Evidence of Songbird Intoxication From Rozol Application at a Black-Tailed Prairie Dog Colony

Concerns about avian poisonings from anticoagulant rodenticides have traditionally focused on secondary poisoning of raptors exposed by feeding on contaminated mammalian prey. However, ground foraging songbirds can be directly poisoned from operational applications of the anticoagulant rodenticide RozolH (0.005% chlorophacinone, active ingredient) applied as a grain bait, at black-tailed prairie dog Cynomys ludovicianus colonies. A dead western meadowlark Sturnella neglecta recovered from the study prairie dog colony displayed hemorrhaging in brain and pectoral muscle tissue, and it contained chlorophacinone residue concentrations of 0.59 and 0.49 mg/g (wet weight) in the liver and intestinal contents, respectively. Chlorophacinone residues from two Rozol-colored songbird droppings found at the study colony were 0.09 and 0.46 mg/g (wet weight). The timing of the meadowlark mortality and the occurrence of discolored droppings show that songbird exposure and poisoning can occur weeks after a Rozol application

PCBs and other toxicants in Mysis relicta

This research considers the role of Mysis relicta in the recycling of toxic organics in the Lake Michigan ecosystem. Mysids were collected at a station 20 km offshore of Grand Haven, Michigan in spring, summer, and autumn and then size-sorted. In October 1980 and May 1981, plankton samples were collected in two size categories: >78 µm and >156 µm. Mysid fecal pellets and Pontoporeia hoyi were collected in May 1981 while a fourhorn sculpin ( Myoxocephalus quadicornis ) was collected in October 1980. Concentrated extracts of all samples were analyzed for chlorinated hydrocarbons using electron capture gas chromatography. Toxic organics detected were, in order of concentration: PCB, DDE, dieldrin, γ-chlordane, and HCB. DDT, DDD, and α-chlordane were detected less frequently. PCB concentrations in mysids were similar to those observed in their plankton diet and there was no evidence of increased bioaccumulation with increased mysid age. Dieldrin and DDE generally occurred in higher concentrations in older than in younger mysids. Dieldrin concentrations were lower in the plankton than in mysids. Certain toxicants (PCBs, DDD, dieldrin, and γ-chlordane) occurred in higher concentrations in Pontoporeia hoyi than in mysids. Concentrations in the sculpin generally were intermediate to those in amphipods and mysids. Our study suggests that mysids have a significant role in the recycling of toxic organics and that the characteristic pathways vary with the contaminant.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42919/1/10750_2004_Article_BF00008114.pd

Examination of the surface microlayer of lake michigan using scanning electron microscopy

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24119/1/0000376.pd

Determination of partition coefficients and aqueous solubilities by reverse phase chromatography--I : Theory and background

Water solubilities and octanol/water partition coefficients are widely used to predict partitioning and bioconcentration phenomena for hydrophobic organic pollutants in aqueous systems. This paper is the first in a two part series describing the application of high performance reverse phase liquid chromatography (HPRPLC) for indirect estimation of these two physicochemical parameters to facilitate environmental fate and transport predictions for organic compounds. In the first part, thermodynamic factors which control partitioning processes, water solubilities, and reverse phase retention behavior are discussed, and models for interlinking these three properties are summarized. The second part presents the results of aqueous solubility and octanol/water partition coefficient predictions for a number of organic contaminants from measurements of their HPRPLC behavior, and compares the modeling capabilities of some of the theoretical partitioning/solubility equations developed in the first paper.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26005/1/0000072.pd

Analytic Detection Thresholds for Measurements of Linearly Polarized Intensity Using Rotation Measure Synthesis

A fully analytic statistical formalism does not yet exist to describe radio-wavelength measurements of linearly polarized intensity that are produced using rotation measure synthesis. In this work we extend the analytic formalism for standard linear polarization, namely that describing measurements of the quadrature sum of Stokes Q and U intensities, to the rotation measure synthesis environment. We derive the probability density function and expectation value for Faraday-space polarization measurements for both the case where true underlying polarized emission is present within unresolved Faraday components, and for the limiting case where no such emission is present. We then derive relationships to quantify the statistical significance of linear polarization measurements in terms of standard Gaussian statistics. The formalism developed in this work will be useful for setting signal-to-noise ratio detection thresholds for measurements of linear polarization, for the analysis of polarized sources potentially exhibiting multiple Faraday components, and for the development of polarization debiasing schemes.Comment: 14 pages, 6 figures, accepted for publication in MNRA

