Late Summer Movements by Giant Canada Geese in Relation to a September Hunting Season

The population of giant Canada geese (Branta canadensis maxima) breeding in eastern South Dakota has increased dramatically since reintroduction efforts began in the 1960s. May breeding population levels of giant Canada geese exceeded population management goals set by the South Dakota Department of Game, Fish and Parks (SDGFP) by the mid-1990s, and the population has continued to increase into the 2000s. This population increase was accompanied by an increase in goose-related conflicts such as crop depredation. In 1996, a September hunting season was implemented in select counties in eastern South Dakota in an effort to reduce the giant Canada goose population. After its implementation, some hunters and biologists were concerned that the early September season was causing Canada geese to disperse from areas open to hunting due to hunting pressure. Herein, we describe post-molt movements by geese, particularly in relation to the September hunting season. We caught Canada geese in 7 counties in eastern South Dakota during the summer molting period, 2000 to 2003. We attached VHF (n = 153) and satellite transmitters (n = 43) on adult female geese with broods. We monitored movements of marked geese weekly from July through the fall freezing period. For this study, we considered major movements any postmolt movement ≥40 km from the wetland in which the goose was banded prior to October 15. Forty-six percent of marked geese made major movements from July to September, and 43% moved during the first week of the September season, indicating that the season may have triggered their post-molt movement. Major movements were primarily in a northerly direction, and the longest documented post-molt movement was 474 km north. It appears that the onset of the September hunting season may have caused geese to move immediately before or during the first 10 days of the season. Post-molt movements prior to the September hunting season may simply have been a function of established, learned traditions, but the punctuated movement of geese during the opening weekend of the hunting season may have resulted from geese responding to the hunting season itself

Factors influencing wetland use by Canada geese

Seasonal and semi-permanent wetlands in eastern South Dakota were surveyed in 1995 and 1996 to identify habitat characteristics influencing wetland use by Canada geese (Branta canadensis maxima). Position of a wetland within the landscape and its area were important landscape-scale features influencing wetland use by geese. Our delineation of potential Canada goose habitat using a wetland geographic information system indicated that distribution and area of semi-permanent wetlands likely limit Canada goose occurrence in regions outside the Prairie Coteau. Periodicity in hydrologic cycles within landscapes also may influence goose use of wetlands in eastern South Dakota

Harvest Demographics of Temperate-breeding Canada Geese in South Dakota, 1967–1995

In South Dakota, breeding giant Canada geese (Branta canadensis maxima) have increased substantially, and harvest management strategies have been implemented to maximize hunting opportunity (e.g., special early-September seasons) on local, as well as molt-migrant giant Canada geese (B. c. interior) while still protecting lesser abundant Arcticbreeding Canada geese and cackling geese (e.g., B. hutchinsii, B. minima). Information on important parameters, such as survival and recovery rates, are generally lacking for giant Canada geese in the northern Great Plains. Patterns in Canada goose band recoveries can provide insight into the distribution, chronology, and harvest pressures to which a given goose population segment is exposed. We studied spatial and temporal recovery patterns of molting Canada geese during annual banding efforts in South Dakota between 1967 and 1995. Recovery rates (% ± SE) for Canada geese increased over time in both western South Dakota (0.034 ± 0.005 [1967 to 1976], 0.056 ± 0.009 [1977 to 1986]) and eastern (0.026 ± 0.002 [1967 to 1978], 0.058 ± 0.003 [1987 to 1995]) South Dakota. Although recovery rates for Canada geese west of the Missouri River (WR) and east of the Missouri River (ER) were relatively similar, recovery distribution and harvest chronology indicate spatial and temporal differences for geese banded in these 2 geographic regions. Overall, Canada geese banded in South Dakota were recovered in 23 states and 5 Canadian provinces, and recovery distribution varied relative to banding region. Distribution of recoveries suggests a south-southwesterly movement for WR-banded geese compared to a south-southeasterly movement for ERbanded geese. For WR-banded geese, 40 to 52% and 30 to 34% of direct and indirect recoveries, respectively, occurred in December. In contrast, for ER-banded geese, 19 to 38% and 15 to 19% of direct and indirect recoveries, respectively, occurred in December. Waterfowl managers need to consider that recovery rates and harvest chronology of banded giant Canada geese may vary geographically within a state or province. Refinement of harvest management strategies at multiple spatial scales may be required

