White-fronted Geese Anser Albifrons Frontalis Research Articles

Temporal Trends in Body Condition of Arctic Geese Wintering in the Mississippi Alluvial Valley

Abstract Midcontinent populations of arctic nesting geese (hereafter, arctic geese), including greater white-fronted geese Anser albifrons frontalis, lesser snow geese Anser caerulescens caerulescens, and Ross's geese Anser rossii, have increased in abundance and shifted their winter distribution in recent decades. Consequently, the number of arctic geese wintering in the Mississippi Alluvial Valley (MAV) has increased since the 1980s. Stored endogenous nutrients are critically important to the life cycle of arctic geese as the geese use these stored nutrients to complete long-distance migration events, survive harsh winters, and supplement nutrients needed for reproduction. This study tracked temporal changes in body condition of arctic geese during the wintering period. We collected arctic geese from October–February 2015–2016 and 2016–2017 in eastern Arkansas. We used proximate analysis to determine size of lipid and protein stores as an index of body condition. Protein stores were more stable through time than lipids, but we observed a slight increase in all species as winter progressed. Mean lipid stores were dynamic and were highest in November and lowest in February. Greater white-fronted geese arrived earliest to the MAV and experienced an increase in endogenous lipid stores during early winter when high-energy food resources were most abundant. Conversely, snow and Ross's geese arrived to the MAV later and did not appear to increase their lipid stores upon arrival. All three species experienced a decline in stored lipid mass as winter progressed; a combination of factors such as resource depletion, a shift in dietary needs, physiological factors, hunting pressure, and increased energetic demands may have driven the decline. An improved understanding of the role that “nontraditional” wintering grounds exert on the nutrient dynamics of arctic geese may aid in the management of growing and shifting populations.

Variation in Age Ratio of Midcontinent Greater White-Fronted Geese During Fall Migration

AbstractAnnual productivity is an important parameter for the management of waterfowl populations. Fall age ratio (juveniles:total birds) is an index of productivity of the preceding breeding season. However, differences in the timing of migration between family groups and nonbreeding birds may bias age-ratio estimates. We examined temporal variation in age ratios of midcontinent greater white-fronted geese Anser albifrons frontalis from interior and northwestern Alaska at a northern autumn staging area near Delta Junction, Alaska. Photographic sampling conducted near Delta Junction resulted in an annual age ratio of 0.388 ± 0.004 (mean ± SE) in 2010 and 0.390 ± 0.001 in 2011. Our study demonstrated temporal variation in age ratios over the duration of the migration period during August and September. We recommend that sampling be conducted for 3-d periods at the beginning, middle, and end of the migration period to account for temporal variation in migration of family groups.

Collision Risk of White-Fronted Geese with Wind Turbines

Recently, to help curb anthropogenic climate change and fossil fuel depletion, there has been a rapid increase in the number of wind farms being built worldwide. However, the construction of wind farms in the foraging areas of raptors or along the routes of migratory birds raises concerns about avian collisions and habitat loss. Here, we present an additional situation in which avian collisions may present a problem. That is, when wind farms are built between roosting and foraging areas of over wintering migratory birds, the bird flocks are forced to pass through the farm each morning and evening. Indeed, at the Awara Wind Farm in Fukui Prefecture, Japan, approximately three thousand White-fronted Geese Anser albifrons frontalis inhabit the site where the installation of 10 wind turbines has recently been completed. The collision risk posed by these turbines may affect the goose population. However, few studies have examined the effects of wind farms on the flight patterns of geese, making it difficult for stakeholders to achieve a consensus. The purpose of this study was to evaluate the collision risk for geese in the planning phase of the Awara Wind Farm. A collision model based on goose avoidance behavior was developed to predict collision mortality, and an applied potential biological removal (PBR) analysis was used to determine the maximum allowable collision mortality (ACM) whilst maintaining a sustainable goose population. The estimated annual collision mortality was 0–2 geese, whereas the allowable collision mortality was 75 geese per year, suggesting that the collision risk is sufficiently small for the population to persist. We also include a discussion of adaptive management plans for regulating wind turbine operations when the actual collision mortality exceeds the socially acceptable level.

Current Status and Distribution of Greater White-Fronted Goose in Japan

Abstract The numbers of the Greater White-fronted Geese Anser albifrons frontalis were monitored during winters from 2003/2004 to 2006/2007 throughout Japan. The annual average number of geese in Japan increased from 91,000 to 115,000 during these years and the maximum number reached was 138,000 in 2006/2007. Most geese (84%) stayed in northern Miyagi, and residual flocks were observed in other areas during winter. In the largest wintering area for this species in northern Miyagi, the number of geese has increased from 15,000 in 1987/1988 to 111,000 in 2006/2007.