The “dirty dozen” of freshwater science: Detecting then reconciling hydrological data biases and errors

Sound water policy and management rests on sound hydrometeorological and ecological data. Conversely, unrepresentative, poorly collected or erroneously archived data introduces uncertainty regarding the magnitude, rate and direction of environmental change, in addition to undermining confidence in decision-making processes. Unfortunately, data biases and errors can enter the information flow at various stages, starting with site selection, instrumentation, sampling/ measurement procedures, post-processing and ending with archiving systems. Techniques such as visual inspection of raw data, graphical representation and comparison between sites, outlier and trend detection, and referral to metadata can all help uncover spurious data. Tell-tale signs of ambiguous and/or anomalous data are highlighted using 12 carefully chosen cases drawn mainly from hydrology (‘the dirty dozen’). These include evidence of changes in site or local conditions (due to land management, river regulation or urbanisation); modifications to instrumentation or inconsistent observer behaviour; mismatched or misrepresentative sampling in space and time; treatment of missing values, post-processing and data storage errors. As well as raising awareness of pitfalls, recommendations are provided for uncovering lapses in data quality after the information has been gathered. It is noted that error detection and attribution are more problematic for very large data sets, where observation networks are automated, or when various information sources have been combined. In these cases, more holistic indicators of data integrity are needed that reflect the overall information life-cycle and application(s) of the hydrological data

Habituated, Tolerant, or Salt-conditioned Mountain Goats and Human Safety

Interactions between humans and wildlife include a number of consumptive and non-consumptive forms. In some cases, the increased demand for wildlife viewing can precipitate new human–wildlife conflicts. Mountain goats (Oreamnos americanus; goats) are native to a number of North American mountain ranges from southeastern Alaska to southwestern Montana, USA. Goat habitat typically consists of steep terrain and cold weather habitats, which has left them particularly vulnerable to climate change. Their alpine environments also make them vulnerable to disturbance by aircraft and land-based motorized human activity. We reviewed and characterized situations in which goats in close proximity to humans on foot may become a nuisance or dangerous to people. We identify how such interactions might occur, focusing on the array of intensity observed in different settings. We summarize and evaluate interventions that have been attempted and may warrant additional research. Goats that tolerate people along hiking trails, perhaps through a habituation-like process, can typically be kept at a safe distance simply by shouting, clapping hands, or vigorous gestures. Goats that have learned to associate people with a salt reward (e.g., typically urine deposited on the ground, less frequently sweat obtained directly by licking) are more likely to be successfully hazed by tossing small stones, hitting the animal in the flank or rear. Salt-conditioned goats sometimes come within touching distance of humans; we strongly advise against prodding or poking these animals with sharp objects such as trekking poles. The recreating public that ventures into goat habitat is the ultimate source of these conflicts. Education, compliance, and possibly some infrastructure improvements can lessen the potential for conflicts and provide new and safer opportunities to view goats

The 'dirty dozen' of freshwater science: detecting then reconciling hydrological data biases and errors

Sound water policy and management rests on sound hydrometeorological and ecological data. Conversely, unrepresentative, poorly collected, or erroneously archived data introduce uncertainty regarding the magnitude, rate, and direction of environmental change, in addition to undermining confidence in decision-making processes. Unfortunately, data biases and errors can enter the information flow at various stages, starting with site selection, instrumentation, sampling/measurement procedures, postprocessing and ending with archiving systems. Techniques such as visual inspection of raw data, graphical representation, and comparison between sites, outlier, and trend detection, and referral to metadata can all help uncover spurious data. Tell-tale signs of ambiguous and/or anomalous data are highlighted using 12 carefully chosen cases drawn mainly from hydrology (‘the dirty dozen’). These include evidence of changes in site or local conditions (due to land management, river regulation, or urbanization); modifications to instrumentation or inconsistent observer behavior; mismatched or misrepresentative sampling in space and time; treatment of missing values, postprocessing and data storage errors. Also for raising awareness of pitfalls, recommendations are provided for uncovering lapses in data quality after the information has been gathered. It is noted that error detection and attribution are more problematic for very large data sets, where observation networks are automated, or when various information sources have been combined. In these cases, more holistic indicators of data integrity are needed that reflect the overall information life-cycle and application(s) of the hydrological data