Since the mid 1990s, the number of black brant (Branta bernicla nigricans; brant) nests on the Yukon-Kuskokwim Delta (YKD), Alaska, USA, the historically predominant breeding area of brant, has declined steadily. This has caused researchers and managers to question if arctic breeding populations can compensate for the reduction in brant nests on the YKD. An important component of the assessment of brant population dynamics is having current estimates of first-year and adult survival. We banded brant at 4 locations in Arctic Alaska and western Canada, and at 1 location in the subarctic, the Tutakoke River (TR) colony on the YKD, 1990-2015. We used joint live and dead mark-recapture models to estimate first-year and adult (!1 yr old) survival of brant. We also used band recovery rates from a Brownie model to assess temporal trends in band recovery rates of adult brant. First-year survival of brant hatched at TR declined from approximately 0.60 to <0.20 and, although first-year survival generally was higher for goslings marked in the Arctic, their survival declined from approximately 0.70 in the early 1990s to 0.45 in the 2010s. Annual survival of adult females decreased from an average of 0.881 (95% CI ¼ 0.877-0.885) to 0.822 (95% CI ¼ 0.815-0.829) at TR and from 0.851 (95% CI ¼ 0.843-0.860) to 0.821 (95% CI ¼ 0.805-0.836) in the Arctic, from 1990 to 2014. Band recovery rates of adults generally were <1.25% until the last several years of study, when they reached 3.5%. Although the current harvest rates may be partially additive to natural mortality, we do not believe that harvest is the main influence on the declines in survival. The general decline in survival rates of brant breeding across a large geographic area may be influenced by a reduction in the quality of migration and wintering ground habitats. We suggest an analysis of seasonal survival of brant to test the hypothesis that declining habitat quality on wintering or spring migration areas is reducing survival. Our results suggest that the number of breeding pairs at TR will continue to decline and also brings into question the ability of arctic breeding populations to grow at a rate necessary to offset the declines on the YKD. Researchers should continue to closely monitor survival and harvest rates of brant, and assess methods currently used to monitor their abundance. Ó 2017 The Wildlife Society.KEY WORDS band recovery rates, Branta bernicla nigricans, Brownie models, joint live and dead mark-recapture, population dynamics, Seber reporting rate.

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American peregrine falcons (Falco peregrinus anatum) throughout North America declined following the introduction of dichlorodiphenyltrichloroethane (DDT) in 1947. In the 1960s, intensive studies were initiated in many areas of North America, including interior Alaska, to determine the cause of the decline and assess population status. From 1977 to 2015, we studied peregrine falcons along a 265‐km section of the upper Yukon River in east‐central Alaska. We counted occupied territories, documented breeding success and productivity, and collected unhatched eggs for contaminant analysis. We observed 1,602 occupied territories and 2,349 nestlings. Annual breeding success averaged 64%, and annual productivity averaged 1.54 nestlings/territory and 2.38 nestlings/successful territory. Annual rates of increase in the number of occupied territories were greatest in the late 1970s and 1980s (8.6%), moderate in the 1990s (2.8%), and least in the 2000s (1.5%). Reproductive metrics were highest in the late 1970s and 1980s, declining in recent years. As the number of occupied territories increased (14–60) and average nearest neighbor distance decreased (from 9.8 km to 2.6 km), breeding success declined (from 71% in the 1980s to 57% in the 2000s). Productivity, as measured by nestlings per occupied territory, declined (from 1.84 in the 1980s to 1.29 in the 2000s). Nestlings per successful territory also declined from 2.56 in the 1980s to 2.25 in the 2000s. Survey data for 1966–2015 reveal a declining population in the 1960s and early 1970s, increasing in the late 1970s through the early 2000s, and apparently stabilizing in recent years. The recovery of this local population took roughly 40 years, from a low of 12 occupied territories in early 1970s to 60 in 2012–2014. Importantly, the recovery of American peregrine falcons in Alaska occurred without captive breeding, releases, or nest site manipulations. Long‐term studies are essential in fully understanding the biology of any species, and this study provides insight into the unaided, natural recovery of American peregrine falcons in Alaska. © 2016 The Wildlife Society.

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The distribution and abundance of brant (Branta bernicla) were surveyed on the central Arctic Coastal Plain of Alaska between 1989 and 1992. Numbers of nests ranged between 319 and 517 in 43 to 67 locations. More than 70% of the nesting locations consisted of ≤ 5 nests; only one or two locations had ≥ 100 nests in any year. Brant attempted to nest every year at primary sites, but less frequently at secondary and solitary nest sites. Estimated numbers of nesting brant averaged 800 birds (range = 630-1064); failed and nonbreeding brant ranged between 293 and 740 birds. During brood-rearing, approximately 900 to 3200 brant (26% to 48% goslings) used coastal habitats within the study area. Some coastal habitats were used annually; others were used only intermittently. Inland lakes were used by only a few brant each year. The earliest comparable data from the mid-1970s suggest that the population of brant in the study area has remained fairly stable. Factors affecting distribution of brant within the study area included environmental conditions, such as snowmelt and persistent ice, and predators. Indirect effects of oil development on brant distribution may include temporarily altered hydrologic regimes and elevated predator populations.