Resources related to Times of Migration

Implications of Demographic Uncertainty for Harvest Management of North American Sea Ducks

In 2010, the Sea Duck Joint Venture (SDJV) identified the need for improved science support for harvest and habitat management of North American sea ducks.
In order to prioritize monitoring and research needs in support of harvest management, we applied a Prescribed Take Level (PTL) framework to assess the influence of uncertainty about sea duck demographic
parameters on comparisons of observed and allowable harvest estimates. We focused on 7 populations of North American sea ducks: the American subspecies of common eider (Somateria mollissima dresseri

Implications of Demographic Uncertainty for Harvest Management of North American Sea Ducks

Site fidelity and the demographic implications of winter movements by a Migratory Bird the Harlequin Duck (Histrionicus)

Understanding the degree of demographic connectivity among population segments is
increasingly recognized as central to the fields of population ecology and conservation
biology. However, delineating discrete population units has proven challenging,
particularly for migratory birds as they move through their annual cycle. In this
study, radio telemetry was used to assess movement rates among habitats by harlequin
ducks Histrionicus histrionicus during the non-breeding season in Prince William

Site fidelity and the demographic implications of winter movements by a Migratory Bird the Harlequin Duck (Histrionicus)

Fitting statistical distributions to seaduck count data: Implications for survey design and abundance estimation

Determining appropriate statistical distributions for modeling
animal count data is important for accurate estimation of abun-
dance, distribution, and trends. In the case of sea ducks along the
U.S. Atlantic coast, managers want to estimate local and regional
abundance to detect and track population declines, to define
areas of high and low use, and to predict the impact of future
habitat change on populations. In this paper, we used a modified
marked point process to model survey data that recorded flock

Fitting statistical distributions to seaduck count data: Implications for survey design and abundance estimation

Sea Duck Joint Venture Implementation Plan 201 5 - 201 7

PRIORITIES 2015–2017 Priorities set out in this Implementation Plan are designed to help meet the SDJV mission,
which is to “...promote the conservation of all North American sea ducks through partnerships by providing greater
knowledge and understanding for effective management.”
The 2014-2018strategic plan reflects a significant shift in focus for the SDJV, from a broad-based science program
to a more focused program intended to provide information most needed by managers to make informed

Sea Duck Joint Venture Implementation Plan 2015 - 2017

Food Habits of Sea Ducks Atlantic Maritimes

Numbers of scoters (black, surf, and white-winged) and long-tailed ducks wintering in the Maritime provinces of Canada and the Chesapeake Bay (MD and VA, USA) have noticeably declined in recent years. Common goldeneye populations have also declined. Changes in the location of these seaduck populations have also been observed and have given managers new concerns. Many factors related to human population increases have been implicated in causing changes in the distribution and abundance of seaducks.

Food Habits of Sea Ducks

Sea Duck Joint Venture Strategic Communications Plan 2015-2019

The mission of the Sea Duck Joint Venture(SDJV)is to promote the conservation of North American sea ducks through partnerships by providing greater knowledge
and understanding for effective management. SDJV focuses on the 15 species of North American sea ducks on their coastal water habitat for migration and wintering as well as boreal forest and tundra habitat for nesting. Since the JV’s founding in 1998, the four pillars of its work have included science, communications, funding, and conservation.

Sea Duck Joint Venture Strategic Communications Plan 2015-2019

Searching for the cause of sea ducks’ dire health

Thousands of Common Eider carcasses have been found floating in the cold water off Cape Cod or rotting on beaches. Many more of the birds have been found emaciated, exhausted, and suffering, often near death. In recent years, a mysterious virus has taken a mounting toll on the region’s common eiders, a normally bulky sea duck considered a barometer for the health of Cape Cod Bay.

Searching for the cause of sea ducks’ dire health

Fitting statistical distributions to seaduck count data: Implications for survey design and abundance estimation

Determining appropriate statistical distributions for modeling animal count data is important for accurate estimation of abundance,distribution,and trends.In the case of
seaducks along the U.S.Atlantic coast,managers want to estimate local and regional abundance to detect and track population declines, to define

Fittingstatisticaldistributionstoseaduckcountdata: Implicationsforsurveydesignandabundanceestimation

A group movement model for waterfowl aggregation

Abstract
This paper presents a simple stochastic model of the dynamics of waterfowl aggregation, investigates model fit, and considers
variance in the model’s parameter estimators. The model, a marked-point process with four parameters, describes a behavioral
process defined by the movements of animal groups. My approach provides new methods to explore animal social behavior. I
illustrate the fit of the model to field observations of 39 aggregations observed when they were not at equilibrium and outline a

A group movement model for waterfowl aggregation

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