0.001). The mean snout–vent length of female Spotted Salamanders at the Mississippi site (82.9 mm) was significantly larger than the Louisiana site (76.1 mm; P < 0.001). Opaque Spotted Salamander egg masses were not found at the Mississippi site, but accounted for 11% of examined egg masses at the Louisiana site. The mean number of eggs per egg mass at the Louisiana site did not differ between opaque (47.3) and clear (54.6) egg masses (P = 0.21). A total of 47 egg masses of the Mole Salamander were examined, with a mean number of 6.7 embryos per mass. Twenty-three individual nests of the Marbled Salamander were found either under or in decaying logs in the dry pond basins. There was no difference between the mean numbers of eggs per mass of attended nests (93.0) versus those that were discovered unattended (86.6; P = 0.67). Females tended to place their nests at intermediate heights within the pond basin.

Louisiana, Mississippi↗

USGS2014

Comparative reproductive biology of sympatric species: Nest and chick survival of American avocets and black-necked stilts

Identifying differences in reproductive success rates of closely related and sympatrically breeding species can be useful for understanding limitations to population growth. We simultaneously examined the reproductive ecology of American avocets Recurvirostra americana and black-necked stilts Himantopus mexicanus using 1274 monitored nests and 240 radio-marked chicks in San Francisco Bay, California. Although there were 1.8 times more avocet nests than stilt nests, stilts nonetheless fledged 3.3 times more chicks. Greater production by stilts than avocets was the result of greater chick survival from hatching to fledging (avocet: 6%; stilt: 40%), and not because of differences in clutch size (avocet: 3.84; stilt: 3.77), nest survival (avocet: 44%; stilt: 35%), or egg hatching success (avocet: 90%; stilt: 92%). We reviewed the literature and confirmed that nest survival and hatching success are generally similar when avocets and stilts breed sympatrically. In addition to species, chick survival was strongly influenced by age, site, and year. In particular, daily survival rates increased rapidly with chick age, with 70% of mortalities occurring ≤ 1 week after hatch. California gulls Larus californicus caused 55% of avocet, but only 15% of stilt, chick deaths. Differential use of micro-habitats likely reduced stilt chick’s vulnerability to gull predation, particularly during the first week after hatch, because stilts nested in vegetation 2.7 times more often than avocets and vegetation height was 65% taller at stilt nests compared with avocet nests. Our results demonstrate that two co-occurring and closely related species with similar life history strategies can differ markedly in reproductive success, and simultaneous studies of such species can identify differences that limit productivity.

California↗

USGS2019

Reproductive biology of Grey-breasted Wood-Wren (Henicorhina leucophrys): A comparative study of tropical and temperate wrens

We provide a detailed breeding biology account for the Grey-breasted Wood-Wren ( Henicorhina leucophrys ) and a comparison of the reproductive life history of tropical and temperate wrens using literature data. We conducted this study at Yacambú National Park in Venezuela from 2002 to 2008. Clutch size was 1.99 (SE 0.01) and fresh egg mass was 2.35 g (0.02). Females incubated the eggs for 19.74 d (0.37), and nestlings left nests at 17.37 d (0.18). Nest attentiveness (percent time spent on the nest) increased across the incubation period while brooding attentiveness decreased as nestlings aged. Brooding effort began with similar attentiveness as at the end of incubation. Food provisioning rate and feeding rate per nestling increased as nestlings aged. Growth rates ( K ) based on mass, tarsus, and wing chord were relatively slow at 0.375, 0.246, and 0.257, respectively. The nesting season extended from mid-March to late June for 7 years and the average nesting season length was 64.5 d (3.68) with a median of May 4. Nest success was 22%. Nest predation was the cause of 77% of nest failures with a total daily predation rate of 0.030 (0.002). Results obtained from the literature demonstrated that tropical wrens averaged smaller clutch sizes and longer incubation periods than relatives in the temperate region.

Yacambú National Park↗

USGS2022

Pedigree analysis and estimates of effective breeding size characterize sea lamprey reproductive biology

The sea lamprey ( Petromyzon marinus ) is an invasive species in the Great Lakes and the focus of a large control and assessment program. Current assessment methods provide information on the census size of spawning adult sea lamprey in a small number of streams, but information characterizing reproductive success of spawning adults is rarely available. We used RAD-capture sequencing to genotype single nucleotide polymorphism (SNP) loci for ~1600 sea lamprey larvae collected from three streams in northern Michigan (Black Mallard, Pigeon, and Ocqueoc Rivers). Larval genotypes were used to reconstruct family pedigrees, which were combined with Gaussian mixture analyses to identify larval age classes for estimation of spawning population size. Two complementary estimates of effective breeding size ( N b ), as well as the extrapolated minimum number of spawners ( N s ), were also generated for each cohort. Reconstructed pedigrees highlighted inaccuracies of cohort assignments from traditionally used mixture analyses. However, combining genotype-based pedigree information with length-at-age assignment of cohort membership greatly improved cohort identification accuracy. Population estimates across all three streams sampled in this study indicate a small number of successfully spawning adults when barriers were in operation, implying that barriers limited adult spawning numbers but were not completely effective at blocking access to spawning habitats. Thus, the large numbers of larvae present in sampled systems were a poor indicator of spawning adult abundance. Overall, pedigree-based N b and N s estimates provide a promising and rapid assessment tool for sea lamprey and other species.

