Resources related to Abundance

Lincoln estimates of mallard (Anas platyrhynchos) abundance in North America

Estimates of range-wide abundance, harvest, and harvest rate are fundamental for sound inferences about the role of exploitation in the dynamics of free-ranging wildlife populations, but reliability of existing survey methods for abundance estimation is rarely assessed using alternative approaches. North American mallard populations have been surveyed each spring since 1955 using internationally coordinated aerial surveys, but population size can also be estimated with Lincoln's method using banding and harvest data.

Alaska - Yukon Waterfowl breeding Population Survey 2011

ABSTRACT
Waterfowl breeding conditions within the survey area depend largely on the timing of spring
phenology. Relatively normal spring phenology occurred in Interior and Coastal Alaska in 2011.
Overall, waterfowl production is expected to be good across the survey area compared to
previous long-term (1957-2010) production.
Total duck numbers were down 28% from the previous 10-year mean, but were only down 3%
from the long-term mean (1957–2010). Dabbler ducks decreased from the previous 10-year

Trends in Duck Breeding Populations 1955-2013

This report summarizes information about the status of dabbler duck populations and wetland habitats during
spring 2013, focusing on areas encompassed by the U.S. Fish & Wildlife (USFWS) and Canadian Wildlife
Services’ (CWS)Waterfowl Breeding Population and Habitat Survey (WBPHS). This report does not include
information from surveys conducted by state or provincial agencies.
In the traditional survey area, which includes strata 1–18, 20–50, and 75–77 (Figure 1), the total duck

2013 Pacific Flyway Data Book

The following briefing material has been assembled for use by The Pacific Flyway Council, Pacific Flyway Study Committee & Cooperators and by U. S. Fish and Wildlife Service
personnel in formulating recommendations for the 2013-2014 waterfowl hunting seasons. This collection of
harvest, population, and hunter data can also serve as a desk-top reference for providing responses to inquiries
from agency personnel, the media, and public.

Population Ecology of Pacific Common Eiders on the Yukon Kuskokwim Delta, Alaska

Knowledge of ecological factors that influence birth, death, immigration, and emigration provide
insight into natural selection and population dynamics. Populations of Pacific common eiders
(Somateria mollissima v-nigrum) on the Yukon-Kuskokwim Delta (YKD) in western Alaska declined by
50-90% from 1957 to 1992 and then stabilized at reduced numbers from the early 1990’s to the
present. This study investigates the primary underlying processes affecting population dynamics of

Marine Bird Populations of Prince William Sound, Alaska,

We estimated the summer and winter abundance of marine birds in Prince William
Sound, Alaska, following the 1989 Exxon Valdez oil spill, examined changes in population size
between pre-spill and post-spill surveys, and compared pre- to post-oil spill population trends in
the oiled zone of the Sound relative to trends in the unoiled zone.
Ninety-nine species of birds were observed on surveys. Not all species were equally vulnerable to
the oil spill because of the seasonal and geographic distribution. Estimated populations of 15 to

Damage Assessment Closeout-Injury Assessment of Hydrocarbon Uptake by Sea Ducks

The goal of this project was to determine whether the Exxon Valdez oil spill had measurable sublethal effects on six species of migratory and resident seaducks in Prince William Sound and the Kodiak Archipelago. The six seaduck species were harlequin ducks, Barrow's and common goldeneyes, and surf, black, and white-winged scoters. The harlequin ducks are both resident in and winter migrants to the oil spill area. The other species do not breed in the oil spill area but are winter migrants.

Recovery Status of Barrow's Goldeneyes

Data available at the onset of this project (population trends and indices of contaminant exposure) raised concern that Barrow's goldeneye populations may have been injured by the oil spill, may not be fully recovered, and may continue to suffer deleterious effects of the spill. This project is designed to critically assess the recovery status of Barrow's goldeneye populations through assemblage and analysis of all existent, relevant data.

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