Black Scoter (<i>Melanitta americana</i>) Winter Habitat Use and Movement Patterns Along the Atlantic Coast of the United States

While the Atlantic coast of the United States and Canada is a major wintering area for sea ducks, habitat use and movement patterns of sea ducks, such as the black scoter (Melanitta americana), are vastly unknown and understudied. The lack of information in conjunction with a rise in human activity in and near the Atlantic Ocean has led to an increased effort for the conservation and management of sea ducks, while minimizing human conflicts. The objectives of my study were to 1) identify variables that had the most influence on black scoter distribution in the Atlantic Ocean along the southeastern coast of the United States and 2) investigate the winter movement patterns of black scoters in the Atlantic Ocean by quantifying the number of wintering sites, arrival and departure dates to and from the wintering grounds, days at a wintering site, area of a wintering site, distance between wintering site, and test if winter movement patterns varied by sex or geography. To identify the variables that were the most influential on black scoter distribution along the southeastern coast of the United States, I used aerial survey data from 2009 to 2012 provided by the United States Fish and Wildlife Service. I ran a Least Absolute Shrinkage and Selection Operator (LASSO) with broad and fine scale oceanographic and weather variables. The oceanographic variables of bathymetry, ocean floor slope, and distance to shore were found to have the greatest association with the distribution of black scoter. Additionally, my results suggest that oceanographic variables have a stronger relationship with black scoter distribution than weather variables. To quantify winter movement patterns of black scoters, I used satellite telemetry data from 2009 to 2012 that was provided by the Sea Duck Joint Venture. I used Mann-Whitney U-tests to quantify the differentiation between sex and geography. While there was no difference between sexes, average wintering site area and distance between wintering sites differed by geographic region. Southern wintering sites were larger and farther apart than northern wintering sites. These results suggest that black scoter habitat use and movement patterns vary regionally. My results enable managers to focus sampling effort for black scoter abundance and distribution along the Atlantic coast. Habitat characteristics for black scoters identified in my study area should be carefully considered when planning anthropogenic activities along the southeast coast of the United States, such as offshore energy development.

Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.