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Current assessments indicate that populations of several species of North American shorebirds are declining rapidly. However, limited monitoring programs south of the U.S.-Mexico border have precluded assessments of the conservation status of temperate breeders on their principal wintering grounds. The Migratory Shorebird Project (MSP), active since 2011 throughout the Pacific Americas Flyway, provides an opportunity to detect changes in non-breeding shorebird distribution and abundance. We used annual survey data collected using the MSP monitoring protocol to assess population trends of three temperate breeders: Marbled Godwit (Limosa fedoa), Willet (Tringa semipalmata), and Long-billed Curlew (Numeniues americanus) on their main wintering grounds in northwest Mexico and California. We also analyzed the associations between fluctuations in their abundance and environmental variables using Generalized Linear Mixed Models. We found a significant negative trend in the wintering population of Marbled Godwit and Willet in California and the Baja California Peninsula (BCP). The BCP was the most important region for these three species in the study area, followed by Sonora, Sinaloa, Nayarit (SSN), and California. In addition, we determined that Marbled Godwit abundance was negatively associated with precipitation and positively associated with minimum temperature from January. Willet abundance also was positively associated with minimum temperature, but negatively with sea surface temperature and precipitation. Association of Long-billed Curlew abundance with precipitation was positive and significant. Our study provides evidence that temperate shorebirds are declining and their fluctuations are associated to environmental variables, and highlights the importance of long-term winter shorebird surveys for understanding drivers of populations change that can then be used to identify management and adaptation strategies.

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The study of avian movement has detailed a spectrum of strategies for the timing and use of sites throughout the annual cycle, from near randomness to complete consistency. New tracking devices now permit the repeated tracking of individual animals throughout the annual cycle, detailing previously unappreciated levels of variation within migratory systems. Godwits (genus Limosa) have featured prominently in studies of avian migration, but information derived from repeated tracking of individuals is limited. The Marbled Godwit subspecies Limosa fedoa beringiae breeds on the central Alaska Peninsula, and little is known about basic aspects of its migration ecology, including the repeatability with which this population times its annual migratory movements or uses migratory and nonbreeding sites. To address these questions, we equipped 9 Marbled Godwits breeding at a site near Ugashik, Alaska, with solar-powered satellite transmitters. We tracked individuals from July, 2008 to October, 2015 and obtained repeat migratory tracks from 5 of these birds. Individuals exhibited high fidelity to breeding, nonbreeding, and migratory stopover sites across years, but in contrast to congeners that conduct consistently timed, long, nonstop migrations, beringiae Marbled Godwits exhibited low levels of individual- or population-level repeatability in the timing of migratory movements. Their relatively short migrations may enable the integration of local environmental cues, potentially facilitating individual flexibility in the timing of annual migratory movements. Curiously, if local cues ultimately drive the timing of Marbled Godwit migratory movements, the population's relatively constrained distribution during both the breeding and nonbreeding season should serve to synchronize birds if they are responding to similar cues. That our sample of Marbled Godwits nonetheless exhibited within- and between-year variation in the timing of their migratory movements suggests a complex integration of annually variable internal and external cues. [ABSTRACT FROM AUTHOR]

As breeding populations of many grassland bird species decline, assessments of breeding habitat selection and reproductive success can provide useful insight into breeding ecology to support conservation delivery. Here, we demonstrate the use of nest location and survival data collated from 20 data contributors across the Prairie Pothole Region of the United States and Canada over a half century to examine habitat selection and nest survival of Western Willets (Tringa semipalmata inornata) and Marbled Godwits (Limosa fedoa), hereafter "willets" and "godwits." Both willets and godwits selected territories with less variation in vegetation height and topography relative to available locations. Willets selected nest sites that were flatter, closer to wetlands, and had shorter vegetation than Marbled Godwits, while godwits selected territories with greater wetland cover and shorter vegetation. Despite differences in fine-scale habitat selection, willets and godwits experienced similar daily nest survival rates and ecological drivers of nest survival. Nest success for the entire nest exposure period was estimated to be 0.521 (95% credible interval: 0.39-0.65) for willets and 0.562 (95% credible interval: 0.42-0.70) for godwits. Nest survival for both species increased with nest age and distance from the nest to the nearest wetland edge, while nest survival of godwits declined with conspecific breeding density. These relationships, as well as a weaker positive effect of microtine rodent abundance on nest survival, resembled drivers of upland nesting waterfowl reproductive success in the same region, which we attribute to their shared nest predators. Nest survival analyses of our collaborative dataset required substantial consideration of biases emerging from different data collection methods, ultimately reaffirming the importance of nest aging techniques in proper nest fate assignment. Analysis of compiled datasets using emerging analysis methods will continue to grow our understanding of the ecology of data sparse species.

