Bald Eagle Populations in the Great Lakes Region


Book Description

Heavy development in the Great Lakes area has diminished eagle nesting habitat and foraging opportunities. This document presents information on bald eagles and describes some of the challenges to bald eagle populations around the Great Lakes, including chemical contaminants in the aquatic food web. It outlines legislative protection and conservation strategies, and describes current conditions and nesting results for bald eagles.










Evaluating Great Lakes Bald Eagle Nesting Habitat with Bayesian Inference


Book Description

Bayesian inference facilitated structured interpretation of a nonreplicated, experience-based survey of potential nesting habitat for bald eagles (Haliaeetus leucocephalus) along the five Great Lakes shorelines. We developed a pattern recognition (PATREC) model of our aerial search image with six habitat attributes: (a) tree cover, (b) proximity and (c) type/amount of human disturbance, (d) potential foraging habitat/shoreline irregularity, and suitable trees for (e) perching and (f) nesting. Tree cover greater than 10 percent, human disturbance more than 0.8 km away, a ratio of total to linear shoreline distance greater than 2.0, and suitable perch and nest trees were prerequisite for good eagle habitat (having sufficient physical attributes for bald eagle nesting). The estimated probability of good habitat was high (96 percent) when all attributes were optimal, and nonexistent (0 percent) when none of the model attributes were present. Of the 117 active bald eagle nests along the Great Lakes shorelines in 1992, 82 percent were in habitat classified as good. While our PATREC model provides a method for consistent interpretation of subjective surveyor experience, it also facilitates future management of bald eagle nesting habitat along Great Lakes shorelines by providing insight into the number, type, and relative importance of key habitat attributes. This practical application of Bayesian inference demonstrates the technique's advantages for effectively incorporating available expertise, detailing model development processes, enabling exploratory simulations, and facilitating long-term ecosystem monitoring.










The Great Lakes Regional Collaboration Strategy


Book Description







Raptor Research and Management Techniques


Book Description

« Think about how we know about past events in human history (e.g., the expansion of the Roman Empire, or the American Revolution). What types of records document those events? Now think about Earth's history, specifically the past environmental or climatic conditions at times before recorded human history. What records might there be of such conditions? Make a list of your ideas. n assemblage of five major types of natural archives of Earth's environmental and climatic history. What common feature(s) do each of these paleoclimate archives share? an assemblage of 5 major types of natural records, or archives, of Earth's environmental and climatic history. Just like a diary or other historical document, the layers in these natural archives contain indirect evidence (i.e., proxies) about past conditions and events, recorded in a sequential order. The evidence is specific to a certain time period and may be general or very detailed, depending on the rate that information was recorded. The faster the rate at which the recorder grew (trees and corals), accumulated (snow and ice), or was deposited (sedimentary sequences), the more detailed the record is, and the higher its resolution. For example, a record in which an annual signal can observed has a very high resolution. In contrast, if the finest observable details are on the order of a million years, then that record would have a low resolution. »--