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M. S. Allen

Publications and source records attributed to M. S. Allen.

16 recordsLinked to original sources
USGS2021

The U.S. Inland Creel and Angler Survey Catalog (CreelCat): Development, applications, and opportunities

Inland recreational fishing, defined as primarily leisure-driven fishing in freshwaters, is a popular pastime in the USA. State natural resource agencies endeavor to provide high-quality and sustainable fishing opportunities for anglers. Managers often use creel and other angler survey data to inform state- and waterbody-level management efforts. Despite the broad implementation of angler surveys and their importance to fisheries management at state scales, regional and national coordination among these activities is minimal, limiting data applicability for larger-scale management practices and research. Here, we introduce the U.S. Inland Creel and Angler Survey Catalog (CreelCat), a first-of-its-kind, publicly available national database of angler survey data that establishes a baseline of national inland recreational fishing metrics. We highlight research and management applications to help support sustainable inland recreational fishing practices, consider cautions, and make recommendations for implementation.

Fisheries Magazine↗
USGS2011

Effects of variable recruitment on catch-curve analysis for crappie populations

Catch-curve analysis is frequently used to estimate total annual mortality (A) of exploited fishes, but the method assumes constant recruitment. Because populations of crappie Pomoxis spp. have exhibited large fluctuations in recruitment, I conducted simulations to assess the amount of variability in recruitment that precludes the use of a catch curve and compared results to recruitment dynamics in six crappie populations. Coefficients of variation (CV = 100.SD/mean) in recruitment to age 1 ranged from 55% to 84% among the six crappie populations. Simulations suggested that recruitment variability in these ranges would likely allow estimation of A within ± 10%, but the probability of obtaining estimates of A that were ±5% or more of the true A would exceed 0.15. 1 suggest that catch curves may be used to approximate A in crappie populations but that managers should consider the effects on management recommendations if A were ± 10% of the estimated A.

North American Journal of Fisheries Management↗
USGS2007

Effects of cryptic mortality and the hidden costs of using length limits in fishery management

Fishery collapses cause substantial economic and ecological harm, but common management actions often fail to prevent overfishing. Minimum length limits are perhaps the most common fishing regulation used in both commercial and recreational fisheries, but their conservation benefits can be influenced by discard mortality of fish caught and released below the legal length. We constructed a computer model to evaluate how discard mortality could influence the conservation utility of minimum length regulations. We evaluated policy performance across two disparate fish life-history types: short-lived high-productivity (SLHP) and long-lived low-productivity (LLLP) species. For the life-history types, fishing mortality rates and minimum length limits that we examined, length limits alone generally failed to achieve sustainability when discard mortality rate exceeded about 0.2 for SLHP species and 0.05 for LLLP species. At these levels of discard mortality, reductions in overall fishing mortality (e.g. lower fishing effort) were required to prevent recruitment overfishing if fishing mortality was high. Similarly, relatively low discard mortality rates (>0.05) rendered maximum yield unobtainable and caused a substantial shift in the shape of the yield response surfaces. An analysis of fishery efficiency showed that length limits caused the simulated fisheries to be much less efficient, potentially exposing the target species and ecosystem to increased negative effects of the fishing process. Our findings suggest that for overexploited fisheries with moderate-to-high discard mortality rates, reductions in fishing mortality will be required to meet management goals. Resource managers should carefully consider impacts of cryptic mortality sources (e.g. discard mortality) on fishery sustainability, especially in recreational fisheries where release rates are high and effort is increasing in many areas of the world. ?? 2007 Blackwell Publishing Ltd.