Michigan↗

USGS2007

Comparison of diet, reproductive biology, and growth of the pig frog (Rana grylio) from harvested and protected areas of the Florida Everglades

Distinct differences in body size exist among three Rana grylio populations in areas of the Florida Everglades that differ in frog harvest pressure and hydroperiod. Frogs from two populations are harvested regularly throughout the year, while those in the third are protected from harvest. We compared seasonal and sex differences in diet, reproduction, and growth across these populations to examine life-history patterns. By volume, crayfish and anurans were the most abundant prey items for all adults across sites. Frogs from drier sites consumed more crayfish than frogs from the wettest site. Anurans were abundant in the diet during the wet season, while crayfish and fish were abundant during the dry season. More frogs with empty stomachs were captured during the wet season than the dry season. Feeding, growth, and fat deposition were greatest during the dry season across all sites. Although females were found in all reproductive stages throughout the year, the highest percentage of females had mature ova during the late dry season and spent ovaries during the early wet season. Individual patterns of growth were similar across all sites and matched historical growth data from the 1950s. Differences in body size among sites were most likely attributable to differential mortality (i.e., harvest pressure, predation) rather than to differences in food access or growth. ?? 2007 by the American Society of Ichthyologists and Herpetologists.

Copeia↗

USGS1975

Reproductive biology of the band-tailed pigeon in Colorado and New Mexico

Band-tailed pigeons ( Columba fasciata ) occur in two major populations in western North America, a coastal population ( C. f. monilis ) and an interior population ( C. f. fasciata ) (A.O.U. 1957). The interior population inhabits portions of Colorado, New Mexico, Arizona, Utah, Texas, and the highlands of Mexico. This pigeon is one of several species of birds in western North America that show unseasonal and variable nesting periods (see Ligon 1971). Active nests have been found in some portion of the species' range in every month of the year (Swarth 1900, Thayer 1909, Stephens 1913, Lamb 1926, Abbott 1927, Vorhies 1928, Neff 1947, MacGregor and Smith 1955). Although several studies of the breeding biology of the Band-tailed Pigeon have been made on the Pacific coast population (Glover 1953, MacGregor and Smith 1955, Houston 1963, March and Sadleir 1970, Zeigler 1971) few studies have been done of the interior population (Fitzhugh 1970). The breeding cycle of the interior population is poorly understood, although many observations of individual nests have been reported (Neff 1947, Fitzhugh 1970). The purpose of this study was to document the gonadal cycles of free-living Band-tailed Pigeons in Colorado and New Mexico and to study the species' photoperiod responses. From this information we have attempted to explain the normal breeding cycle of the pigeon and to explain its occasional unseasonal breeding.

The Auk↗

USGS1997

Reproductive biology of the green turtle (Chelonia mydas) at Tern Island, French Frigate Shoals, Hawai`i

We monitored nesting of the green turtle (Chelonia mydas Linnaeus) on Tern Island, French Frigate Shoals, in the Northwestern Hawaiian Islands from 1986 through 1991. Egg oviposition occurred between 26 April and 20 October. Nesting peaked between mid-June and early August. Hatchlings emerged between mid-August and early October. Mean incubation period was 66.0 (range 53-97) days. Mean clutch size was 92.4 (range 33-150) eggs. Mean hatching success was 78.6% when averaged over success of individual nests and 81.1% when calculated as percentage of total number of eggs. Natural hatchling emergence was 71.1%, based on percentage of total number of eggs. Live and dead hatchlings were found when nests were excavated and accounted for 10.0% of the eggs. Incubation periods tended to be longer in early and later portions of the season than in midseason, and incubation periods tended to decrease the farther inland the nest was situated from the high tide line. Maximum hatching success occurred at an incubation length of 66.7 days. Other trends indicated that nesting peaked near 5 July when conditions produced a near optimal incubation period for yielding maximum hatching success.

Pacific Science↗

USGS2000

Survival and reproductive biology of the Bachman's Sparrow

We estimated breeding season survival rates and nest success for Bachman's Sparrows at the Savannah River Site, South Carolina, using radio telemetry. The 1995 breeding season (2 May-9 Aug) survival rate was 0.905 (95% C. I. 0.779-1.03) with 2 mortalities out of 20 individuals. The 1996 breeding season (10 May-25 Jul) survival rate was 0.882 (95% C. I. 0.729-1.04) with 2 mortalities out of 18 individuals. No significant differences in survival rates were detected between years, sexes, or habitat types. The overall breeding season survival rate was 0.893 (95%, C. I. 0.794-0.992). Daily nest survival rate in 1995 was 0.952 (0.013 SE N=26) and 0.889 (0.027 SE N=15) in 1996. Daily nest survival was significantly greater during 1995, with only 1 of 15 nests fledging a single individual in 1996. Nests attempts initiated before 15 June (0.975 [0.012], N=15) had higher survival rates than later nest attempts (0.914 [0.029] N=11, C2=3.77, 1 df, P=0.05).

Proceedings of the Annual Conference of the Southe↗