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Michael D. Kaller

Publications and source records attributed to Michael D. Kaller.

7 recordsLinked to original sources
USGS2025

Invasive species in the aquarium trade: Survey of attitudes, behaviors, and knowledge among US participants

Although the aquarium trade is an important pathway for direct and indirect non-native species introductions into freshwater systems, knowledge and attitudes of participants in the trade regarding alien species issues is largely undocumented. Therefore, we administered a survey to investigate attitudes and behaviors of aquarists and non-aquarists regarding the aquarium trade as a pathway for invasive species introductions. We hypothesized aquarists would be better educated on potential introductions than non-aquarists. Due to their engagement with organisms and replication of natural habitats, we also expected aquarists would exhibit more positive attitudes and behaviors toward the environment than non-aquarists. Most respondents seemingly understood the severity of invasive species problems, regardless of status as an aquarist. Aquarists thought the aquarium trade was less responsible for species introductions than non-aquarists and also felt more aware of laws regarding invasive species. However, over half of aquarists disposed of aquarium water down a drain in their house or directly into a nearby water body, which is a known mode of invasion. This information can inform further efforts to provide educational opportunities for participants in the non-native pet/aquarium trade, with the goal of enhancing protection efforts for native biodiversity.

Alabama, Arkansas, Florida, Iowa, Louisiana, Missi↗
USGS2024

Early pandemic recreational fishing patterns across the urban-to-rural gradient in the U.S.

In 2020, the SARS-CoV-2 (COVID-19) pandemic disrupted individual and social behaviors and norms, including outdoor activities. A recreational angling survey of 18,000 licensed anglers from 10 states (AR, CT, FL, IA, MO, NC, SC, TX, UT, WY) was conducted in summer 2020 to characterize recreational fishing trends during the first few months of the pandemic. The study presented here builds off this survey by combining the survey data with county-level human population density and spring 2020 per capita COVID-19 cases to understand how anglers responded to the pandemic along the urban-to-rural continuum. Specifically, we wanted to know if population density or COVID-19 cases per capita influenced angler-reported 1) changes in license sales, 2) number of fishing trips, and 3) motivation for fishing. Overall results suggest that per capita COVID-19 cases were more influential in driving angler behavior than population density in the early pandemic (01 March 2020–31 May 2020). At the onset of the pandemic, high COVID-19 case counts were associated with an uptick in recreational angling activity. In counties with greater COVID-19 case counts, there was greater angler recruitment (i.e., attraction of new individuals to recreational fishing) and earlier license purchases. Anglers aged ≥40 years and earning ≥$50,000 living in areas of greater per capita COVID-19 cases also went on more fishing trips than they typically would. Angler motivations varied across gradients of population density and per capita COVID-19 cases: anglers living in areas of higher population densities were more likely to report fishing for stress relief, sport, and competition among friends , and anglers living in areas of higher per capita COVID-19 cases were more likely to report fishing for sport and because they had free time and less likely to report fishing for food . Management efforts can focus on retaining and reactivating pandemic anglers.

Fisheries Research↗
USGS2023

Diurnal time–activity budget and habitat use of Whooping Cranes (Grus americana) in the reintroduced Louisiana nonmigratory population

Time–activity budget studies provide valuable insights for better understanding animal behavior relative to spatial and temporal habitat use. We examined a reintroduced, nonmigratory Whooping Crane ( Grus americana ) population to determine how time–activity budgets change relative to crane age, sex, habitat type, and season. Our study area encompassed natural marshes and working wetlands primarily in southwestern Louisiana. From June 2012 to January 2016, we conducted continuous focal sampling on individuals ( n = 27) from the first 4 captive-reared cohorts released in the state. We classified age groups as juveniles, subadults, and adults, and identified 5 main habitat types utilized by cranes in Louisiana: crawfish ponds, rice fields, agricultural levees/farm roads, fallow fields, and natural wetlands. On average, cranes spent approximately 53% of their diurnal time–activity budget foraging. Maintenance/rest (28%), vigilance (12%), locomotion (6%), and other/unknown (2%) behaviors accounted for the remainder of the time observed. Foraging most frequently occurred in fallow fields and crawfish ponds where cranes likely encountered greater invertebrate biomass and density. Cranes tended to spend less time foraging and more time on maintenance as they aged, which could indicate age-dependent differences based on experience on the landscape. Vigilance levels were not significantly affected by age, but males tended to be more vigilant than females. As this young population continues to mature, additional study of breeding pairs and family groups may elucidate other behavioral differences in response to the dynamic habitat conditions in the region.