Fish and Fisheries↗
USGS2003

Comparison of electrofishing and rotenone for sampling largemouth bass in vegetated areas of two Florida lakes

We compared the sampling precision and efficiency of electrofishing and rotenone for assessing populations of largemouth bass Micropterus salmoides in vegetated portions of two Florida lakes. Sampling was conducted at Lochloosa and Orange lakes in north-central Florida from 1990 to 1999. Significant differences in length frequencies were determined between the two methods in 5 of 9 years for each lake. In years where differences existed, electrofishing collected larger fish than did rotenone. The maximum deviation between cumulative relative length frequencies for the two methods was not related to total vegetation, native emergent vegetation, or hydrilla Hydrilla verticallata coverage at either lake. Sampling precision was greater for electrofishing than for rotenone; electrofishing also required less sampling effort to detect changes in the abundance of juvenile and adult largemouth bass. Electrofishing was a more precise and cost-effective method than rotenone for estimating largemouth bass abundance.

North American Journal of Fisheries Management↗
USGS2003

Relation of age-0 largemouth bass abundance to hydrilla coverage and water level at Lochloosa and Orange Lakes, Florida

Changes in electrofishing catch per hour (CPH) of age-0 largemouth bass Micropterus salmoides were examined in relation to aquatic macrophytes and seasonal water elevation at Lochloosa and Orange lakes, Florida, during the 1990s. At Lochloosa Lake, stepwise multiple regression revealed a significant positive relationship between the mean CPH of age-0 largemouth bass and the percentage of areal coverage by hydrilla Hydrilla verticallata. At Orange Lake, mean CPH was directly associated with the percentage of areal coverage by hydrilla and inversely related to summer water levels. Thus, the influence of vegetation on age-0 largemouth bass abundance was similar at both lakes, but the effects of water levels were not. Further investigations into the effects of fluctuations in water levels on age-0 largemouth bass in natural lakes are needed.

North American Journal of Fisheries Management↗
USGS1987

Rock geochemistry in the Mahd adh Dhahab district, Kingdom of Saudi Arabia

Ten sets of geochemical samples from country rock, altered country rock, and quartz veins were collected to determine metal abundances and distributions in the Mahd adh Dhahab district. Gold, silver, copper, lead, and zinc are present throughout the district in veins and altered country rock. Although four generations of quartz veins are defined, there is complete gradation between types. The metals present are the same in all four, only the abundances vary. The concentrations of gold, silver, copper, lead, and zinc in altered country rock are zoned around known or projected mineralized-vein zones. Similarities in metal populations of all quartz veins, altered rock, and mineralized zones, plus the distribution of metals and some major elements, suggest that all formed as part of a single hydrothermal system. Gold in abundances greater than 1 ppm does not correlate with any other element and its distribution is very erratic. The variance in gold values between replicate samples collected in 0.5 m square panels is very high. Radio-element analyses (radium-equivalent uranium, thorium, and potassium) for 40 widely distributed sample localities indicate little variation in these elements throughout the district. If the hydrothermal system had an effect on the distribution of these elements, the system must have extended beyond the limits of the sampled area. Anomalous values of gold, silver, lead, and to a lesser extent copper and zinc in surface rock samples clearly delineated the northern mineralized zone in the upper agglomerate, and an east-vein area and west-vein area of the southern mineralized zone in the lower agglomerate. A third geochemically anomalous area occurs farther to the west in the lower agglomerate, suggesting that mineralization may have extended at least to this area along the lower agglomerate-lower tuff contact, and possibly even further to the west.

Open-File Report↗
USGS1985

Interpretation of geochemical data from panned concentrates of wadi sediments using R-mode factor analysis, Jabal Habashi Quadrangle, sheet 26F, Kingdom of Saudi Arabia

Panned-concentrate samples from wadi sediments were collected over terranes of Precambrian age intrusive, volcanic, sedimentary, and metamorphic rocks, within the Jabal Habashi quadrangle, sheet 26F, Kingdom of Saudi Arabia. Multivariate analysis of the chemical data indicates that a significant base-metal association occurs in three areas within the quadrangle. An association of strontium, barium, and calcium possibly indicates areas of hydrothermal alteration. Three other associations that were found define the major rock lithologies: niobium-yttrium-lanthanum outlines granitic terranes; magnesium-nickel indicates mafic rocks; and cobalt-vanadium-chromium have an indefinite relation with units mapped as graywacke in the central part of the quadrangle.

Open-File Report↗