ABSTRACT With the loss of over 70% of North America's grasslands (Samson et al. 2004), grassland birds increasingly rely on habitat that is privately owned and managed for livestock production. Therefore, it is critical to understand how livestock grazing influences grassland bird abundance and community structure. We evaluated the response of 4 obligate grassland bird species to grazing intensity, vegetation structure, ecological site description, and burning across a landscape including pastures with no recent grazing to pastures experiencing grazing intensities similar to that for private livestock production operations. We evaluated models using a binomial N-mixture model implemented in the R package unmarked. Overall, 3 of the 4 obligate species included positive relationships with grazing intensity in the top abundance model (i.e., grasshopper sparrow [ Ammodramus savannarum], bobolink [ Dolichonyx oryzivorus], and upland sandpiper [ Bartramia longicauda]), suggesting the range of grazing intensities evaluated (0-4.57 animal months/ha) did not negatively affect the abundance of these species. Marbled godwit ( Limosa fedoa) abundance, however, was higher with greater variability in litter depth but was not directly related to grazing intensity. Finally, the effect of year was correlated with decreasing precipitation over the course of the study and had the greatest influence on community composition with some community separation by grazing intensity. Our results suggest that cattle grazing can positively influence the abundance of some grassland bird species but annual variation in weather patterns can influence community composition at sites regardless of management decisions. © 2016 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Marbled Godwits {Limosa fedoa) breed in 3 disparate areas: The majority breed in the prairies of midcontinental North America, but there are also 2 small and widely separated tundra-breeding populations, 1 in eastern Canada and 1 on the Alaska Peninsula, USA. The major winter ranges include the Atlantic, Pacific, and Gulf coasts of the USA and Mexico. Bear River Migratory Bird Refuge at Great Salt Lake, Utah, USA, is a major stopover site, hosting large godwit populations in the spring and fall. Although the distributions of Marbled Godwit populations and their hábitats across the landscape are generally known, the linkages between them are not. We tracked 23 Marbled Godwits equipped with satellite transmitters from sites in Utah, Mexico, Canada, and coastal Georgia during 2006-2010. Our goals were to characterize the migration strategy of Marbled Godwit populations and to determine migratory connectivity of major breeding, staging, and wintering areas. We found that: 1) godwits breeding in the western USA and Canada followed an overland route to winter sites in Mexico after departing their Utah stopover site; 2) godwits tagged in eastern Canada migrated across the continental USA and wintered at sites along the Gulf of California, Mexico; and 3) godwits wintering in coastal Georgia bred in North and South Dakota. We believe this to be the first demonstration of a continental "crisscross" migration pattern in a shorebird. We identified differences in migration elements such as distances traveled, timing of migration, duration, residency, and stopover strategy between the subpopulations, but not between males and females. [ABSTRACT FROM AUTHOR]

The article focuses on a study which determined a noninvasive and cost effective technique for the correct identification of the sex of Marbled Godwits in the field using only phenotypic measurements. An overview is given on the difficulty in identifying the sex of shorebirds and the reason why some aspects of sex differences in ecological processes are poorly understood. The findings of the research indicated that culmen length is a useful measure for sex determination in Marbled Godwit.

Copyright of Canadian Field-Naturalist is the property of Ottawa Field Naturalists' Club and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Avian Conservation & Ecology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article offers information on fatal interaction of marbled godwit with ribbed mussel. Topics include, breeding of marbled godwit in the grasslands of the north-central U.S. and south-central Canada; bird species with bivalves attached to the bill or foot; and spatial distribution & density of the ribbed mussel & its interactions with other species.

Wetlands in southern Alberta are often managed to benefit waterfowl and cattle production. Effects on other species usually are not examined. I determined the effect of managed wetlands on upland-nesting shorebirds in southern Alberta by comparing numbers of breeding willets (Catoptrophorus semipalmatus), marbled godwits (Limosa fedoa), and long-billed curlews (Numenius americanus) among areas of managed wetlands, natural wetland basins, and no wetland basins from 1995 to 2000. Surveys were carried out at 21 sites three times each year. Nine to ten of these areas (each 2 km2) were searched for nests annually from 1998-2000. Numbers of willets and marbled godwits and their nests were always highest in areas with managed wetlands, probably because almost all natural wetland basins were dry in this region in most years. Densities of willets seen during pre-incubation surveys averaged 2.3 birds/km2 in areas of managed wetlands, 0.4 in areas of natural wetland basins, and 0.1 in areas with no wetland basins. Nest densities of willets (one search each season) averaged 1.5, 0.9, and 0.3 nests/km2 in areas of managed, natural, and no wetland basins, respectively. Similarly, pre-incubation surveys averaged 1.6, 0.6, and 0.2 godwits/km2 in areas of managed, natural, and no wetland basins, and 1.2, 0.3, and 0.1 godwit nests/km2. For long-billed curlews, pre-incubation surveys averaged 0.1, 0.2, and 0.1 birds/km2, and 0, 0.2, and 0 nests/km2. Nest success was similar in areas with and without managed wetlands. Shallow managed wetlands in this region appear beneficial to willets and marbled godwits, but not necessarily to long-billed curlews. Only 8% of marked willets and godwits with nests in the area were seen or heard during surveys, compared with 29% of pre-laying individuals and 42% of birds with broods. This suggests that a low and variable percentage of these birds is counted during breeding bird surveys, likely limiting their ability to adequately monitor populations of these species.

On 25 August, 2007, a Marbled Godwit (Limosa fedoa) was struck by a Southwest Airlines Boeing 737 at 3,700 m. The bird was identified by examination of feather remains recovered from the aircraft and represents an altitude record for this species. [ABSTRACT FROM AUTHOR]