Survival and Harvest Characteristics of Giant Canada Geese in Eastern South Dakota, 2000–2004

The population of giant Canada geese (Branta canadensis maxima) in eastern South Dakota has increased substantially since reintroduction efforts began in the 1960s. Breeding population estimates of Canada geese exceeded the population management objective of the South Dakota Game, Fish and Parks by the mid-1990s and has continued to increase at an estimated rate of 3 to 5% per year. Goose-related crop damage complaints have also increased. In 1996, a September hunting season (September 1 to 15) was implemented in 10 counties in eastern South Dakota and was expanded in 2000 to include most of eastern South Dakota. We initiated this study during 2000 to 2004 to estimate survival, harvest, and recovery rates of giant Canada geese. We captured and leg-banded Canada geese in 7 counties in eastern South Dakota during the summers of 2000 to 2003. Of the total leg-banded sample (n = 3,839), we recovered 648 bands during the same year that they were placed on geese (i.e., direct harvest rate), and we recovered 645 banded geese in later years (i.e., indirect recovery rate). Estimates of annual survival rate (95% CI) for adults and immatures were 0.52 (0.46 to 0.59) and 0.68 (0.57 to 0.79), respectively. Estimates of annual recovery rates (95% CI) for adult and immature geese were 0.16 (0.13 to 0.19) and 0.18 (0.14 to 0.21), respectively. Of the total recoveries, 77 and 69% of direct and indirect band recoveries, respectively, occurred in South Dakota. The composite harvest rate estimate during the period studied was 0.22 (0.20 to 0.24). Forty-nine percent of adult recoveries and 44% of immature recoveries (direct and indirect pooled for both age classes) occurred during the September season. In comparison to a previous band-recovery study of resident giant Canada geese in eastern South Dakota, survival rates for both adult and immature geese have declined, while recovery and harvest rates have increased. Survival estimates for this study were some of the lowest documented for giant Canada geese. However, it appears that even with a September hunting season targeting the local breeding population, declines in adult survival documented during this study are not reducing the population. Alternative management strategies may be necessary to reduce the population to achieve the management objective

Factors influencing wetland use by Canada geese

Seasonal and semi-permanent wetlands in eastern South Dakota were surveyed in 1995 and 1996 to identify habitat characteristics influencing wetland use by Canada geese (Branta canadensis maxima). Position of a wetland within the landscape and its area were important landscape-scale features influencing wetland use by geese. Our delineation of potential Canada goose habitat using a wetland geographic information system indicated that distribution and area of semi-permanent wetlands likely limit Canada goose occurrence in regions outside the Prairie Coteau. Periodicity in hydrologic cycles within landscapes also may influence goose use of wetlands in eastern South Dakota.This article is from Wetlands 17 (1997): 552–558, doi:10.1007/BF03161521.</p

Harvest Demographics of Temperate-Breeding Canada Geese in South Dakota, 1967–1995

