Search USGSSearch

Geology topics

Mike Brown

Publications and source records attributed to Mike Brown.

3 recordsLinked to original sources

FLOwPER user guide—For collection of FLOw PERmanence field observations

The accurate mapping of streams and their streamflow conditions in terms of presence or absence of surface water is important to both understanding physical, chemical, and biological processes in streams and to managing land, water, and ecological resources. This document describes a field form, FLOwPER (FLOw PERmanence), available within a mobile application (app), for standardized data collection of the presence or absence of surface flow in streams. The FLOwPER Database is a publicly available geodataset that can be used for research and management applications. This document provides instructions on how to (1) access and download the FLOwPER field form within the mobile app service, (2) use and complete a FLOwPER field form, and (3) view and download data from the FLOwPER Database.

Open-File Report

Estimating wintering Bald Eagle densities in the Mississippi Alluvial Valley

Surveys on the winter distribution of Bald Eagles have been concentrated in the northern USA (Hastings 1988, Mattson 1988), where Bald Eagles are most common. Few density estimates for wintering Bald Eagles exist. In the past, different survey techniques with little standardization have been used. Statistical analyses and error measurements of existing winter survey data usually are not possible. The National Wildlife Federation's "midwinter Bald Eagle survey," the largest operational winter survey, is not systematic. Observers concentrate on areas where large numbers of Bald Eagles winter. We collected Bald Eagle density and distribution data in the Mississippi alluvial valley (MAV) while conducting four regional aerial surveys for Mallards ( Anas platyrhynchos ) during the winters of 1988-89 and 1989-90. Our objectives were to determine if the relatively large sample size and experimental design used in our Mallard surveys would provide accurate population estimates and additional distribution data not provided by current Bald Eagle surveys

Arkansas, Illinois, Kentucky, Louisiana, Mississip