The Wilson Journal of Ornithology↗
USGS2022

Hydrologic connectivity and residence time affect the sediment trapping efficiency and dissolved oxygen concentrations of the Atchafalaya River Basin

Little is known about water movement, volume, or residence time (RT), and how those characteristics affect sediment trapping efficiency (TE) and dissolved oxygen concentrations (DO) in the United States' largest remaining bottomland hardwood swamp, the Atchafalaya River Basin. To better understand these dynamics, this study used bathymetry, lidar, and stage records to determine volumes in the Basin's hydrologically distinct water management units (WMUs). Discharge measurements determined flow distribution and RT. Residence time was compared with DO to identify conditions that coincided with DO increases or decreases. Suspended sediment concentrations (SSC) were used to determine TE relative to calculated and measured discharge and RT. Discharge through units (85–2,200 m 3 /s) and RT (0.37–231 d) depended on connectivity and river stage. At high stages, with water temperatures >20°C, DO in the largest WMU declined by −0.21 mg/l/day. DO trends indicated less well-connected areas of the WMU contributed hypoxic waters as the flood wave lengthened and stages fell. In the two WMUs examined for TE, TE (−266% to 99% and up to 38 Gg/day) correlated with hydrologic connectivity, SSC, RT, water volume, and, in one WMU, discharge losses. Long RT and high TE indicated a high potential to process nutrients. These relationships varied among WMUs. Large volumes of sediment-laden water moving over the floodplain combined with long RT, high TE, and hypoxia indicate that this ecosystem has continental-scale importance in reducing nutrient loads to the northern Gulf of Mexico. Reports from other systems suggest similar processes may be operating on other large river floodplains globally.

Louisiana↗
USGS2010

Waterbird nest density and nest survival in rice fields of southwestern Louisiana

Rice fields in southwestern Louisiana provide breeding habitat for several waterbird species; however, little is known about nest density, nest survival and the importance of landscape context of rice fields in determining breeding activity. In 2004, 42 rice fields were searched for nests, and 40 were searched in 2005. Land uses surrounding rice fields, including irrigation canals, trees, crawfish ponds, rice, fallow and soybean fields, were examined to determine influence on nest density and survival. Nest densities were 13.5-16.0 nests/km 2 for Purple Gallinules ( Porphyrio martinica ), 3.0-13.7 nests/km 2 for Fulvous Whistling Ducks (Dendrocygna bicolor), 2.6-2.8 nests/km 2 for Common Moorhens ( Gallinula chloropus ), 0.3-0.92 nests/km 2 for Least Bitterns ( Ixobrychus exilisi ) and 0-0.6 nests/km 2 for Mottled Ducks ( Anas fulvigula ). Nest survival was 52-79% for Purple Gallinules and 39-43% for Fulvous Whistling Ducks. Apparent nest success of Common Moorhens was 73-75%, 83% for Least Bitterns and 33% for Mottled Ducks. Purple Gallinule and Common Moorhen nest densities were highest in fields with a larger proportion of irrigation canals surrounding rice fields. Purple Gallinule nest densities were greater in fields devoid of trees and landscapes dominated by rice fields and pasture, rather than landscapes containing soybean fields and residential areas. Fulvous Whistling Duck nest densities were higher in agriculturally-dominated landscapes with few trees.

Waterbirds↗
USGS2009

Foraging behavior of pileated woodpeckers in partial cut and uncut bottomland hardwood forest

In bottomland hardwood forests, partial cutting techniques are increasingly advocated and used to create habitat for priority wildlife like Louisiana black bear ( Ursus americanus luteolus ), white-tailed deer ( Odocoileus virginianus ), and Neotropical migrants. Although partial cutting may be beneficial to some species, those that use dead wood may be negatively affected since large diameter and poor quality trees (deformed, moribund, or dead) are rare, but normally targeted for removal. On the other hand, partial cutting can create dead wood if logging slash is left on-site. We studied foraging behavior of pileated woodpeckers ( Dryocopus pileatus ) in one- and two-year-old partial cuts designed to benefit priority species and in uncut forest during winter, spring, and summer of 2006 and 2007 in Louisiana. Males and females did not differ in their use of tree species, dbh class, decay class, foraging height, use of foraging tactics or substrate types; however, males foraged on larger substrates than females. In both partial cut and uncut forest, standing live trees were most frequently used (83% compared to 14% for standing dead trees and 3% for coarse woody debris); however, dead trees were selected (i.e. used out of proportion to availability). Overcup oak ( Quercus lyrata ) and bitter pecan ( Carya aquatica ) were also selected and sugarberry ( Celtis laevigata ) avoided. Pileated woodpeckers selected trees >= 50 cm dbh and avoided trees in smaller dbh classes (10-20 cm). Density of selected foraging substrates was the same in partial cut and uncut forest. Of the foraging substrates, woodpeckers spent 54% of foraging time on live branches and boles, 37% on dead branches and boles, and 9% on vines. Of the foraging tactics, the highest proportion of foraging time was spent excavating (58%), followed by pecking (14%), gleaning (14%), scaling (7%), berry-eating (4%), and probing (3%). Woodpecker use of foraging tactics and substrates, and foraging height and substrate diameter did not differ between recent partial cut and uncut forest. Partial cutting designed to improve or maintain habitat for priority wildlife did not affect pileated woodpecker foraging behavior or availability of selected trees compared to uncut forest in the short term.

Forest Ecology and Management↗