In South Dakota, breeding giant Canada geese (Branta canadensis maxima) have increased substantially, and harvest management strategies have been implemented to maximize hunting opportunity (e.g., special early-September seasons) on local, as well as molt-migrant giant Canada geese (B. c. interior) while still protecting lesser abundant Arctic breeding Canada geese and cackling geese (e.g., B. hutchinsii, B. minima). Information on important parameters, such as survival and recovery rates, are generally lacking for giant Canada geese in the northern Great Plains. Patterns in Canada goose band recoveries can provide insight into the distribution, chronology, and harvest pressures to which a given goose population segment is exposed. We studied spatial and temporal recovery patterns of molting Canada geese during annual banding efforts in South Dakota between 1967 and 1995. Recovery rates (% ± SE) for Canada geese increased over time in both western South Dakota (0.034 ± 0.005 [1967 to 1976], 0.056 ± 0.009 [1977 to 1986]) and eastern (0.026 ± 0.002 [1967 to 1978], 0.058 ± 0.003 [1987 to 1995]) South Dakota. Although recovery rates for Canada geese west of the Missouri River (WR) and east of the Missouri River (ER) were relatively similar, recovery distribution and harvest chronology indicate spatial and temporal differences for geese banded in these 2 geographic regions. Overall, Canada geese banded in South Dakota were recovered in 23 states and 5 Canadian provinces, and recovery distribution varied relative to banding region. Distribution of recoveries suggests a south-southwesterly movement for WR-banded geese compared to a south-southeasterly movement for ERbanded geese. For WR-banded geese, 40 to 52% and 30 to 34% of direct and indirect recoveries, respectively, occurred in December. In contrast, for ER-banded geese, 19 to 38% and 15 to 19% of direct and indirect recoveries, respectively, occurred in December. Waterfowl managers need to consider that recovery rates and harvest chronology of banded giant Canada geese may vary geographically within a state or province. Refinement of harvest management strategies at multiple spatial scales may be require

Data from: Ecological causes and consequences of intratropical migration in temperate-breeding migratory birds

New discoveries from direct tracking of temperate-breeding passerines show that intratropical migration (ITM) occurs in a growing number of species, which has important implications for understanding their evolution of migration, population dynamics, and conservation needs. Our large sample size ([Formula: see text]) for purple martins (Progne subis subis) tracked with geolocators to winter sites in Brazil, combined with geolocator deployments at breeding colonies across North America, allowed us to test hypotheses for ITM, something which has not yet been possible to do for other species. ITM in purple martins was not obligate; only 44% of individuals exhibited ITM, and movements were not coordinated in time or space. We found no evidence to support the resource hypothesis; rainfall and temperature experienced by individual birds during their last 2 weeks at their first roost site were similar to conditions at their second roost site after ITM. Birds generally migrated away from the heavily forested northwestern Amazon to less forested regions to the south and east. ITM in this aerial insectivore appears to support the competition-avoidance hypothesis and may be triggered by increasing local density in the core wintering region. Full life cycle models and migratory networks will need to incorporate ITM to properly address seasonal carryover effects and identify which wintering regions are most important for conservation

The influence of morphological variation on migration performance in a trans-hemispheric migratory songbird

For long-distance migratory songbirds, morphological traits such as longer wings and a smaller body size are predicted to increase migration efficiency. Due to previous limitations in our ability to track the long-distance journeys of small-bodied birds, the relationship between morphology and start-to-finish migration performance has never been fully tested in free-living songbirds. Using direct-tracking data obtained from light-level geolocators, we examined the effects of morphological factors (wing and body size) on spring and fall migration performance (flight speed, duration of stopovers, total stopovers taken) of a widely distributed, trans-hemispheric migratory songbird, the purple martin (Progne subis) (n = 120). We found that smaller-bodied birds spent fewer days at stopovers along fall migration, but larger-bodied birds spent fewer days at stopover and took fewer stopovers during spring migration. More of the variation in fall migration performance was explained by morphology, as compared to spring migration, possibly indicating a larger influence of environmental conditions on spring performance. Overall, our results partially support long-standing and previously untested predictions regarding the influence of intrinsic factors on migration performance. Future research should examine the influence of environmental variation on migration performance as well as additional morphological traits that may contribute to migration performance

Purple Martin Intratropical Migration Data - Stutchbury et al

Timing of migration and location of wintering roosts for Purple Martins tracked by deploying geolocator tracking devices at multiple breeding colonies in North Americ